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Adult attachment style and social anhedonia in healthy volunteers
Personality and Individual Differences 48 (2010) 640–643
Contents lists available at ScienceDirect
Personality and Individual Differences journal homepage: www.elsevier.com/locate/paid
Adult attachment style and social anhedonia in healthy volunteers Alfonso Troisi *, Stefano Alcini, Mariangela Coviello, Roberta Croce Nanni, Alberto Siracusano Department of Neuroscience, University of Rome Tor Vergata, Rome, Italy
a r t i c l e
i n f o
Article history: Received 9 November 2009 Received in revised form 4 January 2010 Accepted 7 January 2010 Available online 29 January 2010 Keywords: Social anhedonia Attachment style Avoidant attachment ASQ SHAPS
a b s t r a c t Several studies that have explored associations between attachment measures and interpersonal dispositions have found that people with avoidant attachment consistently express a preference for being alone rather than affiliating with others. These findings suggest that the lack of sociability of avoidant individuals reflects high levels of social anhedonia. We tested such a hypothesis by administering the Attachment Style Questionnaire (ASQ) and the social anhedonia subscale of the Snaith–Hamilton Pleasure Scale (SHAPS) to 163 healthy volunteers. Social anhedonia was not related to gender, age or current mood state, as measured by the Profile of Mood States (POMS). In a stepwise regression model, the confidence and the discomfort with closeness scales of the ASQ emerged as significant predictors of the SHAPS social score, indicating that higher levels of social anhedonia were associated with avoidant attachment but not with anxious attachment. These findings raise interesting questions about the causal link between avoidant attachment and social anhedonia. It is possible that the construct of avoidant attachment as measured by self-report measures includes a heterogeneous group of individuals and that some have a basic deficit in the capacity to experience social reward rather than a defensive deactivation of intimacy needs. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Anhedonia (i.e., a diminished capacity to experience pleasure) is considered a major symptom of different psychiatric disorders. Since the writings of Bleuler and Kraepelin, anhedonia has figured in clinical descriptions of the core deficits of schizophrenia and it is still listed by many authors among the negative symptoms of the schizophrenia-spectrum disorders (Pelizza & Ferrari, 2009). Anhedonia also appears to be a particularly central feature of major depression, especially of the melancholic subtype (Stein, 2008). Social anhedonia, defined as a reduced capacity to experience pleasure and reward from social affiliation, not only has clinical implications, but also appears to be an identifiable personality trait that characterizes many people without diagnosable psychiatric disorders (Brown, Silvia, Myin-Germeys, & Kwapil, 2007; Harvey, Pruessner, Czechowska, & Lepage, 2007). The origin of individual differences in the capacity to experience social reward is likely to involve a complex interplay of genetic and environmental variables, including genetic variation, early experience and current situational factors. A personality variable that may be related to individual differences in social hedonic capacity is adult attachment style. The original focus of attachment theorists was the mother–child
* Corresponding author. Address: Department of Neuroscience, University of Rome Tor Vergata, via Guattani 14, 00161 Rome, Italy. Tel.: +39 06 4423 2998. E-mail address: [email protected] (A. Troisi). 0191-8869/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.paid.2010.01.002
relationship, but in recent years, there has been a considerable increase in both clinical and research interest in the field of adult attachment (Mikulincer & Shaver, 2007). Adult attachment theory is an extension of Bowlby and Ainsworth’s attachment theory, designed to explain individual differences in cognitions, feelings, and behaviors that occur in the context of adolescent and adult close relationships. There are two dimensions of insecurity underlying all self-report measures of adult attachment. The first dimension, attachment-related anxiety, is concerned with a strong desire for closeness and protection, intense worries about abandonment, and use of hyperactivating strategies to deal with attachment-related distress. The second dimension, attachment-related