Proceedings of the Annual Meeting of the Cognitive Science Society

Cochlear implantation is a standard intervention for deafness, yet the ability of implanted patients to understandspeech varies widely. To better understand this variability, we used functional near-infrared spectroscopy to image auditorycortex activation in response to different classes of sound and compared that to behavioral measures of speech perception. Bothcontrol and implanted participants with good speech perception exhibited greater cortical activity to natural speech than tounintelligible speech. In contrast, implanted participants with poor speech perception produced pronounced cortical activationacross stimulus classes. Moreover, the ratio of cortical activation in response to normal speech relative to that of scrambledspeech directly correlated with their comprehension scores, though not with auditory threshold, age, side of implantation,or time after implantation. Because implanted adults with low speech perception scores produced indistinguishable corticalactivation across stimulus classes without preferential response to speech, we interpret this as demonstration of compensatoryprocessing effort.