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Children's Use of Different Information Types When Learning Homophones and Nonce Words
Cognitive Development, 14, 515–530 (1999) ISSN 0885-2014
© 2000 Elsevier Science Inc. All rights of reproduction reserved.
Children’s Use of Different Information Types When Learning Homophones and Nonce Words Andrea G. Backscheider University of Houston, Houston, TX, USA
Susan A. Gelman Ivelisse Martinez University of Michigan, Ann Arbor, MI, USA
Jennifer Kowieski University of Notre Dame, South Bend, IN, USA This study examines whether 3-year-olds are able to use ontological distinctions in homophone and nonce word acquisition. In the homophone (denotation-1 present) condition, children heard stories introducing second meanings of homophones; for example, a skate (i.e., fish). Stories contained perceptual information, information about theory-based properties, or filler material. Children identified the referent from 3 drawings depicting the familiar meaning, the secondary meaning, and a distractor. In the homophone (denotation-1 absent) condition, the picture of the familiar meaning was replaced with a distractor. The nonce word condition, a control condition, was identical to the homophone (denotation-1 present) condition except that a nonce word replaced the homophone. Children were rarely able to construct a sec-
This work was supported in part by a National Science Foundation Predoctoral Fellowship to Andrea Backscheider and a J. S. Guggenheim Fellowship and NICHD grant HD36043 to Susan Gelman. Portions of this work were presented the 1997 Biennial Meeting of the Society for Research in Child Development, Washington, D. C. We would like to thank the children, parents, and staff of Friends School, Tutor Time Learning Center, Red Barn Learning Center, and the Shamrock School of South Bend, and the University of Michigan Children’s Centers for their participation in this research. We would like to thank Cari McCarty, Chris Kubischek, Sarah Tschaen, Yvette Ramirez, and Jennifer Mullins for their helpful comments and their assistance in data collection. We would also like to thank two anonymous reviewers for their helpful comments. Direct all correspondence to: Andrea G. Backscheider, Department of Educational Psychology, University of Houston, Houston, TX 77204; E-mail: [email protected] Manuscript received September 26, 1997; revision accepted June 21, 1999
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ond homophone interpretation when the familiar denotation was available. Interestingly, in the remaining conditions, children used information about the animate-inanimate distinction in choosing the referent. We discuss children’s use of this ontological distinction when inducing word meaning.
When children hear a new word, their task of mapping the unfamiliar word to a referent is not a trivial one. Children must determine the word meaning from an infinite number of possibilities (Quine, 1960). In the case of learning second meanings1 of homophones, the task is even more difficult. Children must not only isolate the correct meaning from the context, but also realize that a familiar phonological pattern does not map to the accustomed meaning. For example, a child who has only heard the word “bat” refer to a piece of sports equipment will at some point hear “bat” denoting a flying mammal. In order to map “bat” correctly to the new meaning, the child must realize that (a) the familiar pattern of sounds is not being used to denote a baseball bat, and also that (b) it denotes a flying mammal. Mapping a novel word to a referent is a task at which young children excel (Carey, 1977; Markman, 1989); however, mapping a homophone to its secondary meaning seems to pose a problem for children during the preschool and elementary school years. Although Backscheider and Gelman (1995) found that 3-year-olds can identify both meanings of some common homophones even when both denotations are presented together, other researchers have had little success teaching children second meanings of known words. Campbell and Macdonald (1983) found that 3- to 5-year-old children tend to interpret novel homophones presented in context as having the meaning which is most familiar to them, even when this meaning is not consistent with the information presented in the context. Similarly, Beveridge and Marsh (1991) investigated the role of context in children’s ability to determine the secondary meaning of a homophone. The experimenter read 3- to 6-year-olds stories incorporating the secondary meanings of homophones. Some stories included elaborated contexts; that is, increased perceptual and functional information. Although the elaborated context helped children realize that the homophone denoted the secondary meaning, even when this context was present 3-year-olds chose the secondary denotation on only 18% of the trials, and 6-year-olds chose correctly on only 42% of the trials. Finally, Mazzocco (1997) found that preschoolers and second graders were less able to use context to interpret pseudo-homonyms (familiar English words used as hom-
1Throughout this paper, the term “meaning” is used to refer to the sense of the homophone. Thus, when we say that young children do not know the secondary meaning, we assert that although the children are familiar with the primary sense of the homophone, they are not yet familiar with the secondary sense. The term “denotation” is used to refer to the class of potential referents (see Lyons, 1977).
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onyms in the experiment) than to interpret novel words. Thus, the literature indicates that although children do know some homophones, it is difficult to teach second meanings of known words. How then, if children have difficulty learning the second meanings, do 3-year-olds know so many homophones? In this research, we manipulate several factors to examine children’s acquisition of new words and second meanings of familiar words. First, the present research examines the effect of context on children’s performance. Campbell and Macdonald (1983) found that children often failed to use context to determine the meaning of homophones, and Beveridge and Marsh (1991) found that although children performed better with elaborated context, children certainly had difficulty using context to determine word meanings. However, one question that has not been examined is what type of context helps children realize that a known word has a second sense. In this research, we examine whether different types of information help children determine the secondary senses of homophones. Specifically, we examine (i) the effect of information about the perceptual properties of the objects (perceptual information) and (ii) what we will refer to as theorybased information. In this way the present experiment examines whether certain types of information are particularly useful in helping children induce the meaning of homophones and nonce words (that is, nonsense word forms referring to the secondary denotation of the homophone). Piagetian theory (Inhelder and Piaget, 1964) suggests that preschoolers should be able to use perceptual information, but not information relying on more abstract properties. In contrast, recent research has indicated that children may build “naïve theories” to reason about the world (Wellman & Gelman, 1992; Wellman & Gopnik, 1994). These theories are coherent, domain-specific causalexplanatory frameworks that allow children to reason in a consistent, but not necessarily adultlike, fashion. Thus, children may use a naïve physics to reason about object motion and a naïve psychology to reason about human behavior. There is more debate about whether preschoolers reason according to biological principles, but there is some consensus that preschoolers are learning about biological phenomena (such as growth) during the preschool years (Carey, 1985, 1995; Wellman & Gelman, 1992; Keil, 1992; Springer, 1995) and that they recognize the animate-inanimate distinction (Gelman, Durgin, & Kaufman, 1995; Massey & Gelman, 1988). Moreover, S. Gelman and her colleagues have found that young preschoolers appreciate that nonobvious properties are important in reasoning about natural kind categories (Gelman, 1988; Gelman & Coley, 1990; Gelman & Markman, 1987), suggesting that they may find information about nonperceptual properties useful. Taken together, previous research suggests that although 3-year-olds may not yet hold a naïve biological theory, the properties that will later constitute this theory hold a privileged place in their reasoning. Thus, stories that emphasize these properties may give children cues to set up a second meaning for a known word. In addition, given that from an early age children pay particular attention to the
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features that distinguish animates from inanimates (Mandler, 1992; Gelman, Durgin, & Kaufman, 1995), children may be better able to learn homophones when their first and second meanings cross this ontological boundary. Simply, children may be more likely to realize that a word has a second meaning when the new meaning is ontologically distinct from the familiar meaning. For example, children may have an easier time learning homophones such as bat, where one meaning refers to an animate and one to an inanimate, than bow, where both meanings refer to inanimates. Second, in the case of homophones we specifically manipulate the availability of the primary meaning as a response. In previous research, the situations that children faced were very different from what they might face in a natural setting. In Campbell and Macdonald’s (1983) research, children were asked to complete a drawing (e.g., they were asked to add the old “wing of the castle” to a partially drawn castle) after hearing a story; thus, although some context was provided, neither denotation of the homophone was present at the time the story was read. In a more natural setting, at the time that a new object term or homophone is introduced to a preschooler, the referent is likely to be present in the environment. In Beveridge and Marsh’s (1991) and Mazzocco’s (1997) research, after hearing the story children were asked to choose the homophone from pictures containing both the primary and secondary meanings. However, in most natural situations it seems likely that when preschoolers hear a homophone used in its secondary sense, the intended referent will be present and supported by the context whereas a referent consistent with the known, primary sense will not be present. For example, a baseball bat is unlikely to be present with a mammal-bat, and a bow (and arrow) is unlikely to be present with a hair bow. Therefore, children’s failure in these studies may be due less to an inability to use context to determine that the homophone refers to a second meaning than to an inability to inhibit the first meaning. Children may prove more able to assign a second meaning to a word when a referent for the familiar meaning is not available. Thus, in the following experiment we examine the effect of context and response set on children’s acquisition of homophones and nonce words. We hypothesize that children will be better able to identify the secondary denotation of a homophone when the primary denotation is not available. In addition, we investigate whether children find either theory-based or perceptual information particularly useful in isolating word meanings, and whether children are able to make use of the animate-inanimate distinction.
