The neural representation of time distributed across multiple brain regions differs between implicit and explicit...

Area of Science:

• Neuroscience
• Cognitive Science
• Chronobiology

Background:

• Animals exhibit internal timing mechanisms for actions.
• Neural basis of time perception, especially for durations of seconds to minutes, is not well understood.

Purpose of the Study:

• To explore the neural representation of time perception.
• To elucidate the mechanisms underlying the brain's internal clock.

Main Methods:

• Review of existing evidence on neural correlates of time perception.
• Analysis of two proposed neural encoding methods for time: single neuron firing rate modulation and neural ensemble sequential activity.

Main Results:

• Time perception relies on two neural encoding strategies: firing rate modulation and sequential neural activity.
• These mechanisms are observed in brain regions including the hippocampus, entorhinal cortex, medial prefrontal cortex, and dorsal striatum.
• Neural activity reflects relative, not absolute, time, functioning akin to a clock.

Conclusions:

• Two distinct internal timing systems operate across multiple brain regions.
• These systems are engaged based on whether time duration is implicitly or explicitly perceived.
• Simultaneous engagement of these timers supports accurate time perception under various conditions.