Corticostriatal Projections Sample Clauses

Corticostriatal Projections. The massive glutamatergic projection from the cortex into the striatum terminates on the heads of MSN spines. These projections are organized in a highly topographic manner in the striatum. Corticostriatal innervation is further organized into a parallel functioning architecture (Alexander et al., 1990). Corticostriatal projections are segregated into circuits that process different types of information such as skeletomotor, oculomotor, associative, and limbic. The motor loop comprises information from the primary motor cortex (MC), the arcuate premotor area (APA), premotor cortex (PMC), primary somatosensory cortex (SI), and supplementary motor are (SMA). The oculomotor loop encodes the input from the frontal and supplementary eye fields, the associative loop encompasses the signals from the prefrontal and lateral orbitofrontal cortex, and limbic loop involves the anterior cingulated and medial orbitofrontal cortex areas (Alexander et al., 1990). The cortical pyramidal neurons projecting to the striatum are located in layers II-VI, but the most projections come from layer V (Xxxxxx and Xxxxxxx-Xxxxx, 1999). There is evidence for convergence and segregation among the corticostriatal information. All these projections target the heads of spines of MSN in both the direct and indirect pathway.