avoidance, is concerned with discomfort with closeness, preference for emotional distance and self-reliance, and use of deactivating strategies to deal with attachment-related distress. Attachment style is associated with various aspects of interpersonal regulation (i.e., the processes that regulate a person’s interactions with others) and influences people’s feelings, thoughts, attitudes, and behaviors in social interactions. Several studies that have explored associations between attachment measures and interpersonal dispositions have described people with avoidant attachment as somewhat introverted, cold, and emotionally inexpressive (Cyranowski et al., 2002; Duggan & Brennan, 1994). Avoidant individuals consistently express a preference for being alone rather than affiliating with others (Shaver et al., 1996). These findings suggest that the lack of sociability typical of avoidant people reflects high levels of social anhedonia. Yet, to our knowledge,
A. Troisi et al. / Personality and Individual Differences 48 (2010) 640–643
no study has directly tested such a hypothesis by measuring simultaneously adult attachment style and social anhedonia. In this study, we measured individual differences in social hedonic capacity and analyzed their correlations with a dimensional measure of adult attachment style in a relatively large sample of healthy volunteers. We hypothesized that avoidant attachment, but not anxious attachment, was positively correlated with higher levels of social anhedonia. Studying the relationship between attachment and social anhedonia is important to clarify the developmental pathways leading to and originating from social withdrawal (Rubin, Coplan, & Bowker, 2009). Since a deficit in the experience of social pleasure is a major risk factor for different psychiatric disorders (Watson & Naragon-Gainey, in press), the identification of developmental factors associated with social anhedonia may enable high risk populations to be delineated. 2. Method 2.1. Participants Data reported here were collected as a part of a larger study aimed at investigating the personality correlates of adult attachment styles. One hundred and sixty three healthy volunteers (mean age: 29.3 ± 9.3 years; range: 19–67 years) were recruited among students in the medical school, paramedic staff members, and conscripts of the Italian army. Participants with personality disorders and/or psychiatric disorders were screened out of the protocol. Exclusion from the sample was based on the presence of a DSM-IV diagnosis, not on the scores of psychometric instruments administered to participants. Diagnostic assessment was made by experienced clinical psychiatrists using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-CV) (First, Gibbon, Spitzer, & Williams, 1997) and the Schedule for Interviewing DSM-IV Personality Disorders-IV (SIDP-IV) (Pfohl, Blum, & Zimmerman, 1997). The University Intramural Ethical Committee approved all procedures and protocols, and written informed consent was obtained before enrollment. All the participants were blind to the aims of the study. 2.2. Psychometric assessment The social anhedonia subscale of the Snaith–Hamilton Pleasure Scale (SHAPS; Snaith et al., 1995) was used to measure the capacity to experience pleasure in social situations. The SHAPS is a 14-item questionnaire instructing participants to agree or disagree with statements of hedonic response in pleasurable situations. Each of the items has a set of four response categories ranging from 1 (definitely agree) to 4 (definitely disagree). A higher total score indicates higher levels of anhedonia. This scale has shown adequate overall psychometric properties in clinical and student samples (Franken, Rassin, & Muris, 2007; Gilbert, Allan, Brough, Melley, & Miles, 2002). The SHAPS covers four domains of hedonic experience: interest/pastimes, social interaction, sensory experience, and food/drink. The social anhedonia subscale (SHAPS–SOC) includes statements such as ‘‘I would enjoy being with family or close friends” and ‘‘I would enjoy seeing other people’s smiling faces.” Participants were instructed to compile the SHAPS to describe their habitual hedonic responses, not their experiences in the last few days. The Attachment Style Questionnaire (ASQ; Feeney, Noller, & Hanrahan, 1994) was used to measure adult attachment style. The ASQ is a 40-item self-report questionnaire with individual items being scored on a six-point scale from 1 (totally disagree) to 6 (totally agree). The ASQ refers to all close relationships with
