Visual Perceptual Learning

Dynamic Glass patterns (GPs) are visual stimuli used to investigate the mechanisms underlying the integration of form and motion information. There is brain imaging evidence that non-directional motion generated by dynamic GPs activates the human motion complex (hMT+) similarly to directional motion in random dot kinematograms (RDKs). However, it is still debated whether dynamic GPs and RDKs rely on the same processing mechanisms. The aim of the present study is twofold. On the one hand, we would like to psychophysically address this question by using a visual perceptual learning (VPL) paradigm. On the other hand we would like to test the causal effect of high frequency transcranial random noise stimulation (hf-tRNS) over hMT+ in VPL. Our hypotheses are the following: 1) the enhancement of the neural activity of hMT+ by applying hf- tRNS should increase visual perceptual learning; consequently we expect a more robust learning transfer between RDKs and dynamic GPs. The rationale is that generalization of VPL to the non- trained stimulus would indicate that the same mechanisms are involved in the processing of both dynamic GPs and RDKs, whereas the specificity of VPL would indicate that different mechanisms subtend the processing of the two types of stimuli. The results we expect is that learning transfer to both stimuli and that this effect is significantly increased by applying hf-tRNS over hMT+.

FUNDING: Grant from MUR (Dipartimenti di Eccellenza DM 11/05/2017 n. 262)