Enhanced memory for emotional pictures: A product of increased attention to affective stimuli?

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1 EUROPEAN JOURNAL OF COGNITIVE PSYCHOLOGY 2010, 22 (8), Enhanced memory for emotional pictures: A product of increased attention to affective stimuli? Louise Humphreys, Geoffrey Underwood, and Peter Chapman University of Nottingham, Nottingham, UK The current experiment addressed the question, is enhanced memory for emotional pictures due to increased attention to affective stimuli? Participants viewed pairs of pictures (emotional-neutral or neutral-neutral) whilst their eye movements were recorded; participants had to decide which picture out of each pair they preferred. There was increased attention to positive pictures and decreased attention to negative images during picture viewing. Despite this, when a recognition test was given 1 week later, memory enhancements were found for negative pictures only. Moreover, although there was a general correlation between total inspection time and memory performance, this reliability was clear only for neutral pictures, and not for emotional images. The results suggest that memory advantages for emotional pictures can occur without increased attention to such images. Keywords: Attention; Memory; Emotion; Pictures; Preference task. It is well established that memory is enhanced for emotional events (for a review see Hamann, 2001). Such memory enhancements have been found for words (e.g., LaBar & Phelps, 1998), pictures (e.g., Ochsner, 2000), and stories (e.g., Cahill & McGaugh, 1995). However, there is still uncertainty as to what causes such memory advantages. One possible explanation is that increased attentional resources to affective stimuli produce emotional memory effects. Indeed, research has shown that emotional stimuli are more likely to attract attention over neutral information (e.g., Calvo & Lang, 2004; Nummenmaa, Hyönä, & Calvo, 2006). This paper aimed to address the question of whether enhanced emotional memory can be explained by increased attention to affective stimuli. A number of studies have shown that early attention allocation (e.g., Calvo, Nummenmaa, & Hyönä, 2007; Christianson, Loftus, Hoffman, & Loftus, 1991; Kern, Libkuman, Otani, & Holmes, 2005; Talmi, Schimmack, Paterson, Correspondence should be addressed to Louise Humphreys, WMG, University of Warwick, Coventry CV4 7AL, UK. louise.humphreys@warwick.ac.uk. # 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business DOI: /

2 1236 HUMPHREYS, UNDERWOOD, CHAPMAN & Moscovitch, 2007) is important in determining emotional memory. However, the studies carried out by Talmi et al. (2007) suggest that attentional capture by emotional stimuli might only mediate memory for positive information. Talmi et al. manipulated attention directly, which allowed them to calculate the amount of attention given to a concurrent task that was carried out whilst processing positive and negative images. In Experiment 1, the authors found that there was involuntarily capture of attention by negative and positive pictures. However, this attentional bias only increased memory for positive items, suggesting that increased early attention to negative pictures does not contribute to memory advantages for such pictures. In agreement with this finding, Experiment 2 showed that even when equivalent attention was given to negative and neutral items, memory was still enhanced for the former. These two experiments suggest that early attentional capture by emotional pictures could account for enhanced memory for positive pictures. Similarly, Kern et al. (2005, Exp. 2) found superior memory for negative pictures over positive and neutral pictures when attention was divided and when attention was not divided, suggesting that enhanced memory for negative pictures appears to be independent of early attention. Other studies have found that enhanced emotional memory is due to increased exposure to the emotional stimuli (e.g., Kensinger, Garoff-Eaton, & Schacter, 2006; Maljkovic & Martini, 2005). There is also evidence which suggests that attention does not predict emotional memory (e.g., Guy & Cahill, 1999; Harris & Pashler, 2005; Kern, Libkuman, & Otani, 2002). For example, Harris and Pashler (2005) found that memory for emotional pictures is enhanced even when selective rumination to the emotional material is prevented (Exp. 1) and when the material is being ignored altogether (Exp. 2). It is important to point out that enhanced memory for affective information could be due to the emotional arousal elicited by such stimuli, rather than due to their emotional valence (i.e., positivity or negativity). Bradley, Greenwald, Petry, and Lang (1992, Exp. 1) found that high arousal images are more likely to be remembered than low arousal images on both immediate and delayed tests. In contrast, affective valence only influenced immediate recall; delayed recall was not affected by emotional valence. This highlights the importance of arousal levels in determining memory performance. Essentially, there is still uncertainty about the link between attention to, and memory for, emotional stimuli. The question of whether enhanced memory for emotional material is due to increased attention to such material is therefore still open to debate. The current experiment was aimed at addressing this question. Attention to, and memory for, emotional pictures was examined in one single study which allowed them to be directly contrasted. Moreover, this experiment tested the relationship between attention and the type of awareness that accompanies recognition. Ochsner (2000) suggests that there are memory differences for affective pictures that

