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Changes in Children's Voices
Journal of Voice Vol. 16, No. 4, pp. 530–543 © 2002 The Voice Foundation
Changes in Children’s Voices: The Effect of Cognitive Cues *Todd A. Bohnenkamp, *Moya Andrews, *Rahul Shrivastav, and †Anne Summers *Indiana University, Bloomington, Indiana; †Monroe County Community School Corporation, Bloomington, Indiana
Summary: Variation in duration and frequency during two readings of each of four sentences by 15 normal 9- and 10-year-old children were compared. Instructions to the children included overt cues designed specifically to elicit durational and frequency changes. Children demonstrated increased sentence variability in their voices when they were cued. Specific key words in the four sentences were also analyzed and results indicated that semantic content in addition to parameter-specific cognitive cues provided a significant effect. The male 9 and 10-year-old subjects showed less variability in “no cue” readings than the females, but showed a greater increase in voice change during the “cognitive cue” readings. Implications for theory and practice are discussed. Key Words: Cognitive cueing—Voice therapy—Voice therapy in children.
INTRODUCTION
that are suggested by the written words of a text and also on the speakers’ thoughts and feelings regarding the text. Cues and images of this type have traditionally been used by drama and singing teachers to elicit vocal behaviors, but the use of this technique with children has not been subjected to empirical scrutiny. Previous research has indicated that cognitive cueing is aided by the semantic imagery inherent in the material presented. When a subject is to read from a text, words such as action words (e.g., jump), spatial words (e.g., up and down), and emotive words (e.g., happy, sad) can easily be identified as “picture words.” The experimenter can then provide cues that stimulate thinking about such word pictures. For example, a sentence used in a previous research study: “The submarine sank to the bottom of the sea” was used with the cue “think about the surface of the water; start your voice there and show me how the submarine goes down.”1 This sentence included the embedded semantic cues of downward motion and was presented with specific instructions to speakers to indicate a downward movement of the voice.
Cognitive cueing is an approach to voice treatment that stimulates thought patterns as a way of changing speakers’ voices. Previous studies of cognitive cueing have indicated that this is a promising technique for voice therapy in adults with and without voice disorders.1 In studies of adults, the documented changes in vocal behavior with cognitive cues included an increase in fundamental frequency variation, increased intensity variation, and increased sentence duration.1 Cognitive cueing focuses the attention of the speaker on the actions and images Accepted for publication April 16, 2002. This paper was presented at the 30th Annual Voice Foundation Symposium: Care of the Professional Voice, June 13–17, 2001, Philadelphia, Pennsylvania. Address correspondence and reprint requests to Address correspondence and reprint requests to Moya Andrews, Professor of Speech and Hearing Sciences and Vice Chancellor for Academic Affairs and Dean of the Faculties, 111 Bryan Hall, Indiana University, Bloomington, IN 47405, USA. e-mail: [email protected]
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CHANGES IN CHILDREN’S VOICES Children seem to respond well to the idea of making pictures with their voices.2,3 Most children also seem to enjoy exploring a variety of vocal options. In traditional voice therapy, a voice model given by a clinician may sometimes be unsuitable because the clinician is not the same age as a child client and may also be a different gender from the client. Thus, if models are presented, clinicians often have to use recordings of children in order to present the most natural model. In addition to gender and age differences in the voices of clinicians and child clients, there are also differences in documented patterns of fundamental frequency variation. Prepubertal fundamental frequency variability was assumed to be similar between male and female children. However, Ferrand and Bloom4 studied intonation patterns in children and found that changes occur at ages 7 and 8, when males begin to use less variability than females do. Thus, with respect to intonation patterns, clinicians’ adult models may not be the most appropriate models for child clients. The use of cognitive cueing, which does not present a model but rather stimulates the child’s thought patterns, has the advantage of not constraining the response because the child is not trying to match someone else’s voice pattern. Thus, the present study was designed to see if cognitive cueing changes vocal variation in children. The purposes of the study were: 1. To compare children’s vocal patterns during reading with and without cognitive cues. 2. To determine if the semantic content of the sentence and the type of instruction influences the amount and type of vocal variability. 3. To determine if there are differences between male and female elementary school children in their vocal responses to cognitive cueing. Subjects Fifteen children, 9 males and 6 females, (ranging in age from 9.25 to 10.98 years), with a mean age of 10.13 years, served as subjects. Each of these children were native American English speakers and each had age-appropriate developmental skills as reported by their teachers. Each child had normal reading ability and was in overall good health. One subject was receiving speech-language pathology services for final position /r/ remediation and the oth-
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ers had no history of any type of speech or hearing disorder. MATERIALS AND METHODS Four sentences were chosen by the experimenters to cue rate and frequency changes (see Appendix 1). Sentence one was specifically designed to elicit an increase in duration by using the embedded slow motion cues implied in the words “slowly” and “dragging.” Sentence two specifically cued a decrease in duration by employing an increase in motion cue implied in the words “ran” and “fast” along with a short sentence length. Sentences three and four each cued an upward and downward movement in frequency by using upward or downward motion cues implied in the words “climbed” and “up” and “dived” and “down.” The subjects were given a printed sheet (the order of the sentences was randomized) and subjects were asked to read each of the sentences silently and then to speak it aloud. No cues were given to the children prior to the first aloud reading. This was the “no cue” trial condition. In the second trial, the children were asked to “think about” how they could use their voice to let the examiner “feel” the meaning of the text. Each child was then instructed to read the sentence aloud again. This was the cognitive cue trial. The experimenter did not provide models for the subjects. The cues were specifically designed to elicit changes in the duration and frequency of the readings of the sentences by using the embedded cues in the sentence and instructions provided by the experimenter (see Appendix). For each sentence, two spoken instructional cues were presented (see Appendix 1). These cues were selected to suggest specific images to the subjects. The subjects were recorded in a quiet elementary school speech therapy room by the first investigator. The recordings were made using a Sony PCM-1 (Sony Electronics, Park Ridge, NJ) digital audiotape (DAT) recorder using a head-mounted ATM75 electret condenser microphone (Audio-Technica, Stow, OH) placed at a distance of 3 inches from the subject’s mouth. Analysis The 15 subjects each read the four sentences two times, once during the “no cue” condition and once during the “cognitive cue” condition. Following the Journal of Voice, Vol. 16, No. 4, 2002
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recording sessions, all the sentences were analyzed using the CSpeech5 analysis software program to determine changes in duration and fundamental frequency. The material analyzed included a total of 120 sentences (15 subjects ⫻ 4 sentences ⫻ 2 conditions). Sentence duration, key word duration, phrase duration, overall sentence fundamental frequency variation, phrase fundamental frequency variation, and key word maximum fundamental frequency data were analyzed using the CSpeech program. Key words were selected for analysis in each of the sentences (see Appendix 1). Frequency contours for the overall sentence variability and maximum fundamental frequency for the key words were extracted using the short-term auto-correlation method. Fundamental frequency variability was determined by using the standard deviation of the overall sentence fundamental frequency. Frequency doubling and halving errors were manually edited by one of the experimenters before calculation. The measures were then subjected to a multivariate analysis of variance, with the independent variables including condition, sentence type, and gender. The dependent variables included overall fundamental frequency variation, key word maximum fundamental frequency, overall sentence duration, and key word duration. RESULTS Voice changes in response to the cognitive cues With respect to research question one, the results indicated that the subjects’ voices were more variable in the “cognitive cue” condition than in the “no cue” condition. Variability was determined by analyzing frequency variability in the sentence overall, the key phrases, and on the key words (sentence one, “slowly,” sentence two, “fast,” sentence three, “climbed,” and sentence four, “up”). In addition, variation was determined by analyzing duration changes in the sentence overall, the key phrases, and in the key words. Frequency variability was determined by using the fundamental frequency standard deviation (F0SD) of the targeted sentence, phrase, or key word. The frequency analyses were examined with respect to the expected outcome, that is, whether the target was a higher or lower frequency and whether the child showed a greater variability across the sentence, Journal of Voice, Vol. 16, No. 4, 2002
