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In Preparation for Publication

The behavioral study primarily served to obtain independent ratings of social versus non-social emotional stimuli for further use in fMRI experiments N° 2a and 2b. However, as individual AAS scores of all participants could be collected rather easily, it was also analyzed regarding the impact of AX and AV on three different rating scores. Accordingly, the main research question for the behavioral study was:

How does AAS modulate the subjective attribution of likeability, intensity and controllability to positive and negative social versus non-social emotional scenes?

Very few previous studies have assessed the subjective experience of such stimulus properties as likeability (valence), intensity (arousal) or control as a function of AAS. One study [193] reported some effects of AV and AX on subjective experience of the intensity of negative and positive film-clips (see Chapter IV.4.6.), but neither this nor other similar stimulus properties in the context of AAS have systematically been investigated up to date.

The results of the behavioral study showed that AV selectively affected the pleasantness (but not intensity and control) ratings of social positive images: the higher subjects scored on AV, the lower their pleasantness scores to this distinct stimulus category. What is concerning AX, the data revealed higher intensity but lower control ratings for social negative (but not positive) emotional images, but also increased intensity ratings for both positive stimulus categories as a function of high AX. Such rating patterns are consistent with AAT and also previous fMRI findings in the context of this doctoral thesis (see Chapters IV.4.5. and VI.2.), implying decreased positive experience of social positive scenarios by people scoring high on AV, and higher intensity experience but lower control capabilities of social negative scenes by high anxious participants.

What is concerning the findings of higher intensity ratings of both positive emotional image categories as a function of high AX, not as much evidence bolstering such accounts is available.

However, as a central feature of AX is ambivalence, it is possible that people scoring high on AX experience both positive as well as negative (social) scenes as more intense. In any case, more research is needed to clarify particularly the second issue.

Because only AAS scores of the participants were obtained for the behavioral study, the results are not as clear as expected, and no additional measures (i.e. brain correlates) could be collected, these findings were not published yet and currently evaluated if suitable for an ultimate publication.

Nonetheless, they are considered important enough to be an integral part of this doctoral thesis.

The Influence of Adult Attachment Style on the Perception of Social and Non-Social Emotional Scenes

Pascal Vrtička (1,2), David Sander (1,3), & Patrik Vuilleumier (1,2)

(1) Swiss Center for Affective Sciences, University of Geneva

(2) Laboratory for Neurology & Imaging of Cognition, Department of Neurology and Department of Neuroscience, University Hospital and Medical School, University of Geneva

(3) Department of Psychology, FPSE, University of Geneva

ABSTRACT

Attachment theory describes how people emotionally bond with others and how these social interactions are modulated by so called secondary attachment strategies, either involving hyper-vigilance (anxious attachment) or de-activation (avoidant attachment).

However, it still remains unclear whether individual differences in attachment style influence the appraisal of negative and/or attachment-related information only, or whether they may also affect the processing of positive and/or attachment-unrelated content. Thus, it is unknown whether anxious and/or avoidant attachment modulates emotional ratings for negative and positive scenes as a function of their social content. Accordingly, the present study tested how social and non-social positive or negative emotional scenes were subjectively rated on pleasantness, arousal, and control as a function of individual attachment style differences.

Our data revealed that avoidant attachment had a selective impact on pleasantness ratings of social positive images. This finding extends previous literature by showing that attachment style can also have an effect on the subjective experience of positive images, particularly if they contain social information. Moreover, anxious attachment was found to increase intensity but decrease control ratings for social negative images specifically, and lead to higher intensity ratings for both positive stimulus categories. Whereas the former data are supported by attachment theory characterizing anxious attachment with hyper-vigilance to cues of social threat, the latter results could be explained by the notion of ambivalence as a second hallmark of anxious attachment style.

_________________________________________

CORRESPONDING AUTHOR:

Pascal Vrtička

Swiss Center for Affective Sciences

7, rue des Battoirs, 1205 Geneva, Switzerland

Tel: +41 – (0)22 379 9824 Fax: +41 – (0)22 379 9844 Email: pascal.vrticka@unige.ch

INTRODUCTION

Attachment refers to the formation and maintenance of emotional bonds with another person, and is shaped by individual personality factors that reflect one’s needs and expectations concerning social interactions, as well as more general responsiveness to emotionally significant events [1]. Behavioral research in developmental and social psychology has suggested that humans are endowed with a highly organized attachment system which is strongly dependent on early experiences of children with their caregivers, and whose main function throughout life is to maintain proximity to significant others in times of stress, or in other words, to regulate support-seeking behavior [2, 3].

