Williams Ziv M, Elfar John C, Eskandar Emad N, Toth Louis J, Assad John A
Department of Neurobiology, Harvard Medical School, 220 Longwood Ave., Boston, Massachusetts 02115, USA.
Nat Neurosci. 2003 Jun;6(6):616-23. doi: 10.1038/nn1055.
We recorded from parietal neurons in monkeys (Macacca mulatta) trained to report the direction of an apparent motion stimulus consisting of regularly spaced columns of dots surrounded by an aperture. Displacing the dots by half their inter-column spacing produced vivid apparent motion that could be perceived in either the preferred or anti-preferred direction for each neuron. Many neurons in the lateral intraparietal area (LIP) responded more strongly on trials in which the animals reported perceiving the neurons' preferred direction, independent of the hand movement used to report their percept. This selectivity was less common in the medial superior temporal area (MST) and virtually absent in the middle temporal area (MT). Variations in activity of LIP and MST neurons just before motion onset were also predictive of the animals' subsequent perceived direction. These data suggest a hierarchy of representation in parietal cortex, whereby neuronal responses become more aligned with subjective perception in higher parietal areas.
我们在经过训练的猕猴（恒河猴）顶叶神经元上进行记录，这些猕猴被训练报告由被光圈包围的规则间隔点列组成的视运动刺激的方向。将点移动其列间距的一半会产生生动的视运动，每个神经元都可以在其偏好或反偏好方向上感知到。外侧顶内区（LIP）中的许多神经元在动物报告感知到神经元偏好方向的试验中反应更强，而与用于报告其感知的手部运动无关。这种选择性在内侧颞上区（MST）中不太常见，在颞中区（MT）中几乎不存在。运动开始前LIP和MST神经元活动的变化也可预测动物随后的感知方向。这些数据表明顶叶皮层中存在一种表征层次结构，即神经元反应在更高的顶叶区域与主观感知更加一致。