3 ATTENTION, MEMORY, AND EMOTION 1237 go beyond recognition. Such differences can occur in the type of awareness that accompanies recognition. Thus, recognition is not always the most sensitive measure of memory performance. The remember/know responses were not a key measure in our study, but were an additional measure to show differences not detected by simple recognition. Participants METHOD Twenty-one participants (15 female, aged 1932 years) from the University of Nottingham took part in this experiment; all had normal/corrected normal vision. Three participants were removed from the eye-tracking analysis due to unsatisfactory eye-tracking data. The experiment was carried out in accordance with the rules set out by the Ethics Committee within the School of Psychology. Participants were free to withdraw at any point, although none chose to do so. Stimuli 192 pictures from the International Affective Picture System (IAPS; Lang, Bradley, & Cuthbert, 2005) were used to create the stimuli; 144 were of neutral affective valence, 24 were positive, and 24 were negative (see Appendix for the IAPS codes of the pictures used). 96 pictures were used as targets (72 neutral, 12 positive, and 12 negative), i.e., pictures that were presented in the study phase and then again in the recognition test. Targets appeared in pairs in the study phase; 24 emotional-neutral (12 negativeneutral, and 12 positive-neutral) and 24 neutral-neutral pairs. The latter were included to balance the number of emotional and neutral pairs. Throughout this paper, neutral pictures that were presented within negative-neutral pairs have been termed negative neutrals; those presented within positive-neutral pairs have been termed positive neutrals; neutral pictures presented within the neutral-neutral pairs have been termed neutral fillers. In the memory phase targets appeared individually along with 96 (72 neutral, 12 positive, and 12 negative) distractors, i.e., images that had not been presented in the study phase. The pictures were matched in terms of content and shape. For example, if the negative target were a picture of an angry face, the neutral target would be a picture of a neutral face. The same matching procedure occurred for targets and distractors (e.g., the negative distractor would be an angry face and the neutral target would be a neutral face). Each stimulus display measured pixels, which equals to of visual angle at a viewing distance of 98 cm. The targets (both in the

4 1238 HUMPHREYS, UNDERWOOD, CHAPMAN study and memory phase) and distractors measured , which equals to avisual angle of at a 98 cm viewing distance. In the study phase, the innermost edge of each target picture was 4.18 from the central fixation point; the distance between the upper edge of the target and the top of the screen, and between the lower edge of the target and the bottom of the screen, was In the emotional-neutral trials, the emotional picture occurred equally on the left and the right hand side of the screen. In the memory phase the targets and distractors were displayed in the centre of the screen. It is important that the pictures only differ in terms of valence and arousal and not in terms of low-level visual features. The emotional valence and arousal of the pictures were compared using the ratings taken from the IAPS (Lang et al., 2005). It is very difficult to calculate the visual complexity of pictures. However, the pictures were matched visually in complexity using subjective matching. To control for other low-level visual features, luminance, complexity, root mean square (RMS) contrast, and red, green, and blue colour saturation (see Nummenmaa et al., 2006) were computed. The means are presented in Table 1; they were subjected to a series of one-way ANOVAs. Table 1 shows that targets only differed in terms of valence and arousal, and not in terms of the low-level visual features. Apparatus The stimuli were presented on a PC with a standard colour monitor. Eye movements were recorded using an iview X RED system from SMI with a remote camera for recording eye position every 20 ms. The spatial accuracy of this system is less than Head movements were restricted by requiring participants to remain on a chinrest while viewing the screen. Stimuli were presented using E-Prime (version 1.1). Design A one-way within-subject design was used for the study phase (valence: neutral filler, positive, negative). Emotional pictures were compared to neutral fillers and not to the neutral pictures they were presented with so that any assumptions of independence were not violated. A one-way withinsubject ANOVA was used for the memory phase (valence: neutral filler, negative, negative neutral, positive, positive neutral). Positive and negative neutrals were included in the memory analysis to assess whether memory for neutral stimuli presented with emotional information is better remembered. Anderson, Wais, and Gabrieli (2006) found that remembering is enhanced for neutral pictures associated with emotional material.

