Striosome

Striosome (also known as striosomal compartment) is a specialized region within the striatum, a subcortical part of the forebrain. The striosome is characterized by its distinct neurochemical composition and connectivity compared to the surrounding matrix compartment.

Structure

The striosome is one of the two main compartments of the striatum, the other being the matrix. These compartments are distinguishable by their different patterns of neurotransmitter receptors, neuropeptides, and gene expression. Striosomes are rich in mu-opioid receptors, substance P, and enkephalin, whereas the matrix contains higher levels of calbindin and acetylcholinesterase.

Function

Striosomes play a crucial role in the modulation of motor control, cognition, and emotion. They receive input from the prefrontal cortex, limbic system, and thalamus, and project to the substantia nigra pars compacta. This connectivity suggests that striosomes are involved in the integration of emotional and cognitive information with motor functions.

Development

During embryonic development, striosomes and the matrix compartment emerge from the ganglionic eminence. The differentiation of these compartments is influenced by various transcription factors and signaling pathways.

Clinical Significance

Dysfunction in the striosomal compartment has been implicated in several neurological disorders, including Huntington's disease, Parkinson's disease, and Tourette syndrome. Abnormalities in striosome function can lead to deficits in motor control and emotional regulation.

Research

Ongoing research aims to further elucidate the specific roles of striosomes in the basal ganglia circuitry and their involvement in neuropsychiatric disorders. Advanced techniques such as optogenetics and in vivo imaging are being used to study the dynamic functions of striosomes.

See Also

• Striatum
• Basal ganglia
• Substantia nigra
• Neurotransmitter
• Neuropeptide