Fiori F; Candidi M; Acciarino A; David N; Aglioti SM. Institution Fiori,Francesca. Department of Psychology, Sapienza University of Rome, Rome, Italy; IRCCS, Fondazione Santa Lucia, Rome, Italy; and firstname.lastname@example.org . Candidi,Matteo. Department of Psychology, Sapienza University of Rome, Rome, Italy; IRCCS, Fondazione Santa Lucia, Rome, Italy; and. Acciarino,Adriano. Department of Psychology, Sapienza University o f Rome, Rome, Italy; IRCCS, Fondazione Santa Lucia, Rome, Italy; and. David,Nicole. Department of Neurophysiology and Pathophysiolog y, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Aglioti,Salvatore Maria. Department of Psychology, Sapienza University of Rome, Rome, Italy; IRCCS, Fondazione Santa Lucia, Rome, Italy; and.
The right temporoparietal junction plays a causal role in maintaining the internal representation of verticality.
Journal of Neurophysiology. 114(5):2983-90, 2015 Nov.
Perception of the visual vertical is strongly based on our ability to match visual inflow with vestibular, proprioceptive, tactile, and even visceral information that contributes to maintaining an intern al representation of the vertical. An important cortical region implicated in multisensory integration is the right temporoparietal junction (rTPJ), which also is involved in higher order forms of body- and space-related cognition. To test whether this region integrates body-related multisensory information necessary for establishing the subjective visual vertical, we combined a psychophysical task (the rod-and-frame test) with transient inhibition of the rTPJ via continuous theta bur st stimulation (cTBS). A Gabor patch visual detection task was used as a control visual task. cTBS of early visual cortex (V1-V3) was used to test whether early visual cortices played any role in verticality estimation. We show that inhibition of rTPJ activity selectively impairs the ability to evaluate the rod’s verticality when no contextual visual information, such as a frame surrounding the rod, is provided. Conversely, trans ient inhibition of V1-V3 selectively disrupts the ability to visually detect Gabor patch orientation. This anatomofunctional dissociation supports the idea that the rTPJ plays a causal role in integrating egocentric sensory information encoded in different reference systems (i.e., vestibular and s omatic) to maintain an internal representation of verticality.
Copyright a9; 2015 the American Physiological Society.
Journal Article. Research Support, Non-U.S. Gov’t.