Journal of Psychophysiology 1/2018 by Hogrefe

Volume 32 / Number 1 / 2018

Journal of

Psychophysiology

Journal of Psychophysiology

Editor-in-Chief Michael Falkenstein Editorial Board Markus Breimhorst Tavis Campbell Ritobrato Datta Nicola Ferdinand Patrick Gajewski Edward Golob Sien Hu Julian Koenig Cristina Ottaviani Patrick Papart Daniel S. Quintana Walter Sannita Henrique Sequeira Franck Vidal Lin Wang Juliana Yordanova

An International Journal

Contents Articles

Journal of Psychophysiology (2018), 32(1)

Evaluative and Psychophysiological Responses to Short Film Clips of Different Emotional Content Luis Aguado, Marı́a Fernández-Cahill, Francisco J. Román, Iván Blanco, and Javier de Echegaray

An ERP Investigation of Object-Scene Incongruity: The Early Meeting of Knowledge and Perception Fabrice Guillaume, Sophie Tinard, Sophia Baier, and Stéphane Dufau

Burnout of the Mind – Burnout of the Body? Claudia Traunmüller, Kerstin Gaisbachgrabner, Helmut Karl Lackner, and Andreas R. Schwerdtfeger

Ó 2018 Hogrefe Publishing

Article

Evaluative and Psychophysiological Responses to Short Film Clips of Different Emotional Content Luis Aguado,1 María Fernández-Cahill,2 Francisco J. Román,3,4 Iván Blanco,1 and Javier de Echegaray1 1

Facultad de Psicología, Universidad Complutense de Madrid, Spain Instituto de Investigación “12 de octubre,” Madrid, Spain

2 3

Facultad de Psicología, Universidad Autónoma de Madrid, Spain

Decision Neuscience Laboratory, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign,

Urbana, IL, USA

Abstract: The study presents self-report and psychophysiological data obtained in response to short film clips representing scenes related to different emotions. This was done in order to obtain evidence on the structure of positive and negative affective states following a combined dimensional/categorical approach to emotion and based on responses to stimuli that are more realistic than the static pictures usually employed in the study of emotion. Affective ratings and self-report measures showed a differential structure of the response to positive and negative films (Experiment 1). While all negative films were rated as low in valence and high in arousal, positive films were differentiated into arousing (happy and pleasure contents) and de-arousing (relax contents) categories. A more complex pattern emerged in Experiment 2, using two psychophysiological measures that are differentially sensitive to the main affective dimensions of valence and arousal, skin conductance response (SCR) and facial electromyography (fEMG). First, high arousal positive and negative films produced larger skin conductance responses. Second, fEMG measures showed differentiated response patterns within the positive and negative film categories. Within the positive category, happy and relaxing films had opposed effects, with happy films increasing and relax films decreasing activity over the zygomaticus muscle region. In the case of negative films, only those eliciting disgust produced a differentiated pattern of fEMG activity characterized by large corrugator responses and a modest increase of zygomatic responses. These results are discussed in relation to the adequacy of the dimensional and categorical approaches to emotion, the usefulness of combining subjective and psychophysiological measures, and the advantages of using realistic, dynamic stimuli for the study of emotion. Keywords: emotional films, arousal, valence, skin conductance, facial EMG

Contemporary studies of emotion have followed one of two different but complementary approaches to the characterization of affective experience and response. Dimensional approaches organize the affective space based on global elements of emotion, such as valence and arousal (e.g., Bradley & Lang, 2000a, 2000b). According to this approach, affective states can be differentiated based on specific values of these elemental dimensions, being defined, for example, as highly positive and arousing or slightly negative and de-arousing. In contrast with this, the discrete emotions approach proposes a differentiation of affective states in terms of their specific contents (e.g., threat-related vs. loss-related, Ekman, 1992; Izard, 1993), leading to different emotion categories such as fear or sadness. Studies using pictures as eliciting stimuli and self-report and psychophysiological measures as dependent measures have provided evidence supporting the dimensional approach. For example, some psychophysiological Ó 2016 Hogrefe Publishing

responses are differentially sensitive to variations in the two basic dimensions of valence and arousal. While the skin conductance response is sensitive to variations in arousal, with larger responses to more arousing stimuli (e.g., Bradley, Codispoti, Cuthbert, & Lang, 2001; Bradley, Codispoti, Sabatinelli, & Lang, 2001), the response of facial muscles measured through facial electromyography (fEMG) is more sensitive to valence, with different patterns of muscle activity for positive and negative stimuli (e.g., Cacioppo, Petty, Losch, & Kim, 1986). Albeit less abundant, research with picture stimuli has also provided results supporting the discrete emotions or categorical approach. For example, differences have been shown between the precise pattern of facial and visceral activity evoked while viewing fear and disgust pictures (Bradley, Codispoti, Sabatinelli, & Lang, 2001; Lang, Greenwald, Bradley, & Hamm, 1993). Behavioral and neuroscientific research on emotion has used different procedures to induce mood changes and Journal of Psychophysiology (2018), 32(1), 1–19 DOI: 10.1027/0269-8803/a000180

elicit evaluative and psychophysiological responses in experimental participants (see Coan & Allen, 2007, for a collection of chapters on emotion elicitation techniques). Among those using visual stimuli, pictures showing affectively positive and negative objects or scenes (Lang, Bradley, & Cuthbert, 2008) have been most popular. Static visual stimuli have the advantage of allowing precise control of timing, which is a crucial requisite in most experimental paradigms. Moreover, briefly presented static stimuli do not change over time in terms of emotional intensity, as would be the case if animated images were used. However, the flip side of these methodological advantages is the reduced realism of static pictures that lack the dynamism and continuous change of real-life events. An alternative to static pictures is the use of films or film extracts that describe emotionally meaningful scenes. Although the use of this tool is not generalized, there are now several published reports describing collections of film clips that can be used in the study of emotion (Carvalho, Leite, Galdo-Álvarez, & Gonçalves, 2012; Gross & Levenson, 1995; Hewig et al., 2005; Philippot, 1993; Schaefer, Nils, Sanchez, & Philippot, 2010; see Rottenberg, Ray, & Gross, 2007, for a review). Emotional film scenes also have their own advantages. Firstly, films are especially effective in inducing mood changes and may be superior to other induction procedures (e.g., Palomba, Sarlo, Angrilli, Mini, & Stegagno, 2000; Simons, Detenber, Roedema, & Reiss, 1999; Simons, Detenber, Reiss, & Shults, 2000; Westermann, Spies, Stahl, & Hesse, 1996). Secondly, the dynamic nature of film scenes makes this a more realistic procedure to induce emotional changes, as it is closer to real-life emotions produced by experiences where events unfold over time. In effect, emotional film excerpts have been used successfully to elicit experiential (e.g., Gross & Levenson, 1995; Schaefer et al., 2010) and physiological changes (e.g., Christie & Friedman, 2004; Hubert & de Jong-Meyer, 1990; Kreibig, Wilhelm, Roth, & Gross, 2007). Similarly, characteristic patterns of brain activity have been reported in the presence of emotional film clips, compared to films of neutral content (e.g., Goldberg, Preminger, & Malach, 2014; Karama, Armony, & Beauregard, 2011). Based on this evidence, the use of film clips seems a suitable method to study emotion as their characteristics are closer to the dynamic and evolving nature of real-life emotional events. In this way, the use of this type of stimuli can improve the generalizability of basic research on emotion. Experts in the use of films to elicit emotion have warned about the low temporal resolution of films in terms of emotional intensity and the danger that long excerpts may create heterogeneous epochs of data with significant variations in intensity (Rottenberg et al., 2007). However, most previous collections of emotion films include stimuli Journal of Psychophysiology (2018), 32(1), 1–19

