A New Illusion of Time Perception—II

Abstract

When one very short empty time interval follows right after another, the second one can be underestimated considerably, but only if it is longer than the first one. We coined the term "time-shrinking" for this illusory phenomenon in our previous studies. Although we could relate our finding to some studies of rhythm perception, we were not able to explain the illusion. The present article presents our attempt to understand the mechanism that causes the time-shrinking. Four experiments are reported. The first one ruled out the possibility that the illusion results from a difficulty in resolving the temporal structure. The second experiment showed that the listener was not inadvertently judging the duration of the first interval instead of that of the second one. In addition, this experiment yielded more information about the time window within which the illusion occurs. The third experiment showed that forward masking of the sound markers, delimiting the empty durations, could not explain the illusion either. Furthermore, this experiment revealed a clue to the mechanism of time-shrinking: competition between expected and observed temporal positions. The fourth experiment further examined the temporal conditions that give rise to the illusion and showed that categorical perception plays a crucial role in the formation of the illusion. In the general discussion, we argue that the illusion is due to an asymmetric process of temporal assimilation.

Auditory Time-Interval Perception as Causal Inference on Sound Sources

“…In addition, though the degrees of misestimation are not so large as those for the case of the time-shrinking illusion, the following phenomena on the perception of T 2 have also been observed (Miyauchi and Nakajima, 2005; Figure 1A): overestimation of T 2 when T 2 is a little shorter than T 1 ; underestimation of T 2 when T 2 is much shorter than T 1 ; and overestimation of T 2 when T 2 is much longer than T 1 . The time-shrinking illusion has been examined in other articles as well (Nakajima et al, 1992; ten Hoopen et al, 1993, 2006; Suetomi and Nakajima, 1998; Miyauchi and Nakajima, 2007; Mitsudo et al, 2009). Furthermore, it was reported that this phenomenon occurs in other sensory modalities such as visual (Arao et al, 2000) and tactile (van Erp and Spapé, 2008) senses.…”

Time-shrinking, its propagation, and Gestalt principles

“…The robustness and the stability of this illusory phenomenon have been shown in various experimental situations and with huge variations of the sound markers that delimited the durations (e.g., Remijn et al, 1999;Suetomi & Nakajima, 1998;ten Hoopen et al, 1995). In earlier studies from our laboratories, several possible explanations were ruled out, and the Gestalt notion of assimilation was introduced as a first step toward elucidating the mechanism of TS (Nakajima, ten Hoopen, Hilkhuysen, & Sasaki, 1992;Nakajima, ten Hoopen, & van der Wilk, 1991;ten Hoopen et al, 1993). Recently, Sasaki, Nakajima, and ten Hoopen (1998) offered clear evidence that the temporal assimilation indeed takes place and that it is basically unilateral-that is, it was shown clearly that the duration of the second empty time interval (t2) assimilated to the shorter duration of the first interval (t1), whereas assimilation in the opposite direction happened only slightly, if ever.…”

Discriminating time intervals presented in sequences marked by visual signals

“…Depending on several factors, such as the range of durations under investigation and the interstimulus interval (ISI), duration may be severely underestimated or overestimated. Recently, Nakajima, ten Hoopen, and collaborators have offered a series of studies showing that the presentation of sequences of successive intervals produces an impressive TOE that they called a time shrinking illusion (Nakajima, ten Hoopen, Hilkhuysen, & Sasaki, 1992;Nakajima, ten Hoopen, & van der Wilk, 1991;ten Hoopen et al, 1993). For instance, in the continuous method described earlier, the last interval of a series should last about 78 msec in order to be perceived to be as long as the preceding 50-msec standard intervals.…”