The Neural Mechanism Of Changing Reward Influencing Bilingual Control

As a strong motivation,reward plays an important role in the learning process,and can enhance the individual’s cognitive control ability.Bilingual learning is an issue that many reseachers are concerned about.If reward can enhance the individual’s language control ability,then reward will play an important role in language learning education.This study will provide empirical evidence and important theoretical supplement for this conclusion.Experiment 1 combines different reward patterns with the cue language switching paradigm,witch to give high rewards（1,3,5,7 or 9 point;20% for each category）for English naming,and Chinese naming will only get a constant low reward（1 point）.The setting of this reward model led to an 80% chance of getting a higher reward in English naming trials than in Chinese naming trials,and occasionally get a very high reward（such as 9 points）.This experiment aims to explore the impact of different reward modes on language control,and whether the changing reward will improve the task performance of language switching.The results showed that the reaction times（RTs）under the changing reward condition was faster than stay reward condition,indicating that the subjects’ behavior did improve due to changing reward.In addition,in stay reward condition,repeat have more significant N2 effect than switch,but no N2 effect was observed under the changing reward condition,which indicates that reward enhanced the ability of proactive control.And similar to the N2 results,in stay reward condition,repeat have more significant LPC effect than switch,while no LPC effect was found under the changing reward condition.The results show that the changing reward can improve the proactive and reactive control of bilinguals then enhance the ability of language control.Experiment 2 followed the experiment 1’s design,except that the high reward was given in Chinese trials and the low reward was given in English trials.By reversing the reward pattern and language,we assessed whether the impact of changing reward on language control is independent of language type.The results of experiment 2 were similar to those of experiment 1.For example,in stay reward condition,repeat has more significant LPC effect than switch;but no LPC effect under changing reward,indicating that the changing reward still promoted the reactive control ability.However,there are some different results,which may indicate that the effect of reward on language control is related to language type.When the changing reward was applied to second language,the improvement on second language was stronger.This might be due to the high activation of dominant language,and the performance of dominant language is good enough.In conclusion,these findings suggest that individuals will make cost-benefit trade-offs and tend to take less cognitive control but get maximum rewards.In this study,reward expectation can improve proactive and reactive control ability,but when the changing reward is applied to dominant language,the effect of reward becomes complicated.