Department of Psychology, Sun Yat-Sen University, Guangzhou, 510275, China.
Int J Psychophysiol. 2010 Mar;75(3):234-40. doi: 10.1016/j.ijpsycho.2009.11.006. Epub 2009 Dec 4.
To investigate the influence of task difficulty on the neural mechanisms of visual perceptual learning, we recorded event-related potentials (ERPs) from human adults while they were trained with either an easy or a difficult orientation discrimination task. The discrimination thresholds of participants trained with the difficult task decreased after training, but thresholds of participants with the easy task did not. More importantly, although posterior N1 reduction and anterior P2 decrement were obtained in both conditions, only the difficult task training showed an enhancement in posterior P1, an increase in N2 and P3, and a broader scalp distribution of posterior N1 attenuation. These differences indicated that the difficult task training affected the early visual processing stage, the later ERP components, and the broader visual cortical regions, respectively. The results in the present study provide direct electrophysiological evidence for task difficulty modulation of perceptual learning-related neuroplasticity.
为了探究任务难度对视觉感知学习神经机制的影响，我们在成人被试进行简单或困难方位辨别任务训练的过程中记录了事件相关电位（ERP）。进行困难任务训练的被试的辨别阈限在训练后降低了，但进行简单任务训练的被试的辨别阈限没有变化。更重要的是，尽管在两种条件下都得到了后 N1 波幅降低和前 P2 波幅降低，但只有困难任务训练显示出了后 P1 波幅增强、N2 和 P3 波幅增加，以及后 N1 衰减的头皮分布更广。这些差异表明，困难任务训练分别影响了早期视觉加工阶段、后期 ERP 成分和更广泛的视觉皮质区域。本研究的结果为任务难度对与知觉学习相关的神经可塑性的调制提供了直接的电生理学证据。
