Sensory Gating to Speech and Nonspeech Stimulus and Its Relationship to Speech Perception in Noise.

Sensory gating is the cortical phenomenon that involves selective inhibition of responses to task-irrelevant stimuli. Perceiving speech in noise, a situation commonly encountered by humans, requires the irrelevant noise to be inhibited while processing the relevant speech stimulus. We hypothesized that the two (sensory gating and speech perception in noise [SPiN]) might be related and that sensory gating may provide evidence of cortical inhibition involved in SPiN. An observational research following a correlational design was conducted on 10 neurotypical individuals. Auditory sensory gating was assessed using a conditioning-testing paradigm for tone and speech token pairs. The SPiN was measured using standardized sentences in the participants' native language. Differences were observed in the gating index of the P2 peaks of speech and tone pairs. A significant relationship between SPiN and the auditory sensory gating of the P2 peak of the speech-evoked cortical potential was obtained. The results of this preliminary investigation indicate an association between the sensory gating mechanism and neurotypical individuals' ability to perceive speech in noise.