Input-output organization of the mouse claustrum

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• The claustrum (CLA) is a subcortical brain structure with poorly understood organization and function.
• Previous research has been limited by challenges in selectively targeting CLA neurons.

Purpose of the Study:

• To overcome targeting limitations and systematically map the inputs and outputs of CLA principal neurons.
• To investigate the connectivity patterns of CLA neurons projecting to the retrosplenial cortex (RSP).

Main Methods:

• Utilized a projection-based targeting strategy to selectively label CLA principal neurons.
• Employed adeno-associated virus (AAV) and monosynaptic rabies tracing techniques.
• Examined pre-synaptic input and axonal output of CLA neurons.

Main Results:

• CLA neurons projecting to RSP collateralize extensively, innervating multiple higher-order cortical regions.
• Sparse subcortical labeling was observed only in the basolateral amygdala (BLA).
• RSP-projecting CLA neurons receive widespread synaptic inputs from cortical and subcortical areas, particularly limbic regions and neuromodulatory systems.

Conclusions:

• CLA neurons exhibit a common targeting scheme across different projection populations.
• The CLA integrates information related to emotional salience.
• The CLA may globally modulate cortical state through uniform output broadcasting to higher cognitive centers.