METHOD Participants Seventy-two 3- and 4-year-olds participated in the main experiment: 26 children in the nonce word condition (range ⫽ 3;1 to 4;1, M ⫽ 3;8, 14 girls and 12
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boys), 23 children in the homophone (denotation-1 present) condition (range ⫽ 3;0 to 4;6, M ⫽ 3;9, 14 girls and 9 boys), and 23 children in the homophone (denotation-1 absent) condition (range ⫽ 3;0 to 4;4, M ⫽ 3;8, 12 girls and 11 boys). All children were drawn from preschools serving a small midwestern city. Children were primarily middle-class and of European-American descent. American English was the first language of all children. Two additional children were eliminated because they answered a control story incorrectly. In addition, 12 children (range ⫽ 3;1 to 4;1, M ⫽ 3;7, 7 girls and 5 boys) participated in pilot testing of the items. Materials and design Nine homophones were selected. All homophones were English words or the first half of compound nouns (e.g., milk for milk snake). Homophones were selected such that for three homophones the primary sense (i.e., those already known) denoted inanimate items and the secondary sense (i.e., the meanings children were taught) denoted animate items (Inanimate/Animate items; e.g., skate: footwear/fish); for three homophones the primary sense denoted an animate item and the secondary sense denoted an inanimate item (Animate/Inanimate items; e.g., fox: animal/sword); and for three homophones both senses denoted inanimate objects (Inanimate/Inanimate items; e.g., log: piece of wood/diary).2 This selection allowed investigation of whether children are sensitive to domain differences in a word-learning task; that is, whether children are better able to isolate second senses when the meanings cross ontological boundaries than when the two senses denote objects in the same domain. The homophones are listed in Table 1. To examine the effect of information type, three stories were constructed for each homophone. Because previous research has shown that children have difficulty learning second senses for homophones, all stories contained several pieces of contextual information designed to alert children that the primary sense of the homophone was inappropriate. All stories began with the same first sentence, the constant information, but diverged at the second sentence, which contained the different types of information. The first sentence of the stories introduced the item and gave a property and setting diagnostic of the secondary sense but inconsistent with the primary sense (e.g., “the drill (snail) crawled beside the pond”). For the animates, these sentences described an animal doing something; for the inanimates, the first sentence described a person using the object for a purpose. Thus, these sentences set up situations that we hoped would alert the child that the word was being used in an unusual way; the following sentences would then give addi2Homophones were selected through a pilot study in which twelve 3- and 4-year-olds served as participants. All primary meanings were recognized by at least 11 participants; no secondary meanings were identified. Additionally, all children produced correct names (though not the homophones) for pictures of the secondary meanings.
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Table 1. List of Homophones Taught, Constant Information, Theory-Based Information, and Perceptual Information Homophone/ meaning Inanimate– animate Skate/fish Milk/snake Drill/snail Animate– inanimate Monkey/ jackhammer Fox/sword Buffalo/coat Inanimate– inanimate Log/diary
Constant information
Distinctive information given No-info
Theory-based
Perceptual
Swimming in ocean Frightened child Crawls by pond
Going to island
Eats
Is very large
Child ran to mom Was dry
Crawls Has children
Has stripes Has black spots
Used to break cement King carries to battle Worn for warmth
Job was hard
Is made of steel Has a blade
Is silver/heavy
Explorer got in Alaska
Has buttons
Is very long
Written in
Has pages
Is cooked
Has blue/red lettering Has curved top/ flat bottom Has white bottoms/ green tops
With king always
Plane/tool
Smooths wood
Writing about storm Kept in basement
Leak/leek
For dinner
Also had chicken
Is a tool
Is shiny/smooth
tional evidence that a new interpretation was necessary. As a result of this tactic, many of the properties given in the first sentence were theory-based (see below). However, this design should work against our hypothesis that there would be condition effects. To the extent that we find an effect of theory-based information, it is despite the conservative design of the study. Stories then continued with a second piece of information. In the perceptual information stories, the information concerned the appearance of the object (e.g., that the drill had black spots). In the no-information stories, children were given irrelevant information (e.g., that it had rained recently but the drill was dry). In the theory-based information stories, information included properties that previous research has suggested children are familiar with (Keil, 1989; Massey & Gelman, 1988; Rosengren, Gelman, Kalish, & McCormack, 1991; Wellman & Gelman, 1992) and that are likely to be present in children’s developing theories (Wellman & Gelman, 1992). These properties differentiate animates from inanimates and support category-based reasoning. For animates the properties used included growth, self-generated movement, and reproduction (e.g., that the drill had children), and for inanimates properties concerned parts and composition
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(e.g., that the monkey [jackhammer] was made of steel). Note that for the homonyms that did not cross domain boundaries, giving theory-based information that differentiated animates from inanimates does not help children determine the correct referent. Therefore, in these cases we gave information about function or superordinate category. For each homophone, the three stories were constructed to contain approximately the same number of words and syllables. See Table 1 for a list of properties. From the sets of homophones and stories, six datasheets containing different sets of stories were constructed. On each datasheet every homophone appeared exactly once in exactly one information condition. Across datasheets, each homophone appeared equally often in each information condition. For example, one-third of the datasheets contained the perceptual story for skate, one-third contained the theory-based story, and one-third contained the no-information story. Across homophones, each datasheet contained 3 perceptual stories, 3 theory-based stories, and 3 no-information stories. Thus, both the information type and domain comparisons were within-subject comparisons. For each homophone, a set of four line drawings was constructed. This set was paired with the homophone regardless of story type; that is, it was used for no-information, perceptual, and theory-based stories. One drawing depicted the primary sense of the homophone, one the secondary sense of the homophone, and two depicted distractors (see Table 2). We included distractors to eliminate the possible response strategy of choosing the only drawing that did not depict the familiar denotation. In order to allow children to use information regarding the animacy status of the items to choose the correct drawing, the distractors were chosen to be unrelated objects from the domain (animate or inanimate) of the primary sense of the homophone. Additionally, because previous research has shown that children have difficulty realizing that a speaker is using a known homophone in its secondary sense, distractors were chosen to be familiar to chil-
Table 2.
List of Homophones and Distractors
Homophone Inanimate–animate Skate Milk Drill Animate–inanimate Monkey Fox Buffalo Inanimate–inanimate Log Plane Leek
Distractor 1
Distractor 2
Purse Banana Lamp
Ice cream cone Kite Bow
Dog Fish Bird
Giraffe Bug Frog
Toothpaste Car Jug
Bike Ball Comb
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dren but clearly not intended referents of the story. Distractors were chosen to be familiar to eliminate the possibility that children would choose distractors because they were the only items for which the children did not have a name. Furthermore, in order to ease the processing demands on the children in an already difficult task, the distractors were chosen such that they were clearly not possible referents of the story. All items were pictured without a setting; for example, the drawing depicting the primary meaning of skate was a single roller skate on a white background. Thus, the constant information was not provided in any of the pictures. The theory-based information also was not depicted in the drawings; for example, living things were not shown eating or in motion. In contrast, perceptual information was represented to the extent possible in the drawings. In each set, the drawing of the secondary sense reflected the perceptual property given in the story (for example, the snail-drill had black spots), and the drawing of the familiar sense did not reflect the property. In addition, 3 control stories and picture sets were constructed. These stories concerned common items (not homophones) such as scissors. Procedure A familiar experimenter took children to a quiet corner of their classroom. Each child was randomly assigned to one datasheet with the constraint that datasheets were distributed such that each homonym was heard in each information condition with approximately equal frequency. The experimenter told the children that they would listen to some stories, then help the experimenter find the things in the stories. The first story was always a control story in which children were told about a common item such as scissors, and were then asked to find the scissors from the set of three pictures. In this example a picture of scissors was paired with two distractors. Then, children were presented with the nine experimental items and remaining control items in random order. In the homophone (denotation-1 present) condition, the experimenter read each story and showed the child the set of three line drawings from the picture set: the primary meaning, the secondary meaning, and the first distractor. The experimenter then asked the child, “Which one is the [homophone] that’s in the story?” For example, after reading the story about the drill, children were asked, “Which one is the drill that’s in the story?” If children indicated confusion or refused to choose, the experimenter reread the story and encouraged the child to make a best guess. The nonce word and homophone (denotation-1 absent) conditions were virtually identical to the homophone (denotation-1 present) condition. In the nonce word condition, however, the homophone was replaced by a nonce word modeled after the Spanish counterparts but with American English pronunciation: For example, the word “drill” was replaced with “caracol.” In the homophone (denotation-1 absent) condition the homophone was used, but the picture of the famil-
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iar meaning of the homophone was replaced by the second distractor (see the materials section). Thus, in this condition the primary meaning of the homophone was not available to the child as a choice. In all conditions, the left-to-right placement of the pictures was randomized.