L. Aguado et al., Responses to Emotional Clips

of different durations and in some cases excerpts lasting several minutes have been used. For example, the larger and more complete database of emotion films published to date (Schaefer et al., 2010) contains 70 clips with durations that range from 1 min to over 6 min. Although in the study by Hewig et al. (2005) shorter clips were included, duration varied from 29 to 236 s. Though long and varying durations may be appropriate to elicit overall mood or emotion changes that can be measured retrospectively via self-report by the participant, they are more problematic when the interest is in online gathering of objective physiological or brain activity data that are subject to continuous variation. In this case, averaging over the entire duration of films that contain segments of different emotional intensity increases the risk of reducing the sensitivity of the measure in question. The use of short films with a fixed duration is clearly more appropriate in this type of study. Moreover, when choosing the appropriate duration of film fragments, consideration must be paid to the temporal dynamics of the target response system. Some indexes of emotional reactivity are fast, like facial EMG responses, which reach maximum amplitude during the first 500 ms after stimulus onset (e.g., Dimberg, 1990). In contrast with this, other indexes such as heart rate changes and electrodermal activity are slower and take several seconds to reach their maximum peak. An additional shortcoming of long film fragments is that differences may appear between films in the complexity of the narrative. In fragments lasting several minutes such as those used in some studies (e.g., Schaefer et al., 2010), relatively complex plots can be developed, demanding elaborate processing mechanisms on behalf of the viewer and increasing the difficulty of interpreting associated changes in biological measures. As an alternative to this, much shorter film clips can be used to present peak emotional events that are not embedded in complex narratives or require further contextual information. The goal of the present study is twofold. First, we describe in Experiment 1 a new set of short film clips with a fixed 10 s duration that can be useful in the study of affect and emotion using psychophysiological measures. This duration is long enough to allow measurement of the most popular and sensitive index of emotional arousal, skin conductance, while at the same time allowing the measurement of changes in responses that are sensitive to affective valence such as facial muscle responses measured through the fEMG technique. The decision to use 10 s clips was also based on our attempt to create a collection of dynamic snapshots describing self-contained, single events that could be easily understood and appraised as affectively meaningful in the absence of further contextual information (e.g., “Someone moving a bloodstained corpse” or “Dolphins jumping over the sea”). This format maintains Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

the characteristic single-event nature of more usual still pictures while adding, at the same time, further emotional power through the more lively and compelling dramatism of dynamic images. Clips of fixed but longer durations have been used in previous studies, such as the study by Carvalho et al. (2012), who used 40 s clips. Moreover, in this last study the clips were rated in terms of the valence, arousal, and dominance dimensions but not in terms of emotion category, unlike our study. The contents of the clips we selected were related to different specific emotions since one of our main goals was to prepare a film collection that could be used to study the reactions associated to different emotional states. The ability of our film collection to elicit differentiated psychophysiological response patterns related to different discrete emotions was tested in Experiment 2 using electrodermal activity and fEMG measures in response to positive (happy and relax), negative (fear and disgust), and neutral film clips.

Experiment 1 Materials and Method Stimulus Selection The first step in the study involved the selection of a set of 50 film excerpts representing a range of contents related to different varieties of positive and negative affect together with a set of control films showing affectively neutral scenes. The set comprised 50 film fragments (20 positive, 20 negative, 10 neutral), all with a fixed duration of 10 s. Candidate excerpts were identified from a larger set of independent feature films and television documentaries. These sources were chosen to avoid possible effects of familiarity and prior knowledge that might mediate the emotional impact of excerpts from more popular films already seen by the participants. Initial adscription of the excerpts to the different categories of valence and content was determined a priori by the experimenters. Several target contents were chosen based on the categories of positive and negative images in the International Affective Picture System (IAPS) collection. Three categories of positive clips were selected: nature (underwater scenes, attractive animals, and landscapes), babies (babies alone or interacting with peers or mother), and couples/families (couples, erotic and family scenes). Studies with the IAPS collection have shown that these positive contents can be discriminated in terms of electrodermal activity and fEMG

pattern (Bradley, Codispoti, Sabatinelli, & Lang, 2001; Ribeiro, Teixeira-Silva, Pompéia, & Bueno, 2007). As to the negative films, excerpts representing disgust (disgusting scenes involving human beings or animals) and aggression/ threat scenes (human aggression, injuries, or natural disasters) were selected. Studies with IAPS images have shown that these categories of negative content produce differentiated psychophysiological patterns (e.g., Bradley, Codispoti, Cuthbert, & Lang, 2001; Bradley, Codispoti, Sabatinelli, & Lang, 2001). Clips representing neutral scenes (human beings performing daily routines and urban scenes) were also selected as a control condition. After identifying the excerpts of interest, they were edited to remove soundtrack and mastheads when necessary. We decided to use silent clips, where events are represented visually without the influence of dialogs or background music that might condition the interpretation of the scene and influence its emotional impact. All excerpts were cut to 10 s duration. Detailed information about the clips is given in Appendix A.1 Participants A total of 38 students (19 males, 19 females, age 18–30 years, M = 22.29, SD = 2.17) from the Universidad Complutense of Madrid voluntarily took part in the study in exchange for course credits. All participants reported having no history of any neurological or psychiatric disorders. Informed consent was obtained before starting the experiment. Procedure Stimulus presentation was programmed and controlled by software E-Prime 2.0 (Psychology Software Tools, Pittsburgh, PA). The stimuli were presented on a 12000 projector screen and responses were collected through written questionnaires. All participants saw the 50 clips in a single session. A booklet was prepared containing instructions to perform the task and the valence and arousal SAM (SelfAssessment Manikin) scales (Bradley & Lang, 1994) for each clip. Participants were asked to rate each clip in terms of valence and arousal and to report the emotion they felt while watching each film, selecting from a list of eight word pairs the one that better represented how they felt while watching the clip (“Joy/Happiness,” “Pleasure/ Well-Being,” “Peace/Relaxation,” “Fear/Anxiety,” “Anger/Rage,” “Sadness/Sorrow,” “Disgust/Revulsion,” and “Neutral/No Emotion”). Each trial would start by presenting a film clip during 10 s, followed by a 30 s interval to respond. The order of stimulus presentation was varied randomly.

The complete clip collection can be obtained from the authors in CD-ROM format. Requests should be addressed to the corresponding author: laguadoa@ucm.es.

Ó 2016 Hogrefe Publishing

Journal of Psychophysiology (2018), 32(1), 1–19

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Results As the goal of this study was to obtain initial validation data for our film clip collection, analyses were carried out at the stimulus level. For all repeated-measures ANOVAs reported, the Greenhouse-Geisser correction was applied when the sphericity assumption was violated. Post hoc analyses were performed using the Bonferroni correction (significant when p .05). Valence and Arousal Ratings as a Function of Film Valence Ratings of valence and arousal correlated negatively (r = .77, p < .001) indicating that clips receiving lower ratings on the valence dimension were also rated as more arousing. Mean valence and arousal ratings for the positive, negative, and neutral film clips are presented in Figure 1. For the valence ratings, a highly significant effect of valence category was obtained, F(2, 47) = 381.148, p < .001, η2 = .942. Post hoc comparisons showed that all categories were different from each other, with positive clips resulting as the most pleasant, followed by the neutral and negative clips (all ps < .001). A significant effect was also obtained for the arousal ratings, F(2, 47) = 64.428, p < .001, η2 = .733. Post hoc comparisons showed that negative clips were rated as significantly more arousing than neutral and positive clips (both ps < .001). Valence and arousal data for each individual clip are presented in Appendix B. Subjective Experience and Emotion Categories A clip was ascribed to a given emotion category when it reached a cut-off point of 50% choices of the corresponding emotion word (four times higher than the probability of being chosen randomly). Eleven clips had to be excluded for failing this criterion. Moreover, categories where only one clip met this criterion were excluded. This was the case of the anger/rage category. One of the neutral clips was excluded because the selection of positive emotion labels was over 50%. Thus, the final selection for this analysis comprised 37 clips distributed in 7 categories, happy (6), pleasure (2), relax (5), fear (5), sad (5), disgust (5), and no emotion (9). All films categorized in the peace/relaxation category represented pleasant nature scenes without human actors (21A, 21B, 21C, and 21G), except one (clip 21D) in which a woman contemplates the twilight. All clips included in the happiness/joy category (21H, 22A, 22B, 22E, 23A, and 23B) represented scenes describing affiliative situations where babies, children, or young animals appear in play situations or in positive interactions with peers or adults. Finally, the two clips assigned to the pleasure/ well-being category (23C and 23D) represented heterosexual couples in erotic attitude. As for the negative clips, the disgust category included five film fragments representing the shedding of human body fluids Journal of Psychophysiology (2018), 32(1), 1–19

Figure 1. Mean valence and arousal ratings for the positive, negative, and neutral clip categories in Experiment 1.

