What is the function of auditory cortex without auditory input?

the accuracy of the editing procedure for the detection of GABA resonance. Moreover, further studies are needed to investigate GABA reductions in larger multiple sclerosis cohorts and to assess longitudinally the sensitivity to change of this potentially unique biomarker of neurodegeneration.aminobutyric acid levels in the parietal region of patients with Alzheimer's disease. gamma-aminobutyric acid concentration correlates with impaired performance in patients with MS. Reduced gamma-aminobutyric acid concentration is associated with physical disability in progressive multiple sclerosis. Mitochondrial dysfunction as a cause of axonal degeneration in multiple sclerosis patients. A guide to the metabolic pathways and function of metabolites observed in human brain 1H magnetic resonance spectra. cingulate gamma-aminobutyric acid and glutamate/glutamine are reduced in amnestic mild cognitive impairment and are unrelated to amyloid deposition and apolipoprotein E genotype. What is the function of auditory cortex without auditory input? This scientific commentary refers to 'Cross-modal activation of auditory regions during visuo-spatial working memory in early deafness', by Ding et al. (doi:10.1093/brain/awv165). When a sensory input is absent during development, regions of the brain usually dedicated to processing input from that modality can be engaged to process input from a replacement sense. This is referred to as cross-modal plasticity, and studying it can provide rich and unique insights into the biological versus environmental constraints that act on brain development and brain function (Merabet and Pascal-Leone, 2010). For example, numerous studies report greater activation of typically 'auditory association cortices' in the superior temporal gyrus (STG), sulcus and planum temporale, in those born profoundly deaf than in their hearing peers when processing visual or somatosensory input (e.g. Karns et al., 2012). There is also a wealth of research reporting enhanced behavioural performance on visuo-spatial tasks in deaf versus hearing participants (Bavelier et al., 2006). Although it is tempting to make the intuitive assumption that these two findings must be linked, no studies with humans have yet demonstrated a clear link between the extent of cross-modal plasticity in auditory cortices in those born deaf and enhanced performance on visuo-spatial tasks. This is the question addressed by Ding and co-workers in this issue of Brain (2015). In their study, Ding et al. asked hearing and congenitally deaf participants to perform a visuo-spatial working memory task while functional MRI data were collected. Deaf participants showed faster responses than hearing participants, although there was no group difference in task accuracy. In support of previous studies, Ding et al. …