Visual Plasticity

Sight recovery after blindness

We studied brain reorganization in two individuals who had been blind since early childhood and whose vision was partially restored as adults in their 40’s. Using functional MRI brain scans, we found that a specific region of their visual cortex (MT+), which normally responds to visual motion, responded to both sound motion and visual motion in the sight-recovery subjects. It was previously known that the visual cortex of blind persons can take on non-visual functions (cross-modal brain plasticity). Our study tells us that this brain reorganziation didn’t occur randomly, but rather took advantage of MT+’s specialization for motion processing. It also tells us that the sound responses didn’t go away once vision was restored, but persisted together with regained visual responses even after many years.

News Coverage: Nature News, Science News, New Scientist, Caltech Press Release, Dana Foundation

Related Publications:

Bock AS, Saenz M, Tungaraza R, Boynton GM, Bridge H, Fine I (2013) Visual callosal topography in the absence of retinal input Neuroimage, 81:325-34.

Weaver KE, Richards TL, Saenz M, Petropoulos H, Fine I (2013) Neurochemical changes within human early blind occipital cortex. Neuroscience, 252, 222-233.

Saenz M, Fine I (2010) Topographic Organization of V1 Projections through the Corpus Callosum in Humans, Neuroimage, 52(4), 1124-9.

Lewis LB, Saenz M, Fine I (2010) Mechanisms of cross-modal plasticity in early blind subjects, Journal of Neurophysiology, 104(6):2995-3008.

Saenz M, Lewis LB, Huth AG, Fine I, Koch C (2008) Visual motion area MT+/V5 responds to auditory motion in human sight-recovery subjects, Journal of Neuroscience, 28(20), 5141-5148.