(11A, 12A, and 12H) or disgusting animals (12G and 12I), two classes of stimuli that are among the most common releasers of disgust reactions (Haidt, McCauley, & Rozin, 1994). Sadness clips represented human actors or animals in different life-threatening situations. Three of these clips (11C, 11F, and 12E) involved bloodshedding, while two additional fragments represented a baby’s medical intubation (12J) or a man showing the stump of his arm (12C). Finally, the fear category included two clips (11G and 11H) representing destruction caused by natural disasters, threat of human or animal origin (11I and 11J), and a dying woman (12D). Detailed information on the self-report results for each clip is given in Appendix C. The thematic content was fairly consistent within each positive emotion category. In contrast, the sadness/sorrow and fear/anxiety categories included clips of relatively heterogeneous content. Based on the percentage choice of the different emotion labels that the participants used to describe their emotional experience an ambiguity index (AI) was computed for each individual film (FernándezCahill, 2012). This index allowed an estimation of the extent to which a particular clip had induced different emotional states. The AI Index was calculated according to the following formula:

AI ¼

Xi X max

ð1Þ

where Xi is the average percentage choice of all emotion labels except the one most frequently selected and Xmax is the percentage choice of the most frequently selected label. Using this formula, higher AI values indicate higher ambiguity, with 0 indicating no ambiguity and 1 maximum ambiguity. The AI values for each film clip are given in Appendix C. The analysis based on specific emotion categories yielded a significant effect, F(6, 37) = 4, p < .001, η2 = .45. Post hoc comparisons Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Figure 2. Mean valence and arousal ratings for clips of different emotion content in Experiment 1.

showed that fear and sad clips were significantly more ambiguous than neutral ones (ps < .05). Valence and Arousal Ratings According to Emotion Category Figure 2 presents the average valence and arousal ratings according to the emotion categories described above. Independent one-way ANOVAs yielded a highly significant effect of Emotion, F(6, 37) = 111, p < .001, η2 = .96, and F(6, 37) = 63.32, p < .001, η2 = .93, for the valence and arousal ratings, respectively. Post hoc comparisons showed significant differences between the neutral clips and the rest of categories and between each positive category and each of the negative categories (ps < .001). No significant differences in valence ratings were obtained between clips of similar valence and different emotion content. Nevertheless, differences between clips of positive valence did appear in the case of arousal ratings. Relaxing films were rated as significantly less arousing than the other two positive categories of positive films (pleasure or happiness) (ps .01). No differences in arousal were observed between negative emotion categories.

Discussion Evaluative ratings of a new set of short film clips with emotional content yielded the expected differences between positive and negative films. However, arousal ratings revealed that negative films were perceived in general as more arousing than both positive and neutral ones. Average arousal of positive clips was relatively low and no different from that of neutral films. Consistent with Ó 2016 Hogrefe Publishing

this, the less populated sections of the affective space defined by the combination of valence and arousal ratings were those corresponding to the negative/low arousal and positive/high arousal quadrants. The particular distribution of negative stimuli over the affective space observed in the present study is not uncommon in research on emotion. In studies with the IAPS collection the negative/low arousal quadrant is usually the less populated section of the affective space (e.g., Lang, Bradley, & Cuthbert, 2008; Ribeiro, Pompéia, & Bueno, 2005) and typical contents include nature pollution, starving children, and cemeteries that were not represented in our clip collection. On the other hand, while pictures of erotica appear frequently in the positive/high arousal quadrant, only 3 of our 20 positive films represented this type of content. The more represented contents in the positive film category were babies and nature scenes that usually tend to receive low arousal ratings. Thus, although not all sections of the affective space were equally represented in our film collection, valence and arousal ratings were consistent with those found for similar contents with still pictures. The emotion categories selected according to the selfreport measures were not similarly homogeneous in terms of thematic content. Sad and fear films were the most ambiguous, that is, the ones that produced more varied self-reported emotions. Differences in rated arousal appeared between positive films of different emotion content. Relaxing films were evaluated as significantly less arousing than happy and pleasure films. This is consistent with previous studies that have found a differentiation between positive arousing and relaxing pictures (e.g., Bradley, Codispoti, Cuthbert, & Lang, 2001; Bradley, Journal of Psychophysiology (2018), 32(1), 1–19

Codispoti, Sabatinelli, & Lang, 2001; Ribeiro et al., 2007). The absence of differences in arousal between negative films is not surprising given that most negative clips contained scenes associated to different varieties of threat, physical harm, or strong disgust. In summary, the collection of film clips here described provides a set of dynamic emotional stimuli that show consistent differences in terms of basic affective dimensions and emotional content. Moreover, the set includes films that are effective in inducing differentiated emotional states as measured via self-report. These characteristics, together with the short and fixed duration of the films, seem particularly suited to the study of the psychophysiological differentiation of affective states. In Experiment 2, we present psychophysiological data obtained with a subset of clips belonging to different positive and negative emotion categories.

Experiment 2 The goal of the present experiment was to study the different patterns of physiological reactivity in response to positive and negative clips of different emotion content. To this end, we employed two measures that are routinely used in emotion research, electrodermal activity, and facial EMG. These two measures were chosen because they are differentially sensitive to variations in the valence and arousal dimensions. Increased electrodermal activity is usually observed in the presence of highly arousing stimuli (e.g., Greenwald, Cook, & Lang, 1989; Lang et al., 1993). On the other hand, affectively positive and negative stimuli increase activity on the Zygomaticus Major (ZM) and Corrugator Supercilii (CS) muscle regions, respectively (Bradley, Codispoti, Cuthbert, & Lang, 2001; Greenwald et al., 1989; Lang et al., 1993). There is abundant evidence on the ability of emotional pictures to elicit physiological reactions and changes in facial activity (e.g., Bradley et al., 2001; Dimberg, 1990; Greenwald et al., 1989; Lang et al., 1993; for a review see Bradley & Lang, 2007). Although less abundant, there is also evidence on the sensitivity of these measures to the emotional content of films (e.g., Kreibig et al., 2007; Palomba et al., 2000). There are, however, some important methodological and theoretical differences between these two sets of studies. Studies using films usually include a smaller set of stimuli and there are important variations in the contents represented in different studies. Moreover, films of different durations have often been employed in the same study, a characteristic that may be problematic when using physiologically dependent variables. Based on the traditional assumption that emotional states are accompanied by differentiated patterns of physiological Journal of Psychophysiology (2018), 32(1), 1–19

L. Aguado et al., Responses to Emotional Clips

arousal (for recent reviews see Kreibig, 2010; Mauss & Robinson, 2009; Norman, Bernston, & Cacioppo, 2014), studies with films have sought to reveal the patterns of bodily responses associated to different categories of emotional experience. In the present experiment, electrodermal (skin conductance response, SCR) and facial EMG responses were measured in the presence of positive and negative film clips. These variables were selected because of their sensitivity to affective variables. Skin conductance and fEMG are differentially sensitive to the basic affective dimensions of valence and arousal, with skin conductance responses covarying with subjectively rated arousal and fEMG showing different response patterns in response to positively and negatively valenced stimuli. However, conjoint use of these variables may reveal different patterns that would allow us to differentiate the responses to clips of different emotion content, that is, differences that would go beyond those expected based solely on valence and arousal ratings. In fact, studies reporting differentiated patterns of response associated to different discrete emotions have employed multiple measures of psychophysiological activity (e.g., Stemmler, 2004; Stephens, Christie, & Friedman, 2010). Two types of contents were selected for each valence category, happiness and relax for the positive category and fear and disgust for the negative one. Given the characteristics of the clips selected for the present experiment, a key question was the relative role of basic affective dimensions (valence and arousal) and emotion category in determining the pattern of responses to films. In Experiment 1, happy and relaxing films received similar high valence ratings but differed in terms of arousal. On the other hand, fear and disgust films received similar low ratings in valence and similar high ratings in arousal. If the psychophysiological response pattern depends only on valence and arousal, then valence-sensitive measures (fEMG activity) should show no differences between films receiving similar valence ratings and differences in arousal-sensitive measures (electrodermal activity) should appear only between films rated as different in arousal, as is the case of happy and relax films. Response patterns at variance with these predictions would instead reveal an influence of emotion content beyond the basic dimensions of valence and arousal.

