時間評価の発達III

標準時間中および再生時間中の音の頻度の効果

抄録

The purpose of the present experiment was to examine developmentally the effects of the frequency of intermittent sounds, given during the standard time of 6 sec and during the reproduced time, on the length of the reproduced time by the method of reproduction. The number of conditions of intermittent sounds were seven as shown in Table 1. To each subject these seven conditions of frequencies of sounds were presented three times each at random. Besides, the tempo of the metronome which was preferred by the subject as most comfortable was measured individually, and the relation of the tempo with the reproduced time was examined. The subjects were as shown in Table 2.
Results were as follows.
1. Generally, when the sounds were given during the standard time, as the frequency of sounds increased, in other words, as the sound interval decreased, the reproduced time became longer, and when the sounds were given during the reproduced time, as the frequency of sounds increased, the reproduced time became shorter (see Table 4). These findings support the law by Fraisse: “Tout ce qui contribue à augmenter ou à diminuer le nombre des changements remarquès a pour effet d'allonger ou de raccourcir la durée apparente”.
The younger were the subjects, the stronger was the effect of sounds. However, the effect was not statistically significant for adults (see Fig. 1).
The effect of sounds during the standard time was weaker than that during the reproduced time (see Fig. 1). This result shows that the sounds during the reproduced time have more direct effect on the time estimation. One reason for it may be that the estimation is done during the reproduced time, not during the standard time.
2. The effect of no sounds during either time did not fall between the effect of the sounds during the standard time and the effect of the sounds during the reproduced time (see Fig. 1). And the developmental trend of the length of the reproduced time under the condition of no sounds during either time was similar to that under the condition of low frequency sounds during the standard time and that under the condition of high frequency sounds during the reproduced time (see Fig. 2).
These findings support the hyposesis that the time estimation is based on the personal tempo, and during the reproduction the frequency of perceived change (changements remarqués) based on the personal tempo is higher than during the standard time for young children because of their impatience. It seems that in young children the tempo of the intermittent sounds absorbs the personal tempo and both tempos are likely to become one, so the effect of the intermittent sounds is stronger for them (see Fig. 3).
3. In general, the reproduced time of young children who preferred fast metronome tempos was longer (see Table 6), and they showed clearer tendency to est imate the time with sounds of high fre quency as shorter than the time with sounds of low frquency (see Table 7). It appears that the young children who have fast metronome tempos aree more susceptible to the influence of sounds.