phrase, or targeted key word. Overall, when all the “cognitive cue” trials were compared to all the “no cue” trials, there was a significant main effect of condition on frequency variability (p = 0.008) and a significant main effect on maximum fundamental frequency on the key words (p = 0.020). The “cognitive cue” condition of the set of four sentences had a significant main effect on F0SD (p = 0.008). This indicated that when the children were asked to use their voices to produce the changes, they varied their voices markedly in comparison to the “no cue” condition. The changes were most significant in the sentences that were created to elicit a frequency change (sentences three and four) that included the embedded semantic cues for upward or downward movement. There were differences in the duration-targeted sentences also (sentences one and two), but these were not as great as in sentences three and four (see Figure 1). The maximum fundamental frequencies of the key words were analyzed to determine the effect of cueing on the key words of the sentences (sentence one, “slowly,” sentence two, “fast,” sentence three, “climbed,” and sentence four, “up”). There was an overall significant main effect of condition on the maximum fundamental frequencies of the key words across sentences (p = 0.020), the effects of which are most evident in sentence four (see Figure 2). The maximum F0 on the word “up” was greatly increased in the “cognitive cue” condition versus the “no cue” condition. The key word in sentence three, “climbed,” had the lowest key word frequency variability change from the “no cue” to “cognitive cue” condition. Sentence three was more variable overall when the children were cued, but the key word “climbed” was not significantly different between the “no cue” and “cognitive cue” version. In sentence three, there was a significant effect of condition on phrase one (sentence one, “The boy walked slowly to school . . . ”; sentence two, not applicable; sentence three, “The plane climbed high in the sky . . . ”; sentence four, “She pulled the zipper up . . . ”) maximum F0 (p = 0.036). Sentence four, as would be expected with the embedded action cues for upward movement (i.e., “pulled” and “up”), had the highest variability in both the “cognitive cue” and “no cue” conditions. Phrase data for sentence two was not analyzed because of the short sentence length.
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Interaction of semantic cues and instructions It was hypothesized that the children would vary their voices in response to the embedded semantic cues and the instructions given by the experimenter. Thus, in sentence one, the embedded semantic cue of “slowly” in addition to the instructions, was aimed at eliciting reduced rate and an increase in overall sentence duration. Sentence two used the embedded cue of “fast” along with the instruction aimed at eliciting increased rate and a decrease in overall sentence duration. Changes in duration were determined by obtaining difference scores between the “no cue” and “cognitive cue” conditions. These were analyzed in relation to whether the expected outcome was an increase in rate or a decrease in duration and vice versa. There was not a significant main effect of condition on duration changes during the readings in the “cognitive cue” condition (Figure 3). However, there were significant interaction effects that are discussed in Results pertaining to research question two. To answer research question two, we considered the effect of instructions and the semantic content during the “cognitive cue” condition. It is important to remember that the instructions were parameter specific. They either directed the child’s attention to
an action or a feeling and a possible change in either frequency or duration. Words such as “fast” and “slowly” were used to suggest durational changes and words such as “climbed” and “up” were used to suggest frequency changes. It seemed as if the instructions exerted a significant effect on changes noted on the specific parameters targeted. Because of their semantic content, we further analyzed key phrases in the sentences in order to look at the specific effect of words in the sentences that were likely to elicit images in a child’s mind. These phrases, along with the key words were chosen to compare voice changes with respect to frequency and duration differences between the “no cue” and “cognitive cue” condition trials. There was a significant interaction of condition and sentence type on the maximum F0 of the key word (p < 0.001). When the children were presented with sentences containing the embedded cues of movement or direction along with an instruction to use their voices to signal movement, these children, as a group, varied their voices by emphasizing key words by increasing frequency variation. In addition, there was a significant main effect of sentence type on the maximum F0 of the key words
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CHANGES IN CHILDREN’S VOICES (p < 0.001) and on F0SD (p = 0.050). Sentence one, or the slowed rate-targeted sentence, had a decrease in maximum F0 of the key word “slowly” in the “cognitive cue” condition while sentence two, the increased rate-targeted sentence, had an increase in maximum F0 of the key word “fast.” Results also showed a significant main effect of sentence type on duration (p < 0.001). The rate change sentences showed the greatest overall sentence duration differences, as would be expected. In sentence one, the sentence had embedded images of increased or decreased length (i.e., “slowly,” “dragging”) utilizing semantic imagery of slowed movement. Sentence two had an embedded image of decreased duration as well as a shorter overall sentence length. Sentence duration results indicated that the subjects varied the duration of their utterances in accordance with the semantic images. This is in marked contrast to sentences three and four, which did not elicit a significant increase or decrease in duration as neither sentence had embedded durational images. There was also a significant interaction of sentence and condition (p = 0.009). When the subjects were given specific instructions in addition to the embedded images, the overall duration was affected. For instance, in sentence two, the increased rate sentence, the subjects as a group actually decreased the duration of the sentence by apparently responding to the embedded cue of “fast” along with the short overall sentence length. In sentence one, the words “slowly” and “dragging” appeared with the experimenter’s instructions to suggest the slow movement of the child walking to school. The results also showed a significant interaction between type of sentence and condition on key word duration (p = 0.028). In the sentences that targeted slowing of rate as the appropriate change, the children’s responses were analyzed and demonstrated increased sentence duration and increased key word duration. The key words were then analyzed in order to assess whether the variation was due to an overall increase in sentence duration or to increased key word duration. When the children were cued for the duration-targeted sentences, appropriate duration changes resulted. Results showed a significant main effect of sentence type on the duration of the key