RESULTS Preliminary analyses showed no effect of gender or datasheet; therefore these factors were excluded from the remaining analyses. The first analysis compares the number of correct responses (the secondary denotation of the homophone) given by the children in the homophone (denotation-1 present), homophone (denotation-1 absent), and nonce word conditions. A one-way analysis of variance (ANOVA) using the total number of correct pictures chosen showed a significant main effect of condition [F(2, 69) ⫽ 51.08, p ⬍ .001]. Tukey HSD tests indicated that children were significantly more likely (p ⬍ .001) to choose the correct picture in the homophone (denotation-1 absent) condition (M ⫽ 4.22 out of 9 correct, or 47%) than in the homophone (denotation-1 present) condition (M ⫽ 1.30 out of 9 correct, or 14%). In the homophone (denotation-1 present) condition, children chose the primary denotation of the homophone on 75% of the trials. Children were also significantly more likely to choose the correct homophone in the nonce word condition (M ⫽ 5.69 out of 9 correct, or 63%), than in either of the other conditions (p’s ⬍ .005). Note here that 3-year-olds had some difficulty finding the referent of the novel words. We next compared children’s performance to chance levels. Children were significantly less likely than chance (33%) to choose the correct picture in the homophone (denotation-1 present) condition (t (22) ⫽ 5.46, p ⬍ .001) and more likely than chance to choose the correct picture in the homophone (denotation-1 absent) and nonce word conditions (t’s ⬎ 3.28, p’s ⬍ .005). Hence, it is clear that the presence of a denotation for the familiar, primary sense interferes with children’s ability to choose a picture representing the secondary sense. Moreover, even when the familiar denotation is excluded as a choice, the presence of a homophone interferes with children’s ability to process the story and induce the correct word meaning. We then examined the effect of whether the homophone senses crossed the animate-inanimate domain boundary on children’s ability to choose a denotation of the secondary sense. For each child, we computed three scores: The number of animate-inanimate stories (primary meaning is an animate, secondary is an inanimate) answered correctly, the number of inanimate-animate stories answered correctly, and the number of inanimate-inanimate (no boundary crossed) stories answered correctly (see Table 3). A 3 (condition: homophone (denotation-1 present), homophone (denotation-1 absent), nonce word) by 3 (boundary crossed: animate-inanimate, inanimate-animate, inanimate-inanimate) repeated measures
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Table 3. Mean Proportion Correct for Stories that Crossed and Did Not Cross the Animate/Inanimate Domain Boundary Primary/secondary homophone sense Condition Nonce word Homophone (deont.-1 absent) Homophone (denot.-1 present)
Inanimate/animate Animate/inanimate Inanimate/inanimate .72 (.32) .54 (.34) .10 (.18)
.64 (.25) .45 (.29) .09 (.25)
.54 (.25) .42 (.23) .22 (.26)
SD given in parentheses. Note: Analyses were performed using children’s raw scores (out of 3), proportions are shown for ease of interpretation.
MANOVA indicated a main effect of condition [F(2, 69) ⫽ 54.23, p ⬍ .001] and a significant Condition ⫻ Boundary Crossed interaction (Wilks’ Lambda ⫽ .860, F(4, 136) ⫽ 2.66, p ⬍ .05). The main effect of condition indicates that, as discussed above, children were less likely to choose the correct answer when homophones were present. Post-hoc contrasts investigating the interaction indicated that children’s responses in the homophone (denotation-1 present) condition followed a different pattern from the nonce word and homophone (denotation-1 absent) conditions [F(2, 68) ⫽ 5.09, p ⬍ .01]. However, there was no significant difference between the pattern of children’s responses in the homophone (denotation-1 absent) and nonce word conditions (p ⬎ .10). In the homophone (denotation-1 present) condition, there was no effect of whether a domain boundary was crossed, as children were consistently performing poorly. In the remaining two conditions, planned comparisons indicated that children were better able to choose the correct picture when the story referred to an animate that was contrasted with inanimates than when the story concerned an inanimate contrasted with other inanimates (Bonferroni t(48) ⫽ 2.76, p ⬍ .05). Children’s percent correct on the stories contrasting inanimates with animates was not different from either of the other story types. Thus, there is some evidence that children are able to use information differentiating animates from inanimates when reasoning about word meanings. Last, we examined the effect of information type on children’s ability to choose the secondary meaning. Because theory-based information was designed to give children information about the animacy status of the items, this type of domain-specific information could only aid children’s reasoning when the senses of the homophones cross the animate/inanimate boundary. Thus, we eliminated the inanimate/inanimate stories from this analysis but analyzed them separately in a subsequent analysis. From the animate/inanimate and inanimate/animate stories where this boundary is relevant, we computed three scores for each child: The number of perceptual information stories answered correctly, the number of theory-based stories answered correctly, and the number of no-information stories answered correctly (see Table 4). In addition, because the children in the ho-
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Table 4. Mean Proportion Correct for Each Type of Information Given for Stories that Crossed and Did Not Cross the Animate/Inanimate Domain Boundary Information type Story type, with conditions Domain boundary crossed Nonce word Homophone (denot.-1 absent) Homophone (denot.-1 present) Domain boundary not crossed Nonce word Homophone (denot.-1 absent) Homophone (denot.-1 present)
No-information
Theory-based
Perceptual
.67 (.45) .46 (.33) .13 (.27)
.79 (.38) .54 (.37) .04 (.14)
.58 (.27) .48 (.32) .11 (.26)
.46 (.51) .52 (.51) .21 (.42)
.50 (.51) .26 (.45) .35 (.49)
.65 (.49) .48 (.51) .13 (.34)
SD given in parentheses. Note: Analyses were performed using children’s raw scores (out of 3), proportions are shown for ease of interpretation.
mophone (denotation-1 present) condition performed so poorly, we excluded this condition from the analysis.3 A 2 (condition: homophone [denotation-1 absent], nonce word) by 3 (information given: no information, theory-based, perceptual) repeated measures MANOVA was used to examine the effect of information given. The analysis showed a significant effect of condition [F(1, 47) ⫽ 15.25, p ⬍ .001] and a significant effect of information (Wilks’ Lambda ⫽ .847, F(2, 46) ⫽ 4.17, p ⬍ .05), but no significant interaction. A planned contrast showed that children were significantly more likely to choose the correct answer when given theory-based information than when given perceptual information [F(1, 47) ⫽ 8.38, p ⬍ .01]. The no-information stories were not significantly different from either of the other two types. Thus, it seems that children can use theory-based information to infer word meaning. We then examined whether there were any information differences for the stories in which both the primary and secondary senses of the homophones referred to inanimates. Because each child heard only one of these stories with each information type, the mean proportion of items correctly answered (shown in Table 4, bottom half) is identical to the proportion of children answering the items correctly. To analyze whether there was an association between information given 3An analogous analysis including the homophone (denotation-1 present) condition yielded similar results: significant effects of condition [F(2,70) ⫽ 60.73, p ⬍.001], information (Wilks’ Lambda ⫽ .888, F(2,68) ⫽ 4.29, p ⬍.05), and a significant condition by information interaction (Wilks’ Lambda ⫽ .866, F(4, 136) ⫽ 2.53, p ⬍.05). In the homophone (denotation-1 present) condition children performed poorly and showed little ability to use theory-based information. A second difference was that the 2 (condition) by 3 (information given) by 3 (datasheet) MANOVA yielded the significant effects discussed above and a trend for the Information by Condition by Questionnaire interaction. This trend was due mainly to means and variances of zero in several cells in the homophone (denotation-1 present) condition.
