Higher-Order Thalamic Circuits Channel Parallel Streams of Visual Information in Mice

Area of Science:

• Neuroscience
• Thalamic Nuclei Research
• Visual System Function

Background:

• Higher-order thalamic nuclei, like the visual pulvinar, are crucial for cortical function.
• The pulvinar's complex anatomy and diverse cognitive roles hinder a unified functional framework.

Purpose of the Study:

• To dissect the function of the lateral posterior thalamic nucleus (LP), a mouse pulvinar homolog.
• To establish a framework for understanding higher-order thalamic nuclei in vision.

Main Methods:

• Large-scale anatomical circuit mapping in mice.
• High-density electrophysiological recordings.
• In vivo manipulation of visual cortex and superior colliculus inputs.

Main Results:

• Defined three LP subregions based on connectivity and function.
• Identified LP subregions forming corticothalamic loops targeting ventral or dorsal visual streams.
• Demonstrated distinct LP subregions driven by visual cortex versus superior colliculus inputs.
• Showcased separate representations of visual space within LP subregions.

Conclusions:

• The LP is organized into functionally distinct subregions based on input sources and downstream targets.
• This study provides a roadmap for elucidating higher-order thalamic mechanisms in visual processing.