Time is a rubberband: neuronal activity in monkey motor cortex in relation to time estimation

Area of Science:

• Neuroscience
• Cognitive Science
• Motor Control

Background:

• Anticipating events is vital for motor performance.
• Reaction times vary even with constant delay durations in instructed delay tasks.
• Variability in time estimation increases over time due to the scalar property of time estimation.

Purpose of the Study:

• To investigate the correlation between neuronal delay activity and subjective time estimation.
• To explore how temporal prior information influences neuronal activity in the motor cortex.
• To determine if normalizing neuronal discharge variability aligns with subjective time perception.

Main Methods:

• Utilized instructed delay tasks with two randomly presented, equally probable delay durations.
• Recorded neuronal activity in the monkey motor cortex.
• Rescaled spike times based on the subjective duration between instruction and movement onset to normalize across trials.

Main Results:

• Across-trial variability in neuronal discharge decreased after rescaling spike times.
• The increasing variability in neuronal activity during the delay period was eliminated.
• Neuronal peak discharge timing variability did not increase during the trial post-rescaling.

Conclusions:

• Neuronal delay activity directly correlates with subjective time estimation.
• The motor cortex exhibits an 'elastic' temporal profile reflecting subjective time perception.
• Findings suggest that the brain adjusts neuronal timing to match perceived time intervals.