The Effect Of Deception On Episodic Memory And Its EEG Signature

Deception is the act of deliberately inducing others to believe untrue information.In the judicial field,criminals often cheat in the face of investigation and trial to avoid punishment;Witnesses and victims may also lie for various reasons.In daily life,deception often occurs.Previous studies using video materials or simulated criminal tasks have found that deception will lead to more damage to the cheater's memory,such as omission and false memory,than an honest response.This phenomenon is called the memory impairment effect of deception.However,there are still some deficiencies in previous studies.First,in the context of research,it mainly focuses on the memory of information related to criminal behaviour,ignoring the impact of deception on memory in daily life,and the inability of its research results is questionable.In terms of research,content mainly investigates how deception affects the memory of the event truth and deception,ignoring the impact on the memory of the cheated object.In addition,behavioural experiments are mainly used to explore this problem.If cognitive neuroscience related technologies are used to investigate the brain basis of deception affecting memory,it may expand the research in this field and provide important support for the construction and improvement of relevant theories.This study investigated the effects of deception on episodic memory,the regulatory factors of deception on memory and the EEG characteristics of deception on memory through three studies and eight experiments.In Study 1,two experiments were conducted to investigate how deception affects the situational memory of cheaters in daily shopping situations.Currently,most of the research on deception adopts the research paradigm of guiding deception,that is,randomly requiring the experimental participants to cheat or respond honestly.However,some researchers believe that this paradigm ignores the intention of deception and is not a real Deception(SIP et al.,2008).Therefore,experiment 1 of this study aims to explore the effect of active deception on memory in daily life situations.In the experiment,the experimental reward for those who cheat is higher than for those who choose to be honest,which induces the individual's active cheating behaviour.First,the active cheating group and the active honesty group are required to cheat or honestly respond to the interviewers about the shopping list items after simulating the shopping in the snack bar.Then all participants were asked to respond honestly in the final memory test,and the effect of deception on memory was discussed by comparing the memory performance of the two groups.The results showed that the active deception group had higher source and destination memory error rates and lower scores in event occurrence beliefs.This shows that the deception of active selection can also lead to memory impairment.In Experiment 2,the deception group was added to investigate the role of deception intention further.That is,the deception group was not provided with the opportunity to choose honesty or deception but was required to respond to deception.By comparing the memory performance differences of active deception,demand deception and active honesty,this paper provides data support for adopting the experimental paradigm in the follow-up experiment.The results showed no significant difference in memory performance between active deception and demand deception,and their source memory and destination memory performance were lower than that of active honesty.This shows that the memory impairment effects of active and passive deception are the same in daily life.The results of study 1 show that deception in daily life situations can also damage the cheater's memory,and the cheater's deception intention has little effect on memory.Therefore,the experiments in Study 2 and Study 3 both required the deception group to tell lies but did not provide the choice of whether to cheat or not.That is,the guided deception experiment paradigm was used to explore the memory effect of deception further.Based on study 1,study 2 investigated the regulatory factors of deception affecting memory from the aspects of deception behaviour(Experiment 1 and Experiment 2),cheater(Experiment3)and deception consequences(Experiment 4)through four experiments.Experiment 1 uses a 2(Entanglement: high/low)× 2(response: deception/honesty)between-subject experiment to investigate whether the degree of involvement could regulate the effect of deception on memory.In the experiment,the high involvement experimental participants entered the simulated snack bar to shop alone.The low involvement experimental participants imagined the shopping situation and checked the purchased goods.In the interview,the participants were randomly asked to cheat or honestly respond to the questions on their shopping list.The results showed that under the condition of high involvement,the source memory of the deception group was impaired,and the denial induced forgetting(DIF)effect appeared,which showed that the deception group had memory omissions for the items on the shopping list and also involved in the interview,indicating that the involvement adjusted the impact of deception on the source memory.In Experiment 2,a single factor between-subject design investigated the effect of deception complexity on memory.There were three experimental groups: honesty group,complex deception group and simple deception group.In the experiment,the complex deception group needs to lie to all the questions.That is,to give a negative answer to the questions about purchased goods and a positive answer to the questions about non-purchased goods.On the other hand,the simple deception group needs to cheat on purchased goods and honestly answer the questions about non purchased goods,that is,provide negative answers to all interview questions.The results showed that the complex deception group had higher error rates in both source and destination memory tests.The result showed that the complexity of deception could regulate the memory impairment effect.Experiment 3 used a 2(Group: Actor/bystander)× 2(response: honesty/deception)between-subject experiment was designed to investigate whether there were differences in the memory performance of cheaters(actors and bystanders)with different identities.In the experiment,the actor must complete the same simulated shopping task as the above experimental procedure,and the bystander must watch the whole process of the actor's shopping.Participants were then randomly asked to respond honestly or deceptively to the shopping list.The results showed that the source