Multisensory Perception of Self Motion: Psychophysics and Functional Neuroanatomy.
We combined caloric vestibular stimulation with visual stimulation to analyze the interaction between the visual and vestibular sensory systems in self-motion perception. We have used these modes of stimulation to study the neural interactions during simulated self motion1. We have measured brain activity in healthy participants using the method of functional magnetic resonance imaging (fMRI). Moreover, we use the method of diffusion-weighted MRI in conjunction with probabilistic fiber tracking to analyze the anatomical connectivity between vestibular and visual cortical regions. By comparing the structural and functional connectivity of the human brain at rest (i.e., resting state), it will be shown how parts of the visual-vestibular network are interconnected. Finally, we used the method of repetitive transcranial magnetic stimulation (TMS) and functional MRI to determine the neuronal source of this inhibition in the vestibular cortex. The results of these investigations provide new insights into the multisensory integration of visual and vestibular information in self-motion perception.