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APPLIED COGNITIVE PSYCHOLOGY Appl. Cognit. Psychol. 13: 257±268 (1999) Recall, Recognition, and Con®dence Patterns in Eyewitness Testimony MALEN MIGUELES* and ELVIRA GARCIÂA-BAJOS University of the Basque Country, San SebastiaÂn, Spain SUMMARY The diversity of methods, contents and tests used in the study of eyewitness memory may have contributed to discrepancies in results in this ®eld. In this experiment, using incidental or intentional learning, we examine the recall and recognition of actions and details concerning the central and peripheral information of a kidnapping. A similar pattern emerges in free recall, hits and recognition con®dence: scores are much higher in actions than in central details and there are almost no dierences between peripheral actions and details, showing that the distribution of attentional resources is dierent for actions and details in central than in peripheral information. Although in recall the degree of error was low, in recognition false alarms, especially those in central actions, reduced the level of accuracy to even lower than chance performance in both incidental and intentional groups, also showing that subjects accept false but plausible contents with a high level of con®dence. Copyright # 1999 John Wiley & Sons, Ltd. Although research on eyewitness testimony has attempted to determine memory accuracy and completeness in emotional events, the diversity of research methods used, the lack of uniformity in contents evaluated and the dierent tests utilized have hindered the elaboration of a coherent model. Thus, ®eld studies (Cutshall and Yuille, 1989; Yuille and Cutshall, 1986) and work on autobiographical emotional or traumatic experiences (Reisberg et al., 1988; Wagenaar and Groeneweg, 1990) indicate that subjects have vivid outstanding recall of events and good long-term retention. In contrast, others present recall impairment when there is increased violence (Kuehn, 1974), amnesia in traumatic situations (Christianson and Nilsson, 1989) and lower performance in emotional as opposed to neutral versions in laboratory work where slides or ®lms are used to simulate events (Cliord and Hollin, 1981; Cliord and Scott, 1978; Loftus and Burns, 1982). Studies in which positive emotional eects are noted mainly evaluate central aspects of events, whereas negative eects are re¯ected when assessing more particular details or, as Christianson and Loftus (1991) point out, when central and peripheral aspects are combined. It is logical, except in the case of highly traumatic events or in clinical cases, that emotional contents draw attention to the central aspects of the event, *Correspondence to: Malen Migueles, Faculty of Psychology, The University of the Basque Country, Avda Tolosa 70, 20009 San SebastiaÂn, Spain. E-mail: [email protected] Contract grant sponsor: The University of the Basque Country CCC 0888±4080/99/030257±12 $17.50 Copyright # 1999 John Wiley & Sons, Ltd. Accepted 20 March 1998 258 M. Migueles and E. GarcõÂa-Bajos leaving the more peripheral contents outside of the focus of attention, particularly if resources are limited. Therefore, the dierence between central and peripheral information set forth in the attentional narrowing hypothesis (Easterbrook, 1959) may largely explain the divergences detected. Taking this variable into account, ®eld studies (Christianson and HuÈbinette, 1993), traumatic autobiographical experiences (Christianson and Loftus, 1990; Wessel and Merckelbach, 1994), laboratory work simulating events by means of slides (Burke et al., 1992; Christianson, 1984; Christianson et al., 1996; Christianson and Loftus, 1987, 1991; Heuer and Reisberg, 1990), ®lms (Kebeck and Lohaus, 1986) or aversive situations (Wessell and Merckelbach, 1997) demonstrate that central contents of emotional events are recalled with precision to the detriment of other more peripheral contents. The distinction between central and peripheral information is pertinent, although not without complications. The main ones lies in its de®nition. Christianson (e.g. Christianson, 1992; Christianson et al., 1996) embraces a perceptual-spatial de®nition, regarding aspects linked to the emotional source as central (gist and its central details), and contents preceding or following the emotional event, or those irrelevant or spatially non-central to the emotional core, as peripheral. However, Burke, Heuer and Reisberg (1992; Heuer and Reisberg, 1990, 1992) support a conceptual de®nition, viewing aspects which cannot be excluded or changed without altering the argument of the event as central, and contents irrelevant to the argument as peripheral. An additional problem involves determining which contents should be evaluated so that performance in both types of information (central versus peripheral) is equal, since gist, facts and relevant details are not comparable to more particular details. Laboratory studies have placed