Ajustements Correctifs et Perception De L’ordre Temporel

Abstract

[Corrective Adjustments and Temporal Order Perception] Does perception of temporal order benefit from knowledge of results in a task where subjects have to judge the order of visual and auditory stimuli presented al short intervals? Stimuli were separated by temporal intervals selected in accordance with a constant stimuli rule. Two classical measures were taken : - the point of subjective simultaneity (P.S.S.) and - the just noticeable difference (J.N.D. = D.J.P. in French). The first one gives an estimation of how closely objective and subjective simultaneity are related. The second one is informative about the accuracy of temporal order perception. Comparisons were made between series of trials which precede trials blocks where information about correctness of temporal order judgments (T.O.J.) was given and scries which were following those trials blocks. As a complementary indication, the P.S.S.-movements between the critical scries were considered to tell us whether corrections were actually performed or not. Averaged results did not show any influence of knowledge of results on T.O.J.’s: mean P.S.S.’s and mean J.N.D.’s remained unaffected. Feedback information could however have been used, and led in most of these cases (which arc more than half of the subjects sample) to small adjustments of the perceived simultaneity. Nevertheless, accuracy of temporal order perception was not improved after knowledge of results.