内隐序列学习与中央执行功能的关系

The Relationship between Implicit Sequence Learning and Central Executive Function

内隐序列学习与一般认知的关系一直处于争议之中。近年来,越来越多的研究显示内隐序列学习与工作记忆(尤其是中央执行功能)存在显著关联。基于此,本研究通过两个实验来探测两者的相关及机制。实验1从行为与脑电两个角度探讨经典位置序列学习与中央执行功能的相关,发现经典位置序列学习的内隐习得量与中央执行功能的抑制、刷新功能的强度呈负相关,与转换功能没有显著相关,脑电结果也支持了这一结论。实验2在内隐序列学习中加入认知冲突来增加中央执行功能的负荷。结果发现在高抑制功能负荷任务条件下,内隐习得量与抑制功能强度的相关性发生了反转,进一步证明内隐序列学习与中央执行功能的抑制子成分在脑功能上的关系:不同条件下呈现竞争、协作等不同状态。

More and more studies in recent years showed the correlations between implicit learning, intelligence and general cognitive abilities, which reflected the individual differences in implicit learning ability. And the relationship between Working Memory(WM) and implicit sequence learning could help explore the nature of implicit sequence learning. Most early studies suggested no correlation between working memory and implicit sequence learning. However, recent studies demonstrated that working memory span and central executive function were both related to implicit sequence learning. Researchers testing Visuo-Spatial Working Memory(VSWM) revealed that working memory span related to implicit sequence learning significantly. Furthermore, studies on the relationship between central executive function and implicit learning showed that there was negative relationship between central executive function and implicit sequence learning. In order to explore relationship between working memory(especially central executive function) and implicit sequence learning, it is necessary to divide central executive function into inhibition, memory updating and switching.In this study, 69 undergraduate students of Soochow University participated in the research and they were chosen by random sampling to explore the correlation between implicit sequence learning and central executive function by a series of experiments with different stimuli conditions and different restraint loads. Moreover, together with the technique of Event-Related Potentials(ERPs), it analyzed the brain mechanism involved in implicit sequence learning and central executive function. Experiment 1, as a preliminary investigation into the correlation between implicit sequence learning and central executive function, adopted the currently popular and classic paradigm to research implicit learning-to test it via implicit learning of serial positions. The central executive function was measured through its three related, independent and separable ingredients of inhibition, memory updating and switching tested by the paradigms of numerical Stroop task, One-back memory updating task and numerical transfer task, respectively. In this experiment, behavior data and ERP data was collected at the same time. Experiment 2 set the implicit sequence learning environment in the inhibition load condition by using the way of putting the color word Stroop in the sequences and then used the same method to test inhibition, memory updating and switching. Thus, we explored the changed relationship between central executive function and implicit sequence learning in this situation.In experiment 1, the implicit sequence learning showed positive relationship with the reaction time of inhibition(r =.682, p <.01), negative relationship with memory updating scores(r=-.590, p<.01), and no significant relationship with reaction time of switching(r=-.32, p>.05). The longer reaction time of inhibition was, the worse was the function. Such results meant that there was negative relationship between implicit sequence learning and inhibition and memory updating function. However, there was no significant relationship between implicit sequence learning and switching. In addition, the results showed that implicit sequence learning had no significant relationship with all of inhibition, memory updating and switching in control group. The ERP data showed the same relationship. In experiment 2. The results showed the opposite relationship between implicit sequence learning and reaction time of inhibition(r =-.434, p <.05) compared with that in experiment 1. This meant that the relationship between implicit sequence learning and inhibition function turned into positive, and in that situation, implicit sequence learning had no relationship with both memory updating(r=-.247, p<.05) and switching(r=-.324, p<.05).Specifically, this research can be concluded as follows:(1) There is negative correlation between implicit sequence learning, inhibition and memory updating function, but no correlation between implicit sequence learning and switching.(2) Study finds that wave N200 of the inhibition function and wave P300 of the memory updating function have a significant negative correlation with the difference in waves N200 of implicit sequence learning, which proves the connection in the brain mechanism between implicit sequence learning and central executive function.(3) There is positive correlative relationship between implicit sequence learning and central executive function in high load inhibition. This suggests that in different situations, there are different relationships between implicit sequence learning and central executive function.