Document Detail


Investigating the mechanisms that may underlie the reduction in contrast sensitivity during dynamic accommodation.
MedLine Citation:
PMID:  20884530     Owner:  NLM     Status:  In-Data-Review    
Abstract/OtherAbstract:
Head and eye movements, together with ocular accommodation enable us to explore our visual environment. The stability of this environment is maintained during saccadic and vergence eye movements due to reduced contrast sensitivity to low spatial frequency information. Our recent work has revealed a new type of selective reduction of contrast sensitivity to high spatial frequency patterns during the fast phase of dynamic accommodation responses compared with steady-state accommodation. Here were report data which show a strong correlation between the effects of reduced contrast sensitivity during dynamic accommodation and velocity of accommodation responses, elicited by ramp changes in accommodative demand. The results were accounted for by a contrast gain control model of a cortical mechanism for contrast detection during dynamic ocular accommodation. Sensitivity, however, was not altered during attempted accommodation responses in the absence of crystalline-lens changes due to cycloplegia. These findings suggest that contrast sensitivity reduction during dynamic accommodation may be a consequence of cortical inhibition driven by proprioceptive-like signals originating within the ciliary muscle, rather than by corollary discharge signals elicited simultaneously with the motor command to the ciliary muscle.
Authors:
Sven Mucke; Velitchko Manahilov; Niall C Strang; Dirk Seidel; Lyle S Gray; Uma Shahani
Publication Detail:
Type:  Journal Article     Date:  2010-05-01
Journal Detail:
Title:  Journal of vision     Volume:  10     ISSN:  1534-7362     ISO Abbreviation:  J Vis     Publication Date:  2010  
Date Detail:
Created Date:  2010-10-04     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101147197     Medline TA:  J Vis     Country:  United States    
Other Details:
Languages:  eng     Pagination:  5     Citation Subset:  IM    
Affiliation:
Department of Vision Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow, UK.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Determining the accommodative response from wavefront aberrations.
Next Document:  Functional frameworks of illumination revealed by probe disk technique.