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word (p < 0.001). This was most evident in sentence one, where the duration of “slowly” was increased significantly from the “no cue” to the “cognitive cue” trial. In sentence two, the duration of the word “fast” was also increased, indicating change; however, the variation was not as great as it was in sentence one. This would be expected, as the embedded cues were for increased rate. However, the children still increased duration on the key word “fast” while increasing the overall sentence duration. Sentences three and four, which did not target duration changes, did not elicit significant differences in key word duration (Figure 4). As one would expect and as earlier studies have suggested, vocal variation is dynamic. When voice changes occur as a result of changes in thought patterns, there is the possibility of variation in all parameters. We looked at the measurable changes in duration that occurred during the cued readings when the instructions targeted only frequency. This was accomplished by conducting a bivariate correlational analysis on the data in the “cognitive cue” condition for each sentence. There were not any significant differences across subjects in relation to durational effects when the sentences and instructions specifically targeted frequency changes. However, in sentence one, or the decreased rate-targeted sentence, there was a correlation between the maximum fundamental frequency for the key word “slowly” and the duration (r = 0.542), indicating that the children may have been emphasizing the movement by manipulating both frequency and duration on “slowly.” In sentence two, the increased rate-targeted sentence, there were also significant changes in frequency when duration was targeted. In sentence three, a frequencytargeted sentence, there was a negative correlation between overall sentence F0SD and the maximum fundamental frequency on the key word “climbed” (r = -0.728). There were no significant effects or interactions between duration and frequency in sentence four. Gender Differences Results showed a significant interaction of condition, sentence type, and gender (p = 0.034) (Figures 5 and 6). The male subjects had much less frequency variability overall in the reading tasks than did the feJournal of Voice, Vol. 16, No. 4, 2002
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male subjects in the “no cue” condition (see Figure 7). The males also showed a greater increase in frequency variability across sentences than the females did in the “cognitive cue” condition. The female subjects showed an increase also, but this increase was not as great as in the male speakers. Overall, the female speakers demonstrated more frequency variability than did the males when all trials were analyzed together. The effects of sentence type and condition by gender were also statistically significant (p = 0.04). Overall, the males increased F0SD on each of the four sentences, with the greatest increase seen on sentences three and four, which focused on frequency. The female speakers showed an increase in frequency variability in three of the four sentences. The female speakers showed less frequency variability on sentence two, which was the decreased duration sentence, in the “cognitive cue” condition. However, though it was reduced, the female subjects still had greater frequency variability than did the males on sentence two. The results demonstrated that the children participating in this study changed their vocal patterns in respect to the cognitive cues. Changes
were noted in both the frequency and duration parameters for both males and females. However, since the males did not have much variability in the “no cue” condition, the difference between the “no cue” and “cognitive cue” condition variability was more striking for the males than for the females (Figure 7). DISCUSSION All 15 subjects varied their voices in response to the cognitive cues that were presented to stimulate duration and frequency changes in their readings. The effects of cognitive cueing on fundamental frequency variation were noted in each of the four sentence types. This result was expected based on the previous work of Andrews, Shrivastav, and Yamaguchi,1 which reported that adults with voice disorders increased vocal variation when they were given cognitive cues. However, the normal speakers used in that study were trained singers, and produced significant frequency variability in each condition. The subjects in the present study had no history of formal singing training or voice disorders. In this study the semantically embedded cues in rate-targeted sentences three and four, as well as the overt instructions Journal of Voice, Vol. 16, No. 4, 2002
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given by the experimenter, elicited a significant increase in fundamental frequency variability. The frequency-targeted sentences elicited more variation in the subjects’ voices than did the rate-targeted sentences, as would be expected. There was also an increase in frequency variation in the slow rate-targeted duration sentence, but not in the increased duration sentence. The subjects all increased overall sentence duration in sentence one (the duration-targeted sentence). This was consistent with the data previously obtained for adults.1 However, the child subjects in this study did not have significant increases in overall sentence duration in sentences two, three, or four. This is in contrast to the previous findings that adult speakers increased utterance duration when an additional cognitive demand was placed on the speaker. In addition, the key word duration for “slowly” in sentence one was increased in the “cognitive cue” condition. This difference was significantly unlike the increase of the length of the key word “fast” in the “cognitive cue” condition in sentence two. The subjects decreased the duration of sentence two overall, while not making significant changes in duration on the key word “fast.” Journal of Voice, Vol. 16, No. 4, 2002
An interesting interaction was noted between frequency and duration changes in sentence one. In this rate-targeted sentence, the significant correlation between the maximum fundamental frequency of the key word “slowly” and the duration of the sentence indicated that frequency changes might also have been necessary to produce the appropriate imagery of slowed movement. However, when duration was targeted, the subjects decreased their frequency when there was a cue to reduce rate. The interaction of frequency and duration was not noted in sentences two, three, or four. The interaction of frequency and duration in sentence one may indicate that when the children were cued for a slowed rate change, they also included a frequency change. The overall frequency variability of sentence one, a rate-targeted sentence, was increased during the subjects’ cued readings (Figure 8). Frequency variability was accomplished by decreasing frequency throughout the sentence. There were decreases in frequency on the key word “slowly,” the phrase “the boy walked slowly to school,” and on the mean fundamental frequency of the sentence. This indicated that the subjects varied their voices when reading this
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sentence by decreasing frequency. The decreased frequency in the “cognitive cue” condition may have resulted from the subjects using their voices to suggest slowed motion by changing their frequency. There was a lowering of frequency at the end of sentence one, as would be expected with natural “end of sentence” intonation contours. However, there was a greater decrease in frequency during the “cognitive cue” condition, indicating that the children not only decreased their frequency on “slowly,” but that the effect was also present on “dragging,” and was not only related to “end of sentence” imperatives. The subjects also increased their frequency variability on the rate-targeted sentence two, where there were embedded cues for “fast” movement. The subjects increased their frequency variability by increasing their mean fundamental frequency on the key word “fast” and across the sentence. When results were compared with sentence one, where rate was targeted to be slowed, it was seen that the subjects changed both their rate and frequency in the “cognitive cue” condition. Thus, when the children were producing a fast rate, they also increased their frequency.
The frequency-targeted sentence “the plane climbed high in the sky, then dived down” apparently did not provide as salient a cue for stimulation of frequency change as did the sentence “she pulled the zipper up, then down.” The referents in sentences three and four were “climbed” and “up.” Children ages 9 and 10 may not have had the life experiences to imagine “climbed” as it related to an airplane increasing in altitude, while the children certainly could identify with pulling zippers on jackets up and down. This example reinforces the notion that selection of materials affects the responses. In order to examine the effects of specific words on the extent of the voice changes, an additional analysis was conducted to compare the upward voice movement on “climbed” versus “climbed high.” The referent “high” appeared to be necessary to initiate a frequency change as can be seen by inspection of Figures 9, 10, and 11. The subjects did not change their vocal production on the key word “climbed,” while it is clear by inspecting the figures that the majority of the subjects responded to the “cognitive cue” condition by changing their voices on the phrase that included “climbed high.” Journal of Voice, Vol. 16, No. 4, 2002
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Subject FIGURE 11. Difference in fundamental frequency variability (F0SD) on the key word “climbed” in sentence 3.
