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E u r o S c i C o n C o n f e r e n c e o n
Neurology & Neurological
Disorders
Neurology 2018
J u l y 1 2 - 1 3 , 2 0 1 8
P a r i s , F r a n c e
Page 89
Journal of Neurology and Neuroscience
ISSN: 2171-6625
M
ultisensory convergence of visual and vestibular signals has been observed within a network of cortical areas that are
involved in representing heading. Vestibular-dominant heading tuning has been found in the macaque parieto-insular
vestibular cortex (PIVC) and adjacent visual posterior sylvian area (VPS), whereas relatively balanced visual/vestibular tuning
was encountered in the ventral intraparietal (VIP) area and visual-dominant tuning was found in the dorsal medial superior
temporal (MSTd) area. Although the respective functional roles of these areas remain unclear, perceptual deficits in heading
discrimination following reversible chemical inactivation of area MSTd suggested that areas with vestibular-dominant heading
tuning also contribute to behaviour. To explore the roles of other areas in heading perception, muscimol injections were used to
reversibly inactivate either macaque PIVC or VIP bilaterally. Inactivation of anterior PIVC increased psychophysical thresholds
when heading judgments were based on either optic flow or vestibular cues, although effects were stronger for vestibular stimuli.
All behavioural deficits recovered within 36 hours. Visual deficits were larger following inactivation of the posterior portion of
PIVC, likely because these injections encroached upon VPS, which contains neurons with optic flow tuning (unlike PIVC). In stark
contrast, VIP inactivation led to no behavioural deficits, despite the fact that VIP neurons show much stronger choice-related
activity than MSTd neurons. These results suggest that area VIP either provides a parallel and partially redundant pathway for
this task, or does not participate in heading discrimination. In contrast, PIVC/VPS, along with MSTd, make causal contributions
to heading perception based on either vestibular or visual signals.
ahchen@brain.ecnu.edu.cnEvidence for a causal contribution of macaque
vestibular, but not intraparietal cortex to
heading perception
Aihua Chen
1
, Gregory C DeAngelis
2
and Dora E Angelaki
3
1
East China Normal University, Shanghai, China
2
Brain and Cognitive Sciences, University of Rochester, New York, USA
3
Baylor College of Medicine, Texas, USA
J Neurol Neurosci 2018, Volume: 9
DOI: 10.21767/2171-6625-C1-009