Moreover, because attachment defines lasting feelings of “psychological connectedness between human beings" [2], it is thought to have a tremendous impact on social processes that continues into adulthood [1-3]

and can thus influence how adults perceive and respond to emotional information in a wide range of contexts. Even though the exact links between adult and developmental aspects of the attachment system still remain unresolved [4], it has been proposed that early experiences with primary caregivers during childhood may later give rise to internal working models (IWMs) of the self and others, that become part of a person’s implicit procedural knowledge about socio-affective situations and then govern thoughts, feelings, and behaviors throughout the lifespan [1].

Following the early conception of different attachment patterns in infants [5], researchers have extended attachment theory to adults, and identified four main categories of “attachment styles” that define individual differences in social interactions and emotional responses to others [6]: secure, anxious-preoccupied, dismissive-avoidant, and fearful-avoidant (or disorganized). Individuals with secure attachment (SA) report positive and trustful interactions with others;

whereas attachment anxiety (AX) is characterized by a strong need for closeness, worries about relationships, and fears of rejection; and the hallmarks of attachment avoidance (AV) include a preference for self-reliance and emotional distance from others. More recently, a bi-dimensional theory has been put forward [7-10], in which these different categories of attachment style are mapped on two basic dimensions defined by orthogonal axes of anxiety and avoidance. Thus, in this model, attachment security corresponds to individuals in whom

both anxiety and avoidance are low. A bi-dimensional organization of the attachment system is supported by recent functional brain imaging studies showing that AX correlates with selective increases in the amygdala response to negative social stimuli (angry faces), whereas AV correlates with activation of the ventral striatum and ventral tegmental area to positive social stimuli (smiling faces) [11, 12].

According to the control systems model of the attachment system in adulthood [13], three main modules underlie the functioning of the attachment system. The first module is responsible for the activation of the attachment system through the monitoring and appraisal of signs of social threat. The second module involves the monitoring and appraisal of the availability of an attachment figure, which is closely associated with the sense of felt security. Finally, the third module involves the regulation of proximity-seeking as a way of dealing with perceived attachment insecurity, and operates by either hyperactivating or deactivating strategies to resolve such insecurity.

Whereas hyperactivation of affective response to others is associated with AX, deactivation is related to AV.

Importantly, the control systems model also includes reciprocal influences between modules, such that a recurrent use of hyperactivating or deactivating strategies can affect the appraisal of social threats (first module) and attachment-figure availability (second module). As a consequence, anxiously attached people – who employ hyperactivating strategies and maintain the attachment system in a chronically active state – also tend to exhibit heightened appraisal and enhanced attention towards threatening events. In turn, avoidantly attached people’s tend to use deactivating strategies and maintain their attachment system in a down-regulated or inactive state, which may then lead them to ignore or dismiss threatening events, and to deny the need for an attachment figure availability (for review, see [1]). Moreover, recent neuroimaging data suggest that individual differences in the functioning of the first module might be subtended by changes in brain areas associated with emotional processing, such as the amygdala and ventral striatum [11, 12], whereas differences in the other two modules might implicate prefrontal regions associated with emotional regulation and social conflicts [11, 14] as well as somatosensory areas responsible for emotional contagion and recognition [15].

In the present study, we specifically investigated emotional processes linked to the first module of the control systems model, and tested whether individual differences in attachment system activation might influence the appraisal of emotional information with or without social significance.

According to attachment theory, the attachment system is activated only in threatening conditions, but the triggering events could be either attachment-related (e.g., the loss of a loved one) or attachment-unrelated (e.g., receiving a frightening medical diagnosis). This has been found in particular for hyperactivating or deactivating strategies linked to an anxious or avoidant attachment style, respectively, because even attachment-unrelated distress-eliciting material may reactivate representations and needs for social proximity and protection [13, 16, 17]. However, despite abundant research on attachment system activation in social conditions, very few studies have directly investigated the monitoring and processing of more general emotional material. In particular, it still remains

unclear whether individual differences in attachment style influence the appraisal of negative and/or attachment-related information only, or whether they may also affect the processing of positive and/or attachment-unrelated content. Moreover, although recent brain imaging results have shown that attachment style correlates with differential responses of emotional brain areas to faces [11, 15] and sentences with attachment-related meaning [12, 14], it remains unknown whether these findings would extend to other (non social) material, and whether they may translate into behavioral differences in subjective emotional judgments. Here, we therefore examined how individual attachment style influences emotional ratings for negative and positive scenes as a function of their social content.