The subjects also changed their voices in sentence four where overall sentence frequency variability was increased. The increase in variability in this sentence seemed to be primarily due to the effects of the key word “up.” Frequency variability on the key word, on the phrase that included the key word, and on the maximum fundamental frequency used in both the key word and phrase, indicated that the subjects found the movement of a zipper “up” to be a salient cue for voice change. Voice variation on the second phrase, “then down” was not as marked in the “cognitive cue” condition as it was on the first phrase. Movement of a zipper down indicates movement of the zipper back to its original position, perhaps not indicating a downward movement as much as a return to the neutral position of the zipper. Gender differences Gender differences were present and compare well to the data reported in Ferrand and Bloom.4 Results from that study indicated that prepubertal voice differences between males and females begin after ages 7 or 8. The results of the present study indicated that
9 and 10-year-old males and females do differ in frequency variability during reading. However, the Ferrand and Bloom4 data was elicited through spontaneous speech sampling while the tasks in this study utilized written text. Males in the present study had less F0SD than females in both the “no cue” and “cognitive cue” conditions but showed an increase in variability from the “no cue” condition to the “cognitive cue” condition. The “cognitive cue” effects in this study may be due to the relative lack of frequency variability seen in the “no cue” readings. Possible reasons for reduced variability could be due to the subjects’ relative unfamiliarity with the stimulus sentences that not only improved with subsequent readings, but also improved when given the appropriate cognitive cues. However, it does seem that once the children’s imaginations were stimulated and an appropriate instruction was given (suggesting that voice reflect the imagery in the words), the subjects’ variability improved markedly. The subjects did respond to specific cues for frequency and durational changes, but changes in both parameters were evident even when Journal of Voice, Vol. 16, No. 4, 2002
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they were not specifically cued. This suggests the notion that when the imagination is stimulated, the voice reflects natural movement in all parameters. It may also be that some generalization occurs from trial to trial. As is the case with interventions in other areas of speech-language pathology, individual differences were noted. For instance, in sentence one, one subject had consistent difficulty with variation of frequency across the sentence, phrase, and key word. This subject did not respond differently between the “no cue” and “cognitive cue” conditions. With respect to the effect of the specific parameter targeted, there were individual subjects throughout the study who did not respond to any “cognitive cue” conditions. For example, in sentence four, one subject consistently did not respond to cognitive cues for movement. Each of the remaining subjects varied their voices markedly as can be seen from analysis of maximum fundamental frequency and frequency variability measures. When investigating the effect of generalization in the field of phonology, Elbert et al6 found that children often learn more than the target that is taught. It is interesting to note that children demonstrate great variation in their generalization patterns.6 The technique of cognitive cueing provides a way of eliciting natural patterns of voice variability that clinicians cannot model for individual children. Cognitive cueing seems to allow children the freedom to let their voices reflect what the semantic images mean to them. Gierut, Elbert, and Dinnsen,7 have discussed the importance of considering the starting point in phonological treatment with children. They found that children, who were least knowledgeable at the onset of their training, might generalize more dramatically across the sound system. Males in the present study, less naturally variable, became more variable after cueing. Similarly, perhaps the technique of cognitive cueing might be especially helpful for children with specific disorders related to variation of frequency, timing, and intensity such as those seen in the hearing-impaired and developmentally disabled populations. CONCLUSIONS As earlier cognitive cueing studies have indicated, semantic content and imagery may be used to elicit vocal variability. The semantic cues, or the cues embedded in the text, can be highlighted by instructions Journal of Voice, Vol. 16, No. 4, 2002
asking children to imagine what is happening (e.g., actions) or what they are feeling. The cues in this study were limited to the parameters of timing and frequency and both the female and male children responded well to them. Overall, it has been shown that children’s voices do change duration and frequency characteristics when instructions to stimulate their thinking are provided. Furthermore, these children’s voices changed significantly in the direction indicated by both the semantics inherent in the words and in the parameter-specific instructions. This occurred in three of the four sentences. It appears that those sentences and the instructions given were meaningful to this group of school-aged children. One major finding of this study is that the children’s voices were generally more variable when they were cued. Not only were the targeted parameters varied, but other parameters as well. Although there were no significant differences between the frequency levels of “climbed” alone in the “no cue” and “cognitive cue” conditions, there were differences between “climbed high” renditions of the phrase between the trials. This finding reminds us that clinicians must take care to look for changes on more than one word. Future studies will investigate further the interaction of semantically embedded cues and experimenter instructions, the effects of cognitive cueing on children with voice disorders, and the effects of cognitive cueing in eliciting vocal change in the spontaneous speech of school-aged children. REFERENCES 1. Andrews ML, Shrivastav R, Yamaguchi H. The role of cognitive cueing in eliciting vocal variability. J Voice. 2000;14: 494-501. 2. Andrews ML. Voice Treatment in Children and Adolescents. San Diego, Calif: Singular—Thomson Learning; 2001. 3. Andrews ML. Voice Therapy for Children: The Elementary School Years. San Diego, Calif: Singular Publishing Group; 1991. 4. Ferrand CT, Bloom RL. Gender differences in children’s intonational patterns. J Voice. 1996;10;284-291. 5. Milenkovic PH. CspeechSP [computer software]. Madison, WI: University of Wisconsin—Madison: 1997. 6. Elbert M, Dinnsen DA, Swartzlander P, Chin S. Generalization to conversational speech. J Speech Hear Disord. 1990; 55:694-699. 7. Gierut JA, Elbert M, Dinnsen D. A functional analysis of phonological knowledge and generalization learning in misarticulating children. J Speech Hear Res. 1987;30:462-479.
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APPENDIX 1 The subjects were instructed to read each of these sentences silently to themselves, followed by the cognitive cues. 1. The boy walked slowly to school, dragging his feet. Cues: a. “Did you feel how he was walking slowly and dragging his feet? I think that you can make me feel that he was walking slowly even more.” b. “Think about walking slowly and dragging your feet. Think about how you could use your voice to make me feel how he is walking. Use your voice to let me feel the boy walking slowly.” Key word: slowly 2. He ran as fast as he could. Cues: a. “Did you feel how he was running fast? I think that you can make me feel that he was running fast even more.” b. “Think about the boy running as fast as he could. Think about how you could use your voice to make me feel how fast he is running. Use your voice to let me feel the boy running fast.” Key word: fast 3. The plane climbed high in the sky, then dived down. Cues: a. “Did you feel how the plane was climbing and diving? I think that you can make me feel the plane ride even more.” b. “Think about flying up and then down. Think about how you could use your voice to make me feel that feeling. Use your voice to let me feel the plane ride.” Key word: climbed 4. She pulled the zipper up, then down. Cues: a. “Did you feel how the zipper was moving up and down? I think that you can make me feel that she was zipping up and down even more.” a. “Think about zipping your jacket. Think about how you could use your voice to make me feel how the zipper moves. Use your voice to let me feel the zipper moving.” Key word: up
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Changes in Children’s Voices: The Effect of Cognitive Cues *Todd A. Bohnenkamp, *Moya Andrews, *Rahul Shrivastav, and †Anne Summers *Indiana University, Bloomington, Indiana; †Monroe County Community School Corporation, Bloomington, Indiana
Summary: Variation in duration and frequency during two readings of each of four sentences by 15 normal 9- and 10-year-old children were compared. Instructions to the children included overt cues designed specifically to elicit durational and frequency changes. Children demonstrated increased sentence variability in their voices when they were cued. Specific key words in the four sentences were also analyzed and results indicated that semantic content in addition to parameter-specific cognitive cues provided a significant effect. The male 9 and 10-year-old subjects showed less variability in “no cue” readings than the females, but showed a greater increase in voice change during the “cognitive cue” readings. Implications for theory and practice are discussed. Key Words: Cognitive cueing—Voice therapy—Voice therapy in children.
