The role of attention in children's time perception

JOURNAL

OF EXPERIMENTAL

CHILD

PSYCHOLOGY

54, 355-371 (1992)

The Role of Attention in Children’s Time Perception DAN ZAKAY Department

of Psychology.

Tel Aviv

University.

Ramat-Aviv.

Israel

This study tested the role of attention in 7- to 9-year-old children’s time estimation. Based on an attentional model of time estimation, it was hypothesized that prospective estimates of short intervals are a function of the degree to which a child is occupied with the passage of time and is focusing his or her attention on estimating the exposure time of a stimulus. Two experiments with two different manipulations on attentional focus were conducted. Eighty children were exposed to two types of light bulbs. one a big bulb kindled with high intensity and the other a small one kindled with low intensity. The light bulbs were kindled for different intervals ranging from 3 to 10 s. In both experiments children estimated the lighting time of the bulbs in each condition by a reproduction method. In the first experiment prospective time estimates were found to be significantly longer than retrospective ones. In the second experiment children gave shorter time estimates when their attention was attracted away from the time estimation task than when it was not. In both experiments the attentional hypothesis was supported. In addition, support for the “more is more” hypothesis was obtained. Implications for understanding children’s time perception processes are discussed. ‘0 IYY? Academx

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The importance of attentional factors in adults’ time perception is well established (e.g., Brown, 1985: Curton & Lordahl, 1974; Underwood & Swain, 1973; Zakay & Tsal, 1989). This is especially true of prospective time estimation of short intervals in which subjects know in advance that they will be asked to estimate the elapsing time (e.g., McClain, 1983). Zakay (1989) and Zakay, Meran, and Ben-Shalom (1989) indicated that prospective time estimations of short durations are typically supportive of an attentional model of time perception (e.g., Hicks, Miller, Gaes, & Bierman, 1977). Retrospective time estimations, in which subjects are notified only when a to-be-estimated interval is terminated that time estimation is required, are more easily explained by Block’s (1990) contextual change model. The author thanks Iris Levin for her helpful comments, and Judith Eisenstark for her help in conducting the study. The author is indebted to two anonymous reviewers for their helpful comments. Reprint requests should be addressed to Dan Zakay. Department of Psychology. Tel-Aviv University. Ramat-Aviv, 69978, Israel. 355

0022-0965192 $5.00 Copyright G 19Y? by Acadcmtc Press. Inc. All rightc of reproduction in any form rcwrvrd

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The attentional model views time estimation as a direct function of the amount of attention that is allocated for processing the passage of time. Frankenhauser (1959) and Priestly (1968) conceptualized the existence of a cognitive timer, which requires mental energy for its “operation.” This energy is obtained whenever one is paying attention to the passage of time. (Attention to the passage of time takes place when one is asking him or herself “what time is it?“, “how long am I doing this?“. “when will this end?“.) Any time such a mental event occurs the content of the cognitive timer is incremented by a unit. Prospective time estimates reflect the number of such units. It is clear. then, that the more attention is devoted to the passage of time, the longer prospective time estimates should be. The level of nontemporal information processing load required during a target interval is another factor beside prospective instructions. which influences the amount of attention allocated for processing the passage of time. As nontemporal information processing load is reduced, more attentional resources may be allocated to the processing of time. The resulting prediction is for a negative relationship between subjective time length and nontemporal information processing load during an estimated interval. A different type of time estimation process is assumed by Block’s (1990) contextual change model. This model claims that time estimation is dependent on the amount of changes, both internal and external, which arc coded and stored in memory due to concurrent information processing. The change model predicts a positive relationship between subjective durations’ length and information processing load, claiming that the deeper and the more complex information processing is. the more contextual, cognitive, and other sort of changes will be observed and coded. The influence of the time measurement paradigm on the nature of subjective time was noted by many scholars (e.g., Block, 1974). Hicks, Miller, and Kinsbourne (1976) suggested that time judgments within a retrospective paradigm are proportional to the amount of content retrieved from an interval rather than to the amount of processing performed during it. Zakay (1990) suggested that in retrospective estimations, an estimator is not aware of the need to pay attention to the passage of time during the target interval. Hence, there is a need to look postfactum for traces of relevant information in order to make time estimations. Under a prospective paradigm, on the other hand, an ongoing awareness of the passage of time exists. and therefore an attentional explanation is relevant. Indeed, the negative relationship between information processing load and estimated duration. as predicted by the attentional model, was verified within the frame of a prospective paradigm (e.g.. Curton & Lordhal, 1974; Hicks & Brandige, 1974; Hicks et al.. 1977: Zakay & Fallach. 1984: Zakay, Nitzan, & Glicksohn. 1983; Zakay et al.. 1989; Zakay and Tsal. 1989). Furthermore. the attentional model was supported by directly manipu-

