Although cross-modal plasticity as a result of sensory deprivation has been documented across a wide variety of brain areas for a wide range of tasks we still have very little idea how or why cross-modal develops as it does. It is generally supposed that, when deprived of normal input, brain areas continue to fulfill their functional role but use input from other modalities. In support of this, it has been shown that MT+, a brain region highly selective for visual motion in normally sighted individuals, responds to auditory and tactile motion after early blindness. Similarly, primary auditory and surrounding cortex (PAC+), which is sensitive to apparent movement of synthesized sounds, can be activated by visual motion in profoundly deaf subjects. However, it is not clear whether these cross-modal responses carry any behavioral relevance, or whether such responses share common architecture with normal functions. The goal of this proposed project is to address these questions using a combination of BOLD multivoxel pattern analysis and adaptation techniques within both deaf and blind individuals.
A better understanding of cross-modal plasticity has strong clinical relevance: while there have recently been practical advances in rehabilitation and skill-training after sensory loss, or cortical visual/auditory injury due to stroke or trauma, our abilit to develop better rehabilitation protocols is currently limited by our lack of scientific understandin of the cortical mechanisms that underlies this plasticity in humans. and their behavioral relevance. This work is likely to have significant clinical ramifications in that it will help in development of improved knowledge-driven rehabilitation procedures.
|Jiang, Fang; Stecker, G Christopher; Fine, Ione (2014) Auditory motion processing after early blindness. J Vis 14:4|