Cell-type-specific cholinergic control of granular retrosplenial cortex with implications for angular velocity coding...

Area of Science:

• Neuroscience
• Computational Neuroscience

Background:

• Cholinergic receptor activation influences cortical pyramidal neuron firing, crucial for spatial navigation theories.
• The granular retrosplenial cortex (RSG) plays a vital role in spatially-guided behaviors, but the effect of acetylcholine on its neurons remains unclear.

Purpose of the Study:

• To investigate the impact of acetylcholine on neurons within the granular retrosplenial cortex (RSG).
• To identify distinct neuronal subtypes in the RSG and characterize their responses to cholinergic stimulation.

Main Methods:

• Transcriptomic, morphological, and biophysical characterization of RSG neuronal subtypes.
• Electrophysiological recordings to assess neuronal firing patterns in response to cholinergic agonists.

Main Results:

• A distinct RSG cell-type, low-rheobase (LR) neurons, exhibits a unique cholinergic muscarinic receptor expression profile.
• Unlike other RSG principal neurons, LR neurons do not fire persistently when exposed to cholinergic agonists.
• This lack of persistent firing enables LR neurons to rapidly compute angular head velocity (AHV) independently of cholinergic fluctuations.

Conclusions:

• LR neurons possess specialized properties for consistent angular head velocity (AHV) computation across varying brain states.
• These findings highlight specialized neural codes within the RSG that support spatial navigation.