Intercalated cells of the amygdala mPFC) in both primates and rodents, which may explain cortical control over emotional regulation processes such as extinction. Intercalated cells of the amygdala The intercalated (ITC) cells of the amygdala are a group of GABAergic neurons situated between the basolateral and central nuclei of the amygdala that are important for inhibitory control over the amygdala. ITC cells are thought to play a role as the 'off switch' for the amygdala, inhibiting the amygdala's central nucleus output neurons and its basolateral nucleus neurons. Some researchers speculate that ITC cells, via their extensive local inhibition within the amygdala, could serve as a
Intrinsically photosensitive retinal ganglion cells able to isomerize "all-trans-"retinal into "11-cis-"retinal when stimulated with light without help from additional cells. The two isoforms of melanopsin differ in their spectral sensitivity, for the "11-cis"-retinal isoform is more responsive to shorter wavelengths of light, while the "all-trans" isoform is more responsive to longer wavelengths of light. ipRGCs are both pre- and postsynaptic to dopaminergic amacrine cells (DA cells) via reciprocal synapses, with ipRGCs sending excitatory signals to the DA cells and the DA cells sending inhibitory signals to the ipRGCs. These inhibitory signals are mediated through GABA which is co-released from the DA cells along with dopamine.