Responsiveness of single afferents in the infraorbital nerve to oral air pressures generated by consonants.

The responsiveness of receptors supplying the oral mucosa to air pressures generated during consonant production was investigated to obtain information about hypothetical mechanisms underlying speech deficits. The delay between the onset of the neural discharge and the pop puff of phonation (mouth-exist pressure) for /pa/ production was significantly shorter and less variable than it was for /ta/ and /ka/ production, suggesting that the discharge is more closely coupled to the onset of /pa/ production. The data were interpreted to imply that single fibers of the infraorbital nerve respond to the build-up of oral air pressure during /pa/ production. This, and similar sensory information, may be used by the central neural mechanisms which monitor and control the air pressures required for phonation.