Event structure sculpts neural population dynamics in the lateral entorhinal cortex

Area of Science:

• Neuroscience
• Systems Neuroscience

Background:

• The brain must organize continuous sensory input into discrete events across multiple timescales.
• The neural mechanisms for temporal segmentation and organization are not well understood.

Purpose of the Study:

• To investigate the neural basis of temporal organization in the brain.
• To identify how neural population activity segments and encodes events in freely behaving rats.

Main Methods:

• Simultaneous recording of hundreds to thousands of neurons in the lateral entorhinal cortex of freely behaving rats.
• Analysis of neural population dynamics during various behaviors and sleep states.

Main Results:

• Neural population activity exhibited a continuous one-dimensional drift, suggesting an intrinsic origin.
• Discrete shifts in population dynamics at event boundaries segmented neural activity into temporal units.
• Activity orthogonal to the drift encoded event information across multiple timescales during structured tasks.

Conclusions:

• The lateral entorhinal cortex utilizes a hierarchical coding scheme to organize events in time.
• This scheme involves continuous drift for general temporal organization and orthogonal dynamics for event-specific encoding.