High metabolic activity in the visual cortex of early blind human subjects

Wanet-Defalque, Marie-Chantal; Veraart, Claude; Volder, Anne De; Metz, R.; Michel, Christian; Dooms, Grégoire; Goffinet, André M.

doi:10.1016/0006-8993(88)90896-7

Cited by 183 publications

(79 citation statements)

References 18 publications

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“…Thus the synaptic density of visual cortex in early-blind subjects remains higher, which results in a thicker visual cortex. This speculation is consistent with two PET studies (Wanet-Defalque et al, 1988;Veraart et al, 1990) in which the researchers showed greater cerebral blood flow and a higher rate of glucose metabolism in the visual cortex of the early blind and attributed the findings to a lack of synaptic revision during visual development.…”

Section: Discussionsupporting

confidence: 89%

Thick Visual Cortex in the Early Blind

Jiang¹,

Zhu²,

Shi³

et al. 2009

J. Neurosci.

187

158

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We investigated the key neurodevelopmental factors that determine cortical thickness, namely synaptogenesis and regression, by analyzing the thickness of the visual cortex in humans with early-and late-onset blindness. The bilateral visual cortices of the early blind were significantly thicker than those of the late blind and the sighted controls, but the latter two groups did not differ significantly. This suggests reduced "pruning" of synapses in the visual cortex, which may be due to a lack of visual experience during a critical developmental period. These findings support the hypothesis that sensory experience is necessary for an appropriate regression and remodeling of neuronal processes and that synaptic regression might be a major determinant of macroscopic anatomical features like cortical thickness.

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Section: Discussionsupporting

confidence: 89%

Thick Visual Cortex in the Early Blind

Jiang¹,

Zhu²,

Shi³

et al. 2009

J. Neurosci.

187

158

View full text Add to dashboard Cite

show abstract

“…G. Cohen et al, 1997;Hyvärinen, Carlson, & Hyvärinen, 1981;Lanzenberger et al, 2001;Pietrini et al, 2004;Ptito & Kupers, 2005;Sadato, Okada, Honda, & Yonekura, 2002;Sadato et al, 1996;Stilla, Hanna, Hu, Mariola, Deshpande, & Sathian, 2008;Uhl, Franzen, Lindinger, Lang, & Deecke, 1991;Wanet-Defalque et al, 1988;Weaver & Stevens, 2007). A number of similar neurophysiological studies have additionally found that more "visual areas" are recruited for tactile and haptic tasks in the late blind than in the congenitally blind (e.g., Büchel, Price, Frackowiak, & Friston, 1998;Goyal, Hansen, & Blakemore, 2006).…”

Section: Discussionmentioning

confidence: 98%

Blindness enhances tactile acuity and haptic 3-D shape discrimination

Norman

Bartholomew

2011

Atten Percept Psychophys

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This study compared the sensory and perceptual abilities of the blind and sighted. The 32 participants were required to perform two tasks: tactile grating orientation discrimination (to determine tactile acuity) and haptic threedimensional (3-D) shape discrimination. The results indicated that the blind outperformed their sighted counterparts (individually matched for both age and sex) on both tactile tasks. The improvements in tactile acuity that accompanied blindness occurred for all blind groups (congenital, early, and late). However, the improvements in haptic 3-D shape discrimination only occurred for the early-onset and lateonset blindness groups; the performance of the congenitally blind was no better than that of the sighted controls. The results of the present study demonstrate that blindness does lead to an enhancement of tactile abilities, but they also suggest that early visual experience may play a role in facilitating haptic 3-D shape discrimination.

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“…In patients suffering from early blindness, early visual areas, including the primary visual cortex, are responsive to tactile (Buchel et al, 1998;Cohen et al, 1999;Sadato et al, 1996) and auditory (Weeks et al, 2000) stimuli. The functional reorganization in the multisensory area observed after early visual deprivation (Rauschecker, 1995;Wanet-Defalque et al, 1988;Yaka, Yinon, & Wollberg, 1999) might be coupled to a functional strengthening of the auditory and STP connections to V1 by overtraining in the nonaffected modalities.…”

Section: Feedback Projections and Multisensory Integrationmentioning

confidence: 99%