Neurochemical changes within human early blind occipital cortex

• Neurochemical concentrations measured in early blind and sighted individuals using 1H MRS.
• Early blindness results in reduced GABA and elevated creatine, choline and myo-Inositol.
• Early blindness modifies metabolic, GABAergic and cholinergic phospholipid pathways.
• These biochemical changes may contribute to cross-modal responses in early blind individuals.

Early blindness results in occipital cortex neurons responding to a wide range of auditory and tactile stimuli. These changes in tuning properties are accompanied by an extensive reorganization of the occipital cortex that includes alterations in anatomical structure, neurochemical and metabolic pathways. Although it has been established in animal models that neurochemical pathways are heavily affected by early visual deprivation, the effects of blindness on these pathways in humans is still not well characterized. Here, using 1H magnetic resonance spectroscopy in nine early blind and normally sighted subjects, we find that early blindness is associated with higher levels of creatine, choline and myo-Inositol and indications of lower levels of GABA within the occipital cortex. These results suggest that the cross-modal responses associated with early blindness may, at least in part, be driven by changes within occipital biochemical pathways.