5 ATTENTION, MEMORY, AND EMOTION 1239 TABLE 1 Mean valence, arousal, luminance (0255), complexity value (compressed image size in Kbytes), RMS contrast, and colour saturation (0255) for red, green, and blue channels for each type of picture (standard deviations in parentheses) 1. Negative 2. Negative neutral 3. Positive 4. Positive neutral 5. Neutral filler Valence a ,3,4, , ,2,4, , ,3 (0.74) (0.19) (0.57) (0.27) (0.39) Arousal a ,4, , ,4, , ,3 (0.58) (0.84) (0.85) (0.94) (0.83) Luminance (45.8) (29.1) (29.0) (41.3) (33.6) Complexity (20.46) (19.15) (19.68) (29.07) (27.55) RMS contrast (1.01) (1.09) (0.50) (0.53) (0.72) Red channel saturation (48.07) (36.54) (34.04) (45.83) (37.25) Green channel saturation (47.60) (29.70) (29.93) (43.40) (33.77) Blue channel saturation (36.88) (33.94) (35.40) (42.85) (35.50) Subscripts indicate reliable differences between types of pictures. a 1most negative, 8most positive. Procedure Study phase. A 9-point calibration and validation procedure was repeated several times to ensure that all recordings had a mean spatial error of less than 0.5 deg. Subjects were instructed that they would be presented with pairs of pictures, and that some of the pictures would have an emotional content. Participants were told that for each pair of pictures, they would be required to state which picture they preferred; they were to state left if they preferred the picture on the left and right if they preferred the one on the right; if they had no preference they were to state same. Participants were told to give their response after the presentation of each picture pair and were informed that their eye movements would be recorded during the presentation of the pictures. Finally participants were told that before the presentation of each picture pair a fixation cross () would appear in the centre of the screen and were instructed to focus on this cross until the pictures were presented. The study phase stimuli were presented in a random order. The fixation cross was presented for 750 ms, and each stimulus was shown for 2 s. A text display appeared on the computer screen

6 1240 HUMPHREYS, UNDERWOOD, CHAPMAN after each stimulus was presented, asking participants which picture they prefer (left, right, or same). Memory phase. One week after the study phase participants completed the memory phase. Participants were told that they would be shown pictures presented one at a time; for each picture they should decide whether it was presented previously in the study phase. They were also informed about the different recollective experiences involved in recognition (see remembering and knowing, Gardiner & Java, 1993). The standard remember/know definitions (Rajaram, 1993) were given to participants, although these were adapted to the current experiment (i.e., memory for pictures rather than for words). By using these instructions, it allows the current experiment to be compared with other similar experiments, which typically use these instructions. Participants were instructed that when each picture appeared to state yes if they had seen the picture before, and to state no if they had not. If they responded yes, they had to state whether they remembered or knew the picture by stating either remember or know. As in the study phase, they were told that a fixation cross () would appear in the centre of the screen before the presentation of each picture, and to focus on this cross until the picture was presented. They were also told to respond as quickly and as accurately as possible. The memory stimuli were presented in a random order. The fixation cross () appeared for 750 ms. Eye-tracking results RESULTS The measures taken were (1) time taken to first fixate on the target picture, i.e., the time from the onset of the stimulus display up to the point of first fixation upon the target picture; (2) the number of fixations before first fixation of the target picture, i.e., the number of fixations from the onset of the stimulus display up to the point of first fixation upon the target picture; (3) the number of fixations on the target picture; (4) the mean fixation duration on the target; and (5) the total inspection duration of the target, i.e., the sum of all fixations on the target, independent of sequence or fixations elsewhere. The fixation detection algorithm that was used required a minimum fixation duration of 80 ms and used a dispersion threshold of 200 pixels. The means and standard deviations of the eye-tracking measures for the different types of target pictures are presented in Table 2. Table 2 shows that emotional pictures were looked at after a similar amount of time and number of fixations to neutral pictures; there was no main effect of valence on time to first fixation, F(2, 34)2.230, MSE , nor on number of fixations before first fixation,

