Lin Zhicheng, Lu Zhong-Lin, He Sheng
Department of Psychology, The Ohio State University, 225 Psychology Building, 1835 Neil Ave., Columbus, OH, 43210, USA.
Department of Psychology, University of Minnesota, Twin Cities, MN, USA.
Atten Percept Psychophys. 2016 Oct;78(7):2185-98. doi: 10.3758/s13414-016-1101-z.
A central function of the brain is to track the dynamic statistical regularities in the environment - such as what predicts what over time. How does this statistical learning process alter sensory and attentional processes? Drawing upon animal conditioning and predictive coding, we developed a learning procedure that revealed two distinct components through which prior learning-experience controls attention. During learning, a visual search task was used in which the target randomly appeared at one of several locations but always inside an encloser of a particular color - the learned color served to direct attention to the target location. During test, the color no longer predicted the target location. When the same search task was used in the subsequent test, we found that the learned color continued to attract attention despite the behavior being counterproductive for the task and despite the presence of a completely predictive cue. However, when tested with a flanker task that had minimal location uncertainty - the target was at the fixation surrounded by a distractor - participants were better at ignoring distractors in the learned color than other colors. Evidently, previously predictive cues capture attention in the same search task but can be better suppressed in a flanker task. These results demonstrate opposing components - capture and inhibition - in experience-driven attention, with their manifestations crucially dependent on task context. We conclude that associative learning enhances context-sensitive top-down modulation while it reduces bottom-up sensory drive and facilitates suppression, supporting a learning-based predictive coding account.
大脑的一个核心功能是追踪环境中的动态统计规律,比如随着时间推移什么能预测什么。这种统计学习过程如何改变感觉和注意过程呢?借鉴动物条件作用和预测编码,我们开发了一种学习程序,该程序揭示了先前学习经验控制注意力的两个不同成分。在学习过程中,使用了一项视觉搜索任务,其中目标随机出现在几个位置之一,但总是在特定颜色的包围区域内——所学颜色用于将注意力引向目标位置。在测试过程中,颜色不再预测目标位置。当在后续测试中使用相同的搜索任务时,我们发现所学颜色继续吸引注意力,尽管这种行为对任务没有帮助,且存在一个完全具有预测性的线索。然而,当用侧翼任务进行测试时,位置不确定性最小——目标在注视点处,周围有一个干扰项——参与者在忽略所学颜色的干扰项方面比忽略其他颜色的干扰项表现更好。显然,先前具有预测性的线索在相同的搜索任务中会吸引注意力,但在侧翼任务中能得到更好的抑制。这些结果证明了经验驱动的注意力中存在相反的成分——捕获和抑制,它们的表现关键取决于任务背景。我们得出结论,联想学习增强了上下文敏感的自上而下的调节,同时减少了自下而上的感觉驱动并促进了抑制,支持基于学习的预测编码理论。