Sven-Åke Christianson

Emotional stress and eyewitness memory: A critical review.

The eyewitness literature often claims that emotional stress leads to an impairment in memory and, hence, that details of unpleasant emotional events are remembered less accurately than details of neutral or everyday events. A common assumption behind this view is that a decrease in available processing capacity occurs at states of high emotional arousal, which, therefore, leads to less efficient memory processing. The research reviewed here shows that this belief is overly simplistic. Current studies demonstrate striking interactions between type of event, type of detail information, time of test, and type of retrieval information. This article also reviews the literature on memory for stressful events with respect to two major theories: the Yerkes-Dodson law and Easter-brooks cue-utilization hypothesis. To account for the findings from real-life studies and laboratory studies, this article discusses the possibility that emotional events receive some preferential processing mediated by factors related to early perceptual processing and late conceptual processing.

Remembering emotional events: The fate of detailed information

Abstract Previous research has shown that people remember details from emotional events differently than details from neutral events. However, past research suffers from inadequate equating of the details tested in the emotional and neutral events. In the current five experiments, involving a total of 397 subjects, we equated the to-be-remembered detail information. Subjects in these experiments were presented with a thematic series of slides in which the content of one critical slide in the middle of the series varied. When the critical slide was emotional (a woman injured near a bicycle), compared to neutral in nature (a woman riding a bicycle), subjects were better able to remember a central detail but less able to remember a peripheral detail. To determine whether the emotional event led to different performance simply because it was unusual, we included a third condition, in which subjects saw an “unusual” version of the event (a woman carrying a bicycle on her shoulder). Subjects in the unusual cond...

Remembering our past: Emotional events and emotions in autobiographical memories

“And the question which I have for you (Professor Anita Hill) is how reliable is your testimony in October of 1991 on events that occurred 8, 10 years ago, when you are adding new factors, explaining them by saying you have repressed a lot?,” asked Senator Specter. (Republicans and Democrats alternate in questioning, 1991). It is October 11, 1991, and the U.S. Senate Judiciary Committee is considering the controversial nomination to the Supreme Court of Judge Clarence Thomas. Toward the end of the nomination process, there is a surprise witness. An attorney, Anita Hill, who used to work for Thomas, claims he sexually harassed her a decade earlier. Hill, now a University of Oklahoma law professor, reluctantly agrees to testify in front of the Senate Judiciary Committee, and much of the nation watches spellbound as she testifies on television. “My working relationship became even more strained when Judge Thomas began to use work situations to discuss sex. … His conversations were very vivid. He spoke about acts that he had seen in pornographic films involving such matters as women having sex with animals and films showing group sex or rape scenes. … One of the oddest episodes I remember was an occasion in which Thomas was drinking a Coke in his office.

Tunnel memory for traumatic events

In four experiments subjects remembered the critical information in a traumatic slide as either more focused spatially than in its original presentation or more focused spatially than information in a matched neutral slide. Subjects comprehend a neutral scene by automatically extending its boundaries and understanding the visual information in a broader external context. However, when subjects are negatively aroused by a scene, they process more elaborately those critical details that were the source of the emotional arousal, and they maintain or restrict the scenes boundaries. ‘Tunnel memory’ results from this greater elaboration of critical details and more focused boundaries. Tunnel memory may explain the superior recognition and recall of central, emotion-arousing details in a traumatic event, as shown in previous research on emotion and memory.

Some characteristics of people’s traumatic memories

In this study, we examined whether highly emotional events are associated with persistence of memory for both central and peripheral detail, as has been claimed elsewhere in the literature (e.g., Yuille & Cutshall, 1989). A total of 437 subjects in two experiments were asked to report their “most traumatic memory” and to answer questions about their chosen memory. A major finding was a significant relationship between rated degree of emotion and the number of central details, but not peripheral details, the subjects believed that they remembered. The implication of this result for the study of emotional memory is discussed.