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peers (whether romantic or not) and includes five subscales derived from principal-components analysis: confidence (in self and others), discomfort with closeness, Need for Approval, Preoccupation with Relationships, and Relationships as Secondary (to achievement). The five scales of the ASQ have been shown to have adequate internal consistency, with Cronbach’s a coefficients ranging from 0.76 to 0.84 and 10-week retest reliability coefficients ranging from 0.67 to 0.78 (Feeney et al., 1994). The confidence subscale is a general measure of the security of attachment. The Need for Approval and the Preoccupation with Relationships subscales assess the anxiety (about abandonment) dimension of the attachment style, whereas the discomfort with closeness and the Relationships as Secondary subscales pertain primarily to the avoidance (of intimacy) dimension of the attachment style. Individuals scoring highly on attachment-related anxiety endorse statements such as ‘‘I find that others are reluctant to get as close as I would like” and ‘‘It’s important to me that others like me”. Individuals scoring highly on attachment-related avoidance endorse statements such as ‘‘My relationships with others are generally superficial” and ‘‘Achieving things is more important than building relationships”. To control for the confounding effect of current mood on the assessment of attachment and social anhedonia, participants were asked to compile the Profile of Mood States (POMS; McNair, Lorr, & Droppleman, 1992). They were asked to carefully read each of 65 items, then respond to a five-point Likert scale ranging from 1 (not at all) to 5 (extremely) based on how they were feeling the day they completed the inventory. The total mood disturbance score (POMS–TMD) was calculated by summation of the five negative affect scales (fatigue, depression, tension, anger, and confusion) and subtraction of the vigor scale. A higher POMS–TMD corresponds to higher levels of mood disturbance. 2.3. Statistical analysis Comparisons between men and women were performed using t test. Pearson coefficients of correlation (r) were used to calculate bivariate correlations between variables. Stepwise regression analysis was used to identify the significant predictors of the SHAPS– SOC score. Collinearity diagnostics based on eigenvalues of the scaled and uncentered cross-products matrix, variation inflation factors (VIF) and tolerances for individual variables were used to exclude multicollinearity among the independent variables. Analysis was performed on a personal computer using SPSS for Windows, version 17.0 (SPSS, Inc., Chicago, Ill). 3. Results Preliminary analyses aimed at ascertaining whether social anhedonia was related to gender, age or mood state. None of these variables were related to the SHAPS–SOC score, as shown by the non-significant difference between men and women (t = 0.73, df = 161, NS) and by the non-significant correlations with age (r = 0.08, NS) and POMS–TMD score (r = 0.10, NS). The results did not change when the sample was stratified by gender (Table 1). Thus, we could exclude that associations between social anhedonia and adult attachment styles were due to the confounding effects of gender, age or mood state. We found significant bivariate correlations between the SHAPS– SOC score and two scales of the ASQ (Confidence and Discomfort with Closeness) (Table 1). Higher levels of attachment insecurity corresponded to higher levels of social anhedonia. To clarify which dimensions of insecure attachment were the best predictors of social anhedonia, we next fit a stepwise regression model with the SHAPS–SOC score as the dependent variable and the five ASQ
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A. Troisi et al. / Personality and Individual Differences 48 (2010) 640–643
Table 1 Bivariate correlations between social anhedonia and age, mood state, and attachment ratings for the participants divided by gender.
Age POMS–TMD ASQ CON ASQ DIS ASQ RAS ASQ PRE ASQ NFA
Women (N = 110)
Men (N = 53)
r = 0.01 r = 0.17 r = 0.25** r = 0.22* r = 0.18 r = 0.07 r = 0.06
r = 0.19 r = 0.05 r = 0.21 r = 0.27* r = 0.16 r = 0.03 r = 0.21
POMS–TMD, total mood disturbance score of the Profile of Mood States; ASQ, Attachment Style Questionnaire; ASQ CON, confidence scale; ASQ DIS, discomfort with closeness scale; ASQ RAS, Relationships as Secondary scale; ASQ PRE, Preoccupation with Relationships scale; ASQ NFA, Need for Approval scale. * P < 0.05. ** P < 0.01.
