P 29. BDNF val66met polymorphism influences the time course of changes in corticospinal excitability induced by paired associative and transcranial direct current stimulation

It is widely appreciated that brain-derived neurotrophic factor (BDNF) is released in an activity dependent manner within the brain, and that it plays a key role in regulating synaptic plasticity and long-term potentiation (LTP). A single nucleotide polymorphism (SNP) arises at nucleotide 196 of the eponymous gene in humans. This gives rise to a valine to methionine substitution at codon 66 of the precursor protein. When assessed in animal models, the presence of this substitution is associated with impaired intracellular transport and reduced capacity for LTP.Differences between met carriers and val homozygotes have been reported in studies investigating the plasticity of human motor cortex in response to various forms of brain stimulation. Those who are homozygous for the val allele show elevations in corticospinal excitability following paired associative stimulation (PAS) () and “theta burst” repetitive transcranial magnetic stimulation (rTMS) (), that are larger than those exhibited by individuals with a met allele. In contrast, reported that met carriers show an accentuated response to transcranial direct current stimulation (tDCS). Given the clinical potential of brain stimulation techniques, there is a pressing need to establish the basis of these contrarieties, and the generality of effects attributable to BDNF genotype.In the present study, we focused on corticospinal projections to muscles of the forearm that are of particular significance in rehabilitation fo...
Source: Clinical Neurophysiology - Category: Neuroscience Authors: Tags: Society Proceedings Source Type: research