Harold Burton|Donald G. McLaren
Visual cortex activation in late-onset, Braille naive blind individuals: An fMRI study during semantic and phonological tasks with heard words
Washington University in St. Louis|Washington University in St. Louis
visual cortex activity blind shown braille literate people raise question whether braille literacy influences crossmodal reorganization used fmri examine visual cortex activation semantic phonological tasks auditory presentation words two lateonset blind individuals lacked braille literacy multiple visual cortical regions activated braille naive individuals positive bold responses noted lower tier visuotopic eg v1 v2 vp v3 several higher tier visual areas eg v4v v8 ba 37 activity extensive crosscorrelation magnitudes greater semantic compared phonological task results braille naive individuals plausibly suggest visual deprivation alone induces visual cortex reorganization crossmodal reorganization lower tier visual areas may recruited developing skills attending selected nonvisual inputs eg braille literacy enhanced auditory skills learning might strengthen remote connections multisensory cortical areas necessity braille naive participants must attend auditory stimulation language hypothesize learning attend nonvisual inputs probably strengthens remaining active synapses following visual deprivation thereby increases crossmodal activation lower tier visual areas performing highly demanding nonvisual tasks reading braille one example