Cortex-basal ganglia-thalamus-cortex circuit in mice.

Sagittal sketch of representative structures involved in the circuit. A) Cortex neurons transmit glutamate to the striatum and subthalamic nucleus. Striatum interneurons transmit acetylcholine. B) The striatum transmits GABA to the globus pallidus externa, globus pallidus interna, and substantia nigra reticulata. The globus pallidus externa transmits GABA to the subthalamic nucleus, globus pallidus interna, and substantia nigra reticulata. The subthalamic nucleus transmits glutamate to the globus pallidus interna and substantia nigra reticulata. The substantia nigra pars compacta transmits dopamine to the striatum where some terminals synapse on upregulating receptors and some on downregulating receptors. C) The globus pallidus interna and substantia nigra reticulata transmit GABA to the thalamus. D) The thalamus transmits glutamate to the cortex. While these structures and chemicals do not exist in isolation, dysregulation of any of these molecules may have reverberating effects on the entire circuit. [Figure created with information from Conn et al. (2005) [19], Arnsten and Rubia (2012) [51], and the Allen Mouse Brain Atlas [52].]