INTRODUCTION
that are suggested by the written words of a text and also on the speakers’ thoughts and feelings regarding the text. Cues and images of this type have traditionally been used by drama and singing teachers to elicit vocal behaviors, but the use of this technique with children has not been subjected to empirical scrutiny. Previous research has indicated that cognitive cueing is aided by the semantic imagery inherent in the material presented. When a subject is to read from a text, words such as action words (e.g., jump), spatial words (e.g., up and down), and emotive words (e.g., happy, sad) can easily be identified as “picture words.” The experimenter can then provide cues that stimulate thinking about such word pictures. For example, a sentence used in a previous research study: “The submarine sank to the bottom of the sea” was used with the cue “think about the surface of the water; start your voice there and show me how the submarine goes down.”1 This sentence included the embedded semantic cues of downward motion and was presented with specific instructions to speakers to indicate a downward movement of the voice.
Cognitive cueing is an approach to voice treatment that stimulates thought patterns as a way of changing speakers’ voices. Previous studies of cognitive cueing have indicated that this is a promising technique for voice therapy in adults with and without voice disorders.1 In studies of adults, the documented changes in vocal behavior with cognitive cues included an increase in fundamental frequency variation, increased intensity variation, and increased sentence duration.1 Cognitive cueing focuses the attention of the speaker on the actions and images Accepted for publication April 16, 2002. This paper was presented at the 30th Annual Voice Foundation Symposium: Care of the Professional Voice, June 13–17, 2001, Philadelphia, Pennsylvania. Address correspondence and reprint requests to Address correspondence and reprint requests to Moya Andrews, Professor of Speech and Hearing Sciences and Vice Chancellor for Academic Affairs and Dean of the Faculties, 111 Bryan Hall, Indiana University, Bloomington, IN 47405, USA. e-mail: [email protected]
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CHANGES IN CHILDREN’S VOICES Children seem to respond well to the idea of making pictures with their voices.2,3 Most children also seem to enjoy exploring a variety of vocal options. In traditional voice therapy, a voice model given by a clinician may sometimes be unsuitable because the clinician is not the same age as a child client and may also be a different gender from the client. Thus, if models are presented, clinicians often have to use recordings of children in order to present the most natural model. In addition to gender and age differences in the voices of clinicians and child clients, there are also differences in documented patterns of fundamental frequency variation. Prepubertal fundamental frequency variability was assumed to be similar between male and female children. However, Ferrand and Bloom4 studied intonation patterns in children and found that changes occur at ages 7 and 8, when males begin to use less variability than females do. Thus, with respect to intonation patterns, clinicians’ adult models may not be the most appropriate models for child clients. The use of cognitive cueing, which does not present a model but rather stimulates the child’s thought patterns, has the advantage of not constraining the response because the child is not trying to match someone else’s voice pattern. Thus, the present study was designed to see if cognitive cueing changes vocal variation in children. The purposes of the study were: 1. To compare children’s vocal patterns during reading with and without cognitive cues. 2. To determine if the semantic content of the sentence and the type of instruction influences the amount and type of vocal variability. 3. To determine if there are differences between male and female elementary school children in their vocal responses to cognitive cueing. Subjects Fifteen children, 9 males and 6 females, (ranging in age from 9.25 to 10.98 years), with a mean age of 10.13 years, served as subjects. Each of these children were native American English speakers and each had age-appropriate developmental skills as reported by their teachers. Each child had normal reading ability and was in overall good health. One subject was receiving speech-language pathology services for final position /r/ remediation and the oth-
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ers had no history of any type of speech or hearing disorder. MATERIALS AND METHODS Four sentences were chosen by the experimenters to cue rate and frequency changes (see Appendix 1). Sentence one was specifically designed to elicit an increase in duration by using the embedded slow motion cues implied in the words “slowly” and “dragging.” Sentence two specifically cued a decrease in duration by employing an increase in motion cue implied in the words “ran” and “fast” along with a short sentence length. Sentences three and four each cued an upward and downward movement in frequency by using upward or downward motion cues implied in the words “climbed” and “up” and “dived” and “down.” The subjects were given a printed sheet (the order of the sentences was randomized) and subjects were asked to read each of the sentences silently and then to speak it aloud. No cues were given to the children prior to the first aloud reading. This was the “no cue” trial condition. In the second trial, the children were asked to “think about” how they could use their voice to let the examiner “feel” the meaning of the text. Each child was then instructed to read the sentence aloud again. This was the cognitive cue trial. The experimenter did not provide models for the subjects. The cues were specifically designed to elicit changes in the duration and frequency of the readings of the sentences by using the embedded cues in the sentence and instructions provided by the experimenter (see Appendix). For each sentence, two spoken instructional cues were presented (see Appendix 1). These cues were selected to suggest specific images to the subjects. The subjects were recorded in a quiet elementary school speech therapy room by the first investigator. The recordings were made using a Sony PCM-1 (Sony Electronics, Park Ridge, NJ) digital audiotape (DAT) recorder using a head-mounted ATM75 electret condenser microphone (Audio-Technica, Stow, OH) placed at a distance of 3 inches from the subject’s mouth. Analysis The 15 subjects each read the four sentences two times, once during the “no cue” condition and once during the “cognitive cue” condition. Following the Journal of Voice, Vol. 16, No. 4, 2002
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recording sessions, all the sentences were analyzed using the CSpeech5 analysis software program to determine changes in duration and fundamental frequency. The material analyzed included a total of 120 sentences (15 subjects ⫻ 4 sentences ⫻ 2 conditions). Sentence duration, key word duration, phrase duration, overall sentence fundamental frequency variation, phrase fundamental frequency variation, and key word maximum fundamental frequency data were analyzed using the CSpeech program. Key words were selected for analysis in each of the sentences (see Appendix 1). Frequency contours for the overall sentence variability and maximum fundamental frequency for the key words were extracted using the short-term auto-correlation method. Fundamental frequency variability was determined by using the standard deviation of the overall sentence fundamental frequency. Frequency doubling and halving errors were manually edited by one of the experimenters before calculation. The measures were then subjected to a multivariate analysis of variance, with the independent variables including condition, sentence type, and gender. The dependent variables included overall fundamental frequency variation, key word maximum fundamental frequency, overall sentence duration, and key word duration. RESULTS Voice changes in response to the cognitive cues With respect to research question one, the results indicated that the subjects’ voices were more variable in the “cognitive cue” condition than in the “no cue” condition. Variability was determined by analyzing frequency variability in the sentence overall, the key phrases, and on the key words (sentence one, “slowly,” sentence two, “fast,” sentence three, “climbed,” and sentence four, “up”). In addition, variation was determined by analyzing duration changes in the sentence overall, the key phrases, and in the key words. Frequency variability was determined by using the fundamental frequency standard deviation (F0SD) of the targeted sentence, phrase, or key word. The frequency analyses were examined with respect to the expected outcome, that is, whether the target was a higher or lower frequency and whether the child showed a greater variability across the sentence, Journal of Voice, Vol. 16, No. 4, 2002
