Developmental study of time, space and velocity estimations. V. The set for the use of cue in space perception

Abstract

The effects of time and velocity on space estimation in the field of motion perception are not always the same as tau-effect observed in successive on and off of static stimuli (see Table 1). We try to interpret the facts in terms of the hypothesis that in the field of motion perception the set in estimating space to use rather velocity than time as a cue may be easily formed whereas in the case of the static stimuli the set in estimating space to choose velocity as a cue may be almost impossible to be formed. As space varies directly proportionally to velocity and also to time, an anti-tau-effect may rather be expected in the moving stimulus whereas in the static stimuli a tau-effect may mainly be expected. But in the motion perception the tau-effect may also be expected under the special conditions where the set in estimating space to use time as a cue to be easily formed. In the developmental view-point, as it may be more difficult for young children to use time as a cue in estimating space than to use velocity as a cue because of the invisible quality of time, it may be expected for them to show stronger anti-tau-effect than for adults. The present experiment is so designed as to examine the effects of the two sets in space estimation in the field of motion perception.For space estimation a reproduction method is used. Standard stimuli shown in Table 2 consist of the four series, each of which contains five standard spaces common to all series. In each series the condition of standard space 4.0cm is the main condition to examine whether the effect is tau or not, and the other four conditions are additional to form a certain set. As the main condition and one of the additional conditions are alternately presented, reproduced spaces are obtained four times for the main condition and only one reproduced space is obtained for each additional condition.The types and number of subjects are designated in Table 3.The main results are as follows:1. Reproduced spaces under series VLS are generally smaller than those under series VSL, especially in the younger children. This effect is opposite to tau-effect, and as under these series space changes directly proportionally to velocity and time is constant, it is supposed that the set in estimating space to use velocity as a cue is relatively strongly formed (see Figs. 1, 2 and 3, and Tables 4, 5, 6, 7, 9 and 10).2. Reproduced spaces under the series TLS are generally a little larger than those under series TSL, especially in the adults. This effect is the same as a tau-effect, and as under these series space changes directly proportionally to time and velocity is constant, it is supposed that the set in estimating space to use time as a cue is relatively strongly formed (see Figs. 1, 2 and 3, and Tables 4, 5, 6, 7, 9 and 10).From the findings described above, we may conclude that the effect of time on space estimation in terms of static stimuli and the effects of time and velocity on space estimation in terms of moving stimulus can equally be interpreted by the hypothesis of sets to choose cues in space estimation, just as in time estimation (Matsuda, 1970a).These findings also make sure that velocity may work more easily as a cue in space estimation than time for young children.4. Relations between standard space (x) and reproduced space (y) are nearly linear under all series, and in regression lines (y=ax+b)b is larger, as the subjects are younger. And the correlation coefficients between 4 trials for the main conditions are smaller, as the subjects are younger. It is thus suggested that reproduction of space may be more difficult for younger children because some degree of sensory-motor learning is necessary for them to reproduce space well (see Tables 8 and 10).