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lating the amount of attention focused on the passage of time (Zakay, 1989). This was done within a prospective paradigm by using the latent inhibition and the primary-secondary tasks methods. Another experimental paradigm in which the attentional model was supported is the “watched pot” paradigm (e.g., Block, George, & Reed, 1980; Cahoon & Edmonds, 1980; Lordahl & Berkowitz, 1975). Typically, subjects are asked to watch a pot of water until it boils and the watching interval is estimated as longer in comparison to equal control intervals. Generally, the watched pot phenomenon refers to the lengthening of duration experience when one is attentively waiting for some event to occur. It is clear that the watched pot paradigm induces a prospective situation on subjects and that aside from watching, very little nontemporal information processing is required. Hence, this is a pure case in which attentional resources, which are focused on processing the passage of time, influence the experience of time. Block et al. (1980) found that observers in the prospective paradigm, who were presumed to be highly aware of the duration while it was in progress, reproduced the duration as longer than observers in the retrospective paradigm, who were presumed to be less aware of the duration while it was in progress. These findings clearly indicate the difference in attention focusing in the prospective and retrospective paradigms. Children’s time perception is usually treated differently than adults’ time perception. This approach reflects Piaget’s (1969) notion that until the concrete-operational stage, children do not comprehend the interdependence of duration and succession. This notion is debatable as it has been supported in some empirical studies (e.g., Friedman, 1978; Siegler & Richards, 1979), but refuted in others (e.g., Levin, 1977, 1982). Yet, most of the research in this domain focused on problems of children’s time conception rather than on time perception. Nevertheless, evidence for the role of attention in children’s treatment of time were obtained within the frame of time conception research. Typical paradigms in children’s time conception research utilize two partially synchronous events with one beginning before, together, or after the second event, or ending before, together. or after the second event. In these paradigms, children arc asked which of the two events lasted longer. Analyses of performance of such problems (e.g., Levin, 1977; Levin, Gilat, & Zelniker, 1980; Levin, Goldstein, & Zelniker, 1984; Montangero, 1977; Siegler & Richards, 1979). reveal that young children base their comparison of the two events’ durations mainly on the gap in end points while ignoring the gap in beginning points (Levin, Wilkening, & Dembo, 1984). This phenomenon received four explanations: According to the conceptual explanation young children “view duration as a concept referring to a single point, the end point, rather than to an interval that includes both beginning and end points” (Levin et al.. 1980, p. 662). According to the memory lim-

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itation explanation, children fail to remember beginning differences when comparing durations (Levin et al., 1984). The integration limitation explains that “children remember beginnings as well as endings, but fail to integrate both bits of information when inferring the relative durations of two temporal events” (Levin et al., 1984, p. 262). A fourth explanation, the attentional explanation, was proposed by Lcvin et al. (1980). This explanation is based on the claim that due to a recency effect, end points are more salient than beginning points (e.g., Fraissc and Vautrez, 1952; Levin, 1977, 1979) and hence children’s attention is attracted to end points to a higher degree than to beginning points. This attcntional explanation implies that the relative difficulty of problems differing in end points is caused by attentional factors and not because of children’s poor reasoning ability. This claim is in line with Odom’s (1978) perceptual salience model according to which the salience of, or perceptual sensitivity to a given information determines the likelihood of that information being processed. Indeed, the attentional explanation of the end points dominance was supported empirically (Levin et al.. 1980) while the memory explanation was contradicted (Levin et al.. 1984). It should be noted, however, that the paradigms utilized by Levin et al. (1980). did not enable a distinction between the conceptual, the integration, and the attentional explanations. Nevertheless. their findings indicate that attentional factors play an important role in children’s reasoning about time. Several researchers analyzed children’s time perception by offering research paradigms similar to those used in research on adults. Arlin (1986a,b) investigated the appropriateness of the attentional and storage size (Ornstein, 1969) models for children’s time perception by manipulating quantity and depth of processing. It was found that in the context of a prospective paradigm deep processing led to decreased estimation of time and higher quantity led to increased estimation of time. Thus, the conclusion was that aspects of both the storage size and the attentional models were supported. A direct comparison, however. between children’s time perception processes and adults’ processes is not trivial. The reason for that is that a discrepancy bctwcen children and adults might reflect differential influences of contextual variables and visible cues, like quantity. which mislead children but do not influence adults (Arlin. 1986a). A phenomcnon which demonstrates the difference between adults’ and children’s reasoning of time is the “more is more” phenomenon (Levin, 1977, 1979). which is reflected by associating more time with more of typically relevant dimensions. like distance and speed. as well as with more of irrelevant dimensions like size and brightness. Research is therefore needed to directly compare quantity and attentional factors without interference by other factors and especially by information processing load. An appropriate paradigm for this is the watched pot paradigm. The purpose of the present study is to investigate the distinction between

