The Effect Of Attentional Resources On Implicit Sequence Learning:Evidence From ERP

Implicit learning is different from the imperceptibly learning process of traditional explicit learning, it is a process of automatically acquiring for object structural relations from event and environment. Implicit sequence learning is one of the main paradigms in implicit learning research. Traditional studies in effects of attentional resources on implicit sequence learning uesd to adopt the dual-task paradigm, investigate the effects of the second tasks on the first task. The current sequence learning’s brain mechanism research which using event related potentials is relatively rare.On the basis of previous studies, in order to exam the effect of attentional resource on implicit sequence learning and to make up the blank on the fields of event related potential, this study toke a single task which loaded by distraction stimulus as paradigm. This study designed and completed two of ERP experiments on the fields of implicit sequence learning.In the first experiment we manipulated the number of distraction stimulus, the attentional resources that subjects assigned to target stimulus were different in the conditions of no-distraction-stimulus, one-distracting-stimuli and two-distract ing-stimuli, so we could examine the effect of attentional resources on implicit sequence learning. In the first experiment, the reaction time results showed that, with the reduction of the attentional resources which assigned to the target stimulus (increase the number of distracting stimuli would occupy more attentional resources), the performance of implicit sequence learning would become weaker (performanced in the increase of reaction time). In the electrophysiological level, the amplitudes of ERN and P3in standard stimulus was smaller than the amplitudes of ERN and P3in the abnormal stimulus, it showed that subjects had detected the abnormal stimulu which had been preset. As the subjects did not know there was a sequence rules in the presented experiment material in the explicit level, we can infer that the detection to the abnormal stimulus was on the basis of implicit learning. In this experiments, the electrophysiological results also showed that, when the number of distracting stimuli being increased, the attentional resources that assigned to the target stimulus being reduced, the performance (performanced in the electrophysiological index that included ERN amplitude and P3amplitude) of implicit sequence learning would become weaker (in a smaller amplitude).In the second experiment we used second-order conditional sequences paradigm as same as we used in the first experiment, but this time our manipulation was the shared attribute level between distracting stimuli and target stimuli, the attentional resources that subjects assigned to target stimulus were different in the conditions of no-distraction stimulus, low share-properties distracting stimuli and high share-properties distracting stimuli, therefore we could examine the effect of attentional resources on implicit sequence learning in a different way. In the second experiment, the reaction time results showed that, with the reduction of the attentional resources which assigned to the target stimulus (increase the share-properties which compared with target stimuli would occupy more attentional resources), the performance of implicit sequence learning would become weaker (performanced in the increase of reaction time). In the electrophysiological level, with the share-properties which compared with target stimuli increased, the attentional resources that assigned to the target stimulus would be reduced, the performance of implicit sequence learning became weaker.Synthesis of the results of two experiments, the conclusion is that the presence of the distracting stimuli could influence (weaken) the implicit sequence learning, and the more the attentional resources occupied by distracting stimuli, the more influence (weaken more) it would be. The present study provided an evidence that the attentional resources do have effects on the implicit sequence learning from the electrophysiological level.