Previous behavioral studies investigating emotional processes in relation to attachment have generally focused on either vigilance or attentional monitoring for verbal material or emotional facial expressions. For instance, a study by Mikulincer et al.

[18] showed that highly anxious people were faster to make lexical decisions in response to the names of their attachment figures. In another study by Fraley et al.

[19], highly anxious subjects perceived the onset as well as the offset of emotional facial expressions in a morph movie paradigm at earlier time-points relative to people with secure attachment. However, no specific patterns could be found for avoidant people, and no data was collected on attachment-unrelated cues in neither of these studies. Other studies on attentive processing using a classic dot-probe paradigm [20, 21]

reported that attachment anxiety was associated with a selective hypervigilance toward attachment names, while both attachment anxiety and avoidance were associated with an attentional bias away from general threat-related words. However, in fact, the best predictor for this attentional aversion was the interaction between attachment anxiety and avoidance. These results confirm that attentional processing may differ as a function of secure (low anxious and low avoidant) versus insecure (high anxious and high avoidant) attachment [22, 23], but these effects could result from differential responsiveness at either the appraisal or regulatory stages in the control systems model of attachment [1]. Moreover, attention may be automatically captured by threat-related stimuli in the absence of negative evaluation in explicit or implicit emotional judgments [24]. Therefore, these previous behavioral results did not disentangle the influence of specific attachment dimensions, i.e. anxiety or avoidance, on the subjective appraisal of emotional information. Only one recent study using emotional video-clips with attachment-related content [25] showed that anxious individuals experienced negative emotions of fear and sadness as more arousing as compared with secure individuals, whereas avoidant individuals experienced positive emotions as less arousing than the other two groups. Although this study provides new clues about the effect of attachment system activation on emotional appraisal, it did not distinguish between responses to attachment-related and -unrelated image content.

The goal of our study was to obtain measures that were sensitive to both avoidance and anxiety, and to investigate their influence on the appraisal of more general emotional cues, by using visual scenes with both attachment-related and unrelated content (i.e.

social vs non-social), and both positive and negative

emotional significance. For this purpose, we asked participants to rate different visual scenes on three standard rating scales, widely used in the field of emotion research [26], which assessed the appraisal of pleasantness, arousal, and control. This enabled us to measure not only the perceptual and relatively automatic aspects of emotion processing (pleasantness and arousal), but also the more cognitive and regulatory aspects (control) that might be modulated by different patterns of attachment system activation during affective appraisals. Importantly, our stimuli made no explicit reference to particular attachment figures (e.g.

parents, romantic partners…) or specific attachment concepts (e.g. love, trust...), but rather probed for any effect reflecting an implicit (or unconscious) activation of attachment system when processing general emotional scenes.

METHODS SUBJECTS

We recruited 57 participants from second-year psychology students at Geneva University (average age 23.57 years, 55 female). Only women were included in the final analysis to ensure homogenous effects without gender-related differences, because of evidence that emotions are typically more intense and more prone to regulation in women (e.g. [27]). In addition, data from one female subject was removed at a later step because of incoherent response pattern (see Stimuli and Rating). Therefore, data from 54 subjects (all female) were included in the final analysis.

ATTACHMENT QUESTIONNAIRE

Individual attachment style was assessed in all subjects using a French version of the Relationship Scale Questionnaire (RSQ; [28], translated and validated in previous work by N. Guédeney (2005).

Following recent recommendations in a review paper by Kurdek et al. [8], the RSQ was analyzed according to a specific dimensional model of attachment [10], by calculating two separate scores for AVOIDANCE (AV) and ANXIETY (AX) for each subject, based on 13 items (8 for AV and 5 for AX) out of the total 30 items in the questionnaire. Values were then centered (z-scores) to reduce effects of multicollinearity [29].

STIMULI and RATING

We created a set of 360 emotional pictures that were chosen either from the International Affective Pictures System (IAPS) [30] or from images on the internet, and then sorted according to a 2x2 factorial design, with SCENE CONTENT (SC; either social or non-social, i.e. attachment-related or -unrelated) and VALENCE (VAL; either positive or negative) as factors.

This gave rise to four different experimental categories:

Social Positive (SP) or Negative (SN) scenes, plus Non-Social Positive (NSP) or Negative (NSN) scenes.

Pictures belonging to the social category displayed scenes with a clear social implication mostly depicting two or more individuals, such as two people fighting (negative VAL), or a mother interacting with her baby (positive VAL). In contrast, images belonging to the non-social category depicted scenarios with no people directly involved, like a dead bird covered in oil (negative VAL), or a tropical island scene (positive VAL).

