DISSOCIATION OF OBJECT AND SPATIAL VISION IN HUMAN EXTRASTRIATE CORTEX - AGE-RELATED-CHANGES IN ACTIVATION OF REGIONAL CEREBRAL BLOOD-FLOW MEASURED WITH [O-15]WATER AND POSITRON EMISSION TOMOGRAPHY
DISSOCIATION OF OBJECT AND SPATIAL VISION IN HUMAN EXTRASTRIATE CORTEX - AGE-RELATED-CHANGES IN ACTIVATION OF REGIONAL CEREBRAL BLOOD-FLOW MEASURED WITH [O-15]WATER AND POSITRON EMISSION TOMOGRAPHY
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DOI：
10.1162/jocn.1992.4.1.23
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发表时间：
1992-12-01
影响因子：
3.2
通讯作者：
HERSCOVITCH, P
中科院分区：
文献类型：
--
作者：
GRADY, CL;HAXBY, JV;HERSCOVITCH, P
我们以前报道过选择性激活区域脑血流（rCBF）在枕颞叶皮层在面部匹配任务（物体视觉）和激活在上级顶叶皮层在点位置匹配任务（空间视觉）的年轻受试者。本研究的目的是确定老化对这些纹外视觉处理系统的影响。研究了11名年轻（平均年龄27 ± 4岁）和9名老年（平均年龄72 ± 7岁）男性受试者。使用Scanditronix PC 1024 - 7 B断层扫描仪和（H2O）-O-15进行正电子发射断层扫描，以测量rCBF。为了定位由视觉任务激活的大脑区域，计算来自控制任务的图像与来自面部和点位置匹配任务的图像之间的逐像素差异图像。年轻人和老年人的rCBF激活在面部匹配主要是在枕颞叶皮层，激活的上级顶叶皮层在点位置匹配。这些激活的统计学比较表明，老年受试者有更多的激活枕颞叶皮层在空间任务和更多的激活上级顶叶皮层在对象任务比年轻的受试者。这些结果表明，在老年受试者的背侧和腹侧视觉通路的功能分离较少，并可能反映了这些视觉皮层区域的处理效率与年龄相关的减少。
We previously reported selective activation of regional cerebral blood flow (rCBF) in occipitotemporal cortex during a face matching task (object vision) and activation in superior parietal cortex during a dot-location matching task (spatial vision) in young subjects. The purpose of the present study was to determine the effects of aging on these extrastriate visual processing systems. Eleven young (mean age 27 +/- 4 years) and nine old (mean age 72 +/- 7 years) male subjects were studied. Positron emission tomographic scans were performed using a Scanditronix PC1024-7B tomograph and (H2O)-O-15 to measure rCBF. To locate brain areas that were activated by the visual tasks, pixel-by-pixel difference images were computed between images from a control task and images from the face and dot-location matching tasks. Both young and old subjects showed rCBF activation during face matching primarily in occipitotemporal cortex, and activation of superior parietal cortex during dot-location matching. Statistical comparisons of these activations showed that the old subjects had more activation of occipitotemporal cortex during the spatial task and more activation of superior parietal cortex during the object task than did the young subjects. These results show less functional separation of the dorsal and ventral visual pathways in older subjects, and may reflect an age-related reduction in the processing efficiency of these visual cortical areas.