Striatal topographical organization: Bridging the gap between molecules, connectivity and behavior.

Area of Science:

• Neuroscience
• Neuroanatomy

Background:

• The striatum, a key basal ganglia component, receives cortical input and is vital for complex behaviors.
• Its topographical organization remains incompletely understood despite extensive research.
• Understanding striatal organization is crucial for deciphering its role in neuropsychiatric diseases.

Purpose of the Study:

• To review current knowledge on striatal organization, linking structure to function.
• To explore how striatal organization is altered in neuropsychiatric disorders.
• To bridge the gap between macroscopic and molecular levels of striatal anatomy.

Main Methods:

• Review of studies across species utilizing diverse methodologies.
• Includes tract-tracing, immunohistochemistry, neuroimaging, and transcriptomics.
• Focus on integrating findings from different spatial and molecular scales.

Main Results:

• The striatum exhibits a continuum at the mesoscale with subtle histochemical and gene expression differences.
• Cortico-striatal projections show topographical organization supporting functional domains (motor, cognitive, affective).
• Evidence suggests a gradient-like organization rather than sharply defined territories.

Conclusions:

• Striatal organization is complex, with functional heterogeneity supported by diverse afferent connections.
• Molecular and cellular underpinnings of this organization and its behavioral relevance require further investigation.
• This review synthesizes current understanding and highlights future research directions.