Assembly and diversity of long-range inhibitory circuits in the brain

The mammalian neocortex hosts some of the most complex neural circuits in the brain. These typically consist of two main types of nerve cells excitatory projection neurons which deliver informationto other cells over long distances using the neurotransmitter glutamate, and inhibitory interneurons that provide local inhibition bysecreting the neurotransmitter GABA. How these cortical circuits compute information remains largely unknown, but most current models of cortical processing are predicated on the basic tenet thatoutput neurons the cells that relay processed information to other cortical or brain regions are excitatory glutamatergic neurons, andtheir activity is fine-tuned locally by GAGAergic interneurons.