7 ATTENTION, MEMORY, AND EMOTION 1241 TABLE 2 Mean eye-tracking measures for negative, positive, and neutral filler pictures (standard deviations in parentheses) Time to first fixation (ms) No. fixations before first fixation Number of fixations Fixation duration (ms) Total inspection duration (ms) Negative (101.9) 1.8 (0.3) 2.2 (0.5) (71.8) (165.5) Positive (100.9) 1.8 (0.3) 2.6 (0.5) (83.2) (192.2) Neutral filler (67.5) 1.9 (0.2) 2.4 (0.5) (60.4) (166.1) F(2, 34)1.521, MSE However, positive pictures attracted the most fixations and the greatest amount of total inspection time throughout the trial; negative pictures were given a reduced number of fixations. Indeed there was a main effect of valence on number of fixations, F(2, 34)9.542, MSE0.935, pb.001, and total inspection time, F(2, 34)11.247, MSE , pb.001. Tukey post hoc analyses showed that positive, q6.15, pb.001, and neutral filler, q3.58, pb.05, pictures received a greater number of fixations than negative pictures; positive pictures received more inspection time than negative, q6.68, pb.001, and neutral filler q 3.87, pb.05, pictures. Although there was a slight tendency for positive pictures to be fixated on for longer than negative and neutral filler pictures, this was not a reliable difference, F(2, 34)1.494, MSE Memory results The mean percentage correct for each type of picture is shown in Table 3. These percentages show that memory performance was highest for negative TABLE 3 Mean percentage correct, recognition sensitivity (A ), recollection (rec), and familiarity (Fd ) for each type of picture (standard deviations in parentheses) % correct A rec Fd Negative (10.1) (0.10) (0.17) (0.83) Negative neutral (12.2) (0.11) (0.21) (0.71) Positive (8.9) (0.09) (0.23) (0.87) Positive neutral (7.5) (0.10) (0.20) (0.35) Neutral filler (9.1) (0.09) (0.18) (0.57)

8 1242 HUMPHREYS, UNDERWOOD, CHAPMAN pictures. The measures of interest were recognition sensitivity, recollection, and familiarity. Recognition sensitivity was measured by calculating A : higher A values indicate greater sensitivity to discriminating between old and new items. A was calculated using Grier s (1971) equation. When memory performance was below chance, a modified version of this equation was used (Aaronson & Watts, 1987; Snodgrass & Corwin, 1988). Positive nontargets were used as new stimuli when computing A for positive targets; negative nontargets were used for negative targets; positive neutral nontargets were used for positive neutral targets; negative neutral nontargets were used for negative neutral targets; neutral filler nontargets were used for neutral filler targets. A was calculated this way because targets were matched, in terms of content and shape, to nontargets. This method allowed memory for emotional targets to be compared specifically to similar nontargets. Recollection and familiarity were measured by calculating recollection (rec) and familiarity (Fd ); recollection based on remember hits and false alarms, and familiarity based on know hits and false alarms, respectively (hits and false alarms were counted according to Yonelinas, Kroll, Dobbins, Lazzara, & Knight, 1998, p. 339). Higher rec and Fd scores indicate an increased contribution of recollection and familiarity, respectively. The means and standard deviations of the memory measures for the different types of pictures are presented in Table 3. Table 3 shows that memory performance was highest for negative pictures; this was reflected by recognition sensitivity and recollection. There was a main effect of valence on both A, F(4, 80)5.191, MSE 0.005, pb.001, and recollection F(4, 80)6.874, MSE0.176, pb Tukey post hoc analyses revealed that A was higher for negative pictures than for positive neutral, q5.18, pb.01, negative neutral, q 5.50, pb.01, and positive, q4.98, pb.01, pictures. Furthermore, negative pictures were more likely to be recollected than positive neutrals, q6.92, pb.001, neutral fillers, q5.62, pb.01, positive pictures, q4.97, pb.01, and than negative neutrals, q4.46, pb.05. Although there was a slight tendency for increased familiarity for positive pictures, there was no main effect of valence on familiarity, F(4, 80)1.309, MSE Item analysis The analyses done so far are useful in demonstrating attention and memory patterns but they do not examine the link between attention and memory directly. An item analysis was carried out to establish whether the eyetracking data predicts memory performance in general, as well as memory for emotional pictures. Point-biserial correlations were calculated between