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and correct answers, we counted the number of children responding correctly vs. incorrectly to each type of information for each condition and submitted these scores to a 3 (condition: nonce, homophone (denotation-1 absent), homophone (denotation-1 present)) ⫻ 3 (information type: no information, theory-based, perceptual) ⫻ 2 (answer: right, wrong) loglinear analysis. The only significant association was the condition by answer association (G2 (2) ⫽ 14.926, p ⬍ .001), indicating that children were more likely to answer correctly when a homophone was not present. In particular there was no answer by information association (p ⬎ .10), indicating no facilitating effect of any particular type of information. Given this result and considering the proportions listed in Table 4, it seems that when the meanings did not cross the animate-inanimate boundary, perceptual information was at least as effective as theory-based information. As theory-based information should only help children when the senses cross domain boundaries, this result was expected. Finally, we examined the data for item effects. This analysis allows us to examine whether the results held across items in general, or were due to the characteristics of one or two items. Moreover, to the extent that the results hold across items, we can eliminate the possibility that the results were caused by the selection of individual distractors. Because of children’s poor performance in the homophone (denotation-1 present) condition, only the homophone (denotation-1 absent) and nonce word conditions were considered for this analysis. In order to examine item differences, we counted the number of times each item was answered correctly when children were given no-information stories, theory-based information stories, and perceptual information stories in each condition. These numbers were converted into proportions to account for the fact that the number of children given each type of information for each item was not exactly equal, although as discussed in the methods section it was approximately equal (e.g., at worst 10, 8, and 8 children in the nonce word condition). We then treated the items as random factors (Clark, 1973). If the effects generalize across items, we should see the same pattern of results when items are treated as random factors as we did in the main analyses in which subjects were treated as random factors. Thus, we used paired t-tests to compare the number of times the six homophones that crossed domain boundaries were answered correctly in the various information conditions (see the preceding analysis for justification of this strategy). In the nonce word condition, there was a significant difference between the theorybased information and the perceptual information (t(5) ⫽ 2.433, one-tailed p ⬍ .05). There were no differences in either of the other two conditions. Note that this replicates the findings concerning information for the nonce word condition and again suggests that hearing a homophone may impede children’s ability to use their knowledge to induce word meanings even when the homophone is not present. Thus, again it seems that children find theory-based information helpful when inducing word meanings; in the nonce condition the results hold across items and are not due to anomalous performance on one or two items.
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DISCUSSION This experiment replicates previous findings (Beveridge & Marsh, 1991; Campbell & Macdonald, 1983; Mazzocco, 1997) that when a picture representing the primary sense of a homophone is present, children have difficulty realizing that the secondary sense of a homophone is being introduced. Even though the wording of the question specifically asked for the homophone “in the story,” children overwhelmingly chose the primary denotation when it was present. In contrast, children were readily able to identify the correct referent when a nonce word was used instead of a homophone. This result suggests that it was not the stories themselves or a general inability to use contextual information, but rather the presence of the homophone and its primary denotation that led to children’s failure. Moreover, when the children’s choices did not include a picture representing the primary sense of the homophone, they were able to identify the correct referent at greater than chance levels, though not as accurately as in the nonce word condition. This finding suggests that simply hearing the homophone impedes children’s performance compared to the nonce word condition. However, in the case in which a referent of the primary sense of the homophone is not available, children are sometimes willing and able to use the context to induce the correct sense. As mentioned above, children induced word meanings more accurately in the nonce word condition than in either homophone condition. Given that the homophones were chosen so that the primary sense was known to the children, this performance drop is not surprising. In the case of the homophone (denotation-1 absent) condition, children’s drop in performance compared to the nonce word condition suggests that the primary sense of the homophone was activated and led to interference. In the case of the homophone (denotation-1 present) condition, it seems that in the presence of the primary sense children either do not recognize or are willing to ignore inconsistencies in the text. Hence, these results help to explain an inconsistency in the literature—why researchers have had difficulty teaching homophones (Mazzocco, 1997) although 3-year-olds know quite a few homophones (Backscheider & Gelman, 1995). In real world learning contexts, referents for both senses of the homophone are rarely present at a single time, increasing the likelihood that children recognize that the homophone denotes a second meaning. It is also possible that in real world situations the primary sense is not always activated when context makes the secondary sense clear. When both denotations are present, as has been the case in previous research, preschoolers may need explicit support. For example, children may need adults to draw a comparison as Kohn and Landau (1990) found parents do for toddlers in natural settings (e.g., “That’s a skate-fish”). Note that these types of expansions may serve to highlight relevant domain information, supporting and employing children’s notions of what kinds of properties are particularly important. These results also suggest that in some situations children may be able to use information regarding animacy to induce word meaning. One potential concern,
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however, is whether these results are due to a tendency for children to point to an animate object when confused. If the results were simply due to a bias to point to an animate when confused, children should do significantly worse when the stories refer to an inanimate object contrasted with animates. Instead, this condition was not significantly different from the other two. Thus, a simple animacy response bias does not explain the present results. Overall, although preschoolers were not able to disregard the primary denotation of the homophones when it was available, children were able to use their knowledge about the animate-inanimate distinction and use properties indicative of the ontological kind of the items to induce the referents of nonce words and homophones when primary denotations were unavailable. These results are especially impressive given that children of this age do not yet reason consistently about biological phenomena (Carey, 1995). In addition, these results indicate that even very young children are using what they know about animates and about biological properties in everyday tasks such as word learning and story comprehension, not simply when they are asked directly about biological properties. The salience of the theory-based information is especially striking given that the information was not directly depicted in the drawings, whereas the perceptual information was more directly depicted (but was used less frequently). The present study has some limitations. Because all stories began with properties and settings intended to alert children that the primary sense was not intended, the information conditions were not pure. That is, theory-based information was initially provided in all stories. Given the difficulty that children have shown learning homophones in the past, stories were constructed to provide several pieces of relevant information quickly. This tactic was taken to maximize opportunities for the children to realize that a secondary interpretation was needed. However, this resulted in a comparison of how children were able to use different types of information presented, in addition to that given in the first sentence of the story. The results indicate that multiple pieces of theory-based information are more useful to children than either a combination of theory-based and perceptual information or a single piece of theory-based information. Moreover, although we classified properties as theoretical or perceptual, in real-world objects these properties are interrelated. Properties were considered theoretical if they distinguished animate from inanimate objects and supported inductions on one or the other of these kinds. In fact, most theory-based properties distinguished living things from human-made objects. Perceptual properties explicitly referred to the appearance of the items. The properties used in this experiment were distinct with regard to these criteria; however, theoretical and perceptual properties are not mutually exclusive. Many theoretical properties require perceptual counterparts. For example, being made of steel (theoretical) requires a certain appearance. Similarly, many perceptual properties suggest theoretical ones. For example, animals are rarely shiny and smooth (perceptual) because of
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their internal and bodily composition (theoretical). Therefore, to call a property purely perceptual or purely theoretical is an oversimplification. Also, given that perceptual information, but not other types of information, was reflected in the line drawings, it is curious that children were not more accurate when given additional perceptual information. We interpret this result as underscoring the relative importance of theory-based information. However, it is possible that children’s performance would have improved if photographs rather than line drawings had been used, because photographs might have increased the relevance of the perceptual information to the children. However, even in the line drawings many perceptual features were available and all items were chosen to be familiar to the children (with familiar perceptual properties). Overall, this experiment indicates that children are able to make use of sophisticated information when reasoning about the meanings of nonce words and, in some situations, homophones. When both the context of the story and the available referents support a secondary interpretation, children are able to use the given contextual information to grasp secondary meanings. However, this ability breaks down in difficult situations; for example, when a secondary interpretation is necessary but a primary denotation is available. In these cases children need more contextual support than has been available in experimental situations. On the other hand, in less complicated situations, children are able to make use of at least one distinction that adults find important: the animate-inanimate distinction. Furthermore, children are able to exploit information about the properties that signal an entity’s status as an animate, living kind or as a human-made object.