phrase, or targeted key word. Overall, when all the “cognitive cue” trials were compared to all the “no cue” trials, there was a significant main effect of condition on frequency variability (p = 0.008) and a significant main effect on maximum fundamental frequency on the key words (p = 0.020). The “cognitive cue” condition of the set of four sentences had a significant main effect on F0SD (p = 0.008). This indicated that when the children were asked to use their voices to produce the changes, they varied their voices markedly in comparison to the “no cue” condition. The changes were most significant in the sentences that were created to elicit a frequency change (sentences three and four) that included the embedded semantic cues for upward or downward movement. There were differences in the duration-targeted sentences also (sentences one and two), but these were not as great as in sentences three and four (see Figure 1). The maximum fundamental frequencies of the key words were analyzed to determine the effect of cueing on the key words of the sentences (sentence one, “slowly,” sentence two, “fast,” sentence three, “climbed,” and sentence four, “up”). There was an overall significant main effect of condition on the maximum fundamental frequencies of the key words across sentences (p = 0.020), the effects of which are most evident in sentence four (see Figure 2). The maximum F0 on the word “up” was greatly increased in the “cognitive cue” condition versus the “no cue” condition. The key word in sentence three, “climbed,” had the lowest key word frequency variability change from the “no cue” to “cognitive cue” condition. Sentence three was more variable overall when the children were cued, but the key word “climbed” was not significantly different between the “no cue” and “cognitive cue” version. In sentence three, there was a significant effect of condition on phrase one (sentence one, “The boy walked slowly to school . . . ”; sentence two, not applicable; sentence three, “The plane climbed high in the sky . . . ”; sentence four, “She pulled the zipper up . . . ”) maximum F0 (p = 0.036). Sentence four, as would be expected with the embedded action cues for upward movement (i.e., “pulled” and “up”), had the highest variability in both the “cognitive cue” and “no cue” conditions. Phrase data for sentence two was not analyzed because of the short sentence length.
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Interaction of semantic cues and instructions It was hypothesized that the children would vary their voices in response to the embedded semantic cues and the instructions given by the experimenter. Thus, in sentence one, the embedded semantic cue of “slowly” in addition to the instructions, was aimed at eliciting reduced rate and an increase in overall sentence duration. Sentence two used the embedded cue of “fast” along with the instruction aimed at eliciting increased rate and a decrease in overall sentence duration. Changes in duration were determined by obtaining difference scores between the “no cue” and “cognitive cue” conditions. These were analyzed in relation to whether the expected outcome was an increase in rate or a decrease in duration and vice versa. There was not a significant main effect of condition on duration changes during the readings in the “cognitive cue” condition (Figure 3). However, there were significant interaction effects that are discussed in Results pertaining to research question two. To answer research question two, we considered the effect of instructions and the semantic content during the “cognitive cue” condition. It is important to remember that the instructions were parameter specific. They either directed the child’s attention to
an action or a feeling and a possible change in either frequency or duration. Words such as “fast” and “slowly” were used to suggest durational changes and words such as “climbed” and “up” were used to suggest frequency changes. It seemed as if the instructions exerted a significant effect on changes noted on the specific parameters targeted. Because of their semantic content, we further analyzed key phrases in the sentences in order to look at the specific effect of words in the sentences that were likely to elicit images in a child’s mind. These phrases, along with the key words were chosen to compare voice changes with respect to frequency and duration differences between the “no cue” and “cognitive cue” condition trials. There was a significant interaction of condition and sentence type on the maximum F0 of the key word (p < 0.001). When the children were presented with sentences containing the embedded cues of movement or direction along with an instruction to use their voices to signal movement, these children, as a group, varied their voices by emphasizing key words by increasing frequency variation. In addition, there was a significant main effect of sentence type on the maximum F0 of the key words
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CHANGES IN CHILDREN’S VOICES (p < 0.001) and on F0SD (p = 0.050). Sentence one, or the slowed rate-targeted sentence, had a decrease in maximum F0 of the key word “slowly” in the “cognitive cue” condition while sentence two, the increased rate-targeted sentence, had an increase in maximum F0 of the key word “fast.” Results also showed a significant main effect of sentence type on duration (p < 0.001). The rate change sentences showed the greatest overall sentence duration differences, as would be expected. In sentence one, the sentence had embedded images of increased or decreased length (i.e., “slowly,” “dragging”) utilizing semantic imagery of slowed movement. Sentence two had an embedded image of decreased duration as well as a shorter overall sentence length. Sentence duration results indicated that the subjects varied the duration of their utterances in accordance with the semantic images. This is in marked contrast to sentences three and four, which did not elicit a significant increase or decrease in duration as neither sentence had embedded durational images. There was also a significant interaction of sentence and condition (p = 0.009). When the subjects were given specific instructions in addition to the embedded images, the overall duration was affected. For instance, in sentence two, the increased rate sentence, the subjects as a group actually decreased the duration of the sentence by apparently responding to the embedded cue of “fast” along with the short overall sentence length. In sentence one, the words “slowly” and “dragging” appeared with the experimenter’s instructions to suggest the slow movement of the child walking to school. The results also showed a significant interaction between type of sentence and condition on key word duration (p = 0.028). In the sentences that targeted slowing of rate as the appropriate change, the children’s responses were analyzed and demonstrated increased sentence duration and increased key word duration. The key words were then analyzed in order to assess whether the variation was due to an overall increase in sentence duration or to increased key word duration. When the children were cued for the duration-targeted sentences, appropriate duration changes resulted. Results showed a significant main effect of sentence type on the duration of the key