9 ATTENTION, MEMORY, AND EMOTION 1243 TABLE 4 Average correlation coefficients (r) between the eye-tracking measures and hits for the complete set of stimuli and for each stimulus category All Negative Negative neutral Positive Positive neutral Neutral fillers Time to first fixation No. fixations before first fixation No. fixations Fixation duration Total inspection duration hits and each of the eye-tracking measures for each participant; correlations were calculated including all the pictures, and were also done for each type of picture (i.e., positive, negative, positive neutral, negative neutral, and neutral filler). These correlations were normalised using Fisher s z transformation, and were then averaged across participants. T-values were calculated by dividing the mean by the standard error. These t-values were tested against zero, with dfnumber of participants 1 (see Table 4). There was a reliable albeit weak correlation between hits and total inspection time, t(17)4.34, pb.001, as well as between hits and number of fixations, t(17)2.89, pb.05. The correlation between hits and total inspection time increased for negative neutrals, t(17)2.57, pb.05, and for positive neutral pictures, t(17)2.07, pb.1. There was a small yet reliable correlation between inspection time and hits for neutral fillers, t(17)2.51, pb.05. Surprisingly, for positive neutral pictures there was a strong correlation between hits and time to first fixation, t(17)2.68, pb.05, and between hits and number of fixations before first fixation, t(17) 2.68, pb.05. However, the magnitude of these correlations is deceiving when taking into account the variance (i.e., although the correlation between hits and total inspection time for all types of pictures appears to be weaker, it is actually more statistically significant). DISCUSSION The current experiment demonstrates that enhanced memory for negative pictures can occur without increased attention to such images. This was evident from (1) the pattern of eye-tracking and memory results and (2) an item analysis conducted on the data. In addition, this experiment highlights some implications for studies of attention to emotional stimuli.

10 1244 HUMPHREYS, UNDERWOOD, CHAPMAN Pattern of eye-tracking and memory results There was increased attention to positive pictures and decreased attention to negative pictures during picture viewing; positive pictures were given an increased amount of inspection time than negative and neutral filler pictures; negative pictures received fewer fixations in comparison to positive and neutral filler pictures. If attention predicted memory performance one would expect enhanced memory only for positive pictures in the current experiment. However, there was a strong memory advantage for negative pictures, but no such advantage for positive pictures; A was reliably higher for negative pictures than for positive, negative neutral, and positive neutral pictures; negative pictures were more likely to be recollected than all types of neutral pictures and than positive pictures. Moreover, the enhanced memory for negative images appears to be due to their emotional valence (i.e., their negativity); if it were simply emotional arousal that produced this effect, one would also expect enhanced memory for positive pictures over neutral pictures. In general, the pattern of eye-tracking and memory results suggest that enhanced memory for emotional images was not caused by increased attention to such stimuli. The item analysis This analysis showed that there was a general relationship between inspection time and hits, irrespective of emotional valence. This relationship increased for positive neutrals and negative neutrals, yet no such increases occurred for emotional pictures. These results suggest that although attention can predict memory performance in general, the emotional memory advantage for images cannot always be explained through increased attention to emotional pictures. These results support studies showing that memory for emotional stimuli is not related to processing time (e.g., Guy & Cahill, 1999; Harris & Pashler, 2005; Kern et al., 2002). This paper is not advocating that there is no causal relationship between attention to, and memory for, emotional pictures. However, it is surprising that the results do not show reliable correlations if a causal relationship does exist. Implications for studies of attention to emotional stimuli There was no evidence of early attentional biases to emotional pictures in the current experiment, conflicting with a number of previous studies (e.g., Calvo & Lang, 2004; Calvo et al., 2007; Nummenmaa et al., 2006). This lack of effect in the current experiment could be due to the nature of the preference task, which required participants to think about the pictures in

11 ATTENTION, MEMORY, AND EMOTION 1245 terms of their feelings towards them. Since all types of pictures (even neutral pictures) can have an emotional significance to individuals, participants needed to inspect the images in more detail in order to decide how they felt about them, hence there was no capture of attention by emotional pictures. This suggests that there must be some control over early attention allocation and agrees with studies showing that the early distribution of attention is not automatic (e.g., Schupp et al., 2007). The increased attention to positive pictures that occurred throughout the trial highlights the need for the literature to focus on how task demands can determine attention allocation. Positive pictures could have attracted increased attention in the current experiment due to the nature of the preference task; positive pictures were labelled as high priority and were thus given enhanced attention. Furthermore, although Calvo and Lang (2004) did not find that positive pictures continue to attract attention once they had been looked at, this could be attributed to the arousal levels of the pictures used in their study; the positive and neutral stimuli were equivalent in terms of arousal. REFERENCES Original manuscript received February 2009 Revised manuscript received October 2009 First published online July 2010 Aaronson, D., & Watts, B. (1987). Extensions of Grier s computational formulas for A and B to below-chance performance. Psychological Bulletin, 102, Anderson, A. K., Wais, P. E., & Gabrieli, J. D. (2006). Emotion enhances remembrance of neutral events past. Proceedings of the National Academy of Sciences, USA, 103, Bradley, M. M., Greenwald, M. K., Petry, M. C., & Lang, P. J. (1992). Remembering pictures: Pleasure and arousal in memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 18, Cahill, L., & McGaugh, J. L. (1995). A novel demonstration of enhanced memory associated with emotional arousal. Consciousness Cognition, 4, Calvo, M. G., & Lang, P. J. (2004). Gaze patterns when looking at emotional pictures: Motivationally biased attention. Motivation and Emotion, 28, Calvo, M. G., Nummenmaa, L., & Hyönä, J. (2007). Emotional and neutral scenes in competition: Orienting, efficiency, and identification. Quarterly Journal of Experimental Psychology, 60, Christianson, S.-Å., Loftus, E. F., Hoffman, H., & Loftus, G. R. (1991). Eye fixations and memory for emotional events. Journal of Experimental Psychology: Learning, Memory, and Cognition, 17, Gardiner, J. M., & Java, R. I. (1993). Recognizing and remembering. In A. F. Collins, S. E. Gathercole, M. A. Conway, & P. E. Morris (Eds.), Theories of memory (pp ). Hove, UK: Lawrence Erlbaum Associates Ltd. Grier, J. B. (1971). Nonparametric indexes for sensitivity and bias: Computing formulas. Psychological Bulletin, 75,