REFERENCES Backscheider, A. G., & Gelman, S. A. (1995). Children’s understanding of homonyms. Journal of Child Language, 22, 107–127. Beveridge, M., & Marsh, L. (1991). The influence of linguistic context on children’s understanding of homophonic words. Journal of Child Language, 18, 459–467. Campbell, R. N., & Macdonald, T. B. (1983). Text and context in early language comprehension. In M. Donaldson, R. Grieve, & C. Pratt (Eds.), Early childhood development and education (pp. 115–126). New York: Guilford Press. Carey, S. (1977). The child as word learner. In M. Halle, J. Bresnan, & G. A. Miller (Eds.), Linguistic theory and psychological reality (pp. 264–293). Cambridge, MA: Cambridge University Press. Carey, S. (1985). Conceptual change in childhood. Cambridge, MA: MIT Press. Carey, S. (1995). On the origin of causal understanding. In D. Sperber, D. Premack, & A. J. Premack (Eds.), Causal cognition: A multidisciplinary debate (pp. 268–308). Oxford: Clarendon Press. Clark, H. H. (1973). The language-as-fixed-effect fallacy: A critique of language statistics in psychological research. Journal of Verbal Learning and Verbal Behavior, 12, 335–359. Gelman, R., Durgin, F., & Kaufman, L. (1995). Distinguishing between animates and in-
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animates: Not by motion alone. In D. Sperber, D. Premack, & A. J. Premack (Eds.), Causal cognition: A multidisciplinary debate (pp. 150–194). Oxford: Clarendon Press. Gelman, S. A. (1988). The development of induction within natural kind and artifact categories. Cognitive Psychology, 20, 65–95. Gelman, S. A., & Coley, J. D. (1990). The importance of knowing a dodo is a bird: Categories and induction in two-year-olds. Developmental Psychology, 26, 796–804. Gelman, S. A., & Markman, E. M. (1987). Young children’s induction from natural kinds: The role of categories and appearances. Child Development, 58, 1532–1541. Inhelder, B., & Piaget, J. (1964). The early growth of logic in the child. NY: Norton. Keil, F. C. (1989). Concepts, kinds, and cognitive development. Cambridge, MA: MIT Press. Keil, F. C. (1992). The origins of autonomous biology. In M.R. Gunnar & M. Maratsos (Eds.), Modularity and constraints in language and cognition. Hillsdale, NJ: Erlbaum. Kohn, A., & Landau, B. (1990). A partial solution to the homonym problem: Parents’ linguistic input to young children. Journal of Psycholinguistic Research, 19, 71–89. Lyons, J. (1977). Semantics, Volume I. New York: Cambridge University Press. Mandler, J. M. (1992). How to build a baby II: Conceptual primitives. Psychological Review, 99, 587–604. Markman, E. M. (1989). Categorization and naming in children. Cambridge, MA: MIT Press. Massey, C. & Gelman, R. (1988). Preschooler’s ability to decide whether a photographed unfamiliar object can move itself. Developmental Psychology, 24, 307–317. Mazzocco, M. M. (1997). Children’s interpretation of homonyms: A developmental study. Journal of Child Language, 24, 441–467. Quine, W. V. O. (1960). Word and object. Cambridge, MA: MIT Press. Rosengren, K. S., Gelman, S. A., Kalish, C. W., & McCormack, M. (1991). As time goes by: Children’s early understanding of growth in animals. Child Development, 62, 1302–1320. Springer, K. (1995). Acquiring a naïve theory of kinship though inference. Child Development, 66, 547–558. Wellman, H. M. & Gelman, S. A. (1992). Cognitive development: Foundational theories of core domains. Annual Review of Psychology, 43, 337–375. Wellman, H. M. & Gopnik, A. (1994). The theory theory. In L. A. Hirschfeld & S. A. Gelman (Eds.), Mapping the mind: Domain specificity in cognition and culture (pp. 257–293). New York, NY: Cambridge University Press.
© 2000 Elsevier Science Inc. All rights of reproduction reserved.
Children’s Use of Different Information Types When Learning Homophones and Nonce Words Andrea G. Backscheider University of Houston, Houston, TX, USA
Susan A. Gelman Ivelisse Martinez University of Michigan, Ann Arbor, MI, USA
Jennifer Kowieski University of Notre Dame, South Bend, IN, USA This study examines whether 3-year-olds are able to use ontological distinctions in homophone and nonce word acquisition. In the homophone (denotation-1 present) condition, children heard stories introducing second meanings of homophones; for example, a skate (i.e., fish). Stories contained perceptual information, information about theory-based properties, or filler material. Children identified the referent from 3 drawings depicting the familiar meaning, the secondary meaning, and a distractor. In the homophone (denotation-1 absent) condition, the picture of the familiar meaning was replaced with a distractor. The nonce word condition, a control condition, was identical to the homophone (denotation-1 present) condition except that a nonce word replaced the homophone. Children were rarely able to construct a sec-
This work was supported in part by a National Science Foundation Predoctoral Fellowship to Andrea Backscheider and a J. S. Guggenheim Fellowship and NICHD grant HD36043 to Susan Gelman. Portions of this work were presented the 1997 Biennial Meeting of the Society for Research in Child Development, Washington, D. C. We would like to thank the children, parents, and staff of Friends School, Tutor Time Learning Center, Red Barn Learning Center, and the Shamrock School of South Bend, and the University of Michigan Children’s Centers for their participation in this research. We would like to thank Cari McCarty, Chris Kubischek, Sarah Tschaen, Yvette Ramirez, and Jennifer Mullins for their helpful comments and their assistance in data collection. We would also like to thank two anonymous reviewers for their helpful comments. Direct all correspondence to: Andrea G. Backscheider, Department of Educational Psychology, University of Houston, Houston, TX 77204; E-mail: [email protected] Manuscript received September 26, 1997; revision accepted June 21, 1999
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ond homophone interpretation when the familiar denotation was available. Interestingly, in the remaining conditions, children used information about the animate-inanimate distinction in choosing the referent. We discuss children’s use of this ontological distinction when inducing word meaning.
When children hear a new word, their task of mapping the unfamiliar word to a referent is not a trivial one. Children must determine the word meaning from an infinite number of possibilities (Quine, 1960). In the case of learning second meanings1 of homophones, the task is even more difficult. Children must not only isolate the correct meaning from the context, but also realize that a familiar phonological pattern does not map to the accustomed meaning. For example, a child who has only heard the word “bat” refer to a piece of sports equipment will at some point hear “bat” denoting a flying mammal. In order to map “bat” correctly to the new meaning, the child must realize that (a) the familiar pattern of sounds is not being used to denote a baseball bat, and also that (b) it denotes a flying mammal. Mapping a novel word to a referent is a task at which young children excel (Carey, 1977; Markman, 1989); however, mapping a homophone to its secondary meaning seems to pose a problem for children during the preschool and elementary school years. Although Backscheider and Gelman (1995) found that 3-year-olds can identify both meanings of some common homophones even when both denotations are presented together, other researchers have had little success teaching children second meanings of known words. Campbell and Macdonald (1983) found that 3- to 5-year-old children tend to interpret novel homophones presented in context as having the meaning which is most familiar to them, even when this meaning is not consistent with the information presented in the context. Similarly, Beveridge and Marsh (1991) investigated the role of context in children’s ability to determine the secondary meaning of a homophone. The experimenter read 3- to 6-year-olds stories incorporating the secondary meanings of homophones. Some stories included elaborated contexts; that is, increased perceptual and functional information. Although the elaborated context helped children realize that the homophone denoted the secondary meaning, even when this context was present 3-year-olds chose the secondary denotation on only 18% of the trials, and 6-year-olds chose correctly on only 42% of the trials. Finally, Mazzocco (1997) found that preschoolers and second graders were less able to use context to interpret pseudo-homonyms (familiar English words used as hom-
1Throughout this paper, the term “meaning” is used to refer to the sense of the homophone. Thus, when we say that young children do not know the secondary meaning, we assert that although the children are familiar with the primary sense of the homophone, they are not yet familiar with the secondary sense. The term “denotation” is used to refer to the class of potential referents (see Lyons, 1977).
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onyms in the experiment) than to interpret novel words. Thus, the literature indicates that although children do know some homophones, it is difficult to teach second meanings of known words. How then, if children have difficulty learning the second meanings, do 3-year-olds know so many homophones? In this research, we manipulate several factors to examine children’s acquisition of new words and second meanings of familiar words. First, the present research examines the effect of context on children’s performance. Campbell and Macdonald (1983) found that children often failed to use context to determine the meaning of homophones, and Beveridge and Marsh (1991) found that although children performed better with elaborated context, children certainly had difficulty using context to determine word meanings. However, one question that has not been examined is what type of context helps children realize that a known word has a second sense. In this research, we examine whether different types of information help children determine the secondary senses of homophones. Specifically, we examine (i) the effect of information about the perceptual properties of the objects (perceptual information) and (ii) what we will refer to as theorybased information. In this way the present experiment examines whether certain types of information are particularly useful in helping children induce the meaning of homophones and nonce words (that is, nonsense word forms referring to the secondary denotation of the homophone). Piagetian theory (Inhelder and Piaget, 1964) suggests that preschoolers should be able to use perceptual information, but not information relying on more abstract properties. In contrast, recent research has indicated that children may build “naïve theories” to reason about the world (Wellman & Gelman, 1992; Wellman & Gopnik, 1994). These theories are coherent, domain-specific causalexplanatory frameworks that allow children to reason in a consistent, but not necessarily adultlike, fashion. Thus, children may use a naïve physics to reason about object motion and a naïve psychology to reason about human behavior. There is more debate about whether preschoolers reason according to biological principles, but there is some consensus that preschoolers are learning about biological phenomena (such as growth) during the preschool years (Carey, 1985, 1995; Wellman & Gelman, 1992; Keil, 1992; Springer, 1995) and that they recognize the animate-inanimate distinction (Gelman, Durgin, & Kaufman, 1995; Massey & Gelman, 1988). Moreover, S. Gelman and her colleagues have found that young preschoolers appreciate that nonobvious properties are important in reasoning about natural kind categories (Gelman, 1988; Gelman & Coley, 1990; Gelman & Markman, 1987), suggesting that they may find information about nonperceptual properties useful. Taken together, previous research suggests that although 3-year-olds may not yet hold a naïve biological theory, the properties that will later constitute this theory hold a privileged place in their reasoning. Thus, stories that emphasize these properties may give children cues to set up a second meaning for a known word. In addition, given that from an early age children pay particular attention to the
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features that distinguish animates from inanimates (Mandler, 1992; Gelman, Durgin, & Kaufman, 1995), children may be better able to learn homophones when their first and second meanings cross this ontological boundary. Simply, children may be more likely to realize that a word has a second meaning when the new meaning is ontologically distinct from the familiar meaning. For example, children may have an easier time learning homophones such as bat, where one meaning refers to an animate and one to an inanimate, than bow, where both meanings refer to inanimates. Second, in the case of homophones we specifically manipulate the availability of the primary meaning as a response. In previous research, the situations that children faced were very different from what they might face in a natural setting. In Campbell and Macdonald’s (1983) research, children were asked to complete a drawing (e.g., they were asked to add the old “wing of the castle” to a partially drawn castle) after hearing a story; thus, although some context was provided, neither denotation of the homophone was present at the time the story was read. In a more natural setting, at the time that a new object term or homophone is introduced to a preschooler, the referent is likely to be present in the environment. In Beveridge and Marsh’s (1991) and Mazzocco’s (1997) research, after hearing the story children were asked to choose the homophone from pictures containing both the primary and secondary meanings. However, in most natural situations it seems likely that when preschoolers hear a homophone used in its secondary sense, the intended referent will be present and supported by the context whereas a referent consistent with the known, primary sense will not be present. For example, a baseball bat is unlikely to be present with a mammal-bat, and a bow (and arrow) is unlikely to be present with a hair bow. Therefore, children’s failure in these studies may be due less to an inability to use context to determine that the homophone refers to a second meaning than to an inability to inhibit the first meaning. Children may prove more able to assign a second meaning to a word when a referent for the familiar meaning is not available. Thus, in the following experiment we examine the effect of context and response set on children’s acquisition of homophones and nonce words. We hypothesize that children will be better able to identify the secondary denotation of a homophone when the primary denotation is not available. In addition, we investigate whether children find either theory-based or perceptual information particularly useful in isolating word meanings, and whether children are able to make use of the animate-inanimate distinction.