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prospective and retrospective children’s time estimation of short intervals as well as the role of attention in these processes. Two experiments conducted with a paradigm similar to the watched pot paradigm will be reported. In the first experiment, prospective and retrospective time estimations are compared. In the second experiment children’s temporal information processing is disrupted by an attentional manipulation. The impact of this distraction on their prospective time estimates is explored. EXPERIMENT

1: RETROSPECTIVE VERSUS TIME ESTIMATION

PROSPECTIVE

The purpose of experiment 1 is to test the differences between children’s retrospective and prospective time estimation. Retrospective time estimates are assumed to be positively related to the level of nontemporal information processing complexity during a target interval. In contrast, prospective time estimates are assumed to be positively related to the level of attention focused directly on trying to estimate the elapsing time. It is expected, then, that: (1) there should be a difference in length of prospective and retrospective estimates of the durations of same events, and (2) prospective time estimates should be longer than retrospective ones, when all other contextual factors and level of nontemporal information processing load required are kept constant. This control is important because subjective time is a context-dependent variable (Block, 1989; Zakay, 1990). The experiment is conducted by using a watchedpot-like task, in which no particular nontemporal information processing is assumed to be demanded. Hence, the hypothesized differences between prospective and retrospective time estimates are assumed to reflect mainly the different roles of attention in these two processes. Method Subjects. One hundred twelve second- and third-grade school children participated in the study, including an equal number of boys and girls. The ages of second graders ranged from 83 to 88 months with a mean of 84 months. The ages of third graders ranged from 100 to 108 months with a mean of 102 months. The overall mean was 93 months. Instruments. 1. Two red light bulbs varying in size and intensity were utilized. The smaller light bulb, which measured 3.5 cm in width and 1.5 cm in height, possessed a low intensity of 4 pW. The big light bulb measured 6 cm in width and 5 cm in height and had a high intensity of 12 pW. The amount of time each bulb was lit was controlled electronically for periods of 3 or 6 s. The afterglow of the bulbs endured for only a fraction of a second and the difference between the big and small bulbs was negligible in that respect. Each light bulb was placed at a distance of 40 cm from the subject and adjusted such that the subject looked downward at the desired vision angle of 20”.

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2. A simple round battery-operated flashlight with a length of 16 cm, a radius of 4 cm, and an intensity of 1.5 PW was also employed. 3. Finally, an electronic timer with an accuracy of lo- ’ of a second was used in the experiment. The timer was not connected to the flashlight, in order to ensure that the flashlight will look like a common one. Experimental design. Subjects were assigned at random to the following groups with grade and sex equally represented in each group. Eighty subjects were divided equally into four retrospective-prospective groups. The remaining 32 subjects were divided equally into four prospectiveprospective groups. The majority of subjects were allocated to the former groups since the retrospective-prospective comparison was more important for testing the hypotheses than the prospective-prospective comparison. The retrospective-prospective groups. Each child in the retrospectiveprospective groups was tested in two consecutive experimental phases. In the first phase, the light bulb was turned on. Subjects were not told that they would be asked to estimate the light’s duration but were simply asked to watch the light bulb. Hence this first estimation was retrospective. In phase 2, subjects were told in advance that they would be asked later on to estimate the light’s duration and hence estimations were prospective. The bulbs which were used in the four groups were the following: Group I, a big, high-intensity bulb, lit for 3 s, Group 2, a big, high-intensity bulb, lit for 6 s, Group 3, a small, low-intensity bulb, lit for 3 s, Group 4, a small, low-intensity bulb, lit for 6 s. Bulb burning times were manipulated in order to increase the generalizability of the findings. When viewing time estimation as a contextdependent process (Block, 1989), the lengths of an estimated interval is one of the contextual factors which should be considered (e.g., Fraisse, 1984). Studying only one specific duration must limit the generalizability of the conclusions (Arlin, 1989). The prospective-prospective groups. The four prospective-prospective groups were similar to the four retrospective-prospective groups with the exception that, in both phases, subjects were presented with the prospective paradigm. This was done in order to control for order effect between phases 1 and 2 and to test the validity of the attentional manipulation in phase 2. If no significant differences were found between estimations for phases 1 and 2 in the prospective-prospective groups, but such differences were found in the retrospective-prospective groups, with phase 2 estimations being higher than phase 1 estimations, then it would be plausible to claim that this is due to the shift from retrospective to prospective instructions and not to an order effect. Time measurement. Children had to estimate single durations, a task which children were reported to be able to do (Fraisse, 1984; Friedman, 1977). A reproduction method was used by asking subjects to turn on a