12 1246 HUMPHREYS, UNDERWOOD, CHAPMAN Guy, S. C., & Cahill, L. (1999). The role of overt rehearsal in enhanced conscious memory for emotional events. Consciousness and Cognition, 8, Hamann, S. (2001). Cognitive and neural mechanisms of emotional memory. Trends in Cognitive Science, 5, Harris, C. R., & Pashler, H. E. (2005). Enhanced memory for emotionally charged pictures without selective rumination. Emotion, 5, Kensinger, E. A., Garoff-Eaton, R. J., & Schacter, D. L. (2006). Memory for specific visual details can be enhanced by negative arousing content. Journal of Memory and Language, 54, Kern, R. P., Libkuman, T. M., & Otani, H. (2002). Memory for negatively arousing and neutral pictorial stimuli using a repeated testing paradigm. Cognition and Emotion, 16, Kern, R. P., Libkuman, T. M., Otani, H., & Holmes, K. (2005). Emotional stimuli, divided attention, and memory. Emotion, 5, LaBar, K. S., & Phelps, E. A. (1998). Arousal-mediated memory consolidation: Role of the medial temporal lobe in humans. Psychological Science, 9, Lang, P. J., Bradley, M. M., & Cuthbert, B. (2005). International Affective Picture System (IAPS): Digitized photographs, instruction manual, and affective ratings (Tech. Rep. No. A-6). University of Florida, Gainesville, FL. Maljkovic, V., & Martini, P. (2005). Short-term memory for scenes with affective content. Journal of Vision, 5, Nummenmaa, L., Hyönä, J., & Calvo, M.G. (2006). Eye-movement assessment of selective attentional capture by emotional pictures. Emotion, 6, Ochsner, K. N. (2000). Are affective events richly remembered or simply familiar? The experience and process of recognizing feelings past. Journal of Experimental Psychology: General, 129, Rajaram, S. (1993). Remembering and knowing: Two means of access to the personal past. Memory and Cognition, 2(1), Schupp, H. T., Stockburger, J., Bublatzky, F., Junghöfer, M., Weike, A. I., & Hamm, A. O. (2007). Explicit attention interferes with selective emotion processing in human extrastriate cortex. BMC Neuroscience, 8, 16. Snodgrass, J. G., & Corwin, J. (1988). Pragmatics of measuring recognition memory: Applications to dementia and amnesia. Journal of Experimental Psychology: General, 117, Talmi, D., Schimmack, U., Paterson, T., & Moscovitch, M. (2007). The role of attention and relatedness in emotionally enhanced memory. Emotion, 7(1), Yonelinas, A. P., Kroll, N. E. A., Dobbins, I., Lazzara, M., & Knight, R. T. (1998). Recollection and familiarity deficits in amnesia: Convergence of rememberknow, process-dissociation, and receiver operating characteristic data. Neuropsychology, 12, APPENDIX The IAPS number for targets (outside parentheses) and the corresponding distractors (inside parentheses) were: (a) positive pictures: 2000 (2010), 7470 (7480), 7250 (7260), 5480 (5910), 7200 (7340), 2058 (2070), 5890 (5300), 2020 (2630), 7350 (7351), 7410 (7430), 5010 (5020), and 7501 (7510); (b) positive neutral pictures: 2214 (2215), 7820 (7096), 7233 (7006), 7170 (7175), 7010 (7041), 2191 (5720), 7020 (7040), 2210 (2500), 7211 (7190), 7207 (7179), 5520 (5532), and 7560 (7595); (c) negative pictures: 2110 (2100), 9800 (9810), 2120 (2230), 3180 (3181), 9109 (9401), 2692 (6190), 2900 (2810), 2800 (2278), 9561 (9571), 6610 (6800), 6020 (6000), and 9440 (9341); (d) negative neutral pictures: 2493 (2200), 2190 (2635), 2220 (2780), 2441 (2830), 6150 (7490),

13 ATTENTION, MEMORY, AND EMOTION (7705), 2840 (7503), 9070 (2270), 1945 (1726), 7050 (7000), 7030 (7025), and 7830 (7160); and (e) neutral filler pictures: 7034 (7110), 7038 (7031), 2440 (2381), 7182 (7183), 5500 (5530), 5510 (5534), 7130 (7140), 7500 (7493), 7495 (7496), 7186 (7187), 2383 (2372), 2357 (2575), 2870 (2749), 2520 (2480), 7009 (7035), 5390 (5395), 7002 (7205), 6900 (6910), 5533 (5531), 7185 (7900), 7590 (7570), 2595 (2435), 2516 (2510), 2514 (2518), 7080 (7004), 7060 (7150), 2410 (2487), 7237 (7238), 5120 (5130), 5740 (5731), 7037 (7039), 7491 (7545), 7640 (7036), 7100 (7095), 2393 (7550), 8010 (8465), 2850 (2745.1), 2495 (2570), 7235 (7217), 2272 (2235), 7710 (7234), 6930 (6940), 5535 (7161), 7090 (7184), 8192 (8160), 2385 (2271), 2280 (2240), and 9210 (5875).