File:Basal Ganglia Go and NoGo Pathways.jpg

English: In this figure, basal ganglia GO pathways are shown in blue, and they are selecting the “blue” emulation, while NO GO pathways are shown in yellow deselecting the “yellow” emulation. Arrows that are outlined in black denote an excitatory connection, while red-outlined arrows represent an inhibitory connection. Pathway 1 is a NO GO pathway that includes an inhibitory connection from the striatum to the globus pallidus externus (GPe), an inhibitory connection from the GPe to the globus pallidus internus (GPi), and an inhibitory connection to the thalamus. Pathway 2 is a GO pathway that has an inhibitory connection from the striatum to the GPi, and an inhibitory connection from the GPi to the thalamus. Pathway 3 is a NO GO pathway that contains an inhibitory connection from the striatum to the GPe, an inhibitory connection from the GPe to the subthalamic nucleus (STn), an excitatory connection from STn to GPi, and an inhibitory connection from GPi to thalamus. Pathway 4 is a GO pathway that has an inhibitory connection from the striatum to the substantia nigra pars reticulata (SNr), and an inhibitory connection from SNr to thalamus. Instead of starting in the striatum, Pathway 5 is a NO GO pathway that includes an excitatory connection directly from cortex the STn, an excitatory connection from STn to GPi, and an inhibitory connection from GPi to thalamus. Note that the pathways shown are just a selected subset of all the possible pathways information can travel through the basal ganglia in a cortical-basal ganglia-thalamo-cortical loop. See Schroll and Hamker (2013) for a review of basal ganglia pathways.