Department of Psychology, University of Minnesota, Minneapolis, Minnesota 55455, USA.
J Neurosci. 2010 Nov 10;30(45):15080-4. doi: 10.1523/JNEUROSCI.5703-09.2010.
Training improves performance on most visual tasks. Such perceptual learning can modify how information is read out from, and represented in, later visual areas, but effects on early visual cortex are controversial. In particular, it remains unknown whether learning can reshape neural response properties in early visual areas independent from feedback arising in later cortical areas. Here, we tested whether learning can modify feedforward signals in early visual cortex as measured by the human electroencephalogram. Fourteen subjects were trained for >24 d to detect a diagonal grating pattern in one quadrant of the visual field. Training improved performance, reducing the contrast needed for reliable detection, and also reliably increased the amplitude of the earliest component of the visual evoked potential, the C1. Control orientations and locations showed smaller effects of training. Because the C1 arises rapidly and has a source in early visual cortex, our results suggest that learning can increase early visual area response through local receptive field changes without feedback from later areas.
训练可以提高大多数视觉任务的表现。这种知觉学习可以改变信息在后期视觉区域中的读出和表示方式，但对早期视觉皮层的影响仍存在争议。特别是，目前尚不清楚学习是否可以独立于来自后期皮质区域的反馈来重塑早期视觉区域中的神经反应特性。在这里，我们通过人类脑电图来测试学习是否可以改变早期视觉皮层中的前馈信号。14 名受试者接受了超过 24 天的训练，以检测视野一个象限中的对角线光栅图案。训练提高了性能，降低了可靠检测所需的对比度，并且还可靠地增加了视觉诱发电位的最早成分 C1 的幅度。控制方向和位置的训练效果较小。由于 C1 快速出现并且源自在早期视觉皮层中，因此我们的结果表明，学习可以通过局部感受野的变化来增加早期视觉区域的反应，而无需来自后期区域的反馈。
