The Open UniversitySkip to content
 

Altered visual processing in a rodent model of Attention-Deficit Hyperactivity Disorder

Brace, L. R.; Kraev, I.; Rostron, C. L.; Stewart, M. G.; Overton, P. G. and Dommett, E. J. (2015). Altered visual processing in a rodent model of Attention-Deficit Hyperactivity Disorder. Neuroscience, 303 pp. 364–377.

URL: http://dx.doi.org/10.1016/j.neuroscience.2015.07.0...
DOI (Digital Object Identifier) Link: https://doi.org/10.1016/j.neuroscience.2015.07.003
Google Scholar: Look up in Google Scholar

Abstract

A central component of Attention-Deficit Hyperactivity Disorder (ADHD) is increased distractibility, which is linked to the superior colliculus (SC) in a range of species, including humans. Furthermore, there is now mounting evidence of altered collicular functioning in ADHD and it is proposed that a hyper-responsive SC could mediate the main symptoms of ADHD, including distractibility. In the present study we have provided a systematic characterization of the SC in the most commonly used and well-validated animal model of ADHD, the spontaneously hypertensive rat (SHR). We examined collicular-dependent orienting behavior, local field potential (LFP) and multiunit responses to visual stimuli in the anesthetized rat and morphological measures in the SHR in comparison to the Wistar Kyoto (WKY) and Wistar (WIS). We found that SHRs remain responsive to a repeated visual stimulus for more presentations than control strains and have a longer response duration. In addition, LFP and multiunit activity within the visually responsive superficial layers of the SC showed the SHR to have a hyper-responsive SC relative to control strains, which could not be explained by altered functioning of the retinocollicular pathway. Finally, examination of collicular volume, neuron and glia densities and glia:neuron ratio revealed that the SHR had a reduced ratio relative to the WKY which could explain the increased responsiveness. In conclusion, this study demonstrates strain-specific changes in the functioning and structure of the SC in the SHR, providing convergent evidence that the SC might be dysfunctional in ADHD.

Item Type: Journal Item
Copyright Holders: 2015 IBRO
ISSN: 0306-4522
Keywords: superior colliculus; spontaneously hypertensive rat; distractibility; orienting
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Life, Health and Chemical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Interdisciplinary Research Centre: Centre for Research in Computing (CRC)
Biomedical Research Network (BRN)
Item ID: 43782
Depositing User: Michael Stewart
Date Deposited: 23 Jul 2015 10:47
Last Modified: 04 Oct 2016 11:47
URI: http://oro.open.ac.uk/id/eprint/43782
Share this page:

Altmetrics

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU