Abnormal functional connectivity between ipsilesional V5/MT+ and contralesional striate cortex (V1) in blindsight

被引:31
作者
Silvanto, Juha [2 ]
Walsh, Vincent [3 ,4 ]
Cowey, Alan [1 ]
机构
[1] Univ Oxford, Dept Expt Psychol, Oxford OX1 3UD, England
[2] Univ Essex, Dept Psychol, Colchester CO4 3SQ, Essex, England
[3] UCL, Inst Cognit Neurosci, London WC1N 3AR, England
[4] UCL, Dept Psychol, London WC1N 3AR, England
基金
英国惠康基金;
关键词
Transcranial magnetic stimulation; Phosphenes; Visual cortex; Lateral geniculate nucleus; Blindsight; LATERAL GENICULATE-NUCLEUS; VISUAL-CORTEX; AREA V5/MT; PERCEPTION; THALAMUS; MACAQUE; MONKEY;
D O I
10.1007/s00221-009-1712-x
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
Damage to the visual cortex can lead to changes in anatomical connectivity between the remaining areas. For example, after a unilateral lesion to striate cortex (V1), an abnormal anatomical pathway can develop between the lateral geniculate nucleus of the undamaged hemisphere and the motion area V5/MT+ in the damaged hemisphere, accompanied by a hypernormal callosal connection between the area V5/MT+ of the two hemispheres. Here we investigated, using transcranial magnetic stimulation (TMS), the functional significance of these pathways in the blindsight subject GY, in whom they were first demonstrated. We show that TMS applied over the extrastriate area V5/MT+ in GY's damaged hemisphere modulates the appearance of phosphenes induced from V1 in the normal hemisphere. In contrast, in neurologically normal control subjects, TMS applied over V5/MT+ never influenced the phosphenes induced from V1 in the other hemisphere. The findings indicate an abnormal functional connectivity between V5/MT in the damaged hemisphere and the early visual cortex in the normal hemisphere, consistent with GY's abnormal anatomical connectivity.
引用
收藏
页码:645 / 650
页数:6
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