Adults who cannot understand implanted speech show temporal voice area takeover by vision

Evidence

In contrast, Rouger et al. ( 2012 ) suggested a negative impact of cross modal plasticity: they found that the right temporal voice area (TVA) was abnormally activated in CI users by a visual speech-reading task and that this activity declined over time after implantation while the activity in Broca’s area (normally activated by speech reading) increased over time after implantation. Coez et al. ( 2008 ) also used PET to study activation by voice stimuli of the TVA in CI users with poor and good speech understanding. The voice stimuli induced bilateral activation of the TVA along the superior temporal sulcus in both normal hearing listeners and CI users with good speech understanding, but not in CI users with poor understanding. This result is consistent with the proposal of Rouger et al that the TVA is ‘taken over’ by visual speech reading tasks in CI users who do not understand speech well. — Dijk, Pim van, Physiology, Psychoacoustics and…, 4275