emphasis on details (Heuer and Reisberg, 1992), but we cannot exclude the recall of actions, de®ned as the clearly apparent execution of verbal and non-verbal behaviours (Sanders and Chiu, 1988), since they accurately capture the argument and sequence of facts. The object of this experiment is to study recall and recognition of actions and details in both central and peripheral information. A ®lm depicting a kidnapping attempt was selected; it had a highly emotional content that captivated the viewer's attention from beginning to end. The kidnapping itself (central information), which occurs quickly and unexpectedly, appears in the central scenes; but beforehand, afterwards and simultaneously, there is a sequence of incidents that, although not directly connected with the emotional source (peripheral information), make up part of the event. In laboratory studies an attempt has been made to prevent eyewitnesses being intentional material witnesses, indicating to them, for example, that the object of the study is to examine their physiological responses (e.g. Burke et al., 1992; Christianson, 1984; Heuer and Reisberg, 1990). In this study one intentional and one incidental learning condition were prepared for the purposes of checking to see if the type of learning aects general performance or the memory pattern for the dierent contents of the event. Another relevant aspect in the area of eyewitness memory is the repetition of evaluation tests, especially in recalling or narrating the event. Repetition improves net recall (Dunning and Stern, 1992; Scrivner and Safer, 1988; Turtle and Yuille, 1994), but can also produce errors and intrusions (Eugenio et al., 1982). Therefore, it seems appropriate to ascertain whether the eects are the same for actions and details in both central and peripheral information. Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) Eyewitness testimony 259 Finally, the study of response con®dence has been restricted almost exclusively to eyewitness identi®cation. In this case, by means of a true/false recognition test, we can check to see if con®dence in testimony is determined by the type of information (central, peripheral) and contents (actions, details) evaluated, or if, on the contrary, it is determined by the four possible types of responses in recognition: Hits, False Alarms, Correct Rejections and Misses. METHOD Subjects A total of 102 psychology students from the University of the Basque Country participated in this experiment: 20 males and 82 females between the age of 21 and 26, with no previous experience in experiments. They were divided into two groups, incidental versus intentional, of 51 subjects each. Six subjects from the incidental group and two from the intentional group were eliminated as a result of improperly following instructions. Design A 2 2 2 2 (Group: Incidental versus Intentional Information: Central versus Peripheral Content: Actions versus Details Recall trials: First versus Second) mixed factorial design was used, with Group being the only between-subjects factor. Following the two recall trials, all subjects responded to the recognition test and rated their response con®dence. Material Subjects received three sequences on a Sony VPH-1000QM Super Bright video projector with a 2.5 2-m screen. First, they heard 2 minutes of news related to drugs. Afterwards, they saw an emotional ®lm sequence about a kidnapping attempt and, lastly, they saw 2 minutes of advertisements. The ®lm on the kidnapping lasted 1 minute 10 seconds, with 35 seconds of central information and another 35 seconds of peripheral information. It begins as a boat arrives at a very busy port and the passengers get o. After this peripheral information, a young woman passenger, following a struggle, is forced into a van, in spite of being helped by another young man. This central information ends when the girl manages to escape from her kidnappers in a trac jam. The ®lm ®nishes with peripheral information having to do with a man driving around the port looking for the girl. There is no dialogue in this sequence, only background music, outdoor noise and the screams that arise from the situation. Two independent judges, with experience in incident content and narrative protocol analysis, evaluated the sequences of the ®lm as central (the kidnapping itself) and peripheral (the remaining scenes). They also considered actions (directly observable behaviour or facts), determining 35 central actions (e.g. a man lifts up the tarpaulin of the van or he lunges at the girl) and 35 peripheral actions (e.g. a boat docks or the passengers get o). The details, both central and peripheral, were innumerable and were de®ned (for the purpose of putting together the recognition test Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) 260 M. Migueles and E. GarcõÂa-Bajos and scoring recall) as any descriptive aspect of the ®lm contents (i.e. places, people, vehicles, objects, and so on). The