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flashlight for the same duration that they thought the light bulb was lit. This method was chosen because it enables a child to estimate duration without demanding the mastering of time units which is a requirement in verbal estimation. The reproduction method is simple and was utilized successfully in previous studies (e.g., Arlin, 1986a,b; Levin et al., 1984; Levin & Wilkening, 1989). The experimenter measured, with the hidden electronic timer, the reproduced durations. Procedure. Each subject was seated in front of the light bulb according to the group to which he or she was assigned. The subject was then told that the experimenter will play with him or her in games of assessing sizes and measurements. Next, the subject was presented with the flashlight and asked to learn how to operate it. Then he or she was asked to estimate the length of a ruler and the weight of the chair upon which he or she was sitting. Then the subject was asked to look at the light bulb in front of him or her. The experiment continued from here through the two phases, according to the group to which the subject was assigned. The prospective instructions were: “Now I’ll turn on the light bulb. You should look carefully to see how long it remains lit and afterwards show me how much time the light bulb burned by turning on the flashlight.” In each phase, after the light bulb was automatically turned off, the reproduction was conducted. Then the instructions for the next phase were given and the experiment continued in the same manner. The retrospective instructions were: “Now I’ll turn on the light bulb, and you should watch it carefully.” After the light bulb was automatically turned off, the experimenter said: “Now I want you to show me, by turning on the flashlight, how much time the light bulb burned.” At the end of the second phase, “prospective” children were thanked and given a candy. “Retrospective-prospective” subjects continued for three more prospective phases, reported in experiment 2. Results

The raw data consisted of the durations of the estimated times (in seconds) reproduced by each subject in each phase. An analysis of variance revealed no significant differences between time estimates of boys and girls or between the two grades. This was expected, since the two grades represented the same stage. No significant interactions were found between sex and grade or between any of them and any other factors. Since the lack of impact of sex and grade was true for the retrospective-prospective as well as the prospective-prospective groups, these two factors were excluded from further analysis for the sake of simplicity and clarity. The means of reproduced times are presented in Table 1. The ratios of reproduced to objective times are also presented in Table 1 in order to provide a standard unit of comparison. A four-way analysis of variance was then performed on the time esti-

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M SD M SD M SD M SD

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TABLE I DUKATI~NS IN SECONDS-EXPERIMENT

Time

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mates with the following factors: (1) group (retrospective-prospective, or prospective-prospective), (2) bulb type (big, high intensity or small, low intensity), (3) burning duration (3 or 6 s), and (4) experimental phase (first or second) with repeated measurements. The main effects of group and phase and their interaction were significant, F(1, 104) = 3.98, 4.12, 4.08, respectively, p < .05; but these variables also interacted significantly with bulb type, F(1, 104) = 6.02, p < .05. Duncan multiple range tests of the between-group differences indicated that in phase 1, in which the groups had different tasks, the time estimates in the prospective-prospective group were significantly longer than in the retrospective-prospective group for the small bulb, p < .Ol, but not for the big bulb, and that in phase 2, in which the groups had the same task, the time estimates were not significantly different for either bulb type. Duncan multiple range tests of the within-group differences, that is, across phases, indicated that the time estimates were significantly longer in phase 2 than in phase 1 for both bulb types in the retrospectiveprospective group, p < .Ol for the small bulb, p < .05 for the big bulb, and were not significantly different in the prospective-prospective group for either bulb type. The only other significant effects were the main effect of burning time, F(1, 104) = 7.33, p < .Ol, and the group by bulb type interaction, F(1, 104) = 5.73, p < .05. In the retrospective-prospective groups time estimates were longer for the big bulb and in the prospective-prospective groups they were longer for the small bulb (Duncan multiple range tests, p < .05.) Discussion of Experiment 1

