Offen Shani, Schluppeck Denis, Heeger David J
Center for Neural Science, New York University, New York, 10003, USA.
Vision Res. 2009 Jun;49(10):1352-62. doi: 10.1016/j.visres.2007.12.022. Epub 2008 Mar 7.
We measured cortical activity with functional magnetic resonance imaging to probe the involvement of early visual cortex in visual short-term memory and visual attention. In four experimental tasks, human subjects viewed two visual stimuli separated by a variable delay period. The tasks placed differential demands on short-term memory and attention, but the stimuli were visually identical until after the delay period. Early visual cortex exhibited sustained responses throughout the delay when subjects performed attention-demanding tasks, but delay-period activity was not distinguishable from zero when subjects performed a task that required short-term memory. This dissociation reveals different computational mechanisms underlying the two processes.
我们使用功能磁共振成像测量皮质活动，以探究早期视觉皮层在视觉短期记忆和视觉注意中的参与情况。在四项实验任务中，人类受试者观看两个由可变延迟期隔开的视觉刺激。这些任务对短期记忆和注意提出了不同的要求，但刺激在延迟期之前在视觉上是相同的。当受试者执行需要注意力的任务时，早期视觉皮层在整个延迟期表现出持续的反应，但当受试者执行需要短期记忆的任务时，延迟期的活动与零无明显差异。这种分离揭示了这两个过程背后不同的计算机制。
