Wrinkles in subsecond time perception are synchronized to the heart

Area of Science:

• Psychology
• Neuroscience
• Physiology

Background:

• The connection between cardiac activity and time perception is a long-standing hypothesis.
• Empirical evidence for the heart's role in subjective time experience is limited.

Purpose of the Study:

• To investigate the relationship between fine-grained cardiac dynamics and the perception of subsecond time intervals.
• To explore how heart rate influences temporal judgments at a millisecond level.

Main Methods:

• Participants completed a temporal bisection task involving brief auditory stimuli synchronized with their heartbeat.
• A novel cardiac Drift-Diffusion Model (cDDM) was developed, integrating heart rate dynamics into a temporal decision-making framework.

Main Results:

• Cardiac dynamics were found to cause "temporal wrinkles," altering the perception of short intervals.
• Lower prestimulus heart rate correlated with perceiving durations as longer, suggesting enhanced sensory intake.
• Higher prestimulus heart rate was linked to faster and more consistent temporal judgments via efficient evidence accumulation.
• Faster poststimulus cardiac deceleration (a marker of attention) was associated with increased sensory temporal evidence accumulation in the cDDM.

Conclusions:

• Cardiac dynamics play a significant role in shaping the momentary experience of time.
• The developed cDDM provides a new methodological approach for studying the heart's influence on time perception and decision-making.