摘要
Background: In patients with postgenicular lesions of the visual system, areas of residual vision (ARVs) are the main predictor of recovery induced by vision restoration therapy (VRT). In these partially defective regions, the elevated pe rceptual thresholds can be acutely reduced by attentional cueing. Objective: To examine whether directing attention to ARVs using a visuospatial cue also increa ses longterm neural plasticity and thus enhances permanent training outcome. M ethods: In a prospective, randomized clinical trial, treatment outcome was compa red in patients with postgenicular visual system lesions who received either sta ndard VRT (control group [CG]; n=10) or VRT with attentional cueing (experim en tal group [EG]; n=9). Visual field size was determined before and after a 6-m on th treatment period using Tübingen Automated Perimetry and computerbased high resolution perimetry (HRP) and in regular intervals throughout this period b y HRP and detection performance in VRT. Results: In the area of the cue, restora tion of vision was significantly greater than during VRT without cueing: cued pa tients showed a much more pronounced shift of the visual field border toward the blind area than that observed in the CG or in uncued regions of the EG. Focusin g attention at ARVs during treatment changed topographic and temporal patterns o f recovery as compared with uncued regions of the visual field. Conclusions: Use of a visuospatial cue to focus attention at areas of residual vision amplifies longterm neuronal plasticity. The authors propose that topdown signals preac tivate partially damaged areas of V1, thus linking visual and attentional neuron al networks, with the effect of permanently increasing conscious visual percepti on.
Background: In patients with postgenicular lesions of the visual system, areas of residual vision (ARVs) are the main predictor of recovery induced by vision restoration therapy (VRT). In these partially defective regions, the elevated pe rceptual thresholds can be acutely reduced by attentional cueing. Objective: To examine whether directing attention to ARVs using a visuospatial cue also increa ses longterm neural plasticity and thus enhances permanent training outcome. M ethods: In a prospective, randomized clinical trial, treatment outcome was compa red in patients with postgenicular visual system lesions who received either sta ndard VRT (control group [CG]; n=10) or VRT with attentional cueing (experim en tal group [EG]; n=9). Visual field size was determined before and after a 6-m on th treatment period using Tübingen Automated Perimetry and computerbased high resolution perimetry (HRP) and in regular intervals throughout this period b y HRP and detection performance in VRT. Results: In the area of the cue, restora tion of vision was significantly greater than during VRT without cueing: cued pa tients showed a much more pronounced shift of the visual field border toward the blind area than that observed in the CG or in uncued regions of the EG. Focusin g attention at ARVs during treatment changed topographic and temporal patterns o f recovery as compared with uncued regions of the visual field. Conclusions: Use of a visuospatial cue to focus attention at areas of residual vision amplifies longterm neuronal plasticity. The authors propose that topdown signals preac tivate partially damaged areas of V1, thus linking visual and attentional neuron al networks, with the effect of permanently increasing conscious visual percepti on.