Materials and Method Participants A new participant’s sample of 38 students (19 males and 19 females, M = 19.55, SD = 1.49, age 18–24 years) from the Universidad Complutense of Madrid voluntarily took part in this study in exchange for course credits. All participants reported having no history of neurological or psychiatric disorders. Informed consent was obtained before starting the experiment. Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Stimuli and Procedure Thirty film clips were selected from the set described in Experiment 1.2 Assignment of clips to the different emotion categories was based on the self-report data obtained in Experiment 1. The selection contained 11 positive clips, 10 negative clips, and 9 neutral clips. Two positive emotion categories, happiness (6) and relax (5), were selected. As for the negative categories, films representing fear (5) and disgust (5) were selected. The clips were presented on the screen of a 2300 LCD monitor (Samsung SyncMaster 244T), inside a 512 512 pixels square, and on a 50% gray background. The experimental sessions were carried out individually in a soundproof room. The software E-Prime 2.0 was used for stimulus presentation and response collection. Participants were seated at a distance of 50 cm from the computer screen. Note that clips selected in Experiment 2 were less ambiguous (AI index) than clips of the same category not selected for this experiment (see Table 1). A block design was employed, with films of similar valence presented on each of three successive blocks. All participants saw the neutral films first, followed by the positive and negative blocks in a counterbalanced order. Participants were asked to rate each film in terms of valence and arousal by clicking over the appropriate section of the SAM valence and arousal scales presented on the screen. Intertrial interval was 10 s. After finishing the experimental session, the participants were thanked for their contribution and debriefed. SCR and fEMG Signal Acquisition and Analysis The experimental environment was carefully prepared so as to ensure that no electronic devices could contaminate the fEMG/SCR signal. Average temperature in the test room was 22 °C, recording of fEMG and SCR was done through a PowerLabÓ 8/30 system. The SCR signal was registered using ML116 GSR Amp and finger electrodes placed on the volar surface of the distant phalange of the index and middle fingers of the nondominant hand (Cacioppo, Tassinary, & Berntson, 2007). The fEMG signal was registered using four active electrodes corresponding to two distinct bipolar montages. Miniature surface electrodes (4 mm, Ag/AgCl) filled with electrode gel were attached on the left side of the face over the ZM and CS muscle regions, following Fridlund and Cacioppo’s (1986) guidelines. An additional ground electrode was placed on the elbow. Simple motor and cognitive tasks (e.g., eyes closing and opening, counting backwards) were used during participant’s preparation in order to ascertain proper electrode functioning and mask the intention of the experiment. 2

Table 1. Ambiguity index means (Experiment 1) for clips selected and not selected for Experiment 2, according to different content

Neutral

Selected

Not selected

0.020

–

Happy

0.057

0.198

5.829

< .001

4.12

Relax

0.066

0.245

5.902

.002

5.27

Fear

0.104

0.200

2.885

.029

2.35

Disgust

0.078

–

Electrodermal activity was continuously recorded using the LabChartÓ application (ADInstruments, Dunedin, New Zealand) at a 400 Hz sampling rate. Data were segmented into two different epochs per trial. The first epoch corresponded to the pre-stimulus 1,000 ms period and was used as a baseline. The second epoch corresponded to the 2,000–10,000 ms film period. The dependent variable was the amplitude of the Skin Conductance Response (SCR). Baseline electrodermal activity for each block was calculated by averaging over the 1,000 ms period immediately preceding each stimulus. Data corresponding to the first 2,000 ms of each clip were excluded from analysis to avoid possible contamination by orienting responses produced by stimulus onset. Changes in skin conductance that exceeded 0.05 μS were scored as stimulus evoked responses during each trial. Skin conductance responses were baseline-corrected (using the average baseline for the corresponding block) prior to statistical analyses. The Change Score for each stimulus-presentation period was calculated by subtracting the average baseline from the maximum peak within the 2,000–10,000 ms film period. In order to evaluate possible emotional post-effects, a Change Score was also calculated for the 500 ms period immediately following stimulus offset (Change Score-Post). In what follows, we will refer to the change score corresponding to the 2,000–10,000 ms period during clip presentation as Change Score 1 and to the score corresponding to the 5 s period following stimulus offset as Change Score 2. The fEMG was continuously recorded at 1 K/s with an online 50–400 Hz band-pass digital filter. Data were segmented into 11,000 ms epochs, corresponding to clip duration plus a 1,000 ms pre-stimulus period. The signal was full-wave rectified and smoothed over 200 ms periods. The values corresponding to the average fEMG activity during the pre-stimulus period of each clip were used as a baseline. The procedure used by Moody and McIntosh (2011) was employed to analyze the fEMG data. The stimulus-presentation period was divided into two 5,000 ms time bins (t1 and t2) for statistical analysis.

Film clips presented in Experiment 2: Neutral: 00A, 00C, 00D, 00E, 00F, 00G, 00H, 00I, 00J. Happy: 21H, 22A, 22B, 22E, 23A, 23B. Relax: 21A, 21B, 21C, 21D, 21G. Fear: 11G, 11H, 11I, 11J, 12D. Disgust: 11A, 12A, 12G, 12H, 12I.

Ó 2016 Hogrefe Publishing

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L. Aguado et al., Responses to Emotional Clips

Table 2. Valence and arousal ratings for the different emotion content in Experiment 2 Emotion category

Mean valence

SEM

Mean arousal

SEM

Happy

7.65

0.11

5.41

0.22

Relax

7.14

0.15

2.90

0.24

Fear

2.89

0.15

6.73

0.19

Disgust

2.33

0.11

6.65

0.20

Neutral

5.28

0.08

4.52

0.16

Note. SEM = Standard Error of the Mean.

Results Analysis of valence and arousal ratings at the participant level is presented first followed by the analysis of electrodermal and fEMG activity. Valence and Arousal Ratings Average valence and arousal ratings for the five selected film categories are presented in Table 2. Valence and arousal ratings were analyzed in terms of Emotion Content (happy, relax, fear, disgust, and no emotion) and participant Sex. A mixed 5 2 ANOVA of the valence ratings gave a significant main effect of Emotion, F(2.72, 98) = 410, p < .001, η2 = .91, and a significant effect of Emotion Sex interaction, F = 5.09, p < .005, η2 = .12. All post hoc comparisons between emotion categories were significant, indicating that all five clip categories differed in terms of valence. Happy clips were rated as more positive than relax clips (p < .05) and clips of both categories were rated more positively than fear, disgust, and neutral clips (ps < .01). In the case of negative clips, those representing disgust were rated as more negative than fear clips (p < .05) and both categories were in turn rated more negatively than positive and neutral clips (p < .01). Female participants tended to give disgust and fear clips lower valence ratings than male participants (p < .05). A significant effect of Emotion was also found on the arousal ratings, F(2.56, 92) = 80, p < .001, η2 = .69. Post hoc comparisons showed higher arousal ratings for fear and disgust films than for happy, relax, and neutral films. Moreover, happy clips were rated as significantly more arousing than relax clips (all ps < .05).Note. SEM = Standard Error of the Mean.