memory performance of the actor cheating was worse than that of the actor honest,and this effect was greater than that of the bystander cheating and the bystander honest.The result indicates that the liers did not regulate the appearance of the source memory effect of deception,but it can regulate its effect size.In addition,the results also found that deception would lead to the impairment of destination memory regardless of the liers.Finally,the results showed that the identity did not regulate the effect of deception on destination memory.Experiment 4 adopted 2(severity of deception consequences: serious / not serious)× 2(response: deception/honesty)mixed experimental design to investigate the effect of the severity of deception on memory.The experiment selected 20 life events and asked the participants to evaluate the consequences of cheating on the cheated after cheating on these events.Finally,five events with the most serious consequences and five with the least serious consequences were selected as interview questions.The results showed that whether the consequences of deception were serious or not,deception would lead to the impairment of source memory.However,the memory of the cheater and the honest person about the cheater with serious and non-serious consequences is roughly the same,which indicates that the destination memory has nothing to do with the severity of the consequences.The results show that the severity of deception does not regulate the memory impairment effect of deception.Based on this paper and previous studies,it can be found that the influence of deception on memory is mainly manifested in the damage to source memory and destination memory.Therefore,to further reveal the neural basis of deception affecting memory,study 3 used ERP technology to investigate the EEG characteristics of deception affecting source memory and destination memory.In Experiment 1,a single factor within-subject design was used.Words with the same word frequency were used as experimental materials.The participants were required to learn words first,present the learned and unlearned words to them,ask them to respond honestly or deceptively according to the clues,and then complete the task of judging the source of words.The results show that compared with an honest response,deception response time is significantly longer,the error rate is higher,and the amplitude of P3 a,N400 and LPP components induced by deception response items is larger,indicating that deception involves inhibition of real information,so it requires more cognitive resources and response is more difficult.In the1000-1200 ms time window,before the judgment of source memory,the EEG amplitude induced by deception response items was smaller than that of honest response items,indicating that individuals invested more cognitive resources in retrieving the source memory of honest response items.The process of deception needs to suppress the truth information,which may damage the source monitoring.Therefore,individuals may invest less cognitive resources to extract the source memory of deception items.In short,because individuals have better source monitoring of honest response items and sufficient processing of their sources,their evoked EEG amplitude is larger.In Experiment 2,a single factor within-subject design was used to explore the effect of deception on destination memory impairment from the perspective of the cognitive nerve.In the experiment,the participants were first presented with common sense questions and asked to answer them deceptively or honestly according to the clues.Then they were presented with common sense questions again and asked to recall the questioner corresponding to the question.The results show that compared with the honest response,the deceptive response has a longer response time and higher error rate;In the time window of 1130-1280 ms,the honest response induced a larger negative wave,and in the time window of 1600-2000 ms,the deceptive response was induced a larger positive wave.These results show that deception needs to suppress the real information,leading to greater activation of the brain's frontal lobe and greater amplitude of brain waves during deception response.Furthermore,within the time window of 1600-2000 ms,the amplitude of brain waves induced by deceptive response items is larger than that of honest response items,indicating that individuals consume more cognitive resources in the process of destination memory retrieval of deceptive response items.This may be because the truth inhibition and self-focusing effect are greater in the process of deception response,so the effect of encoding and context binding of deception response items is worse than that of honest response.Therefore,more cognitive resources must be invested in extracting deception response items.Combined with the results of this paper and previous studies,this paper constructs a theoretical model of deception affecting episodic memory.This model divides scenarios into incident scenarios and deception scenarios.The former is mainly about the memory of events/details,while the latter is mainly about the memory of deception contents and objects.Different deception methods will have different effects on event scenarios and deception scenarios.Specifically,pretend amnesia will lead to omission or false memory of events/event details,which is caused by the lack of Restatement of factual information in the process of deception;Fiction can lead to a false memory of events/event details,which is caused by the failure of the source monitoring.False denial and fiction will lead to the memory impairment of deception content,caused by inhibition and source monitoring failure respectively;Deception can lead to memory impairment of the cheater,caused by inhibition and self-focus.To sum up,this paper mainly investigated the influence of deception on memory and its related regulatory factors in daily life and explored the neural basis of deception affecting memory using ERP technology.In a word,the process of deception takes up a lot of cognitive resources,which leads to the cheater's inability to perform sufficient cognitive processing on the relevant factors of the deception situation,such as interview items and deception objects.Therefore,the memory damage effect of deception appears.Therefore,this paper expands the research on the effect of deception on memory,and the results promote an understanding of how deception affects memory and its cognitive neural mechanism.This is of great significance for constructing and perfecting the related theory of deception affecting memory.At the same time,this result also reveals the harm of deception in real life.