RT Journal Article SR Electronic T1 Corticofugal Control of Vibrissa-Sensitive Neurons in the Interpolaris Nucleus of the Trigeminal Complex JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 1832 OP 1838 DO 10.1523/JNEUROSCI.4274-09.2010 VO 30 IS 5 A1 Furuta, Takahiro A1 Urbain, Nadia A1 Kaneko, Takeshi A1 Deschênes, Martin YR 2010 UL http://www.jneurosci.org/content/30/5/1832.abstract AB Trigeminal sensory nuclei that give rise to ascending pathways of vibrissal information are heavily linked by intersubnuclear connections. This is the case, for instance, of the principal trigeminal nucleus, which receives strong inhibitory input from the caudal sector of the interpolaris subnucleus. Because this inhibitory input can gate the relay of sensory messages through the lemniscal pathway, a central issue in vibrissal physiology is how brain regions that project to the interpolaris control the activity of inhibitory cells. In the present study, we examined how corticotrigeminal neurons of the primary and second somatosensory cortical areas control the excitability of interpolaris cells. Results show that these two cortical areas exert a differential control over the excitability of projection cells and intersubnuclear interneurons, and that this control also involves the recruitment of inhibitory cells in the caudalis subnucleus. These results provide a basic circuitry for a mechanism of disinhibition through which the cerebral cortex can control the relay of sensory messages in the lemniscal pathway. It is proposed that top–down control of brainstem circuits is prompted by motor strategies, expectations, and motivational states of the animal.