2014年11月27日 第51期心理沙龙

2014-11-27 15:07:00 0人评论 次浏览 分类:通知公告

题  目:Neural networks supporting rule learning, application, and switching (规则
        学习、运用和转换的大脑神经网络)
主讲人:刘志雅副教授
时  间:1127日(周四)下午4点到5
地  点:心理学院301会议室
 
内容简介:
We identified dynamic changes in recruitment of neural connectivity networks across three phases of a rule learning task: switching, rule learning via hypothesis testing, and rule application.  During fMRI scanning, subjects viewed pairs of stimuli that differed across four dimensions (letter, color, size, screen location), chose one stimulus, and received feedback. Subjects were informed that the correct choice was determined by a simple unidimensional rule, for example “choose the blue letter.”  Once each rule had been learned and correctly applied for 4-7 trials, subjects were cued via either negative feedback or visual cues to switch to learning a new rule. Task performance was divided into three phases: Switching (first trial after receiving the switch cue), rule learning (subsequent trials through the last error trial), and rule application (correct responding after the rule was learned). Switching was associated with a limbic intrinsic connectivity network including the ventral striatum, thalamus, and parahippocampal gyrus.  Rule learning was associated with broad fronto-parietal-striatal recruitment of regions associated with the cognitive control, dorsal attention, and salience networks.  The default mode network and somatomotor networks showed a relative increase in activity during rule application.  We further investigated the effects of switching cue on shifting.  All cues were associated with activity in the ventral striatum; externally cued shifts (via visual feature change or other visual cue) were associated with additional visual cortical activity in comparison with switching cued solely by negative feedback.