Dr. Adam Kepecs led a group of a team of neuroscientists at Cold Spring Harbor Laboratory that is the first to elucidate a class of inhibitory neurons that specialize in inhibiting the action of other inhibitory neurons. The research was published in the Oct. 6, 2013, edition of the journal Nature.
The new class of neurons called VIP interneurons provides a secondary layer of inhibition of neuronal expression for both inhibitory neurons and minimizing the expression of neurons that cause excitation to occur in brain. The VIP interneurons release vasoactive intestinal polypeptide (VIP) and function in the auditory cortex and the medial prefrontal cortex.
The researchers verified the existence and function of VIP interneurons in mice with electronic monitoring of the neurons and the chemical released by the neurons with lasers that were keyed to the colors expressed by the neuron and chemical.
The researchers attempted to tie the VIP interneurons to specific behaviors in mice and found that both reward and punishment equally initiated the release of vasoactive intestinal polypeptide and produced a corresponding moderation of excitement and the inhibition of the production of known inhibitory chemicals.
The scientists expect that the VIP interneurons act as moderators to any extreme of behavior in mammals including humans. The researchers also indicate the potential for a learning function produced by VIP interneurons that may be tied to experience.