recognition test was composed of 24 sentences which followed the event in chronological order. All the sentences were used to create a coherent narration, adding the contextual information needed so that each one would make sense. Half of the sentences were false, though totally plausible in the situation, trying not to include atypical information. It included six central actions (e.g. true: The young man who tried to help the girl struggled with the kidnappers; false: Eventually the girl escapes amid the crowd) and six central details (e.g. true: The hand of one of the kidnappers was bandaged; false: One of the kidnappers had a moustache). There were also six peripheral actions (e.g. true: The man who was looking for the girl honked his horn to clear the way; false: On the dock there were some men loading drums onto a lorry) and six peripheral details (e.g. true: The name of the boat that docks at the port was called the Samaina; false: The man looking for the girl drove a white car). Furthermore, an attempt was made in each case to match the type of contents evaluated, in both actions and details, in regards to people, vehicles, etc. After each sentence the subjects used a 5-point scale to rate their response con®dence, 1 meaning no certainty and 5 meaning absolute certainty. Procedure The subjects in the incidental group were called to carry out an experiment on time perception. After broadly outlining some of the results obtained in classical experiments conducted in this area, they were told that their job was to judge the duration of each of the three sequences they were about to see, based on a 15-second pattern (the duration of which was not known to the subjects), presented by the experimenter using a chronometer. Following each sequence, they wrote down on a piece of paper how long it lasted according to the pattern they were given. The subjects in the intentional group, who attended the session to carry out an experiment on memory, were told to pay close attention, as they would later be evaluated. After seeing the video sequences, both groups were asked to write down the content of the ®lm in as much detail as possible. When this task was ®nished, both groups were given another 5 minutes to repeat the recall account. Finally, all subjects responded to the recognition test by indicating whether each of the sentences was true or false, as well as scoring their response con®dence. RESULTS Recall Recall was scored by assigning 1 point for each speci®c unique item of information (central actions, peripheral actions, central details or peripheral details), whether it was correct or not. For example, the statement `one of the kidnappers was wearing a black leather jacket' contains three central details, and the sentence `he stopped the car, ran to the square and looked for the girl' has three peripheral actions. Recall was corrected by two judges and the limited discrepancies were cleared up by a third independent judge. Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) Eyewitness testimony Table 1. 261 Mean number of correctly recalled units Recall Actions Central Details Actions Peripheral Details Incidental First Second 7.62 8.84 1.04 2.04 4.84 5.13 3.31 7.62 Intentional First Second 10.75 12.02 1.84 3.02 6.37 6.75 5.41 8.98 The subjects' correct answers and errors were analysed using two 2 2 2 2 (Group Information Content Recall trials) ANOVAs. Correct recall The results are presented in Table 1. The intentional group (M 27.57) recalled more units of the event than did the incidental group (M 20.22), F(1,92) 34.66, p 5 0.0001, and more actions (M 15.58) than details (M 8.32) were recalled, F(1,92) 185.48, p 5 0.0001. Although the information factor was not signi®cant (central, M 11.79; peripheral, M 12.10), the Information Content, F(1,92) 381.71, p 5 0.0001, and Group Information Content, F(1,92) 7.99, p 0.0058, interactions were signi®cant. In both groups the same pattern of results emerges. Subjects produced many central actions and few central details, whereas with average output there were scarcely dierences between the recall of peripheral actions and details. Moreover, the disparity between the recall of central actions and details was intensi®ed in the intentional group. As a result of this bias in reporting central actions at the expense of central details, more central than peripheral actions, and more peripheral than central details were recalled (p 5 0.0001). In the second trial the subjects recalled more units (M 27.20) than in the ®rst (M 20.59), F(1,92) 176.32, p 5 0.0001, and the Information Trials, F(1,92) 15, p 0.0002, Content Trials, F(1,92) 33.47, p 5 0.0001, and Information Content Trials, F(1,92) 55.73, p 5 0.0001, interactions were also signi®cant. The reason for all of these eects stems from the important increase in the recall of peripheral details, which, in the second trial, was even greater than the recall of peripheral actions. Errors There were very