METHOD Participants Seventy-two 3- and 4-year-olds participated in the main experiment: 26 children in the nonce word condition (range ⫽ 3;1 to 4;1, M ⫽ 3;8, 14 girls and 12
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boys), 23 children in the homophone (denotation-1 present) condition (range ⫽ 3;0 to 4;6, M ⫽ 3;9, 14 girls and 9 boys), and 23 children in the homophone (denotation-1 absent) condition (range ⫽ 3;0 to 4;4, M ⫽ 3;8, 12 girls and 11 boys). All children were drawn from preschools serving a small midwestern city. Children were primarily middle-class and of European-American descent. American English was the first language of all children. Two additional children were eliminated because they answered a control story incorrectly. In addition, 12 children (range ⫽ 3;1 to 4;1, M ⫽ 3;7, 7 girls and 5 boys) participated in pilot testing of the items. Materials and design Nine homophones were selected. All homophones were English words or the first half of compound nouns (e.g., milk for milk snake). Homophones were selected such that for three homophones the primary sense (i.e., those already known) denoted inanimate items and the secondary sense (i.e., the meanings children were taught) denoted animate items (Inanimate/Animate items; e.g., skate: footwear/fish); for three homophones the primary sense denoted an animate item and the secondary sense denoted an inanimate item (Animate/Inanimate items; e.g., fox: animal/sword); and for three homophones both senses denoted inanimate objects (Inanimate/Inanimate items; e.g., log: piece of wood/diary).2 This selection allowed investigation of whether children are sensitive to domain differences in a word-learning task; that is, whether children are better able to isolate second senses when the meanings cross ontological boundaries than when the two senses denote objects in the same domain. The homophones are listed in Table 1. To examine the effect of information type, three stories were constructed for each homophone. Because previous research has shown that children have difficulty learning second senses for homophones, all stories contained several pieces of contextual information designed to alert children that the primary sense of the homophone was inappropriate. All stories began with the same first sentence, the constant information, but diverged at the second sentence, which contained the different types of information. The first sentence of the stories introduced the item and gave a property and setting diagnostic of the secondary sense but inconsistent with the primary sense (e.g., “the drill (snail) crawled beside the pond”). For the animates, these sentences described an animal doing something; for the inanimates, the first sentence described a person using the object for a purpose. Thus, these sentences set up situations that we hoped would alert the child that the word was being used in an unusual way; the following sentences would then give addi2Homophones were selected through a pilot study in which twelve 3- and 4-year-olds served as participants. All primary meanings were recognized by at least 11 participants; no secondary meanings were identified. Additionally, all children produced correct names (though not the homophones) for pictures of the secondary meanings.
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Table 1. List of Homophones Taught, Constant Information, Theory-Based Information, and Perceptual Information Homophone/ meaning Inanimate– animate Skate/fish Milk/snake Drill/snail Animate– inanimate Monkey/ jackhammer Fox/sword Buffalo/coat Inanimate– inanimate Log/diary
Constant information
Distinctive information given No-info
Theory-based
Perceptual
Swimming in ocean Frightened child Crawls by pond
Going to island
Eats
Is very large
Child ran to mom Was dry
Crawls Has children
Has stripes Has black spots
Used to break cement King carries to battle Worn for warmth
Job was hard
Is made of steel Has a blade
Is silver/heavy
Explorer got in Alaska
Has buttons
Is very long
Written in
Has pages
Is cooked
Has blue/red lettering Has curved top/ flat bottom Has white bottoms/ green tops
With king always
Plane/tool
Smooths wood
Writing about storm Kept in basement
Leak/leek
For dinner
Also had chicken
Is a tool
Is shiny/smooth
tional evidence that a new interpretation was necessary. As a result of this tactic, many of the properties given in the first sentence were theory-based (see below). However, this design should work against our hypothesis that there would be condition effects. To the extent that we find an effect of theory-based information, it is despite the conservative design of the study. Stories then continued with a second piece of information. In the perceptual information stories, the information concerned the appearance of the object (e.g., that the drill had black spots). In the no-information stories, children were given irrelevant information (e.g., that it had rained recently but the drill was dry). In the theory-based information stories, information included properties that previous research has suggested children are familiar with (Keil, 1989; Massey & Gelman, 1988; Rosengren, Gelman, Kalish, & McCormack, 1991; Wellman & Gelman, 1992) and that are likely to be present in children’s developing theories (Wellman & Gelman, 1992). These properties differentiate animates from inanimates and support category-based reasoning. For animates the properties used included growth, self-generated movement, and reproduction (e.g., that the drill had children), and for inanimates properties concerned parts and composition
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(e.g., that the monkey [jackhammer] was made of steel). Note that for the homonyms that did not cross domain boundaries, giving theory-based information that differentiated animates from inanimates does not help children determine the correct referent. Therefore, in these cases we gave information about function or superordinate category. For each homophone, the three stories were constructed to contain approximately the same number of words and syllables. See Table 1 for a list of properties. From the sets of homophones and stories, six datasheets containing different sets of stories were constructed. On each datasheet every homophone appeared exactly once in exactly one information condition. Across datasheets, each homophone appeared equally often in each information condition. For example, one-third of the datasheets contained the perceptual story for skate, one-third contained the theory-based story, and one-third contained the no-information story. Across homophones, each datasheet contained 3 perceptual stories, 3 theory-based stories, and 3 no-information stories. Thus, both the information type and domain comparisons were within-subject comparisons. For each homophone, a set of four line drawings was constructed. This set was paired with the homophone regardless of story type; that is, it was used for no-information, perceptual, and theory-based stories. One drawing depicted the primary sense of the homophone, one the secondary sense of the homophone, and two depicted distractors (see Table 2). We included distractors to eliminate the possible response strategy of choosing the only drawing that did not depict the familiar denotation. In order to allow children to use information regarding the animacy status of the items to choose the correct drawing, the distractors were chosen to be unrelated objects from the domain (animate or inanimate) of the primary sense of the homophone. Additionally, because previous research has shown that children have difficulty realizing that a speaker is using a known homophone in its secondary sense, distractors were chosen to be familiar to chil-
Table 2.