Remembering details of emotional events: A comparison between psychopathic and nonpsychopathic offenders

Abstract Recent research indicates that recall of the central details of a negative emotional event is better than is recall for peripheral details. We predicted that psychopaths—because of their difficulty in processing emotional information—would not show this narrowing of attention for negative events. Criminal psychopaths and nonpsychopaths, defined by the Hare Revised Psychopathy Checklist (PCL-R; Hare, 1991), were shown a series of 15 color slides. The content of the eighth (critical) slide was either emotional or neutral; in each case the critical slide contained a central detail (the color of a womans coat) and a peripheral detail (the color of a car in the background). There were no group differences in recall of the details of the neutral slide; in each case, the central and peripheral details were recalled equally well. The nonpsychopaths recalled the central detail of the emotional slide far better than they did the peripheral detail; that is, they showed the expected narrowing of attention with negative emotion. The psychopaths, on the other hand, failed to show this effect; their recall of the central and peripheral details was the same for the emotional slide as it was for the neutral slide. The results provide further support for the hypothesis that psychopaths have difficulty in processing emotional information.

Functional amnesia as induced by a psychological trauma

The present study was designed to elucidate whether factors of encoding (attention), storage (consolidation), retrieval (reconstruction), or combinations of these are responsible for amnesia due to exposure to psychologically traumatic events. Subjects in four experiments were preseated a series of slides consisting of photographs of faces, with each face accompanied by four verbal descriptors. For the control subjects, all faces were neutral. For the experimental subjects, faces in the middle of the series were horribly disfigured. Measurements of palmar and cardiac activity were made continuously during the stimulus presentation. Tests of free recall, cued recall, recognition, and cued recognition were used to measure memory performance of the verbal descriptors attached to the faces. Data from the physiological measurements and postexperimental interviews showed clearly that the emotional state wanted actually had been induced. Amnesia was found for items associated with the traumatic events. This finding was interpreted primarily in terms of encoding factors, but storage factors could not be excluded. Furthermore, anterograde amnesia was found in tests of recall but not of recognition, indicating that factors of encoding and retrieval but not of storage play a crucial role in this type of amnesia. Finally, no significant retrograde amnesia effects were obtained.

Memory and Emotional Consistency: The MS Estonia Ferry Disaster

The focus of this study is on the recall of emotional reactions and their consistency in flashbulb memories of the Estonia ferry disaster on the Baltic Sea in September of 1994. Subjects were asked for their recollections of the circumstances surrounding the news, along with ratings of emotional reactions shortly after the event and one year later. This study also explored whether recollection of emotion predicts memory quantity or consistency. Results showed that personal circumstances when receiving the news of the Estonia ferry disaster were well retained, although far from perfectly. Less than one third of the subjects could accurately recall their emotional reactions experienced upon learning about the news, but they were not more consistent in their recall of circumstantial event information as compared to the rest of the subjects.

The phenomenology of traumatic experiences in police work

Investigates situations that were perceived as stressful by Swedish police officers and the kind of support and help they had received in connection with that. A total of 162 respondents took part in the study. Results show that most of the traumatic experiences reported by police officers occurred early on in their careers. The traumatic experiences often remained in their memories in the form of visual, tactile, and olfactory sensations. A variety of stress reactions were described in connection with these experiences. As regards ways of working through the traumatic experiences, more than half reported that it helped them to talk about the event with their colleagues. Only a few had been offered debriefing or professional help in connection with the event. A notable finding is that the majority of the officers did not receive any support at all from their superiors in connection with the event.

Does simulating amnesia mediate genuine forgetting for a crime event

An experiment is reported examining memory for a crime. One group of subjects was instructed to genuinely remember the crime, and a second group was instructed to simulate amnesia for the crime. Subjects were presented a description of a crime and asked to pretend that they were the principal perpetrator. After reading the description, rating emotional reaction and involvement, and after a distraction interval, subjects were given instructions for one of two conditions: (1) Genuine--to recall everything they could; (2) Simulation--to recall so as to evade responsibility, as if they did not remember very well. A free recall test was followed by a cued recall test, and subjects were also asked to fill out a questionnaire assessing responsibility. One week later, both groups were given the same tests and asked for genuine recall and ratings. Results showed that whereas recall of the genuine group declined from test 1 to test 2, recall of the simulation group increased, but did not reach the level of the genuine group. It is suggested that in simulated amnesia cases, suspects may withhold reporting details that have a probative value for the police investigation, and that withholding of information may reduce subsequent recall of the original memory representation of the crime event. Copyright