few errors (M 0.92); 33% of the subjects in the intentional group and 40% in the incidental group had none. More errors were made in central information (M 0.60) than in peripheral information (M 0.32), F(1,92) 14.77, p 0.0002, in details (M 0.80) than in actions (M 0.12), F(1,92) 51.19, p 5 0.0001, and in the second recall trial (M 1.15) than in the ®rst one (M 0.69), F(1,92) 23.23, p 5 0.0001. The Group Content, F(1,92) 4.95, p 0.028, and Content Trials, F(1,92) 16.29, p 0.0001, interactions were also signi®cant. The low rate of error in actions was maintained in groups as well as in recall trials, while errors in details increased from the ®rst (M 0.59) to the second trial(M 0.99), and the intentional group (M 0.95) had more errors than the Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) 262 Table 2. M. Migueles and E. GarcõÂa-Bajos Mean hit rates, false alarm rates, and A0 scores in the recognition task Actions Central Details Peripheral Actions Details Hits Incidental Intentional 0.73 0.78 0.44 0.39 0.58 0.65 0.55 0.50 FAs Incidental Intentional 0.85 0.86 0.46 0.46 0.40 0.37 0.53 0.49 A0 s Incidental Intentional 0.14 0.18 0.31 0.29 0.48 0.60 0.36 0.23 incidental group (M 0.63). Almost 50% of the errors in details were related to the colour of vehicles, clothing and hair. Recognition Hit rates, false alarm rates and A0 scores (see Table 2) were analysed by means of three 2 2 2 (Group Information Content) ANOVAs. A0 is a non-parametric analog to d 0 and is used when d0 cannot be computed because some subjects may produce hit rates of 1, false alarm rates of 0, both, or the contrary (see the formulas in Snodgrass et al., 1985). With A0 scores, 0.50 represents chance performance, and higher scores re¯ect increased sensitivity and accuracy. Hit rates The proportion of hits was higher for actions (M 0.69) than for details (M 0.47), F(1,92) 71.10, p 5 0.0001. There were two interactions: Group Content, F(1,92) 4.68, p 0.033, because the intentional group recognized more actions and fewer details than did the incidental group; and Information Content, F(1,92) 18.95, p 5 0.0001, due to the fact that, following the same pattern of recall results, in central information there were more hits for actions and fewer for detail than in peripheral information. False alarm rates There was a greater proportion of false alarms in central information (M 0.66) than in peripheral information (M 0.45), F(1,92) 51.79, p 5 0.0001, and in actions (M 0.62) than in details (M 0.48), F(1,92) 30.22, p 5 0.0001. The Information Content interaction was also signi®cant, F(1,92) 117.51, p 5 0.00001, with the proportion of false alarms in central actions being much higher than in central details or either sort of peripheral content. A0 scores Due to the high proportion of false alarms in central actions, accuracy was greater in peripheral information (M 0.42) than in central information (M 0.23), F(1,92) 21.24, p 5 0.00001. There were also two interactions: Group Content, F(1,92) 6.42, p 0.013, because the intentional group was more accurate in actions Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) Eyewitness testimony 263 and less in details than was the incidental group; and Information Content, F(1,92) 29.71, p 5 0.00001, re¯ecting equal accuracy in central and peripheral details, with greater accuracy in peripheral actions and less in central actions. Con®dence To begin, con®dence results were analysed following the comparisons generally used in eyewitness memory research. In this way, the subjects placed greater con®dence on correct answers (M 2.57) than on incorrect ones (M 2.36), F(1,92) 15.98, p 5 0.001; and `yes' answers (M 2.91) were given greater con®dence scores than were `no' answers (M 2.01), F(1,92) 147.36, p 5 0.001. In an actual crime we would only have been able to carry out the second comparison, as it would have been impossible to verify the accuracy of the answers. However, simulating an event allows us to determine the nature of the responses: Hits, FAs, CRs and Misses, and to analyse con®dence by using the type of responses as a classifying variable. Average con®dence scores are shown in Table 3. As can be seen, not all subjects gave responses in all of the categories; this is re¯ected in the degree of freedom of the variance analyses. Con®dence was higher in the intentional group (M 2.72) than in the incidental group (M 2.36), F(1,92) 10.34, p 0.0018, in central information (M 3.06) than in peripheral information (M 2.03), F(1,92) 243.38, p 5 0.001, and in actions (M 2.82) than in details (M 2.28), F(1,92) 103.6, p 5 0.001. The Information Content interaction was signi®cant, F(1,92) 72.6, p 5 0.001; subjects gave the same con®dence scores for peripheral actions as they did for details (M 2.05 and 2.01 respectively), but gave higher con®dence scores for central actions (M 3.58) than for central details (M 2.55), with the response pattern being similar to that of recall and hits. The Group