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Visual advantage in deaf adults linked to retinal changes.

Codina C, Pascalis O, Mody C, Toomey P, Rose J, Gummer L, Buckley D - PLoS ONE (2011)

Bottom Line: Deaf adults also showed a significantly different pattern of retinal nerve fibre layer (RNFL) distribution compared to controls.Significant correlations between the depth of the RNFL at the inferior-nasal peripapillary retina and the corresponding far temporal and superior temporal visual field areas (sensitivity) were found.Our results show that cross-modal plasticity after early onset deafness may not be limited to the sensory cortices, noting specific retinal adaptations in early onset deaf adults which are significantly correlated with peripheral vision sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Academic Unit of Ophthalmology and Orthoptics, University of Sheffield, Sheffield, United Kingdom. C.Codina@Sheffield.ac.uk

ABSTRACT
The altered sensory experience of profound early onset deafness provokes sometimes large scale neural reorganisations. In particular, auditory-visual cross-modal plasticity occurs, wherein redundant auditory cortex becomes recruited to vision. However, the effect of human deafness on neural structures involved in visual processing prior to the visual cortex has never been investigated, either in humans or animals. We investigated neural changes at the retina and optic nerve head in profoundly deaf (N = 14) and hearing (N = 15) adults using Optical Coherence Tomography (OCT), an in-vivo light interference method of quantifying retinal micro-structure. We compared retinal changes with behavioural results from the same deaf and hearing adults, measuring sensitivity in the peripheral visual field using Goldmann perimetry. Deaf adults had significantly larger neural rim areas, within the optic nerve head in comparison to hearing controls suggesting greater retinal ganglion cell number. Deaf adults also demonstrated significantly larger visual field areas (indicating greater peripheral sensitivity) than controls. Furthermore, neural rim area was significantly correlated with visual field area in both deaf and hearing adults. Deaf adults also showed a significantly different pattern of retinal nerve fibre layer (RNFL) distribution compared to controls. Significant correlations between the depth of the RNFL at the inferior-nasal peripapillary retina and the corresponding far temporal and superior temporal visual field areas (sensitivity) were found. Our results show that cross-modal plasticity after early onset deafness may not be limited to the sensory cortices, noting specific retinal adaptations in early onset deaf adults which are significantly correlated with peripheral vision sensitivity.

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Mean visual field areas for deaf and hearing participants.Bars indicate areas in degrees2 for the mid peripheral (2Ie Goldmann stimulus of luminance 20 cds/m2, area 0.25 mm2) and far peripheral (4Ie Goldmann stimulus of luminance 328 cds/m2, area 0.25 mm2) visual fields for the deaf (blue) and hearing (red) participants. Error bars denote SEM and raw data were root squared prior to statistical analysis due to the non-normative behaviour of area data.
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pone-0020417-g002: Mean visual field areas for deaf and hearing participants.Bars indicate areas in degrees2 for the mid peripheral (2Ie Goldmann stimulus of luminance 20 cds/m2, area 0.25 mm2) and far peripheral (4Ie Goldmann stimulus of luminance 328 cds/m2, area 0.25 mm2) visual fields for the deaf (blue) and hearing (red) participants. Error bars denote SEM and raw data were root squared prior to statistical analysis due to the non-normative behaviour of area data.

Mentions: It was important to test whether the increase in peripheral visual sensitivity previously documented in deaf adults was also present in the adults from this study. Of the deaf and hearing participants who participated in OCT, 8 deaf (6M, 2F, mean age 33.1 yrs) and 10 hearing (8M, 2F, mean age 30) participants underwent assessment of their visual field sensitivity using Goldmann perimetry (see experimental procedures for details). Figure 2 clearly shows that the mean visual field areas were larger for the deaf participants for both the mid-peripheral (4327.68°2 vs 2607.81.68°2) and far-peripheral fields (10384.01°2 vs 9209.1°2). A two factor ANOVA was conducted on the root squared raw data where the first factor was visual field (mid peripheral or far peripheral) and the second factor was group (deaf or hearing). As expected, the effect of visual field was significant (F1,64 = 226.7, p<0.001), and deaf showed significantly larger visual fields (F1,64 = 14.64, p<0.0001). The difference between deaf and hearing visual fields was significant for the mid-peripheral visual field (t = 3.464, p = 0.015) and for the far peripheral visual field (t = 2.346, p = 0.041).


Visual advantage in deaf adults linked to retinal changes.