The results obtained in experiment 1 support the tested hypotheses, although this support is more obvious in the case of the small, low-intensity bulb than in the case of the big, high-intensity one. Prospective time estimates were significantly longer in the prospective phases than in the retrospective ones, as revealed in the analyses of the retrospective-prospective groups. This finding is similar to what is known in adults’ research (e.g., Block, 1992; B rown, 1985). The between-groups analyses revealed a similar pattern of results for the small bulb only. However, the withinsubject analyses are more indicative in this respect than the betweengroups analyses. The finding that prospective time estimates were longer than retrospective ones for the same children is not well explained by an order effect, as the differences between phases 1 and 2 in the prospectiveprospective groups were not significant. A possible explanation for this finding is rooted in the different role attentional processes play in prospective and retrospective time estimations. The present findings are sim-

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ilar to those obtained by Block et al. (1980) who applied a watched pot paradigm to adults. This similarity might indicate that time estimation processes in 7- to 9-year-old children and adults are similar. This hypothesis gained further support by the similarity between magnitude of time estimates in the second phase in the retrospective-prospective and the prospective-prospective groups. This comparison, being a betweensubjects one, should be interpreted cautiously. However, it might indicate that children are engaged with different cognitive processing in the context of retrospective and prospective time estimation. The fact that under all conditions time estimates were longer for burning durations of 6 than of 3 s indicates that children were indeed sensitive to clock time. Support for Levin’s (1977, 1979) “more is more” hypothesis was obtained for the retrospective-prospective groups, where equal burning times of a big, high-intensity bulb were estimated as longer than those attached to a small, low-intensity bulb. However. this was not the case in the prospective-prospective groups. It seems that bulb size and burning intensity had different effects on the retrospective-prospective and the prospectiveprospective groups. This finding is difficult to explain, but it may relate to Block’s (1989) claim that time perception processes can be fully understood only by taking into account high-order interactions among contextual variables. EXPERIMENT 2: THE EFFECT OF ATTENTIONAL DISTRACTION ON CHILDREN’S PROSPECTIVE TIME ESTIMATION

In the first experiment the experimental manipulation was designed to focus attention on temporal information processing. The purpose of experiment 2 was to test the role of attention in children’s prospective time estimation by applying a manipulation in which children’s attention is distracted away from time estimation and temporal information processing. According to the attentional model, this should result in lowering prospective time estimates of similar events without an attentional distraction. Method Subjects. The subjects were the same 80 children who participated in the retrospective-prospective groups of experiment 1. Instruments. The same instruments which were used in experiment 1 were used in experiment 2. In addition, two yellow toys, externally resembling plastic cans, were used. Inside each can was a hidden toy frog. By pressing a button, the frog jumped up noisily for 1.5 s and then came back down again. Experimental design. Four experimental groups participated in the experiment. Every subject in each group participated in three consecutive phases. which were all prospective. The bulbs which were used were

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I, a big, high-intensity bulb, lit for 6 s; Group 2, a big, highintensity bulb, lit for 10 s; Group 3, a small, low-intensity bulb, lit for 6 s; Group 4, a small, low-intensity bulb, lit for 10 s. Bulb burning times were changed in order to eliminate any adaptation on the part of the subjects to burning times used in experiment 1. In addition, it was necessary to increase the burning times because the distraction took 1.5 s by itself. Thus, each child was now exposed to different burning times than those employed in experiment 1. In phase 1, the bulbs were lit without any interruption. In phase 2, the distraction manipulation was activated by the experimenter who pressed the button on the toy can, causing the frog to jump up noisily and then jump back into the box. The box was placed to the side of the light bulb so that if the subject was attracted by the jump, he or she should turn his or her gaze away from the light bulb in the direction of the toy. In all the phases the two identical toys were symmetrically placed to the right and left of the light bulb to ensure an a priori equal level of attraction to both sides. The toy which was actually operated in phase 2 varied between sides in order to counterbalance any possible orientation effects across subjects. In phase 3, the bulbs were lit again without any interruption. This phase served as a comparison condition, allowing assessment of order effects. Time measurement. The same method of time measurement described in experiment 1 was used in experiment 2. Procedure. Experiment 2 was conducted in continuation of experiment 1 and group assignments were not changed. Subjects were exposed to the same bulbs as in experiment 1, but burning times were altered from 3 to 6 and from 6 to 10 s, respectively. In the beginning of each phase, the experimenter gave the prospective instructions, as described in experiment 1. In each phase, after the light bulb was automatically turned off, the reproduction was conducted. At the end of the experiment, the child was thanked and given a candy. Group

