Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH 03755, USA.
Institute for Experimental Psychology, University of Regensburg, Regensburg 93053, Germany.
Cereb Cortex. 2018 Apr 1;28(4):1260-1271. doi: 10.1093/cercor/bhx039.
Here, we report on the long-term stability of changes in behavior and brain activity following perceptual learning of conjunctions of simple motion features. Participants were trained for 3 weeks on a visual search task involving the detection of a dot moving in a "v"-shaped target trajectory among inverted "v"-shaped distractor trajectories. The first and last training sessions were carried out during functional magnetic resonance imaging (fMRI). Learning stability was again examined behaviorally and using fMRI 3 years after the end of training. Results show that acquired behavioral improvements were remarkably stable over time and that these changes were specific to trained target and distractor trajectories. A similar pattern was observed on the neuronal level, when the representation of target and distractor stimuli was examined in early retinotopic visual cortex (V1-V3): training enhanced activity for the target relative to the surrounding distractors in the search array and this enhancement persisted after 3 years. However, exchanging target and distractor trajectories abolished both neuronal and behavioral effects, suggesting that training-induced changes in stimulus representation are specific to trained stimulus identities.
在这里，我们报告了在对简单运动特征的组合进行知觉学习后，行为和大脑活动变化的长期稳定性。参与者在一项视觉搜索任务中接受了 3 周的训练，该任务涉及在倒置的“v”形干扰轨迹中检测到沿“v”形目标轨迹移动的点。第一和最后一次训练课程是在功能磁共振成像（fMRI）期间进行的。在训练结束 3 年后，我们再次通过行为和 fMRI 检查学习稳定性。结果表明，获得的行为改善随时间推移非常稳定，并且这些变化是针对训练的目标和干扰轨迹的。在早期视皮层（V1-V3）中检查目标和干扰刺激的表示时，在神经元水平上也观察到了类似的模式：与搜索数组中的周围干扰物相比，训练增强了对目标的活动，并且这种增强在 3 年后仍然存在。但是，交换目标和干扰轨迹消除了神经元和行为效应，表明刺激表示的训练诱导变化是针对训练的刺激身份的。