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word (p < 0.001). This was most evident in sentence one, where the duration of “slowly” was increased significantly from the “no cue” to the “cognitive cue” trial. In sentence two, the duration of the word “fast” was also increased, indicating change; however, the variation was not as great as it was in sentence one. This would be expected, as the embedded cues were for increased rate. However, the children still increased duration on the key word “fast” while increasing the overall sentence duration. Sentences three and four, which did not target duration changes, did not elicit significant differences in key word duration (Figure 4). As one would expect and as earlier studies have suggested, vocal variation is dynamic. When voice changes occur as a result of changes in thought patterns, there is the possibility of variation in all parameters. We looked at the measurable changes in duration that occurred during the cued readings when the instructions targeted only frequency. This was accomplished by conducting a bivariate correlational analysis on the data in the “cognitive cue” condition for each sentence. There were not any significant differences across subjects in relation to durational effects when the sentences and instructions specifically targeted frequency changes. However, in sentence one, or the decreased rate-targeted sentence, there was a correlation between the maximum fundamental frequency for the key word “slowly” and the duration (r = 0.542), indicating that the children may have been emphasizing the movement by manipulating both frequency and duration on “slowly.” In sentence two, the increased rate-targeted sentence, there were also significant changes in frequency when duration was targeted. In sentence three, a frequencytargeted sentence, there was a negative correlation between overall sentence F0SD and the maximum fundamental frequency on the key word “climbed” (r = -0.728). There were no significant effects or interactions between duration and frequency in sentence four. Gender Differences Results showed a significant interaction of condition, sentence type, and gender (p = 0.034) (Figures 5 and 6). The male subjects had much less frequency variability overall in the reading tasks than did the feJournal of Voice, Vol. 16, No. 4, 2002
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male subjects in the “no cue” condition (see Figure 7). The males also showed a greater increase in frequency variability across sentences than the females did in the “cognitive cue” condition. The female subjects showed an increase also, but this increase was not as great as in the male speakers. Overall, the female speakers demonstrated more frequency variability than did the males when all trials were analyzed together. The effects of sentence type and condition by gender were also statistically significant (p = 0.04). Overall, the males increased F0SD on each of the four sentences, with the greatest increase seen on sentences three and four, which focused on frequency. The female speakers showed an increase in frequency variability in three of the four sentences. The female speakers showed less frequency variability on sentence two, which was the decreased duration sentence, in the “cognitive cue” condition. However, though it was reduced, the female subjects still had greater frequency variability than did the males on sentence two. The results demonstrated that the children participating in this study changed their vocal patterns in respect to the cognitive cues. Changes
were noted in both the frequency and duration parameters for both males and females. However, since the males did not have much variability in the “no cue” condition, the difference between the “no cue” and “cognitive cue” condition variability was more striking for the males than for the females (Figure 7). DISCUSSION All 15 subjects varied their voices in response to the cognitive cues that were presented to stimulate duration and frequency changes in their readings. The effects of cognitive cueing on fundamental frequency variation were noted in each of the four sentence types. This result was expected based on the previous work of Andrews, Shrivastav, and Yamaguchi,1 which reported that adults with voice disorders increased vocal variation when they were given cognitive cues. However, the normal speakers used in that study were trained singers, and produced significant frequency variability in each condition. The subjects in the present study had no history of formal singing training or voice disorders. In this study the semantically embedded cues in rate-targeted sentences three and four, as well as the overt instructions Journal of Voice, Vol. 16, No. 4, 2002
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given by the experimenter, elicited a significant increase in fundamental frequency variability. The frequency-targeted sentences elicited more variation in the subjects’ voices than did the rate-targeted sentences, as would be expected. There was also an increase in frequency variation in the slow rate-targeted duration sentence, but not in the increased duration sentence. The subjects all increased overall sentence duration in sentence one (the duration-targeted sentence). This was consistent with the data previously obtained for adults.1 However, the child subjects in this study did not have significant increases in overall sentence duration in sentences two, three, or four. This is in contrast to the previous findings that adult speakers increased utterance duration when an additional cognitive demand was placed on the speaker. In addition, the key word duration for “slowly” in sentence one was increased in the “cognitive cue” condition. This difference was significantly unlike the increase of the length of the key word “fast” in the “cognitive cue” condition in sentence two. The subjects decreased the duration of sentence two overall, while not making significant changes in duration on the key word “fast.” Journal of Voice, Vol. 16, No. 4, 2002
An interesting interaction was noted between frequency and duration changes in sentence one. In this rate-targeted sentence, the significant correlation between the maximum fundamental frequency of the key word “slowly” and the duration of the sentence indicated that frequency changes might also have been necessary to produce the appropriate imagery of slowed movement. However, when duration was targeted, the subjects decreased their frequency when there was a cue to reduce rate. The interaction of frequency and duration was not noted in sentences two, three, or four. The interaction of frequency and duration in sentence one may indicate that when the children were cued for a slowed rate change, they also included a frequency change. The overall frequency variability of sentence one, a rate-targeted sentence, was increased during the subjects’ cued readings (Figure 8). Frequency variability was accomplished by decreasing frequency throughout the sentence. There were decreases in frequency on the key word “slowly,” the phrase “the boy walked slowly to school,” and on the mean fundamental frequency of the sentence. This indicated that the subjects varied their voices when reading this
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sentence by decreasing frequency. The decreased frequency in the “cognitive cue” condition may have resulted from the subjects using their voices to suggest slowed motion by changing their frequency. There was a lowering of frequency at the end of sentence one, as would be expected with natural “end of sentence” intonation contours. However, there was a greater decrease in frequency during the “cognitive cue” condition, indicating that the children not only decreased their frequency on “slowly,” but that the effect was also present on “dragging,” and was not only related to “end of sentence” imperatives. The subjects also increased their frequency variability on the rate-targeted sentence two, where there were embedded cues for “fast” movement. The subjects increased their frequency variability by increasing their mean fundamental frequency on the key word “fast” and across the sentence. When results were compared with sentence one, where rate was targeted to be slowed, it was seen that the subjects changed both their rate and frequency in the “cognitive cue” condition. Thus, when the children were producing a fast rate, they also increased their frequency.