Results

The raw data consisted of the durations of the reproduced times (in seconds) made by each subject in each phase. Analysis of variance revealed neither sex nor grade effects, nor any significant interaction between sex, grade, and the three experimental variables. Hence, these factors were excluded from further analyses. The means of the reproduced durations are presented in Table 2. The reproduced durations were subjected to a three-way analysis of variance (bulb type x burning time x experimental phase) with repeated measures in the experimental phase. Three main effects were obtained: (1) experimental phase, F(2, 152) = 4.01, p < .05; (2) bulb type, F(1, 76) = 4.27, p < .05; and (3) burning time, F( 1, 76) = 6.93, p < .Ol. The only significant interaction obtained was between bulb type and burn-

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ing time, F(1, 76) = 3.98, p < .05. Estimated times were higher for the big than for the small bulb (Duncan multiple range test, p < .05). The effect of the distraction manipulation was tested by comparing the reproduced durations in phases 1,2, and 3 by post hoc contrasts (Scheffe), yielding the following significant differences: between phases 1 and 2, F(2, 1.52) = 3.17, p < .05, in which the reproduced times were lower in phase 2, and between phases 2 and 3, F(2, 152) = 5.01; p < .Ol, in which the reproduced times were lower in phase 2. The difference between reproduced times in phases 1 and 3 was not significant, F(2, 152) = 2.98, p = .064. Discussion of Experiment

2

The results obtained in experiment 2 support the attentional model. When attention was distracted from the light bulbs in phase 2, estimations decreased in all groups. When the distraction was eliminated in phase 3, time estimates increased again. The difference between time estimates in the first and the third phase, though not significant, are close to significant with a tendency for time estimates to be longer in the third than in the first phase. Nevertheless, the distraction effect is clear as time estimates in phase 2 are significantly lower than those obtained in either the first or the third phases. The distraction effect clearly illustrates the relationship between attentional focus and children’s immediate prospective duration estimation. A similar finding in adults was obtained by Block et al. (1980, experiments 2 and 3), who used an attentional distraction manipulation and, like this study, this manipulation shortened prospective judgments. It should be mentioned that all the children were attracted to the jumping frog. An order-effect explanation for the difference between phases 1 and 2 is also excluded, because the opposite pattern was found between phases 2 and 3. It should also be pointed out that the more is more effect was further supported in this experiment. GENERAL DISCUSSION The following findings were obtained in the present study: (1) Children’s duration judgments increase with actual duration. This finding indicates that children’s time estimation is sensitive to clock time. (2) Similar to adults, children’s prospective time judgments tend to be longer than their retrospective judgments. (3) An attentional distraction during an estimated interval shortens prospective time reproductions, just as it does adults’ prospective reproductions. These findings indicate that children’s time perception processes are generally similar to those of adults. The findings obtained here can be generally accounted for by assuming that children’s prospective time perception processes are attentional based, while retrospective time perception processes are memory based and dependent on the number of contextual changes occurring during an esti-

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mated interval. This distinction between prospective and retrospective time estimation processes is in place, since a memory-based explanation cannot account for the distraction effect. In the attentional distraction phase, children’s information processing load should be assumed to increase in the face of the surprise they encountered and, undoubtedly, the level of contextual changes is high. Hence, contrary to what was found here, phase 2 time estimates should be higher than those of phases 1 and 3. A memory-based explanation is also not sufficient to explain the results of experiment 1, since the children were asked to look at lights without any requirement for specific nontemporal information processing. The situation was most similar to the watched pot paradigm. The watched pot phenomenon is explained by an expectation model (e.g., Block et al., 1980) which states that while expecting a predefined event to occur, attention is focused on the passage of time and since information processing load is low, duration estimates are higher than those obtained in equal control intervals in which one is not in an expectation condition. The expectation model can be applied in experiment 1. When children are asked to look at a stimulus without any specific requirement for nontemporal information processing, attention is focused on the passage of time, as if the child is asking him/herself “when will this stimulus end‘?” Indeed, children in the first experiment gave longer estimations in the second phase when their attention was directed by means of prospective instructions to the passage of time connected with the lighting of the light bulb, compared to the first phase in which estimations were retrospective. Some words of caution, however. are in place here. The level to which the findings of the present study can be generalized is not clear, since children in the prospective-prospective groups responded differently to bulb size and intensity than did retrospective-prospective children. This reflects the sensitivity of time measurement to context effects. An interesting question which is also associated with context effect is what was the influence of the “measurement games” performed before experiment 1 on children’s time estimation. It is plausible that without these games. the differences between prospective and retrospective time estimates would be even more emphasized than in the present study. The validity of childrens’ time estimates obtained via a reproduction method is most likely not perfect. However. more severe problems are encountered when using other time estimation methods with children. such as the problem of mastering time units, which is required in the method of verbal estimation. Further research should manipulate contextual variables in order to find out to what extent the present findings can be generalized. Another finding of the present study is that equal clock time intervals were, in most cases, estimated to be longer regarding stimulus of higher intensity and larger size, a finding similar to the more is more phenomenon (Levin. 1977, 1979; Levin & Gilat, 1983). The more is more behavior

