Faculté de Psychologie et des Sciences de l'Éducation, Université de Genève, Genève, Switzerland.
J Neurophysiol. 2010 Nov;104(5):2573-85. doi: 10.1152/jn.00193.2010. Epub 2010 Sep 15.
It is known that visual transients prolong saccadic latency and reduce saccadic frequency. The latter effect was attributed to subcortical structures because it occurred only 60-70 ms after stimulus onset. We examined the effects of large task-irrelevant transients on steady-state pursuit and the generation of catch-up saccades. Two screen-wide stripes of equal contrast (4, 20, or 100%) were briefly flashed at equal eccentricities (3, 6, or 12°) from the pursuit target. About 100 ms after flash onset, we observed that pursuit gain dropped by 6-12% and catch-up saccades were entirely suppressed. The relatively long latency of the inhibition suggests that it results from cortical mechanisms that may act by promoting fixation or the deployment of attention over the visual field. In addition, we show that a loud irrelevant sound is able to generate the same inhibition of saccades as visual transients, whereas it only induces a weak modulation of pursuit gain, indicating a privileged access of acoustic information to the saccadic system. Finally, irrelevant changes in motion direction orthogonal to pursuit had a smaller and later inhibitory effect.
已知视觉瞬变会延长眼跳潜伏期并降低眼跳频率。后一种效应归因于皮质下结构，因为它仅在刺激开始后 60-70 毫秒发生。我们研究了大的、与任务无关的瞬变对稳态追踪和产生追迹性眼跳的影响。两个屏幕宽的等对比度条纹（4%、20%或 100%）以相等的偏心率（3°、6°或 12°）从追踪目标短暂闪烁。在闪光开始后约 100 毫秒，我们观察到追踪增益下降了 6-12%，并且追迹性眼跳完全被抑制。这种抑制的相对较长潜伏期表明它是由皮质机制引起的，这些机制可能通过促进注视或注意力在视野中的部署来起作用。此外，我们还表明，响亮的无关声音能够产生与视觉瞬变相同的眼跳抑制，而仅引起追踪增益的微弱调制，表明听觉信息对眼跳系统具有特权访问。最后，与追踪方向垂直的运动方向的无关变化具有较小的、较晚的抑制作用。