Electrodermal Activity Figure 3 presents the average SCR change scores for the five emotion categories. A 5 2 2 ANOVA applied to SCR change scores with Emotion (5) and Time (2) as repeated-measures factors and participant Sex as the between-subjects factor gave a significant effect of Emotion, F(2.6, 95) = 8.6, p < .001, η2 = .19. No other significant effects were obtained. Post hoc comparisons revealed significantly larger SCRs in the presence of fear Journal of Psychophysiology (2018), 32(1), 1–19

Figure 3. Skin conductance responses for the different emotion categories in Experiment 2.

compared to neutral, happy, and relaxing clips (ps < .05). Disgust did not differ from fear clips but did produce larger SCRs than relaxing films (p < .05). Significant differences were also found between films of positive valence. In this case, larger responses were produced by happy compared to relax films (p = .05). Finally, significant differences were found in baseline electrodermal activity between clips of different valence, F(2, 27) = 1,734.98, p < .001, η2 = .99, and content, F(4, 25) = 876.52, p < .001, η2 = .99. Bonferroni-corrected comparisons showed that activity at baseline was significantly different between clips of different valence (ps < .001). However, no significant differences appeared in this measure between films of different emotion content but similar valence. Table 3 shows the mean and standard deviation of SCR levels at baseline for each type of clip. Facial EMG (fEMG) Data from five participants had to be deleted because of excessive movement during the experiment. The final sample consisted of 33 participants (17 females, 16 males). Separate 5 2 2 ANOVAs (Emotion Time Sex) were performed on EMG zygomatic and corrugator activity data. Average responses are shown in Figures 4 and 5. ZM Activity Analysis of ZM activity in the presence of positive (happy and relax clips), neutral and negative clips (fear and disgust) yielded significant effects of Emotion, F(4, 124) = 32.36, p < .001, η2 = .50, Time, F(1, 31) = 6.92, p = .013, η2 = .18, and its interaction, F(4, 124) = 6.69, p < .001, η2 = .18. No significant effects involving Sex were obtained. Happy films produced larger responses than the other film categories at Time 1 and Time 2 (ps < .001). Happy films produced the largest ZM responses at Time 1 and Time 2, followed by disgust, fear, neutral, and relax films. Except in the case of happy films, significant changes in ZM Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Table 3. Mean baseline SCR amplitude according to clip valence and emotion content M

Neutral

2.378

0.006

Positive

2.839

0.013

Negative

2.639

0.027

Neutral

2.378

0.006

Happy

2.834

0.005

Relax

2.844

0.017

Fear

2.646

0.026

Disgust

2.633

0.029

Clip valence

Clip content

Figure 5. EMG activity (corrugator muscle) for the different emotion categories in Experiment 2. t = Time.

Figure 4. EMG activity (zygomaticus muscle) for the different emotion categories in Experiment 2. t = Time.

response appeared along the film’s duration (ps < .05). While ZM activity decreased in the presence of relax, neutral, and fear films, it increased in the presence of disgust films. CS Activity Analysis of the data corresponding to the EMG activity over the CS region gave only a significant main effect of Emotion, F(4, 124) = 8.51, p < .001, η2 = .22. In this case, disgust films produced overall larger responses than happy and relax films (p < .01). More importantly, disgust films produced larger responses than fear (p < .05) films that in turn did not differ from the other categories. Subjective Ratings and Psychophysiological Measures: Correlational Analysis Analysis of the covariation of subjective ratings and electrodermal activity during the stimulus and poststimulus

Ó 2016 Hogrefe Publishing

periods showed a positive correlation between SCR amplitude and arousal, rs = .28 and .24 for the Change Score 1 (during clip) and Change Score 2 (5 s period following stimulus offset), respectively (ps < .01), showing that the clips that were rated as more arousing tended to produce larger SCR changes at both time periods. Arousal ratings also showed a positive correlation with total EMG zygomatic activity, r = .33 (p < .01). Significant negative correlations were found between valence ratings and electrodermal activity at Change Score 1 and Change Score 2, rs = .28 and .29, respectively (ps < .01), showing that clips that received lower valence ratings also tended to produce larger SCR increases. Significant correlations were also shown between fEMG activity and subjective ratings of valence and arousal. A significant negative correlation was found between valence ratings and total EMG corrugator activity, r = .30. Finally, a positive correlation was obtained between arousal ratings and total ZM activity (ps < .01).

Discussion In the present experiment, we report psychophysiological (skin conductance and fEMG) results in response to a selection of a new collection of emotion film clips described in Experiment 1. Moreover, in order to establish the relationship between self-report and psychophysiological results, ratings in the general dimensions of valence and arousal are also presented. Electrodermal activity covaried with perceived arousal in a predictable way. Fear and disgust films that received the highest ratings in arousal also produced larger SCRs. Moreover, happy films received

Journal of Psychophysiology (2018), 32(1), 1–19

higher arousal ratings and produced larger SCRs than relaxing films. The negative correlation obtained between valence and SCR amplitude can be attributed to the specific contents represented in the positive and negative film categories. While the negative category included highly arousing fear and disgust scenes, the positive category included arousing happy scenes and relaxing nature scenes. This explains why positive film clips as a whole tended to produce smaller SCRs than negative ones. Facial EMG activity showed a complex relationship with affective valence, especially in the case of zygomatic responses. Although they were rated as similarly positive, happy films produced larger ZM responses than relax films. In fact, films representing relaxing scenes produced a decrease in ZM activity along clip duration. Somewhat unexpectedly, a significant increase in ZM activity was observed along the duration of disgust films. Disgust films also produced a significant increase in corrugator activity. In contrast, no significant changes in fEMG activity were observed in the presence of fear films. This difference between disgust and fear stimuli is consistent with previous reports that have also shown that corrugator activity differentiates between these two emotional contents (Yartz & Hawk, 2002). The implications of these results are elaborated in more detail in the General Discussion section. We should point out that, in comparison with Experiment 1, the use of a block design is a potential limitation of the present experiment. This design may have produced expectancy effects due to the repetition of clips of similar affective valence on the same block. This might produce either sensitization or habituation effects that might, respectively, lead to increased or decreased psychophysiological reactivity. The use of blocked or randomized presentation in psychophysiological studies is a complex decision as randomized presentation has its own problems, for example due to the presentation of stimuli of opposing valence in adjacent trials that might lead to contrast effects or to the confounding of the effects of the current clip with the post-effects of the previous stimulus of opposing valence. Other differences between Experiments 1 and 2 should be noted. For example, the assessment of valence and arousal was collective in Experiment 1, while it was carried out individually in Experiment 2. Also, the clips were presented in different displays: 12000 projector screen (Experiment 1) versus 2300 LCD monitor (Experiment 2). Therefore, a direct comparison between the mean rating results obtained in Experiments 1 and 2 was computed to check for potential differences between both experiments. Tables 4 and 5 summarize the results of this comparison for the valence and arousal ratings. No statistically significant differences between studies were found in the valence ratings, showing that the different administration conditions did not have an effect on affective ratings. However, Journal of Psychophysiology (2018), 32(1), 1â&#x20AC;&#x201C;19

L. Aguado et al., Responses to Emotional Clips

Table 4. Valence assessment for clips presented in Experiment 1 and Experiment 2 according to different content Valence Experiment 1

Neutral

Experiment 2

Differences

5.24

0.19

5.28

0.21

0.43

0.671

0.22

Happy

7.40

0.29

7.65

0.22

1.04

0.326

0.73

Relax

7.04

0.43

7.14

0.34

0.19

0.851

0.13

Fear

3.04

0.47

2.89

0.50

0.77

0.467

0.63

Disgust

2.90

0.53

2.33

0.27

2.17

0.062

1.53

there were significant differences in the case of the arousal ratings, with the clips in Experiment 2 being rated as more arousing than in Experiment 1. This can be attributed to the presentation procedure used in Experiment 2 that probably increased the emotional impact of the clips. This notwithstanding, it must be said that the rank order of the arousal ratings according to the emotional content of the clips was the same in both experiments, (Relax < Neutral < Happy < Disgust < Fear).