All pictures were in colors and appropriately adjusted to obtain similar low-level properties (e.g. size, luminance, and pixel resolution).

From the entire image set, two separate lists of 180 pictures were generated, each including 45 pictures per experimental category. Subjects had to rate all emotional pictures from one list in two sessions, each lasting approximately 15 minutes. Each picture was presented on a computer screen for 3 seconds, and followed by a rating screen that remained visible until a response was made. An empty interval of **

seconds preceded the onset of the next picture. Ratings were made using a continuous scale (from 0 to 100) for three different dimensions [26]: PLEASANTNESS (PLN; from “very negative” to “very positive”), INTENSITY (INT; from “low arousal” to “high arousal”), and CONTROL (CON; “To what extent were you able to control the induction of emotion by the previous picture?”, from “absence of control” to “presence of control”). Since there were no significant differences between rating scores for PLN, INT, and CON between the two lists, our subsequent analysis pooled the rating responses across all 360 emotional pictures and all subjects without keeping this list factor.

By inspecting the raw data, we noticed that one female subject showed abnormal rating scores on the pleasantness scale (with only a small and negative difference between pleasant and unpleasant pictures [mean -1.66 ± 1.09], unlike the large and positive followed by partial correlations using individual indices for the different dimensions of attachment style (AV, AX).

RESULTS

Relationships scales questionnaire (RSQ)

The mean scores for each attachment dimension across all participants were 19.08 ± 4.97 for AV and 10.96 ± 3.92 for AX. This corresponds to previous findings for a healthy unselected population [8].

There was a mild positive association PLEASANTNESS rating

We first computed a 2x2 repeated measures analysis of variance (ANOVA) on pleasantness ratings, with VAL and SC as factors, across all participants.

Only a significant man effect of VAL [F(1,53)= 5958, p<

0.001], because positive images were rated significantly more pleasant than negative images (Figure 1a) – as expected. There was no main effect of SC [F(1,53)=

1.21, p= .277] and no interaction [F(1,53)= 2.38, p= .121], indicating that our image set was successfully balanced in valence across the different scene contents.

Next, we computed the bivariate correlations between PLN ratings and the different attachment style indices.

This analysis revealed a specific negative correlation between the PLN ratings for social positive (SP) images and avoidant attachment style [AV; Pearson r= -.292, p= .032] (Figure 1b). In other words,

Figure 1: a) Main effect of picture valence on the pleasantness ratings, showing that positive images were rated as more pleasant than negative images. b) Significant negative correlation between avoidance scores and pleasantness ratings for social positive images.

the higher subjects scored on AV, the less pleasant they specifically rated the SP images. In contrast, there were no significant correlations between AV and the PLN ratings for the three remaining image categories [Pearson-rs< ± 0.185, ps> .181]. Likewise, no significant correlations were found between AX and PLN ratings for any of the image categories [Pearson -rs< ± 0.151, ps> .276]. Finally, to ensure that the found negative correlation between PLN ratings for SP images and AV was independent of AX, we computed an additional partial correlation, which remained significant even if controlling for AX [r= -.289, p= .036].

INTENSITY rating

As above, a 2x2 repeated measures ANOVA was first computed across all participants. This analysis revealed (1) a main effect of VAL [F(1,53)= 1.474E2, p<

0.001], because negative images were rated as more intense than positive images; (2) a main effect of SC [F(1,53)= 8.376, p= .006], because social images were rated as more intense than non-social images; and (3) a significant interaction between VAL x SC [F(1,53)=

11.138, p= .002], because the difference in intensity ratings between social and non-social images was present only for positive stimuli [t(54,1)= 3.45, p= .001;

paired t-test], but not for negative stimuli [t(54,1)= .27, p= .79] (Figure 2a).

The bivariate correlations between INT ratings and attachment indices showed (marginally) significant effects for the anxious dimension only. That is, the higher subjects scored on anxiety (AX), the more intense they rated the two categories of positive images [SP: Pearson r= .262, p= .056; NSP: Pearson r= .30,

p= .028], and the more intense they rated the social negative images [SN; Pearson r= .272, p= .047] (Figure 2b). There was no significant correlation between AX scores and INT ratings for NSN images [Pearson-r= .204, p= .138]. Similarly, no correlations were found

p= .028], and the more intense they rated the social negative images [SN; Pearson r= .272, p= .047] (Figure 2b). There was no significant correlation between AX scores and INT ratings for NSN images [Pearson-r= .204, p= .138]. Similarly, no correlations were found