Abstract: In the field of learning, strategy is usually defined as a specific conscious processing adopted by individuals. However, recent studies on implicit learning have found that strategies can be acquired unconsciously. The present study aims to investigate the using of implicit strategy in adults and its detailed genetic process evidenced in both behavioral and ERP data. Adapted from Siegler and Svetina’s study（2006）, in the present study, the experimental process was consisted of 8 sections. Algorithm problems (e.g., “27 +15”, “45 +17”, “67 +74”, “44 +52” and “33 +21”, all were in white font with a black background) were presented randomly or pseudo-randomly with a visual angle of 4.70°×1.24°. The presentation of the algorithm problems lasted 1000ms, following a fixation time of 500ms. The implicit strategy in section 1, 2, 3, 4, and 7 was set as that “if the sum of two numbers is even or larger than 100, then it is the target”. Notably, section 5 was designed to test whether the abovementioned implicit strategy had been generated from the previous 4 section training. Section 6 was set as the practice section for a new implicit strategy, while section 8 was designed to test the application of this new implicit strategy. In the 1-5 sections of the experimental process, the subjects were asked to press a key as soon as possible if the sum of the addition algorithm was greater than 90 and less than 100. In the sections 6 to 8, the subjects were asked to press a key as soon as possible if the sum of the addition algorithm was greater than 80 and less than 90. In the results, both behavioral and ERP data revealed regular changes in the subjects following repeated practice. In the behavioral data, the main effects of Section on error rate (p < .01) and response time (p < .05) were significant. Post-hoc analysis showed that both error rate and reaction time varied across experimental sections, with a significant increase in section 5 and a significant decrease in section 7. In the ERP data, a significant main effect of Section on P200 peak latency was found [F(7,112)=2.53, p< .05], with the post-hoc paired comparisons revealing a significant difference between section 4 and 5 (p< .05). Marginally significant main effects of Section on the peak to peak amplitude of P200 and N100 (p= .067) were also found. Averaged P200 and N100 peak value increased over section 1 to 4, while decreased in section 5. This pattern was contrary to the pattern of reaction time and error rate over section 1 to 5. Additionally, a significant main effect of Section (p < .01) was found on the peak latency of N400. The results support the hypotheses that implicit strategies can be generated and applied unconsciously through practice in adults. The generic process of implicit strategy can not only be revealed in the traditional behavioral data such as reaction time and error rate, but also shown in task-induced ERP components, such as P200 and N400 peak latency, P200 peak value, and N400 peak value. The results also suggest that an implicit strategy generated in a specific condition can only be partly transferred to a new condition. Similar to explicit strategies, implicit strategies are deficient in the process of utilization and transfer.

Key words: practice, implicit strategy, genetic process, application, event-related potential (ERP)

摘要： 本研究通过设置隐含算术策略的问题情境，比较不同顺序和设置条件的进程段行为反应和ERP数据差异，考察被试在不断练习条件下对隐含策略的习得过程及迁移应用特点。结果：被试在对隐含策略无意识的情况下，第1-4练习进程段的反应时、错误率显著低于第5进程段（探测段）。同时，不同进程段诱发的部分ERPs特征也呈现有规律的变化。结论：在存在隐含策略的算术策略任务情境中，通过练习人们可以在无意识情况下逐渐生成内隐策略，诱发的ERP成分P200、N400s可以部分地反映其生成过程。已生成的内隐策略，能部分地应用到相应的新情境中。

关键词: 练习, 内隐策略, 生成过程, 迁移应用, ERP