General Discussion The present paper presents evaluative and psychophysiological data on a new collection of emotional film clips. In Experiment 1, rating and self-report results are presented, allowing a characterization of the film collection in terms of both basic affective dimensions and emotion categories. In Experiment 2, we report psychophysiological (skin conductance and fEMG) results in response to a selection of the film clips described in Experiment 1. In this last study, skin conductance results covaried with subjectively perceived arousal in a predictable way, with larger response amplitudes in the presence of more arousing clips. The response of facial musculature, measured through the EMG activity over the zygomaticus and corrugator muscle regions, was sensitive to affective valence and to differences in specific emotion content. The present study is the first to present self-report ratings related to both general affective dimensions (valence and arousal) and emotion category together with psychophysiological measures using short, fixed duration film clips. Apart from the higher realism and emotional impact of dynamic stimuli, the present collection of emotion clips has characteristics that make it appropriate for behavioral and psychophysiological research. Among these, the fixed duration of 10 s for all clips is especially convenient because it reduces the variability introduced by the use of clips of different durations, as has been done in previous research. Moreover, the categorization of the film clips in terms of Ă&#x201C; 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Table 5. Arousal assessment for clips presented in Experiment 1 and Experiment 2 according to different content Arousal Experiment 1 M

Experiment 2 SD

Differences SD

Neutral

2.71

0.57

4.52

0.38

7.76

< .001

3.68

Happy

3.07

0.34

5.41

0.67

6.86

< .001

4.85

Relax

1.90

0.16

2.90

0.36

5.59

.001

3.95

Fear

5.89

0.31

6.73

0.27

4.4

.005

3.59

Disgust

5.32

0.41

6.65

0.14

6.76

< .001

4.78

discrete emotions makes the present collection especially appropriate for the study of subjective and psychophysiological reactions associated to different emotional states. Based on the self-report responses (Experiment 1), we could assign each film clip to one of seven specific emotion categories, happiness, relax, pleasure, anger, fear, disgust, sadness, and neutral. The positive film set included clips that were rated as high (happiness and pleasure) and low (relax) in arousal. This parallels the difference observed between positive arousing and de-arousing pictures in studies with the IAPS collection (e.g., Bradley, Codispoti, Cuthbert, & Lang, 2001; Bradley, Codispoti, Sabatinelli, & Lang, 2001; Ribeiro et al., 2007). In contrast to this, all categories of negative films received high arousal ratings. The absence of negative films rated as low in arousal is consistent with the failure to find a significant number of negative deactivating stimuli in most prior research with emotional stimuli. The categories with less exemplars meeting a predetermined inclusion criterion were pleasure and anger. For example, only one film reached the criterion to be included in the category “anger.” This result is consistent with those of previous studies showing that emotional pictures are not an effective means to elicit anger in the laboratory (e.g., Mikels et al., 2005; Thibodeau, Jorgensen, & Jonovich, 2008) and indicates that film clips are also not effective as anger elicitors (see also Gross & Levenson, 1995). The validity of the emotion categories derived from the participant’s self-report measures in Experiment 1 was partially confirmed by the patterning of autonomic and facial responses in Experiment 2. As expected, electrodermal activity reflected between-category differences in rated arousal. Consistent with these differences participants gave larger SCRs to happy than to relax films. On the other hand, consistent with the lack of differences in rated arousal between fear and disgust films, these two categories elicited similar large SCRs. In contrast to this, the analysis of fEMG data revealed differences between thematic contents that could not be predicted solely on the basis of evaluative ratings of valence and arousal. In the case of positive clips, happy and relaxing scenes had opposed effects. Zygomatic activity was larger in the presence of happy compared to Ó 2016 Hogrefe Publishing

relaxing films. The deactivating effect of relaxing films was shown as a decrease of ZM activity along the clip’s duration. Only negative films representing disgust scenes produced a facial pattern that significantly differed from that observed in the presence of neutral films. Disgust films produced larger corrugator responses than positive films and than those representing fear scenes. Moreover, zygomatic activity increased significantly along the duration of these films. A similar finding has been reported in some studies (Bradley, Codispoti, Cuthbert, & Lang, 2001; de Jong, Peters, & Vanderhallen, 2002) but it is not clear if these responses are part of an exaggerated facial grimace produced by disgusting images (e.g., Burton, 2011) or are due to cross talk from other muscles. The different patterns of psychophysiological response reported in the present study provide a picture of the affective impact of different positive and negative contents that goes beyond what would be expected based only on valence ratings. This confirms the usefulness of film clips to study the patterns of response associated to different emotional states. The differences observed in Experiment 2 between happy and relaxing films partially replicate the results of previous studies with pictures. For example, in Bradley, Codispoti, Cuthbert, and Lang (2001) study, pictures of families with contents similar to those of our “happy” category elicited larger ZM activity than relaxing scenes. However, in that same study, families and nature pictures elicited similar small SCRs. This is in clear contrast with the increase in electrodermal activity observed in our study in the presence of happy clips. On the other hand, smaller SCRs in the presence of both arousing and deactivating positive pictures were observed in a study by Ribeiro et al. (2007). Moreover, in this last study, superior zygomatic activity was observed in response to positive relaxing compared to positive arousing pictures. These differences might be due to the different characteristics of the stimulus materials employed in each study. Of course, one main difference with the present study was the use of static picture stimuli. However, it should be noted that there are important differences in the specific contents included in ours and in each of the previously mentioned studies. For example, in the study by Journal of Psychophysiology (2018), 32(1), 1–19

Ribeiro et al. (2007), the positive arousing category included highly varied contents with or without the presence of human actors (erotic couples, fireworks, nature sports. . .). Similarly, varied contents were included in the positive deactivating category (e.g., babies, couples, nature scenes). In contrast to this, each of the arousing and deactivating categories in our study included more homogeneous contents (babies or animal juveniles in the arousing category and nature scenes in the deactivating category). Thus, it may be that the results obtained by Ribeiro et al. (2007) partly reflect the greater heterogeneity of the contents included in the different picture categories. For example, in that study the positive arousing category included couples in an erotic attitude that tend to produce smaller changes in zygomatic activity (Bernat, Patrick, Benning, & Tellegen, 2006) and can even produce increased corrugator activity, especially in women (Bradley, Codispoti, Sabatinelli, & Lang, 2001). Facial EMG activity differentiated between the two categories of negative clips, fear and disgust, was facial EMG activity. Facial reactivity was, in general, stronger in the presence of disgust films, with increased corrugator activity and a small but significant increase in zygomatic activity. Previous studies have shown that the main characteristic of the facial response to disgusting stimuli is an increase of activity of the levator labii superioris muscle, followed in strength by corrugator activity and sometimes a small increase in zygomatic activity (Bradley, Codispoti, Cuthbert, & Lang, 2001; de Jong et al., 2002; Vrana, 1993). In correspondence with the similar arousal ratings given to fear and disgust films, both elicited similar large SCRs. The results of Experiment 2 revealed that there was a good correspondence between the subjective ratings of the emotion clips and the psychophysiological reactions they elicited. However, when the pattern of skin conductance and fEMG responses is considered, it is also clear that there are variations that go beyond those predicted solely in terms of basic affective dimensions. This was the case of the two categories of negative clips, that is, fear and disgust. These results are relevant for the classic controversy over the specificity of the response patterns associated to different discrete emotions (see Kreibig, 2010; Norman et al., 2014, for recent reviews) and provide new evidence for differentiated response patterns corresponding to different negative emotions that are similarly rated in terms of valence and arousal. A limitation of the study is that a factor of potential relevance, the presence of human interaction in the clips, was not taken into account and controlled for. This might have brought a certain variability both within- and between-categories (e.g., there were more scenes representing human interaction or with human actors in the negative category). We recognize that this is a relevant aspect that Journal of Psychophysiology (2018), 32(1), 1–19

L. Aguado et al., Responses to Emotional Clips

deserves consideration in future research with emotional clips. The combination of self-report and psychophysiological measures in the present study confirms the categorical structure of a new set of emotional films that includes clearly differentiable emotional categories, together with neutral control clips. The results obtained with the electrodermal and facial EMG measures show that psychophysiological responses to emotional stimuli cannot be predicted solely on the basis of general affective dimensions. These results are consistent with previous evidence that the specific thematic content related to different basic emotions is a strong determinant of psychophysiological responding to visual stimuli (e.g., Bernat et al, 2006; Bradley, Codispoti, Cuthbert, & Lang, 2001; Bradley, Codispoti, Sabatinelli, & Lang, 2001; Mikels et al., 2005; Ribeiro et al., 2007) and extends this conclusion to film clips that represent realistic emotional scenes that are closer to the emotional events we experience in daily life.

