BDNF Polymorphism Affecting Neural Plasticity Predicts Visuo-Motor Adaptation to Left-Right Visual Reversal

Abstract

Introduction. Recent work demonstrates that there may be specific genetic profiles that predict the capacity for neural plasticity. Polymorphisms in the BDNF gene correlate with memory capacity and synaptic plasticity (Egan et al, 2003; Kleim et al, 2006), and may predict capacity for visual-motor learning and motor map plasticity (Pearson-Fuhrhop et al, 2009). Presently, we investigate the effects of short-term adaptation to left-right visual field reversal on visuo-motor task performance with two BDNF genotypes with different propensities for neural plasticity. Methods. The first hour was used to review and sign consent forms, undergo a blood draw for genetic screening for the BDNF val⁶⁶met polymorphism, and complete a series of short questionnaires. Subjects then spent an hour performing baseline visuo-motor tasks wearing a pair of Control Goggles with a restricted field of view, but no other visual alterations. Finally, subjects spent an hour performing the visuo-motor tasks a second time, this time donning Prism Goggles with right-angle prisms that left-right mirror-reverse subjects’ field of view, which was restricted identically to the Control Goggles. The visuo-motor tasks consisted of Finger Tapping, Reaching, and Walking Maze, which were performed in pseudo-randomized order during each hour (except the Maze, which was always last due to increased nausea). Results/Conclusions. On the Finger Tapping task, which is unaffected by the left-right visual reversal, there is no difference in performance between the control and prism conditions, nor a difference between the BDNF genotypes. In contrast, performance on the Reaching and Walking Maze tasks was far worse for the left-right visually reversed condition relative to normal vision for all subjects. Subjects with the val⁶⁶met polymorphism both initially performed worse and improved more rapidly than subjects with the val⁶⁶val genotype. These results indicate that there is a differential propensity for neural plasticity between these two BDNF polymorphisms.

Meeting abstract presented at VSS 2012