Changes in FMRI resting state networks due to audiovisual association induced effects on visual motion perception
AdvisorKafalıgönül, Hacı Hulusi
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Associative learning, the process by which an association between two stimuli or a behavior and a stimulus is learned, is one of today's exciting and important topics of neuroscience. The in uence of multisensory associations on perceptual experience has revealed unexpected levels of sensory plasticity in the adult brain. By using an audiovisual association paradigm, we designed experiments to assess motion perception and BOLD activity under various associative learning conditions. Eleven subjects (3 males) participated in the audiovisual association training followed by resting state fMRI scans. Before and after the association training, random-dot motion with varying coherence values and static tones of distinct frequencies were presented. Subjects were required to indicate the direction of random-dot motion. During the association phase, random-dots moving up or down with 100% coherence was paired with either high or low frequency static tone. The behavioral data showed that the perception of random-dot motion with low coherence was signi cantly changed in favor of exposed audiovisual association. The analyses on resting state functional data indicated that identi- ed canonical networks (i.e., visual, auditory, sensory, motor, executive, memory, and default mode) did not di er signi cantly between pre- and post- association training, and inter-hemispheric coherence values between early stage visual motion areas were not increased. On the other hand, the connectivity strength between auditory and visual networks increased signi cantly after the acquired audiovisual association. Accordingly, these ndings suggest that even brief association training can lead to changes in connectivity between low-level sensory areas.