Acknowledgments This work was supported by the Spanish Ministerio de Economía y Competividad [grant number PSI201344262-P to Luis Aguado]. The participation of Francisco J. Román has been possible thanks to a FPI Grant (PSI2010-20364) from the Spanish Ministerio de Ciencia y Tecnología. Ethics and Disclosure Statements Informed consent was obtained from all participants. All authors disclose no actual or potential conflicts of interest including any financial, personal, or other relationships with other people or organizations that could inappropriately influence (bias) their work.

References Bernat, E., Patrick, C. J., Benning, S. D., & Tellegen, A. (2006). Effects of picture content and intensity on affective physiological response. Psychophysiology, 43, 93–103. doi: 10.1111/j.1469-8986.2006.00380.x Bradley, M. M., Codispoti, M., Cuthbert, B. N., & Lang, P. J. (2001). Emotion and motivation I: Defensive and appetitive reactions in picture processing. Emotion, 1, 276–298. doi: 10.1037/15283542.1.3.276 Bradley, M. M., Codispoti, M., Sabatinelli, D., & Lang, P. J. (2001). Emotion and motivation II: Sex differences in picture processing. Emotion, 1, 300–319. doi: 10.1037/1528-3542.1. 3.300 Bradley, M. M., & Lang, P. J. (1994). Measuring emotion: The selfassessment manikin and the semantic differential. Journal of Behavior Therapy and Experimental Psychiatry, 25, 49–59. doi: 10.1016/0005-7916(94)90063-9

Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Bradley, M. M., & Lang, P. J. (2000a). Measuring emotion: Behavior, feeling, and physiology. Cognitive Neuroscience of Emotion, 25, 49–59. Bradley, M. M., & Lang, P. J. (2000b). Emotion and motivation. Handbook of Psychophysiology, 2, 602–642. Bradley, M. M., & Lang, P. J. (2007). The international affective picture system (IAPS) in the study of emotion and attention. In J. A. Coan & J. J. B. Allen (Eds.), Handbook of emotion elicitation and assessment (pp. 29–46). New York, NY: Oxford University Press. Burton, K. (2011). Habitual emotion regulation and the facial grimace. Psychological Reports, 109, 521–532. doi: 10.2466/ 07.09.21.PR0.109.5.521-532 Cacioppo, J. T., Petty, R. E., Losch, M. E., & Kim, H. S. (1986). Electromyographic activity over facial muscle regions can differentiate the valence and intensity of affective reactions. Journal of Personality and Social Psychology, 50, 260–268. doi: 10.1037/0022-3514.50.2.260 Cacioppo, J. T., Tassinary, L. G., & Berntson, G. (Eds.). (2007). Handbook of psychophysiology. Cambridge, UK: Cambridge University Press. Carvalho, S., Leite, J., Galdo-Álvarez, S., & Gonçalves, Ó. F. (2012). The emotional movie database (EMDB): A self-report and psychophysiological study. Applied Psychophysiology and Biofeedback, 37, 279–294. doi: 10.1007/s10484-012-9201-6 Christie, I. C., & Friedman, B. H. (2004). Autonomic specificity of discrete emotion and dimensions of affective space: A multivariate approach. International Journal of Psychophysiology, 51, 143–153. doi: 10.1016/j.ijpsycho.2003.08.002 Coan, J. A., & Allen, J. J. B. (2007). The handbook of emotion elicitation and assessment. New York, NY: Oxford University Press. de Jong, P. J., Peters, M., & Vanderhallen, I. (2002). Disgust and disgust sensitivity in spider phobia: Facial fEMG in response to spider and oral disgust imagery. Journal of Anxiety Disorders, 16, 477–493. doi: 10.1016/S0887-6185(02)00167-6 Dimberg, U. (1990). Facial electromyography and emotional reactions. Psychophysiology, 27, 481–494. doi: 10.1111/ j.1469-8986.1990.tb01962.x Ekman, P. (1992). An argument for basic emotions. Cognition and Emotion, 6, 169–200. Fernández-Cahill, M. (2012). The face of mixed expressions: Affective ambivalence and expressive ambiguity in facial expressions (Doctoral dissertation). Madrid, Spain: Universidad Complutense de Madrid. Fridlund, A. J., & Cacioppo, J. T. (1986). Guidelines for human electromyographic research. Psychophysiology, 23, 567–589. doi: 10.1111/j.1469-8986.1986.tb00676.x Goldberg, H., Preminger, S., & Malach, R. (2014). The emotionaction link? Naturalistic emotional stimuli preferentially activate the human dorsal visual stream. NeuroImage, 84, 254–264. doi: 10.1016/j.neuroimage.2013.08.032 Greenwald, M. K., Cook, E. W., & Lang, P. J. (1989). Affective judgment and psychophysiological response: Dimensional covariation in the evaluation of pictorial stimuli. Journal of Psychophysiology, 3, 51–64. Gross, J. J., & Levenson, R. W. (1995). Emotion elicitation using films. Cognition and Emotion, 9, 87–108. doi: 10.1080/ 02699939508408966 Haidt, J., McCauley, C., & Rozin, P. (1994). Individual differences in sensitivity to disgust: A scale sampling seven domains of disgust elicitors. Personality and Individual Differences, 16, 701–713. doi: 10.1016/0191-8869(94)90212-7 Hewig, J., Hagemann, D., Seifert, J., Gollwitzer, M., Naumann, E., & Bartussek, D. (2005). A revised film set for the induction of basic emotions. Cognition and Emotion, 19, 1095–1109. doi: 10.1080/02699930541000084