The frequency-targeted sentence “the plane climbed high in the sky, then dived down” apparently did not provide as salient a cue for stimulation of frequency change as did the sentence “she pulled the zipper up, then down.” The referents in sentences three and four were “climbed” and “up.” Children ages 9 and 10 may not have had the life experiences to imagine “climbed” as it related to an airplane increasing in altitude, while the children certainly could identify with pulling zippers on jackets up and down. This example reinforces the notion that selection of materials affects the responses. In order to examine the effects of specific words on the extent of the voice changes, an additional analysis was conducted to compare the upward voice movement on “climbed” versus “climbed high.” The referent “high” appeared to be necessary to initiate a frequency change as can be seen by inspection of Figures 9, 10, and 11. The subjects did not change their vocal production on the key word “climbed,” while it is clear by inspecting the figures that the majority of the subjects responded to the “cognitive cue” condition by changing their voices on the phrase that included “climbed high.” Journal of Voice, Vol. 16, No. 4, 2002
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The subjects also changed their voices in sentence four where overall sentence frequency variability was increased. The increase in variability in this sentence seemed to be primarily due to the effects of the key word “up.” Frequency variability on the key word, on the phrase that included the key word, and on the maximum fundamental frequency used in both the key word and phrase, indicated that the subjects found the movement of a zipper “up” to be a salient cue for voice change. Voice variation on the second phrase, “then down” was not as marked in the “cognitive cue” condition as it was on the first phrase. Movement of a zipper down indicates movement of the zipper back to its original position, perhaps not indicating a downward movement as much as a return to the neutral position of the zipper. Gender differences Gender differences were present and compare well to the data reported in Ferrand and Bloom.4 Results from that study indicated that prepubertal voice differences between males and females begin after ages 7 or 8. The results of the present study indicated that
9 and 10-year-old males and females do differ in frequency variability during reading. However, the Ferrand and Bloom4 data was elicited through spontaneous speech sampling while the tasks in this study utilized written text. Males in the present study had less F0SD than females in both the “no cue” and “cognitive cue” conditions but showed an increase in variability from the “no cue” condition to the “cognitive cue” condition. The “cognitive cue” effects in this study may be due to the relative lack of frequency variability seen in the “no cue” readings. Possible reasons for reduced variability could be due to the subjects’ relative unfamiliarity with the stimulus sentences that not only improved with subsequent readings, but also improved when given the appropriate cognitive cues. However, it does seem that once the children’s imaginations were stimulated and an appropriate instruction was given (suggesting that voice reflect the imagery in the words), the subjects’ variability improved markedly. The subjects did respond to specific cues for frequency and durational changes, but changes in both parameters were evident even when Journal of Voice, Vol. 16, No. 4, 2002
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they were not specifically cued. This suggests the notion that when the imagination is stimulated, the voice reflects natural movement in all parameters. It may also be that some generalization occurs from trial to trial. As is the case with interventions in other areas of speech-language pathology, individual differences were noted. For instance, in sentence one, one subject had consistent difficulty with variation of frequency across the sentence, phrase, and key word. This subject did not respond differently between the “no cue” and “cognitive cue” conditions. With respect to the effect of the specific parameter targeted, there were individual subjects throughout the study who did not respond to any “cognitive cue” conditions. For example, in sentence four, one subject consistently did not respond to cognitive cues for movement. Each of the remaining subjects varied their voices markedly as can be seen from analysis of maximum fundamental frequency and frequency variability measures. When investigating the effect of generalization in the field of phonology, Elbert et al6 found that children often learn more than the target that is taught. It is interesting to note that children demonstrate great variation in their generalization patterns.6 The technique of cognitive cueing provides a way of eliciting natural patterns of voice variability that clinicians cannot model for individual children. Cognitive cueing seems to allow children the freedom to let their voices reflect what the semantic images mean to them. Gierut, Elbert, and Dinnsen,7 have discussed the importance of considering the starting point in phonological treatment with children. They found that children, who were least knowledgeable at the onset of their training, might generalize more dramatically across the sound system. Males in the present study, less naturally variable, became more variable after cueing. Similarly, perhaps the technique of cognitive cueing might be especially helpful for children with specific disorders related to variation of frequency, timing, and intensity such as those seen in the hearing-impaired and developmentally disabled populations. CONCLUSIONS As earlier cognitive cueing studies have indicated, semantic content and imagery may be used to elicit vocal variability. The semantic cues, or the cues embedded in the text, can be highlighted by instructions Journal of Voice, Vol. 16, No. 4, 2002
asking children to imagine what is happening (e.g., actions) or what they are feeling. The cues in this study were limited to the parameters of timing and frequency and both the female and male children responded well to them. Overall, it has been shown that children’s voices do change duration and frequency characteristics when instructions to stimulate their thinking are provided. Furthermore, these children’s voices changed significantly in the direction indicated by both the semantics inherent in the words and in the parameter-specific instructions. This occurred in three of the four sentences. It appears that those sentences and the instructions given were meaningful to this group of school-aged children. One major finding of this study is that the children’s voices were generally more variable when they were cued. Not only were the targeted parameters varied, but other parameters as well. Although there were no significant differences between the frequency levels of “climbed” alone in the “no cue” and “cognitive cue” conditions, there were differences between “climbed high” renditions of the phrase between the trials. This finding reminds us that clinicians must take care to look for changes on more than one word. Future studies will investigate further the interaction of semantically embedded cues and experimenter instructions, the effects of cognitive cueing on children with voice disorders, and the effects of cognitive cueing in eliciting vocal change in the spontaneous speech of school-aged children. REFERENCES 1. Andrews ML, Shrivastav R, Yamaguchi H. The role of cognitive cueing in eliciting vocal variability. J Voice. 2000;14: 494-501. 2. Andrews ML. Voice Treatment in Children and Adolescents. San Diego, Calif: Singular—Thomson Learning; 2001. 3. Andrews ML. Voice Therapy for Children: The Elementary School Years. San Diego, Calif: Singular Publishing Group; 1991. 4. Ferrand CT, Bloom RL. Gender differences in children’s intonational patterns. J Voice. 1996;10;284-291. 5. Milenkovic PH. CspeechSP [computer software]. Madison, WI: University of Wisconsin—Madison: 1997. 6. Elbert M, Dinnsen DA, Swartzlander P, Chin S. Generalization to conversational speech. J Speech Hear Disord. 1990; 55:694-699. 7. Gierut JA, Elbert M, Dinnsen D. A functional analysis of phonological knowledge and generalization learning in misarticulating children. J Speech Hear Res. 1987;30:462-479.
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APPENDIX 1 The subjects were instructed to read each of these sentences silently to themselves, followed by the cognitive cues. 1. The boy walked slowly to school, dragging his feet. Cues: a. “Did you feel how he was walking slowly and dragging his feet? I think that you can make me feel that he was walking slowly even more.” b. “Think about walking slowly and dragging your feet. Think about how you could use your voice to make me feel how he is walking. Use your voice to let me feel the boy walking slowly.” Key word: slowly 2. He ran as fast as he could. Cues: a. “Did you feel how he was running fast? I think that you can make me feel that he was running fast even more.” b. “Think about the boy running as fast as he could. Think about how you could use your voice to make me feel how fast he is running. Use your voice to let me feel the boy running fast.” Key word: fast 3. The plane climbed high in the sky, then dived down. Cues: a. “Did you feel how the plane was climbing and diving? I think that you can make me feel the plane ride even more.” b. “Think about flying up and then down. Think about how you could use your voice to make me feel that feeling. Use your voice to let me feel the plane ride.” Key word: climbed 4. She pulled the zipper up, then down. Cues: a. “Did you feel how the zipper was moving up and down? I think that you can make me feel that she was zipping up and down even more.” a. “Think about zipping your jacket. Think about how you could use your voice to make me feel how the zipper moves. Use your voice to let me feel the zipper moving.” Key word: up
Journal of Voice, Vol. 16, No. 4, 2002