Garry Kong¹ (), Akira Sarodo², Katsumi Watanabe²; ¹Hiroshima University, ²Waseda University

We adapted a working memory paradigm to investigate how attention would affect perception of speed and time. Participants viewed two sequentially presented motion sequences, each consisting of a single ball that entered into a circular area at a random angle, turned and changed speed twice, then exited the area. Motion sequences ranged from 1.3 to 6.8 seconds (mean = 3.5) in duration. Participants were then asked to reproduce the motion sequences by tracing their finger across the circular area. Responses were scored with three methods: 1) by duration, 2) spatially and 3) temporally (e.g., reproducing the spatial midpoint of the sequence at 50% of the reproduction’s duration = no temporal error). To manipulate attention, on 67% of trials, a 75% valid pre-cue was presented before the sequence to bias their attention towards the former or latter motion sequence. We found that participants accurately reproduced the speed and duration of the motion sequence, with mean rank-order correlation between actual and reproduction duration of the motion sequence of 0.566 (0.540 even for cue invalid trials). Unsurprisingly, we found that cue validity increased spatial accuracy and cue invalidity decreased it. More interestingly, we found no evidence that cue validity improved temporal error, only that cue invalidity decreased it. Similarly, no difference in reproduction duration was observed when the cue was valid, only that the reproduced duration was shorter when the cue was invalid. We conclude that inattention reduces the perceived duration of a motion sequence, while simultaneously decreasing the accuracy of the speed of that sequence.

Acknowledgements: Acknowledgements: All authors are supported by the Japanese Society for Promotion of Science Kakenhi (GK: JP22K13874; AS: JP23KJ2029; KW: 22H00090, 24K21505)