A previous study [Gerbino, 1997, in Human and Machine Perception Eds Cantoni et al (New York: Plenum Press) pp 147 ^ 154], in which the launch effect was used [Michotte, 1963 The Perception of Causality (London: Methuen)] shows that auditory information affects visual discrimination. Here I investigated the role of audio-visual congruence in time in discrimination of visual events. In the first experiment, a sequence of two continuous sounds (523 and 659 Hz) accompanied the visually moving objects. Two different time gaps (0 or 40 ms) between the stopping of the first moving object and the start of the second one and three different pauses (0, 40, or 200 ms) between the two sounds were used. Participants were asked to discriminate the events only visually. The signal detection theory was adopted. Data analysis showed that the performance of visual discrimination is worse when the auditory information is physically congruent with the visual event. When the pause between the two sounds is 200 ms, the performance improves. In the second experiment I used an undiscriminable visual time gap (0 or 10 ms) to demonstrate that auditory information is not enough to improve the performance. I conclude that the visual discrimination is largely influenced by the global structure of events.
The role of audio-visual congruence in discrimination of visual events
SINICO, MICHELE
2004
Abstract
A previous study [Gerbino, 1997, in Human and Machine Perception Eds Cantoni et al (New York: Plenum Press) pp 147 ^ 154], in which the launch effect was used [Michotte, 1963 The Perception of Causality (London: Methuen)] shows that auditory information affects visual discrimination. Here I investigated the role of audio-visual congruence in time in discrimination of visual events. In the first experiment, a sequence of two continuous sounds (523 and 659 Hz) accompanied the visually moving objects. Two different time gaps (0 or 40 ms) between the stopping of the first moving object and the start of the second one and three different pauses (0, 40, or 200 ms) between the two sounds were used. Participants were asked to discriminate the events only visually. The signal detection theory was adopted. Data analysis showed that the performance of visual discrimination is worse when the auditory information is physically congruent with the visual event. When the pause between the two sounds is 200 ms, the performance improves. In the second experiment I used an undiscriminable visual time gap (0 or 10 ms) to demonstrate that auditory information is not enough to improve the performance. I conclude that the visual discrimination is largely influenced by the global structure of events.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
