Striosome

Neuroanatomical structure in the brain

Striosome

The striosome, also known as the striosomal compartment, is a distinct anatomical and functional region within the striatum, a subcortical part of the forebrain. The striosome is characterized by its unique neurochemical composition and connectivity, distinguishing it from the surrounding matrix compartment.

Striosomes and matrix compartments in the striatum

Anatomy

The striosomes are patch-like structures that are interspersed within the matrix of the striatum. They are identifiable by their high levels of mu-opioid receptor binding and distinct patterns of neurotransmitter expression. The striosomes are rich in substance P and enkephalin, which are neuropeptides involved in modulating dopaminergic activity.

Function

Striosomes play a crucial role in the regulation of dopamine signaling within the striatum. They receive input from the prefrontal cortex and are involved in processing reward and emotion. The striosomal compartment is thought to influence decision-making processes and the evaluation of risk and reward.

Connectivity

Striosomes have distinct connections compared to the matrix. They project to the substantia nigra pars compacta, influencing dopaminergic neurons that project back to the striatum. This forms a feedback loop that is essential for the modulation of motor and cognitive functions.

Development

During embryonic development, striosomes are among the first structures to form within the striatum. They are believed to guide the development of the surrounding matrix and establish the initial framework for striatal organization.

Clinical Significance

Alterations in striosomal function have been implicated in various neurological disorders, including Parkinson's disease, Huntington's disease, and Tourette syndrome. Dysregulation of striosome-matrix interactions may contribute to the motor and cognitive symptoms observed in these conditions.

Research

Ongoing research aims to further elucidate the role of striosomes in neuropsychiatric disorders and their potential as targets for therapeutic intervention. Advanced imaging techniques and genetic models are being used to study the specific contributions of striosomes to brain function.

Related pages

• Striatum
• Basal ganglia
• Dopamine
• Substantia nigra