Information Content interaction was also signi®cant, F(1,92) 4.5, p 0.036. The intentional group had a slightly higher con®dence rating in central actions and peripheral details than did the incidental group. In the same way, the response factor was signi®cant, F(3,270) 71.42, p 5 0.001. Con®dence was higher in hits (M 3.02) than in false alarms (M 2.83), correct rejections (M 2.15) and misses (M 1.89); it was higher in false alarms than in Table 3. Con®dence means (range 1±5) and number of subjects (in parentheses) in the recognition task Central Details Peripheral Actions Details Responses Actions Incidental Hits FAs CRs Misses 3.45 3.83 3.16 2.38 (45) (45) (16) (30) 3.30 2.56 2.1 1.72 (42) (36) (41) (42) 2.19 2.01 2.15 1.45 (39) (35) (43) (35) 2.01 1.97 1.43 1.62 (41) (43) (41) (34) Intentional Hits FAs CRs Misses 4.19 4.10 3.26 2.53 (49) (49) (15) (27) 3.73 2.85 2.29 2.06 (42) (41) (44) (47) 2.29 2.32 2.17 1.66 (46) (36) (46) (37) 2.60 2.25 2.08 2.04 (42) (42) (41) (43) Note: Incidental, n 45; Intentional, n 49. Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) 264 M. Migueles and E. GarcõÂa-Bajos correct rejections and misses; and higher in correct rejections than in misses. Type of response interacted with information, F(3,237) 21.98, p 5 0.001. In the CRs and misses (`no' answers) con®dence in the central information was only slightly higher than in peripheral information (M 0.27 and 0.28 higher respectively), but in the hits and FAs (`yes' answers) it was much greater (M 1.34 and 1.23 higher respectively). The type of response also interacted with the content, F(3,222) 7.72, p 5 0.001. In hits, CRs and misses, con®dence in actions was only slightly higher than it was in details (M 0.20, 0.40 and 0.10 higher respectively) but in the FAs it increased to a greater extent (M 0.86 higher), reaching an even higher level than with hits. DISCUSSION Several aspects set this study apart from others that analyse the dierence between the central and peripheral information in an emotional event. First, in spite of great eorts made for subjects to be incidental observers of the emotional material (e.g. Burke et al., 1992; Christianson, 1984; Heuer and Reisberg, 1990), there was nothing which contrasted in a direct and simple fashion the dierences between incidental and intentional processing. Second, by using a ®lm instead of static materials, such as slides, the dierence between the type of information (central and peripheral) and evaluated contents (actions and details) was systematically distinguished, thereby analysing the eect of both variables in two successive recall tests, recognition and response con®dence. Subjects recalled the same amount of central information (related to the emotional source) as they did peripheral information (spatially and temporally separated from the emotional source), showing that the same amount of resources were present during dierent moments of the event. But attention was directed to dierent contents, thus revealing a clear recall pattern. Whereas in peripheral information there is a balance between the recall of actions and details, central information is represented basically by actions to the detriment of more particular details, a pattern which is even more marked in the intentional group. One might think that the subjects reconstructed the event by recalling typical actions of the kidnapping script, which would generate errors; however, as in previous studies (Geiselman et al., 1985; Sanders and Chiu, 1988; Yuille and Cutshall, 1986), there were very few errors in central actions. Would the initial disadvantage in central details be diminished if subjects were given the opportunity to repeat and complete the recall account? With short intervals between trials, recall improves (Wheeler and Roediger, 1992) and narrations become longer (Dunning and Stern, 1992; Scrivner and Safer, 1988), but in this study recall did not increase equally for all contents, improving only slightly in regard to central details. The ®rst recall revolved around actions and in the second trial subjects repeated the narration, ®lling it in mainly with peripheral details. As in the work of Eugenio et al. (1982), errors increased somewhat, basically aecting details, and, more so in central than in peripheral information. Moreover, the level of attention paid to the event did not seem to be responsible for the eect, as the intentional group had more errors in details than did the incidental group. Free recall tasks tend to render accurate statements (e.g. Loftus, 1979; Lipton 1977). Thus, in this study subjects showed good recall of the event, with inaccuracies only having to do with particular details, much the same as in previous studies Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) Eyewitness testimony 265 (Christianson and HuÈbinette, 1993; Yuille and Cutshall, 1986). However, is subjects' recall a good control index of an event? The recognition test tried to determine