List of Homophones and Distractors
Homophone Inanimate–animate Skate Milk Drill Animate–inanimate Monkey Fox Buffalo Inanimate–inanimate Log Plane Leek
Distractor 1
Distractor 2
Purse Banana Lamp
Ice cream cone Kite Bow
Dog Fish Bird
Giraffe Bug Frog
Toothpaste Car Jug
Bike Ball Comb
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dren but clearly not intended referents of the story. Distractors were chosen to be familiar to eliminate the possibility that children would choose distractors because they were the only items for which the children did not have a name. Furthermore, in order to ease the processing demands on the children in an already difficult task, the distractors were chosen such that they were clearly not possible referents of the story. All items were pictured without a setting; for example, the drawing depicting the primary meaning of skate was a single roller skate on a white background. Thus, the constant information was not provided in any of the pictures. The theory-based information also was not depicted in the drawings; for example, living things were not shown eating or in motion. In contrast, perceptual information was represented to the extent possible in the drawings. In each set, the drawing of the secondary sense reflected the perceptual property given in the story (for example, the snail-drill had black spots), and the drawing of the familiar sense did not reflect the property. In addition, 3 control stories and picture sets were constructed. These stories concerned common items (not homophones) such as scissors. Procedure A familiar experimenter took children to a quiet corner of their classroom. Each child was randomly assigned to one datasheet with the constraint that datasheets were distributed such that each homonym was heard in each information condition with approximately equal frequency. The experimenter told the children that they would listen to some stories, then help the experimenter find the things in the stories. The first story was always a control story in which children were told about a common item such as scissors, and were then asked to find the scissors from the set of three pictures. In this example a picture of scissors was paired with two distractors. Then, children were presented with the nine experimental items and remaining control items in random order. In the homophone (denotation-1 present) condition, the experimenter read each story and showed the child the set of three line drawings from the picture set: the primary meaning, the secondary meaning, and the first distractor. The experimenter then asked the child, “Which one is the [homophone] that’s in the story?” For example, after reading the story about the drill, children were asked, “Which one is the drill that’s in the story?” If children indicated confusion or refused to choose, the experimenter reread the story and encouraged the child to make a best guess. The nonce word and homophone (denotation-1 absent) conditions were virtually identical to the homophone (denotation-1 present) condition. In the nonce word condition, however, the homophone was replaced by a nonce word modeled after the Spanish counterparts but with American English pronunciation: For example, the word “drill” was replaced with “caracol.” In the homophone (denotation-1 absent) condition the homophone was used, but the picture of the famil-
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iar meaning of the homophone was replaced by the second distractor (see the materials section). Thus, in this condition the primary meaning of the homophone was not available to the child as a choice. In all conditions, the left-to-right placement of the pictures was randomized.
RESULTS Preliminary analyses showed no effect of gender or datasheet; therefore these factors were excluded from the remaining analyses. The first analysis compares the number of correct responses (the secondary denotation of the homophone) given by the children in the homophone (denotation-1 present), homophone (denotation-1 absent), and nonce word conditions. A one-way analysis of variance (ANOVA) using the total number of correct pictures chosen showed a significant main effect of condition [F(2, 69) ⫽ 51.08, p ⬍ .001]. Tukey HSD tests indicated that children were significantly more likely (p ⬍ .001) to choose the correct picture in the homophone (denotation-1 absent) condition (M ⫽ 4.22 out of 9 correct, or 47%) than in the homophone (denotation-1 present) condition (M ⫽ 1.30 out of 9 correct, or 14%). In the homophone (denotation-1 present) condition, children chose the primary denotation of the homophone on 75% of the trials. Children were also significantly more likely to choose the correct homophone in the nonce word condition (M ⫽ 5.69 out of 9 correct, or 63%), than in either of the other conditions (p’s ⬍ .005). Note here that 3-year-olds had some difficulty finding the referent of the novel words. We next compared children’s performance to chance levels. Children were significantly less likely than chance (33%) to choose the correct picture in the homophone (denotation-1 present) condition (t (22) ⫽ 5.46, p ⬍ .001) and more likely than chance to choose the correct picture in the homophone (denotation-1 absent) and nonce word conditions (t’s ⬎ 3.28, p’s ⬍ .005). Hence, it is clear that the presence of a denotation for the familiar, primary sense interferes with children’s ability to choose a picture representing the secondary sense. Moreover, even when the familiar denotation is excluded as a choice, the presence of a homophone interferes with children’s ability to process the story and induce the correct word meaning. We then examined the effect of whether the homophone senses crossed the animate-inanimate domain boundary on children’s ability to choose a denotation of the secondary sense. For each child, we computed three scores: The number of animate-inanimate stories (primary meaning is an animate, secondary is an inanimate) answered correctly, the number of inanimate-animate stories answered correctly, and the number of inanimate-inanimate (no boundary crossed) stories answered correctly (see Table 3). A 3 (condition: homophone (denotation-1 present), homophone (denotation-1 absent), nonce word) by 3 (boundary crossed: animate-inanimate, inanimate-animate, inanimate-inanimate) repeated measures
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Table 3. Mean Proportion Correct for Stories that Crossed and Did Not Cross the Animate/Inanimate Domain Boundary Primary/secondary homophone sense Condition Nonce word Homophone (deont.-1 absent) Homophone (denot.-1 present)
Inanimate/animate Animate/inanimate Inanimate/inanimate .72 (.32) .54 (.34) .10 (.18)
.64 (.25) .45 (.29) .09 (.25)
.54 (.25) .42 (.23) .22 (.26)
SD given in parentheses. Note: Analyses were performed using children’s raw scores (out of 3), proportions are shown for ease of interpretation.
MANOVA indicated a main effect of condition [F(2, 69) ⫽ 54.23, p ⬍ .001] and a significant Condition ⫻ Boundary Crossed interaction (Wilks’ Lambda ⫽ .860, F(4, 136) ⫽ 2.66, p ⬍ .05). The main effect of condition indicates that, as discussed above, children were less likely to choose the correct answer when homophones were present. Post-hoc contrasts investigating the interaction indicated that children’s responses in the homophone (denotation-1 present) condition followed a different pattern from the nonce word and homophone (denotation-1 absent) conditions [F(2, 68) ⫽ 5.09, p ⬍ .01]. However, there was no significant difference between the pattern of children’s responses in the homophone (denotation-1 absent) and nonce word conditions (p ⬎ .10). In the homophone (denotation-1 present) condition, there was no effect of whether a domain boundary was crossed, as children were consistently performing poorly. In the remaining two conditions, planned comparisons indicated that children were better able to choose the correct picture when the story referred to an animate that was contrasted with inanimates than when the story concerned an inanimate contrasted with other inanimates (Bonferroni t(48) ⫽ 2.76, p ⬍ .05). Children’s percent correct on the stories contrasting inanimates with animates was not different from either of the other story types. Thus, there is some evidence that children are able to use information differentiating animates from inanimates when reasoning about word meanings. Last, we examined the effect of information type on children’s ability to choose the secondary meaning. Because theory-based information was designed to give children information about the animacy status of the items, this type of domain-specific information could only aid children’s reasoning when the senses of the homophones cross the animate/inanimate boundary. Thus, we eliminated the inanimate/inanimate stories from this analysis but analyzed them separately in a subsequent analysis. From the animate/inanimate and inanimate/animate stories where this boundary is relevant, we computed three scores for each child: The number of perceptual information stories answered correctly, the number of theory-based stories answered correctly, and the number of no-information stories answered correctly (see Table 4). In addition, because the children in the ho-
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Table 4. Mean Proportion Correct for Each Type of Information Given for Stories that Crossed and Did Not Cross the Animate/Inanimate Domain Boundary Information type Story type, with conditions Domain boundary crossed Nonce word Homophone (denot.-1 absent) Homophone (denot.-1 present) Domain boundary not crossed Nonce word Homophone (denot.-1 absent) Homophone (denot.-1 present)
No-information
Theory-based
Perceptual
.67 (.45) .46 (.33) .13 (.27)
.79 (.38) .54 (.37) .04 (.14)
.58 (.27) .48 (.32) .11 (.26)
.46 (.51) .52 (.51) .21 (.42)
.50 (.51) .26 (.45) .35 (.49)
.65 (.49) .48 (.51) .13 (.34)
SD given in parentheses. Note: Analyses were performed using children’s raw scores (out of 3), proportions are shown for ease of interpretation.
mophone (denotation-1 present) condition performed so poorly, we excluded this condition from the analysis.3 A 2 (condition: homophone [denotation-1 absent], nonce word) by 3 (information given: no information, theory-based, perceptual) repeated measures MANOVA was used to examine the effect of information given. The analysis showed a significant effect of condition [F(1, 47) ⫽ 15.25, p ⬍ .001] and a significant effect of information (Wilks’ Lambda ⫽ .847, F(2, 46) ⫽ 4.17, p ⬍ .05), but no significant interaction. A planned contrast showed that children were significantly more likely to choose the correct answer when given theory-based information than when given perceptual information [F(1, 47) ⫽ 8.38, p ⬍ .01]. The no-information stories were not significantly different from either of the other two types. Thus, it seems that children can use theory-based information to infer word meaning. We then examined whether there were any information differences for the stories in which both the primary and secondary senses of the homophones referred to inanimates. Because each child heard only one of these stories with each information type, the mean proportion of items correctly answered (shown in Table 4, bottom half) is identical to the proportion of children answering the items correctly. To analyze whether there was an association between information given 3An analogous analysis including the homophone (denotation-1 present) condition yielded similar results: significant effects of condition [F(2,70) ⫽ 60.73, p ⬍.001], information (Wilks’ Lambda ⫽ .888, F(2,68) ⫽ 4.29, p ⬍.05), and a significant condition by information interaction (Wilks’ Lambda ⫽ .866, F(4, 136) ⫽ 2.53, p ⬍.05). In the homophone (denotation-1 present) condition children performed poorly and showed little ability to use theory-based information. A second difference was that the 2 (condition) by 3 (information given) by 3 (datasheet) MANOVA yielded the significant effects discussed above and a trend for the Information by Condition by Questionnaire interaction. This trend was due mainly to means and variances of zero in several cells in the homophone (denotation-1 present) condition.