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was found in both prospective and retrospective time estimations. This evidence favors an explanation of the more is more phenomenon as reflecting children’s logic and reasoning about time rather than the nature of their time estimation processes per se. Children’s time in general can be considered to reflect their time conception, their logic in general, and their time estimation processes. If this is the case, a methodological comment is in place. It seems that traditional paradigms in children’s time perception research, although fruitful, are somewhat limited in their ability to expose all aspects of children’s time perception since their responses are confounded with reasoning problems and biases. Paradigms in which responses more directly reflect time perception processes are required. The role of attention as well as that of information processing in children’s time perception and the similarity between adults’ and children’s time perception processes should be further studied by utilizing research paradigms adapted from adults’ time perception research. REFERENCES Arlin,

M. (1986a). The effects of quantity and depth of processing on children’s time perception. Journal of Experimental Child Psychology, 42, 84-98. Arlin, M. (1986b). The effects of quantity, complexity, and attentional demand on children’s time perception. Perception & Psychophysics, 40(3), 177-182. Arlin, M. (1989). The effects of physical work, mental work. and quantity on children’s time perception. Perception & Psychophysics, 45(3), 209-214. Block, R. A. (1974). Memory and the experience of duration in retrospect. Memory and Cognition, 2, 153-160. Block, R. A. (1989). Experiencing and remembering time: Affordances. context, and cognition. In I. Levi” and D. Zakay (Eds.), Time and human cognition: A life span perspective (pp. 333-360). Amsterdam: Elsevier/North Holland. Block, R. A. (1990). Psychological models of time. In R. A. Block (Ed.). Cognitive models of psychological time (pp. 3-30). Hillsdale. NJ: Erlbaum. Block, R. A. (1992). Prospective and retrospective duration judgment: The role of information processing and memory. In F. Macar, V. Pouthas, and W. J. Friedman (Eds.). Time, action and cognifion. Dordrecht: Kluwer Academic Publishers. Block, R. A., George, E. J.. & Reed, M. A. (1980). A watched pot sometimes boils. A study of duration experience. Acta Psychologica. 46, 81-94. Brown, S. W. (1985). Time perception and attention: The effects of prospective versus retrospective paradigms and task demands on perceived duration. Perception & Psychophysics, 38(2), 115-124. Cahoon, D., & Edmonds, E. D. M. (1980). The watched pot still won’t boil: Expectancy as a variable in estimating the passage of time. Bulletin of the Psychonomic Society, 16(2), 115-116. Curton, E. D., & Lordahl. D. S. (1974). The effects of attentional focus and arousal on time expectations. Journal of Experimental Psychology, 103, 861-867. Fraisse, P. (1984). The adaptation of the child to time. In W. .I. Friedman (Ed.). The developmental psychology of time (pp. 113-140). New York: Academic Press. Fraisse, P., & Vautrez, P. (1952). La perception de I’espace, de la vitesse et du tempts chez I’enfant de 5 ans. II: Le temps. Enface, 1, 102-119.