Ó 2016 Hogrefe Publishing

Hubert, W., & de Jong-Meyer, R. (1990). Psychophysiological response patterns to positive and negative film stimuli. Biological Psychology, 31, 73–93. doi: 10.1016/0301-0511(90) 90079-C Izard, C. (1993). Organizational and motivational functions of discrete emotions. In M. Lewis & J. M. Haviland (Eds.), Handbook of emotions (pp. 631–641). New York, NY: Guilford Press. Karama, S., Armony, J., & Beauregard, M. (2011). Film excerpts shown to specifically elicit various affects lead to overlapping activation foci in a large set of symmetrical brain regions in males. PLoS One, 6, e22343. doi: 10.1371/journal. pone.0022343 Kreibig, S. D. (2010). Autonomic nervous system activity in emotion: A review. Biological Psychology, 84, 394–421. doi: 10.1016/j.biopsycho.2010.03.010 Kreibig, S. D., Wilhelm, F. H., Roth, W. T., & Gross, J. J. (2007). Cardiovascular, electrodermal, and respiratory response patterns to fear- and sadness-inducing films. Psychophysiology, 44, 787–806. doi: 10.1111/j.1469-8986.2007.00550.x Lang, P. J., Bradley, M. M., & Cuthbert, B. N. (2008). International affective picture system (IAPS): Affective ratings of pictures and instruction manual. NIMH, Center for the Study of Emotion & Attention. Lang, P. J., Greenwald, M. K., Bradley, M. M., & Hamm, A. O. (1993). Looking at pictures: Affective, facial, visceral, and behavioral reactions. Psychophysiology, 30, 261–273. doi: 10.1111/j.1469-8986.1993.tb03352.x Mauss, I. B., & Robinson, M. D. (2009). Measures of emotion: A review. Cognition and Emotion, 23, 209–237. doi: 10.1080/ 02699930802204677 Mikels, J. A., Fredrickson, B. L., Larkin, G. R., Lindberg, C. M., Maglio, S. J., & Reuter-Lorenz, P. A. (2005). Emotional category data on images from the International Affective Picture System. Behavior Research Methods, 37, 626–630. doi: 10.3758/ BF03192732 Moody, E. J., & McIntosh, D. N. (2011). Mimicry of dynamic emotional and motor-only stimuli. Social Psychological and Personality Science, 2, 679–686. doi: 10.1177/ 1948550611406741 Norman, G. J., Berntson, G. G., & Cacioppo, J. T. (2014). Emotion, somatovisceral afference, and autonomic regulation. Emotion Review, 6, 113–123. doi: 10.1177/1754073913512006 Palomba, D., Sarlo, M., Angrilli, A., Mini, A., & Stegagno, L. (2000). Cardiac responses associated with affective processing of unpleasant film stimuli. International Journal of Psychophysiology, 36, 45–57. doi: 10.1016/S0167-8760(99)00099-9 Philippot, P. (1993). Inducing and assessing differentiated emotion-feeling states in the laboratory. Cognition and Emotion, 7, 171–193. doi: 10.1080/02699939308409183 Ribeiro, R. L., Pompéia, S., & Bueno, O. F. A. (2005). Comparison of Brazilian and American norms for the International Affective Picture System (IAPS). Revista Brasileira de Psiquiatria, 27, 208–215. doi: 10.1590/S1516-44462005000300009 Ribeiro, R. L., Teixeira-Silva, F., Pompéia, S., & Bueno, O. F. (2007). IAPS includes photographs that elicit low-arousal physiological responses in healthy volunteers. Physiology & Behavior, 91, 671–675. doi: 10.1016/j.physbeh.2007.03.031 Rottenberg, J., Ray, R. D., & Gross, J. J. (2007). Emotion elicitation using films. In J. A. Coan & J. J. B. Allen (Eds.), The handbook of emotion elicitation and assessment (pp. 9–28). New York, NY: Oxford University Press. Schaefer, A., Nils, F., Sanchez, X., & Philippot, P. (2010). Assessing the effectiveness of a large database of emotion-eliciting films: A new tool for emotion researchers. Cognition and Emotion, 24, 1153–1172. doi: 10.1080/02699930903274322

Journal of Psychophysiology (2018), 32(1), 1–19

Simons, R. F., Detenber, B. H., Reiss, J. E., & Shults, C. W. (2000). Image motion and context: A between-and within-subjects comparison. Psychophysiology, 37, 706–710. doi: 10.1111/ 1469-8986.3750706 Simons, R. F., Detenber, B. H., Roedema, T. M., & Reiss, J. E. (1999). Emotion processing in three systems: The medium and the message. Psychophysiology, 36, 619–627. Stemmler, G. (2004). Physiological processes during emotion. In P. Philippot & R. S. Feldman (Eds.), The regulation of emotion (pp. 33–70). Mahwah, NJ: Erlbaum. Stephens, C. L., Christie, I. C., & Friedman, B. H. (2010). Autonomic specificity of basic emotions: Evidence from pattern classification and cluster analysis. Biological Psychology, 84, 463–473. doi: 10.1016/j.biopsycho.2010.03.014 Thibodeau, R., Jorgensen, R. S., & Jonovich, S. J. (2008). Anger elicitation using affective pictures: An individual differences approach. Journal of Individual Differences, 29, 80–89. doi: 10.1027/1614-0001.29.2.80 Vrana, S. R. (1993). The psychophysiology of the disgust: Differentiating negative emotional context with facial EMG. Psychophysiology, 30, 279–286. doi: 10.1111/j.1469-8986. 1993.tb03354.x

Journal of Psychophysiology (2018), 32(1), 1–19

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Westermann, R., Spies, K., Stahl, G., & Hesse, F. (1996). Relative effectiveness and validity of mood induction procedures: analysis. European Journal of Social Psychology, 26, 557–580. Yartz, A. R., & Hawk, L. W. Jr. (2002). Addressing the specificity of affective startle modulation: Fear versus disgust. Biological Psychology, 59, 55–68. doi: 10.1016/S0301-0511 (01)00121-1 Received June 3, 2015 Accepted April 27, 2016 Published online November 22, 2016

Luis Aguado Facultad de Psicología Campus de Somosaguas Universidad Complutense de Madrid 28223 Madrid Spain laguadoa@ucm.es

Ó 2016 Hogrefe Publishing

L. Aguado et al., Responses to Emotional Clips

Appendix A Information about the clips presented in Experiment 1 Movie data (name – author – producer – year)

Clip start time* (hh:mm:ss)

Description

Negative clips 11A 11B

11C 11D

11E 11F

11G 11H 11I 11J

12A

12B

12C

12D 12E 12F 12G 12H 12I 12J

Benny’s Video – Michael Haneke – Bernard Lang, Wega Films – 1992 À l’intérieur – Alexandre Bustillo, Julien Maury – Canal+, CinéCinéma, Cofinova 3, Soficinéma 3, Uni Etoile 4, La fabrique de Films, BR Films – 2007 The Three Burials of Melquíades Estrada – Tommy Lee Jones – Europa Corp., Javelina Film Company – 2005 À l’intérieur – Alexandre Bustillo, Julien Maury – Canal+, CinéCinéma, Cofinova 3, Soficinéma 3, Uni Etoile 4, La fabrique de Films, BR Films – 2007 The Three Burials of Melquíades Estrada – Tommy Lee Jones– Europa Corp., Javelina Film Company – 2005 À l’intérieur – Alexandre Bustillo, Julien Maury – Canal+, CinéCinéma, Cofinova 3, Soficinéma 3, Uni Etoile 4, La fabrique de Films, BR Films – 2007 Wild Caribbean (Cap. 3) – BBC Series 4 – British Broadcasting Corporation (BBC) – 2007 Wild Caribbean (Cap. 3) – BBC Series 4 – British Broadcasting Corporation (BBC) 2007 Tiburones. Los ataques más terroríficos del mundo – Discovery Channel – Discovery Communications, Inc. – 2003 Il Mio Nome è Nessuno – Sergio Leone, Tonino Velerii – Riato Film Preben-Philipsen, Les Films Jaques Leitienne, Imp.Ex.Ci., Rafran – 1973 À l’intérieur – Alexandre Bustillo, Julien Maury – Canal+, CinéCinéma, Cofinova 3, Soficinéma 3, Uni Etoile 4, La fabrique de Films, BR Films – 2007 À l’intérieur – Alexandre Bustillo, Julien Maury – Canal+, CinéCinéma, Cofinova 3, Soficinéma 3, Uni Etoile 4, La fabrique de Films, BR Films – 2007 Tiburones. Los ataques más terroríficos del mundo – Discovery Channel – Discovery Channel – Discovery Communications, Inc. – 2003 Saibogujiman kwenchana (I’m A Cyborg, But That’s Ok) – Moho Films – Park Chan-wook–2006 Benny’s Video – Michael Haneke – Bernard Lang, Wega Films – 1992 Insect Wars – National Geographic – National Geographic Society Entertainment – 2003 Insect Wars – National Geographic – National Geographic Society Entertainment – 2003 Insect Wars – National Geographic – National Geographic Society Entertainment – 2003 Insect Wars – National Geographic – National Geographic Society Entertainment – 2003 Science of Babies – Peter Yost – National Geographic Society Entertainment –2006