The effects of aging on visual memory: evidence for functional reorganization of cortical networks
The effects of aging on visual memory: evidence for functional reorganization of cortical networks
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DOI：
10.1016/s0001-6918(01)00037-3
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发表时间：
2001-04-01
影响因子：
1.8
通讯作者：
Della-Maggiore, V
中科院分区：
文献类型：
--
作者：
Bennett, PJ;Sekuler, AB;Della-Maggiore, V
最近的证据表明，成熟的人脑能够在损伤后进行实质性的功能重组。大脑保留了很大的可塑性，这一事实增加了在正常衰老过程中发生皮质重组的可能性。我们通过使用正电子发射断层扫描（PET）来测量年轻和老年观察者与简单视觉属性的短期记忆相关的大脑活动来研究这个问题。采用两间隔强迫选择法测量了不同刺激间隔（ISI）下正弦波光栅的空间频率辨别阈值。通过改变ISI的持续时间和在ISI的中间呈现无关的掩蔽刺激来操纵记忆负荷，老年和年轻的观察者完成了同样的实验。然而，与良好表现相关的神经系统在两个年龄组中是不同的。研究结果支持了视觉记忆的功能网络在衰老过程中进行重组的假设。(C)出版社：Elsevier Science B.V.
Recent evidence suggests that the mature human brain is capable of substantial functional reorganization following injury. The fact that the brain retains a great deal of plasticity raises the possibility that cortical reorganization may occur during normal aging. We examined this issue by using positron emission tomography (PET) to measure the brain activity associated with short-term memory for simple visual attributes in young and old observers. A two-interval forced choice procedure was used to measure spatial frequency discrimination thresholds for sine wave gratings presented at different inter-stimulus intervals (ISI). Memory load was manipulated by varying the duration of the ISI and by presenting an irrelevant masking stimulus in the middle of the ISI, Old and young observers performed the experiment equally well. However, the neural systems correlated with good performance differed for the two age groups. The results support the hypothesis that the functional networks that underlie visual memory undergo reorganization during aging. (C) 2001 Published by Elsevier Science B.V.