In the cerebellum and basal ganglia, projection neurons are GABAergic; but in the cerebral cortex, there has been a historically strong dichotomy between glutamatergic projection neurons and GABAergic local circuit neurons. While this dichotomy is overwhelmingly the case, it is now clear that a small population of long-distance projecting GABAergic neurons (positive for somatostatin and nNOS, and negative for parvalbumin) occurs in primates, as well as in cats and rodents. Beyond their well-documented existence, however, the functional significance, ontogeny, and connectivity of this intriguing subpopulation remain obscure.
In the cerebellum and basal ganglia, projection neurons are GABAergic; but in the cerebral cortex, there has been a historically strong dichotomy between glutamatergic projection neurons and GABAergic local circuit neurons. While this dichotomy is overwhelmingly the case, it is now clear that a small population of long-distance projecting GABAergic neurons (positive for somatostatin and nNOS, and negative for parvalbumin) occurs in primates, as well as in cats and rodents. Beyond their well-documented existence, however, the functional significance, ontogeny, and connectivity of this intriguing subpopulation remain obscure.
