Work

Cortical thickening of early visual areas in early monocular enucleation

Year: 2011

Type: article

Abstract: Early monocular deprivation from amblyopia results in a cortical thinning of vision-related regions including lingual, pericalcarine, cuneus, and lateral occipital areas (Du et al., 2009). In contrast, congenitally blind individuals show cortical thickening of some vision-related and oculomotor cortices but thinning of higher-order visual areas (Park et al., 2009). We investigated cortical thickness in vision-related regions of individuals who have experienced a very different form of early visual deprivation – monocular enucleation (surgical removal of one eye). Cortical thickness was analyzed from structural MRI images by determining the distance between the pial and white matter borders. Individuals who have had one eye enucleated (n = 6) early in life were compared to binocular controls (n = 11). Monocular enucleation resulted in significant thickening of cortical regions associated with low-level visual processing (cuneus), basic visual motion perception (middle temporal gyrus), and oculomotor function (posterior cingulate gyrus). In contrast, monocular enucleation resulted in significant thinning of higher-order visual areas (parahippocampal and lateral occipital gyri). These findings are consistent with behavioural data showing intact low-level spatial vision but deficient higher-order spatial vision in these individuals. While decreased cortical thickness in higher-order visual areas is consistent with amblyopia data, increased cortical thickness in early visual and oculomotor regions is not. Instead, our results are consistent with data from the congenitally blind. The complete disruption of visual input following monocular enucleation appears to promote reorganization in lower-level visual areas but atrophy in higher-level visual areas. Together with previous research, these results suggest that deprivation from monocular enucleation and amblyopia have different effects on the visual system.

Source: Journal of Vision

DOI: 10.1167/11.11.403

Authors: K. Kelly, K. DeSimone, K. Schneider, J. Steeves

Institution: York University

Language: English

Topic: Visual perception and processing mechanisms

Subfield: Cognitive Neuroscience

Field: Neuroscience

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,850