Changes in apparent duration follow shifts in perceptual timing

Area of Science:

• Visual perception
• Psychophysics
• Cognitive neuroscience

Background:

• Apparent duration of moving objects increases with speed.
• The influence of acceleration and deceleration on perceived duration is not well understood.

Purpose of the Study:

• To investigate the effects of acceleration and deceleration on the perceived duration of a drifting visual grating.
• To determine how speed changes, rather than average speed, influence duration perception.

Main Methods:

• Participants viewed a drifting grating with constant average speed (10°/s) but varying acceleration/deceleration profiles.
• Perceived duration was compared across conditions with increasing, decreasing, or constant speed.
• Apparent motion direction and temporal impulse response were also assessed.

Main Results:

• Increasing speed progressively compressed perceived duration, proportional to speed range, not acceleration.
• Decreasing speed moderately increased perceived duration, showing asymmetry.
• Duration changes correlated with adaptive shifts in visual filters, potentially linked to flicker adaptation.

Conclusions:

• Perceived duration is significantly modulated by speed changes, with asymmetric effects for acceleration and deceleration.
• These findings suggest a shared neural mechanism for processing visual motion and temporal duration.
• Adaptive changes in visual filters may underlie the observed effects on perceived duration and motion direction.