A scalable population code for time in the striatum.

Area of Science:

• Neuroscience
• Cognitive Science
• Behavioral Biology

Background:

• The brain requires neural signals to represent time across various scales for behavior and learning.
• Neural mechanisms for encoding time, particularly in the seconds-to-minute range, remain largely unknown.
• The striatum, a basal ganglia region, is implicated in learning, motor function, and timing behavior.

Purpose of the Study:

• To investigate how neural signals in the striatum encode time intervals.
• To determine the role of striatal neuronal activity in interval timing behavior.
• To explore if striatal populations can represent relative time and adapt to changing temporal demands.

Main Methods:

• Recorded neuronal activity from striatal neurons in rats performing an interval timing task.
• Analyzed neuronal firing patterns in relation to elapsed time and the animals' sensorimotor state.
• Decoded time estimates from neural activity and assessed the impact of disrupting striatal function on timing performance.

Main Results:

• Found striatal neurons fired at delays spanning tens of seconds, reflecting an interaction between time and sensorimotor state.
• Observed that neuronal responses were rescaled in time when interval durations changed, indicating a relative time code.
• Demonstrated that decoded time estimates predicted behavioral adjustments, and striatal disruption impaired timing.

Conclusions:

• Striatal neuronal populations form a scalable code for representing time.
• This striatal timing code provides signals crucial for guiding animal behavior and adapting to changing temporal intervals.
• The findings elucidate a neural mechanism within the basal ganglia for interval timing.