The Effect Of Stress On The Eyewitness Memory And Judgments Of Confidence Accuracy

Judgements of confidence(JOC)refer to individuals’ subjective reports on their confidence in the results of memory retrieval.In judicial proceedings,the accuracy of eyewitnesses’ memory is often predicted by JOC,and the degree to which an individual’s JOC predicts memory accuracy is referred to as judgements of confidence accuracy.Eyewitnesses are typically under acute psychological stress during the criminal and trial processes,which can affect memory encoding and retrieval.However,previous studies have produced conflicting results due to differences in stress initiation paradigms,memory materials,and other factors.Additionally,the effect of stress on the accuracy of eyewitness confidence judgments has not been thoroughly explored,and the role of individual differences in reducing errors in high confidence judgments has been overlooked.To address these gaps in the literature,we conducted a study using emotional pictures to induce acute psychological stress and faces as memory materials to investigate the effects of stress on memory and JOC accuracy,as well as the role of ease of excitation in reducing the misidentification of high confidence witnessed events.Experiment 1 examined the effect of stress on memory and JOC accuracy,while Experiment 2 explored the effects of encoding and retrieval stress on memory and JOC accuracy.Based on the results of Experiments 1 and 2,we found that eyewitnesses’ objective memory performance was slightly lower than their subjective confidence reports,with a high rate of misidentification in high confidence events,which may be due to individual differences.Therefore,Experiment 3 added a measure of ease of excitation,which is closely related to stress and memory,to explore its role in improving the accuracy of witness confidence judgments.The study’s three experiments yielded the following conclusions:(1)Both encoding and retrieval stress can impair witness memory.Eyewitness memory performance did not differ significantly between the retrieval stress and retrieval control groups during encoding stress.However,when encoded in a non-stressed state,the memory performance of the retrieval stress group was significantly lower than that of the retrieval control group.(2)Neither encoding stress nor retrieval stress significantly affected the confidence and accuracy of eyewitnesses’ judgments.(3)When ease of excitation was included in the prediction of confidence in memory accuracy,witnesses with low excitability had higher accuracy in judging confidence than those with high excitability,regardless of stress or not.In summary,eyewitnesses in criminal proceedings are often in a state of stress,and while encoding and retrieval stress can impair their memory,they are still able to adjust their confidence judgments through metamemory monitoring,resulting in relatively accurate confidence judgments.However,high confidence identification errors are still possible under stress conditions,and counts should consider the testimony of eyewitnesses with low ease of excitation to reduce these errors.These findings shed light on the impact of stress on memory and confidence judgment accuracy and provide guidance on the admissibility of eyewitness testimony in real-world courts.