Tanaka Y, Sagi D
Department of Neurobiology/Brain Research, The Weizmann Institute of Science, Rehovot 76100, Israel.
Proc Natl Acad Sci U S A. 1998 Oct 13;95(21):12729-33. doi: 10.1073/pnas.95.21.12729.
Detection of a visual signal can be facilitated by simultaneous presentation of a similar subthreshold signal. Here we show that the facilitatory effect of a subthreshold signal can persist for more than 16 s. Presenting a near-threshold Gabor signal (prime) produced a phase-independent increase in contrast sensitivity (40%) to similar successive signals (target) for a period of up to 16 s. This effect was obtained only when both prime and target were presented to the same eye. We further show that the memory trace is inactivated by presenting high-contrast signals before the target. These results suggest that activated neurons in the primary visual cortex retain a near-threshold memory trace that persists until reactivated.
同时呈现一个类似的阈下信号能够促进视觉信号的检测。在此我们表明，阈下信号的促进作用能够持续超过16秒。呈现一个接近阈值的Gabor信号（启动刺激）会使对类似的连续信号（目标刺激）的对比敏感度在长达16秒的时间内产生与相位无关的增加（40%）。仅当启动刺激和目标刺激都呈现给同一只眼睛时才会获得这种效应。我们进一步表明，通过在目标刺激之前呈现高对比度信号，记忆痕迹会被灭活。这些结果表明，初级视觉皮层中被激活的神经元保留着一个接近阈值的记忆痕迹，该痕迹会持续存在直到被重新激活。
