Motion adaptation in area MT.
Motion adaptation in area MT.
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DOI：
10.1152/jn.00276.2002
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发表时间：
2002-12
影响因子：
2.5
通讯作者：
R. van Wezel;K. H. Britten
中科院分区：
文献类型：
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作者：
R. van Wezel;K. H. Britten
在许多感觉系统中，暴露在长时间的刺激下会引起适应，这往往会降低神经对后续刺激的反应。这种效应通常是刺激特有的，这使得适应成为信息处理的一个强有力的探索者。我们使用动态随机点运动图来测试中颞区(MT)适应效应的大小和选择性，并将它们与对人体运动辨别的影响进行比较。经S 3次适应后，MT神经元对后续测试模式的反应比适应静态模式平均降低了26%。这种反应幅度的降低在很大程度上与提出的测试刺激无关。然而，相反方向的适应改变反应的频率较低，而且非常不一致。因此，运动适应对MT内代表适应方向的神经元有系统而深远的影响，而对代表相反方向的神经元影响较小。在人类心理物理实验中，这种适应刺激会影响方向辨别，使选择偏离适应方向。如果假设运动比较步骤发生在MT之后，这种知觉变化的大小与MT区看到的变化的大小是一致的。
In many sensory systems, exposure to a prolonged stimulus causes adaptation, which tends to reduce neural responses to subsequent stimuli. Such effects are usually stimulus-specific, making adaptation a powerful probe into information processing. We used dynamic random dot kinematograms to test the magnitude and selectivity of adaptation effects in the middle temporal area (MT) and to compare them to effects on human motion discrimination. After 3 s of adaptation to a random dot pattern moving in the preferred direction, MT neuronal responses to subsequent test patterns were reduced by 26% on average compared with adaptation to a static pattern. This reduction in response magnitude was largely independent of what test stimulus was presented. However, adaptation in the opposite direction changed responses less often and very inconsistently. Therefore motion adaptation systematically and profoundly affects the neurons in MT representing the adapted direction, but much less those representing the opposite direction. In human psychophysical experiments, such adapting stimuli affected direction discrimination, biasing choices away from the adaptation direction. The magnitude of this perceptual shift was consistent with the magnitude of the changes seen in area MT, if one assumes that a motion comparison step occurs after MT.