scales as the independent variables. The resulting equation was significant (F = 7.13, df = 2, 160, P < 0.001) and explained 8.2% (R2) of the variance in the SHAPS–SOC score. The Confidence and the Discomfort with Closeness scales emerged as significant predictors of the SHAPS–SOC score, indicating that, among the healthy participants of this study, higher levels of social anhedonia were associated with avoidant attachment but not with anxious attachment (Table 2). 4. Discussion Confirming the hypothesis of the study, we found that, compared with participants with a secure style of adult attachment, participants with insecure attachment experienced less pleasure and reward from social affiliative interactions. The dimension of insecure attachment that was correlated with social anhedonia was avoidance but not anxiety. To our knowledge, no previous study has directly investigated the relationship between adult attachment and social hedonic capacity by using a psychometric scale designed to measure social anhedonia. Thus, our findings are not comparable with others in the literature. However, in line with the results of the present study, several studies focusing on adult attachment and the process of interpersonal regulation have documented a specific relationship between attachments and selfreport of diminished interest in social interactions. Diary techniques have been used to study how people react to daily interactions with different kinds of relationship partners (Kafetsios & Nezlek, 2002; Pierce & Lydon, 2001; Pietromonaco & Barrett, 1997; Tidwell, Reis, & Shaver, 1996). Despite methodological differences in the assessment of attachment, these studies have consistently shown that, compared with secure people, avoidant individuals experience a lack of engagement in social interactions, which leads them to feel bored and distant. In addition, they tend to report lower levels of satisfaction, intimacy, self-disclosure, supportive behavior, and positive emotions during daily interactions. In contrast, anxious people are similar to secure ones in their reports of intimacy and satisfaction but different in reports of higher negative emotions and feelings of rejection, especially when interacting with opposite-sex partners.
Table 2 Stepwise regression analysis: ASQ scales as predictors of social anhedonia. B Constant ASQ CON ASQ DIS
SE B 6.05 0.06 0.04
ASQ, Attachment Style Questionnaire; R2 = 0.08. * P < 0.05.
1.26 0.03 0.02
b 0.18* 0.17*
It is worth noting that, in our study, adult attachment style explained only a small portion (8.2%) of the variance in social anhedonia. This is not surprising considering that individual differences in the capacity to experience social reward are likely to involve a complex interplay of genetic and environmental variables, including genetic variation, early experience and current situational factors. However, another factor that may explain the weak relationship between attachment and social anhedonia is the composition of our sample. We screened out individuals with DSM-IV Axis I or Axis II disorders and studied a very healthy sample. It is possible that in clinical samples including patients with psychiatric disorders and/or personality disorders associated with high levels of social anhedonia and attachment insecurity, the statistical correlations between these variables are substantially stronger. Future studies should test such a hypothesis by focusing on those mental and behavioral disorders that present anhedonia as a core psychopathological symptom, including major depression, negative schizophrenia, substance use disorder, and eating disorders. Our findings raise interesting questions about the causal link between avoidant attachment and social anhedonia. According to attachment researchers, avoidant people steer clear of intimate exchanges that might facilitate attachment formation because they have negative expectations and are vulnerable to rejection (Bartholomew, 1990; Fraley, Davis, & Shaver, 1998). Based on this view, the social anhedonia of avoidant individuals would be a defense against attachment-related distress rather than a primary deficit in the capacity to experience pleasure and reward from social affiliation. We agree that it is possible for some people to defensively report that they are not rewarded by social interactions, when actually they are rewarded, and for some not to have conscious access to their desire for intimate relationships even though such a desire exists. Partial support for this interpretation comes from our finding that not only the ASQ scale measuring avoidant attachment but also the scale measuring attachment insecurity was correlated with social anhedonia. However, an alternative interpretation is that the construct of avoidant attachment as measured by self-report scales includes a heterogeneous group of individuals and that some have a basic deficit in the capacity to experience social reward rather than a defensive deactivation of intimacy needs. If this is the case, then avoidant attachment is secondary to social anhedonia. Such a hypothesis would imply a basic dysfunction in the neural circuitry that modulates social hedonic responses rather than ‘‘learned” anhedonia caused by negative attachment experiences in early infancy and childhood (e.g., unrewarding interactions with unresponsive caregivers). In line with this alternative interpretation, we found that social anhedonia did not correlate with either of the two scales of the ASQ that reflect anxiety about abandonment and rejection. In addition, there was no correlation between social anhedonia and negative affect, as measured by the POMS. Translated into the language of attachment research, this means that social anhedonia seems to be related more with dismissing-avoidant attachment than fearfulavoidant attachment. There are important differences between fearful and dismissing individuals, although both share a detached stance toward others. Fearful individuals have negative self-models which are reflected in high emotional dependence, high jealousy, and high separation anxiety. Their avoidance of intimacy is due to fear of rejection. In contrast, dismissing individuals have a positive self-model. They have a moderate to high sense of selfconfidence. These individuals downplay the importance of relationships, stress the importance of emotional independence and tend neither to be jealous nor to be anxious when separated from significant others. They maintain an emotional distance from others because they are uncomfortable with affection and do not like other people very much (Bartholomew & Shaver, 1998).