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and correct answers, we counted the number of children responding correctly vs. incorrectly to each type of information for each condition and submitted these scores to a 3 (condition: nonce, homophone (denotation-1 absent), homophone (denotation-1 present)) ⫻ 3 (information type: no information, theory-based, perceptual) ⫻ 2 (answer: right, wrong) loglinear analysis. The only significant association was the condition by answer association (G2 (2) ⫽ 14.926, p ⬍ .001), indicating that children were more likely to answer correctly when a homophone was not present. In particular there was no answer by information association (p ⬎ .10), indicating no facilitating effect of any particular type of information. Given this result and considering the proportions listed in Table 4, it seems that when the meanings did not cross the animate-inanimate boundary, perceptual information was at least as effective as theory-based information. As theory-based information should only help children when the senses cross domain boundaries, this result was expected. Finally, we examined the data for item effects. This analysis allows us to examine whether the results held across items in general, or were due to the characteristics of one or two items. Moreover, to the extent that the results hold across items, we can eliminate the possibility that the results were caused by the selection of individual distractors. Because of children’s poor performance in the homophone (denotation-1 present) condition, only the homophone (denotation-1 absent) and nonce word conditions were considered for this analysis. In order to examine item differences, we counted the number of times each item was answered correctly when children were given no-information stories, theory-based information stories, and perceptual information stories in each condition. These numbers were converted into proportions to account for the fact that the number of children given each type of information for each item was not exactly equal, although as discussed in the methods section it was approximately equal (e.g., at worst 10, 8, and 8 children in the nonce word condition). We then treated the items as random factors (Clark, 1973). If the effects generalize across items, we should see the same pattern of results when items are treated as random factors as we did in the main analyses in which subjects were treated as random factors. Thus, we used paired t-tests to compare the number of times the six homophones that crossed domain boundaries were answered correctly in the various information conditions (see the preceding analysis for justification of this strategy). In the nonce word condition, there was a significant difference between the theorybased information and the perceptual information (t(5) ⫽ 2.433, one-tailed p ⬍ .05). There were no differences in either of the other two conditions. Note that this replicates the findings concerning information for the nonce word condition and again suggests that hearing a homophone may impede children’s ability to use their knowledge to induce word meanings even when the homophone is not present. Thus, again it seems that children find theory-based information helpful when inducing word meanings; in the nonce condition the results hold across items and are not due to anomalous performance on one or two items.
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DISCUSSION This experiment replicates previous findings (Beveridge & Marsh, 1991; Campbell & Macdonald, 1983; Mazzocco, 1997) that when a picture representing the primary sense of a homophone is present, children have difficulty realizing that the secondary sense of a homophone is being introduced. Even though the wording of the question specifically asked for the homophone “in the story,” children overwhelmingly chose the primary denotation when it was present. In contrast, children were readily able to identify the correct referent when a nonce word was used instead of a homophone. This result suggests that it was not the stories themselves or a general inability to use contextual information, but rather the presence of the homophone and its primary denotation that led to children’s failure. Moreover, when the children’s choices did not include a picture representing the primary sense of the homophone, they were able to identify the correct referent at greater than chance levels, though not as accurately as in the nonce word condition. This finding suggests that simply hearing the homophone impedes children’s performance compared to the nonce word condition. However, in the case in which a referent of the primary sense of the homophone is not available, children are sometimes willing and able to use the context to induce the correct sense. As mentioned above, children induced word meanings more accurately in the nonce word condition than in either homophone condition. Given that the homophones were chosen so that the primary sense was known to the children, this performance drop is not surprising. In the case of the homophone (denotation-1 absent) condition, children’s drop in performance compared to the nonce word condition suggests that the primary sense of the homophone was activated and led to interference. In the case of the homophone (denotation-1 present) condition, it seems that in the presence of the primary sense children either do not recognize or are willing to ignore inconsistencies in the text. Hence, these results help to explain an inconsistency in the literature—why researchers have had difficulty teaching homophones (Mazzocco, 1997) although 3-year-olds know quite a few homophones (Backscheider & Gelman, 1995). In real world learning contexts, referents for both senses of the homophone are rarely present at a single time, increasing the likelihood that children recognize that the homophone denotes a second meaning. It is also possible that in real world situations the primary sense is not always activated when context makes the secondary sense clear. When both denotations are present, as has been the case in previous research, preschoolers may need explicit support. For example, children may need adults to draw a comparison as Kohn and Landau (1990) found parents do for toddlers in natural settings (e.g., “That’s a skate-fish”). Note that these types of expansions may serve to highlight relevant domain information, supporting and employing children’s notions of what kinds of properties are particularly important. These results also suggest that in some situations children may be able to use information regarding animacy to induce word meaning. One potential concern,
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however, is whether these results are due to a tendency for children to point to an animate object when confused. If the results were simply due to a bias to point to an animate when confused, children should do significantly worse when the stories refer to an inanimate object contrasted with animates. Instead, this condition was not significantly different from the other two. Thus, a simple animacy response bias does not explain the present results. Overall, although preschoolers were not able to disregard the primary denotation of the homophones when it was available, children were able to use their knowledge about the animate-inanimate distinction and use properties indicative of the ontological kind of the items to induce the referents of nonce words and homophones when primary denotations were unavailable. These results are especially impressive given that children of this age do not yet reason consistently about biological phenomena (Carey, 1995). In addition, these results indicate that even very young children are using what they know about animates and about biological properties in everyday tasks such as word learning and story comprehension, not simply when they are asked directly about biological properties. The salience of the theory-based information is especially striking given that the information was not directly depicted in the drawings, whereas the perceptual information was more directly depicted (but was used less frequently). The present study has some limitations. Because all stories began with properties and settings intended to alert children that the primary sense was not intended, the information conditions were not pure. That is, theory-based information was initially provided in all stories. Given the difficulty that children have shown learning homophones in the past, stories were constructed to provide several pieces of relevant information quickly. This tactic was taken to maximize opportunities for the children to realize that a secondary interpretation was needed. However, this resulted in a comparison of how children were able to use different types of information presented, in addition to that given in the first sentence of the story. The results indicate that multiple pieces of theory-based information are more useful to children than either a combination of theory-based and perceptual information or a single piece of theory-based information. Moreover, although we classified properties as theoretical or perceptual, in real-world objects these properties are interrelated. Properties were considered theoretical if they distinguished animate from inanimate objects and supported inductions on one or the other of these kinds. In fact, most theory-based properties distinguished living things from human-made objects. Perceptual properties explicitly referred to the appearance of the items. The properties used in this experiment were distinct with regard to these criteria; however, theoretical and perceptual properties are not mutually exclusive. Many theoretical properties require perceptual counterparts. For example, being made of steel (theoretical) requires a certain appearance. Similarly, many perceptual properties suggest theoretical ones. For example, animals are rarely shiny and smooth (perceptual) because of
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their internal and bodily composition (theoretical). Therefore, to call a property purely perceptual or purely theoretical is an oversimplification. Also, given that perceptual information, but not other types of information, was reflected in the line drawings, it is curious that children were not more accurate when given additional perceptual information. We interpret this result as underscoring the relative importance of theory-based information. However, it is possible that children’s performance would have improved if photographs rather than line drawings had been used, because photographs might have increased the relevance of the perceptual information to the children. However, even in the line drawings many perceptual features were available and all items were chosen to be familiar to the children (with familiar perceptual properties). Overall, this experiment indicates that children are able to make use of sophisticated information when reasoning about the meanings of nonce words and, in some situations, homophones. When both the context of the story and the available referents support a secondary interpretation, children are able to use the given contextual information to grasp secondary meanings. However, this ability breaks down in difficult situations; for example, when a secondary interpretation is necessary but a primary denotation is available. In these cases children need more contextual support than has been available in experimental situations. On the other hand, in less complicated situations, children are able to make use of at least one distinction that adults find important: the animate-inanimate distinction. Furthermore, children are able to exploit information about the properties that signal an entity’s status as an animate, living kind or as a human-made object.
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