Mapping the topographic organization of the human zona incerta using diffusion MRI

Area of Science:

• Neuroscience
• Brain Connectivity
• Neuroimaging

Background:

• The zona incerta (ZI) is a deep brain structure implicated in various functions.
• Evidence suggests the ZI is a potential target for neuromodulation.
• Its precise organization and connectivity remain incompletely understood.

Purpose of the Study:

• To investigate the topographic organization of the zona incerta (ZI) and its connectivity with the neocortex.
• To identify specific ZI subregions and their cortical connections.
• To inform the development of ZI-based neuromodulatory strategies.

Main Methods:

• Utilized in vivo diffusion MRI for data-driven connectivity analysis.
• Applied clustering and gradient approaches to map ZI organization.
• Validated findings across multiple datasets and at the individual subject level.

Main Results:

• Identified a rostral-caudal topographic gradient within the ZI.
• Demonstrated specific connections between rostral ZI and frontopolar/ventral prefrontal cortices.
• Showed connections between caudal ZI and primary sensorimotor cortices.
• Mapped a central ZI region connected to the dorsal prefrontal cortex.

Conclusions:

• The ZI exhibits a clear topographic organization with the neocortex.
• This organization supports the ZI's role in mediating motor, cognitive, and emotional control.
• Findings provide a foundation for refining ZI neuromodulation targets.