370

DAN

ZAKAY

Frankenhauser. M. (1959). Estimation of time. Stockholm: Almquist & Wiksell. Friedman, E. R. (1977). Judgments of time intervals by young children. Perceptual & Motor Skills, 45, 715-720. Friedman, W. J. (1978). Development of time concepts in children. In H. Reese & L. P. Lipsitt (Eds.). Advances in child development (Vol. 12. pp. 267-298). New York: Academic Press. Hicks, R. E., & Brandige, R. (1974). Judgments of temporal duration while processing verbal and physiognomic stimuli. Acta Psychologica. 38, 447-453. Hicks, R. E., Miller, G. W., & Kinsbourne. M. (1976). Prospective and retrospective judgments of time as a function of amount of information processed, American Journal of Psychology, 89(4), 719-730. Hicks, R. E., Miller. G. W., Gaes, G., & Bierman, K. (1977). Concurrent processing demands and the experience of time in passing. Americun Journal of Psychology. W(3), 431-446. Levin. I. (1977). The development of time concepts in young children: Reasoning about duration. Child Development, 48, 435-444. Levin, 1. (1979). Interference of time-related and unrelated cues with duration comparisons of young children: Analysis of Piaget’s formulation of the relation of time and speed. Child Development, 469-477. Levin. 1. (1982). The nature and development of time concepts: The effect of interfering cues. In W. J. Friedman (Ed.), The developmental psychology of time (pp. 47-85). New York: Academic Press. Levin, I.. Gilat, I.. & Zelniker. T. (1980). The role of cue salience in the development of time concepts: Duration comparisons in young children. Developmental Psychology, 16(6). 661-671. Levin. I., & Gilat, I. (1983). A developmental analysis of early time concepts: The equivalence and additivity of the effect of interfering cues on duration comparisons of young children. Child Development, 54, 78-83. Levin, 1.. Goldstein, R., & Zelniker, T. (1984). The role of memory and integration in early time concepts. Journal of Experimental Child Psychology, 31, 262-270. Levin, I., Wilkening. F., & Dembo. Y. (1984). Development of time quantihcation: Integration and non-integration of beginnings and endings in comparing duration. Child Development, 55, 2160-2172. Levin, I.. & Wilkening, F. (1989). Measuring time via counting: The development of the concept of time as a quantifiable dimension. In I. Levin and D. Zakay (Eds.), Time and human cognition: A life span perspective (pp. 119-143). Amsterdam: Elsevier/North Holland. Lordahl, D. S.. & Berkowitz. S. (1975). The watched pot does boil: A case of the wrong control group. Bulletin of the Psychonomic Society, 5(l). 45-46. McLain, L. (1983). Interval estimation: Effect of processing demands on prospective and retrospective reports. Perception & Psychophysics, 34(2). 185-189. Montangero. J. (1977). Les relations entre duree et succession: Etude d’une “prelogiquc” enfante applique au temps. L’Annee Psychologique. 81, 287-308. Odom, R. D. (1978). A perceptual-salience account of d’ecalage relations and developmental change. In L. S. Siegel and C. J. Brainerd (Eds.). Alternatives to Piaget: Critical essays on the theory (pp. 127-133). New York: Academic Press. Ornstein, R. E. (1969). On the experience of time. Middlesex, England: Penguin. Piaget, J. (1969). The child’s conception of time. London: Routledge & Kegan Paul. Priestly, J. B. (1968). Man and time. New York: Dell. Siegler, A. S.. & Richards, D. D. (1979). The development of time, speed, and distance concepts. Developmental Psychology. 1.5, 288-298.

ROLE

OF ATTENTION

IN CHILDREN’S

TIME

PERCEPTION

371

Underwood, G.. & Swain, R. A. (1973). Selectivity of attention and the perception of duration. Perceplion, 2, 101-105. Zakay. D. (1989). Subjective time and attentional resource allocation: An integrated model of time estimation. In I. Levin and D. Zakay (Eds.), Time and human cognition: A life spun perspecfive. (pp. 365-395). Amsterdam: Elsevier/North Holland. Zakay, D. (1990). The evasive art of subjective time measurement: Some methodological dilemmas. In R. A. Block (Ed.). Cognitive models of pswholo~ical time (pp. S-84). Hillsdale. NJ: Lawrence Erlbaum. Zakay. D.. & Fdllach. E. (1984). Immediate and remote time estimation-A comparison. Acra Psychologica. 57, 69-81. Zakay, D., Meran. N., & Ben-Shalom, H. (19X9). Cognitive processes of time perception. Psychologica (Hebrew) l(2). 95-103. Zakay, D.. Nitzan. D.. & Glicksohn, J. (1983). The influence of task difliculty and external tempo on subjective time estimation. Perceprion & Psychophysics. 34(S), 451-456. Zakay. D.. & Tsal. Y. (1989). Awareness of attention allocation and time estimation accuracy. Bulletin of the fs.ychonomic Society, 27(3), NY-?lO. RKEIVED:

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