Imperial College London
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ProfessorSimonSchultz

Faculty of Engineering, Department of Bioengineering

Professor of Neurotechnology
 
 
 
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Contact

 

s.schultz Website

 
 
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Location

 

4.11Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Seemungal:2012:cercor/bhr366,
author = {Seemungal, BM and Guzman-Lopez, J and Arshad, Q and Schultz, SR and Walsh, V and Yousif, N},
doi = {cercor/bhr366},
journal = {Cerebral Cortex},
pages = {12--19},
title = {Vestibular Activation Differentially Modulates Excitability and Response Entropy in Human V5/MT and Early Visual Cortex.},
url = {http://dx.doi.org/10.1093/cercor/bhr366},
volume = {23},
year = {2012}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Head movement imposes the additional burdens on the visual system of maintaining visual-acuity and determining the origin of retinal image motion (i.e. self-motion versus object-motion). Although maintaining visual acuity during self-motion is effected by minimising retinal slip via the brainstem vestibular-ocular reflex, higher-order visuo-vestibular mechanisms also contribute. Disambiguating self-motion versus object-motion also invokes higher-order mechanisms and a cortical visuo-vestibular reciprocal antagonism is propounded. Hence one prediction is of a vestibular modulation of visual cortical excitability and indirect measures have variously suggested none, focal or global effects of activation or suppression in human visual cortex. Using transcranial magnetic stimulation-induced phosphenes to probe cortical excitability, we observed decreased V5/MT excitability versus increased Early Visual Cortex (EVC)  excitability, during vestibular activation. In order to exclude non-specific effects (e.g. arousal) on cortical excitability, response specificity was assessed using information theory, specifically response entropy. Vestibular activation significantly modulated phosphene response entropy for V5/MT but not EVC, implying a specific vestibular effect on V5/MT responses. This is the first demonstration that vestibular activation modulates human visual cortex excitability. Furthermore, using information theory, not previously used in phosphene response analysis, we could distinguish between a specific vestibular modulation of V5/MT excitability from a non-specific effect at EVC.
AU  - Seemungal,BM
AU  - Guzman-Lopez,J
AU  - Arshad,Q
AU  - Schultz,SR
AU  - Walsh,V
AU  - Yousif,N
DO  - cercor/bhr366
EP  - 19
PY  - 2012///
SN  - 1047-3211
SP  - 12
TI  - Vestibular Activation Differentially Modulates Excitability and Response Entropy in Human V5/MT and Early Visual Cortex.
T2  - Cerebral Cortex
UR  - http://dx.doi.org/10.1093/cercor/bhr366
UR  - http://hdl.handle.net/10044/1/29334
VL  - 23
ER  -
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