Codina C, Pascalis O, Mody C, Toomey P, Rose J, Gummer L, Buckley D - PLoS ONE (2011)

Mean visual field areas for deaf and hearing participants.Bars indicate areas in degrees2 for the mid peripheral (2Ie Goldmann stimulus of luminance 20 cds/m2, area 0.25 mm2) and far peripheral (4Ie Goldmann stimulus of luminance 328 cds/m2, area 0.25 mm2) visual fields for the deaf (blue) and hearing (red) participants. Error bars denote SEM and raw data were root squared prior to statistical analysis due to the non-normative behaviour of area data.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3105994&req=5

pone-0020417-g002: Mean visual field areas for deaf and hearing participants.Bars indicate areas in degrees2 for the mid peripheral (2Ie Goldmann stimulus of luminance 20 cds/m2, area 0.25 mm2) and far peripheral (4Ie Goldmann stimulus of luminance 328 cds/m2, area 0.25 mm2) visual fields for the deaf (blue) and hearing (red) participants. Error bars denote SEM and raw data were root squared prior to statistical analysis due to the non-normative behaviour of area data.
Mentions: It was important to test whether the increase in peripheral visual sensitivity previously documented in deaf adults was also present in the adults from this study. Of the deaf and hearing participants who participated in OCT, 8 deaf (6M, 2F, mean age 33.1 yrs) and 10 hearing (8M, 2F, mean age 30) participants underwent assessment of their visual field sensitivity using Goldmann perimetry (see experimental procedures for details). Figure 2 clearly shows that the mean visual field areas were larger for the deaf participants for both the mid-peripheral (4327.68°2 vs 2607.81.68°2) and far-peripheral fields (10384.01°2 vs 9209.1°2). A two factor ANOVA was conducted on the root squared raw data where the first factor was visual field (mid peripheral or far peripheral) and the second factor was group (deaf or hearing). As expected, the effect of visual field was significant (F1,64 = 226.7, p<0.001), and deaf showed significantly larger visual fields (F1,64 = 14.64, p<0.0001). The difference between deaf and hearing visual fields was significant for the mid-peripheral visual field (t = 3.464, p = 0.015) and for the far peripheral visual field (t = 2.346, p = 0.041).

Bottom Line: Deaf adults also showed a significantly different pattern of retinal nerve fibre layer (RNFL) distribution compared to controls.Significant correlations between the depth of the RNFL at the inferior-nasal peripapillary retina and the corresponding far temporal and superior temporal visual field areas (sensitivity) were found.Our results show that cross-modal plasticity after early onset deafness may not be limited to the sensory cortices, noting specific retinal adaptations in early onset deaf adults which are significantly correlated with peripheral vision sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Academic Unit of Ophthalmology and Orthoptics, University of Sheffield, Sheffield, United Kingdom. C.Codina@Sheffield.ac.uk

ABSTRACT
The altered sensory experience of profound early onset deafness provokes sometimes large scale neural reorganisations. In particular, auditory-visual cross-modal plasticity occurs, wherein redundant auditory cortex becomes recruited to vision. However, the effect of human deafness on neural structures involved in visual processing prior to the visual cortex has never been investigated, either in humans or animals. We investigated neural changes at the retina and optic nerve head in profoundly deaf (N = 14) and hearing (N = 15) adults using Optical Coherence Tomography (OCT), an in-vivo light interference method of quantifying retinal micro-structure. We compared retinal changes with behavioural results from the same deaf and hearing adults, measuring sensitivity in the peripheral visual field using Goldmann perimetry. Deaf adults had significantly larger neural rim areas, within the optic nerve head in comparison to hearing controls suggesting greater retinal ganglion cell number. Deaf adults also demonstrated significantly larger visual field areas (indicating greater peripheral sensitivity) than controls. Furthermore, neural rim area was significantly correlated with visual field area in both deaf and hearing adults. Deaf adults also showed a significantly different pattern of retinal nerve fibre layer (RNFL) distribution compared to controls. Significant correlations between the depth of the RNFL at the inferior-nasal peripapillary retina and the corresponding far temporal and superior temporal visual field areas (sensitivity) were found. Our results show that cross-modal plasticity after early onset deafness may not be limited to the sensory cortices, noting specific retinal adaptations in early onset deaf adults which are significantly correlated with peripheral vision sensitivity.

Show MeSH
Related in: MedlinePlus