this aspect. If we focus on hits, the recall pattern reappears showing a greater proportion of correct answers in central actions than in central details and with a balance in the peripheral information. But the analysis of false alarms and of A's oers a very dierent perspective. The subjects erroneously accepted 85% of the false central actions and between 40±50% of the rest of the contents, placing overall accuracy for the A0 scores below chance performance. Why do subjects accept false information with such high probability, especially in central actions? The false recognition sentences, unlike in other studies where distracters are easier to distinguish (e.g. Burke et al., 1992; Heuer and Reisberg, 1990), included contents that ®t in well with the event and, as in studies analysing the misinformation eect (e.g. Loftus and Homan, 1989; Weingardt et al., 1994), subjects could have been misled by suggested information. It is also possible that the subjects based their answers, in part, on the kidnapping script, fundamentally organised around actions (see Holst and Pezdek, 1992), and that particular details and more peripheral contents were not as directly speci®ed in the script. The typicality of the distracters might explain the surprising high rate of false alarms found in central actions. In an experiment carried out in our laboratory (Migueles and GarcõÂ aBajos, 1996), based on script information established in a previous normative data study, a brief narrative account of a mock mugging event was elaborated. Systematically, manipulating the typicality of the sentences in a true/false recognition test, the subjects falsely recognized almost half of the typical sentences not presented in the narration with a high degree of con®dence, as is the case in the present study, but scarcely made errors in low-typicality sentences. The practical implications of these consistent results are evident. How is recall, recognition and con®dence aected by the manipulation of intentionality? Intentional processing does not introduce major changes in regard to incidental learning; it merely intensi®es or accentuates the eects. Thus, the group content interactions showed that the intentional group recalled and recognised the actions in the ®lm with greater precision and con®dence, but as far as details were concerned it did worse than the incidental group. Furthermore, intentionality did not change the marked tendency to accept false information coherent to the situation. Con®dence results depended on the type and content of the information as much as on the nature of the response. For contents, a similar pattern to that of recall emerged once again: equal con®dence in peripheral actions and details, and greater con®dence in central actions than in central details. Therefore, con®dence values also ®t in quite well with the idea of a dierential distribution pattern of attention for the diverse contents of the event. In regard to the type of response, it might seem that con®dence predicts accuracy, since the subjects gave greater con®dence scores to their correct responses (Hits, CRs) than to their incorrect ones (FAs, Misses), but a high score in con®dence does not imply that the response is correct (e.g. the FAs). Moreover, as in studies carried out by Malpass and Devine (1981) on eyewitness identi®cation, subjects placed more con®dence on their `yes' answers (Hits and FAs) than they did on their `no' answers (CRs and Misses), regardless of accuracy, rearming the direction of their decision with their con®dence scores. In any case, the fact that con®dence was greater in Hits than it was in Misses might indicate that the subjects had a certain amount of command of the information seen in the ®lm of the Copyright # 1999 John Wiley & Sons, Ltd. Appl. Cognit. Psychol. 13: 257±268 (1999) 266 M. Migueles and E. GarcõÂa-Bajos kidnapping, but did not distinguish the false information, since the FAs received greater con®dence scores than did the CRs. To sum up, when the material allows for precise distinction between the actions and details of an emotional event, it is noted that eyewitness' attention is drawn to central actions to the detriment of descriptive details, while as for information not connected to the emotional focal point, as may be the case of more neutral events, attention is distributed more homogeneously between peripheral actions and details. As a consequence, more central actions are recalled and recognized than peripheral ones, but also more peripheral details than central. This latter aspect could be interpreted as contradictory to the results from previous studies. However, the discrepancies that strike us at ®rst are only apparent due to the fact that in many cases contents have been mixed, and in others the materials are so simple (e.g. slides) that the divergence in results merely expresses how our cognitive system operates in each situation. 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