Abstract:

In the brain, some important visual features such as orientation, motion or binocular disparity, are processed in a region called primary visual cortex. After damages to the primary visual cortex, a curious phenomenon might happen: the patient loses his visual awareness but remains able to detect some visual events, for instance a moving object or the position of a flash of light, even without being conscious of them. This phenomenon is called blindsight. Several interesting mechanisms have been suggested to explain it, but scientists still have a lot to understand on the question. One possible way to investigate those mechanisms is to induce blindsight on healthy subjects with the use of transcranial magnetic stimulation (TMS). A lot of exciting studies on blindsight have been performed; however, some experiments have the drawback of being difficult and time demanding to set up, which is uncomfortable for the subject. In this study, we tested whether it was possible to replace a physical environment by a virtual reality one. We tried to reproduce in virtual reality an experiment of fast reaching movements under TMS-induced blindsight, done by Christensen et al. (2008) and observed if the results were similar. Unfortunately it appeared that no blindsight behaviour was induced in our experiment; hence the current outcome of our hypothesis is that virtual reality does not seem adapted to replace physical setups for acute visually guided tasks. Nevertheless, additional trials would be required to draw a more accurate conclusion, and our results do not exclude the use of virtual reality for different blindsight purposes.

Keywords: Blindsight, TMS, Virtual Reality, reaching correction.