Reorganization of visual cortical maps after focal ischemic lesions
Por:
Zepeda A., Vaca L., Arias C., Sengpiel F.
Publicada:
1 ene 2003
Resumen:
Plasticity after central lesions may result in the reorganization of cortical representations of the sensory input. Visual cortex reorganization has been extensively studied after peripheral (retinal) lesions, but focal cortical lesions have received less attention. In this study, we investigated the organization of retinotopic and orientation preference maps at different time points after a focal ischemic lesion in the primary visual cortex (VI). We induced a focal photochemical lesion in V1 of kittens and assessed, through optical imaging of intrinsic signals, the functional cortical layout immediately afterwards and at 4, 13, 33, and 40 days after lesion. We analyzed histologic sections and evaluated temporal changes of functional maps. Histological analysis showed a clear lesion at all time points, which shrank over time. Imaging results showed that the retinotopic and orientation preference maps reorganize to some extent after the lesion. Near the lesion, the cortical retinotopic representation of one degree of visual space expands over time, while at the same time the area of some orientation domains also increases. These results show that different cortical representations can reorganize after a lesion process and suggest a mechanism through which filling-in of a cortical scotoma can occur in cortically damaged patients.
Filiaciones:
Zepeda A.:
Max-Planck-Institut fur Neurobiol., München-Martinsried, Germany
Depto. de Biol. Celular y Fisiologia, Instituto de Invest. Biomedicas, Universidad Nac. Autonoma de Mexico, México, DF, Mexico
Depto. de Biol. Celular y Fisiologia, Instituto de Invest. Biomedicas, Universidad Nac. Autonoma de Mexico, AP 70228, 04510-México, DF, Mexico
Vaca L.:
Departamento de Biologia Celular, Instituto de Fisiologia Celular, Univ. Nacional Autonoma de Mexico, México, DF, Mexico
Arias C.:
Depto. de Biol. Celular y Fisiologia, Instituto de Invest. Biomedicas, Universidad Nac. Autonoma de Mexico, México, DF, Mexico
Sengpiel F.:
Max-Planck-Institut fur Neurobiol., München-Martinsried, Germany
Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff, United Kingdom
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