A. Troisi et al. / Personality and Individual Differences 48 (2010) 640–643
Similar findings have been reported by a recent study using experience-sampling methodology to explore deviations in social attachment (or ‘‘the need to belong” in the authors’ terminology) in the daily lives of 245 undergraduates (Brown et al., 2007). Higher levels of social anhedonia were associated with increased time alone, greater preference for solitude, and lower positive affect. Higher social anxiety, in contrast, was associated with higher negative affect and was not associated with increased time alone. The authors concluded that deviations in the need to belong affect social functioning differently depending on whether this need is absent or thwarted. Neurobiological research has also provided preliminary evidence that avoidant attachment can reflect a diminished capacity to experience pleasure from social contact which is largely independent from fears of rejection. Using functional magnetic resonance imaging (fMRI) in healthy volunteers, Vrticˇka, Andersson, Grandjean, Sander, and Vuilleumier (2008) examined how adult attachment styles modulate brain responses to facial expressions conveying either positive or negative feedback about task performance in a social game context. They found that, in response to positive feedback signaled by a smiling face, participants with avoidant attachment showed lower activation in brain regions linked to social reward, including both ventral striatum and ventral tegmental area. Their relative impassiveness to social reward was independent from sensitivity to social punishment, an emotional trait characteristic of participants with anxious attachment and reflected by an increased left amygdala response to signals of social reproach. This study has three major limitations. First, screening out people with psychiatric disorders, we excluded participants with extreme scores and reduced the power of statistical analysis. However, because there were no previous studies of the relationship between adult attachment and anhedonia, we decided to study healthy subjects to increase the generalizability of our preliminary findings. Second, we used self-report scales. Although there is evidence that self-report measures of attachment (Mikulincer & Shaver, 2007) and social anhedonia (Kwapil et al., 2009) are predictably related to interpersonal behavior, future studies aimed at replicating our findings should combine self-report measures with direct observation of attachment behavior and hedonic responses in natural social contexts and experimental settings. Third, we did not collect data about participants’ early experiences. These retrospective data would be useful to ascertain to what extent social anhedonia is secondary to negative attachment experiences with primary caregivers. 5. Conclusions The present study is an initial step in analyzing the relationship between attachment style and social hedonic capacity and addresses a small fraction of the theoretical questions that can be explored in future studies. To resolve the ambiguity that complicates the interpretation of causal links, we need to integrate the great deal of knowledge about the cognitive, emotional, and behavioral correlates of attachment styles with the recent findings of genetic (Ebstein et al., 2009; Israel et al., 2008) and neurobiological studies (Heinrichs & Domes, 2008) of social attachment and affiliative behavior. Acknowledgments We are grateful to Giorgio Di Lorenzo, Luca Proietti and Elena Battellocchi for assistance with the larger study of which this is one part.
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Contents lists available at ScienceDirect
Personality and Individual Differences journal homepage: www.elsevier.com/locate/paid
Adult attachment style and social anhedonia in healthy volunteers Alfonso Troisi *, Stefano Alcini, Mariangela Coviello, Roberta Croce Nanni, Alberto Siracusano Department of Neuroscience, University of Rome Tor Vergata, Rome, Italy
a r t i c l e
i n f o
Article history: Received 9 November 2009 Received in revised form 4 January 2010 Accepted 7 January 2010 Available online 29 January 2010 Keywords: Social anhedonia Attachment style Avoidant attachment ASQ SHAPS
a b s t r a c t Several studies that have explored associations between attachment measures and interpersonal dispositions have found that people with avoidant attachment consistently express a preference for being alone rather than affiliating with others. These findings suggest that the lack of sociability of avoidant individuals reflects high levels of social anhedonia. We tested such a hypothesis by administering the Attachment Style Questionnaire (ASQ) and the social anhedonia subscale of the Snaith–Hamilton Pleasure Scale (SHAPS) to 163 healthy volunteers. Social anhedonia was not related to gender, age or current mood state, as measured by the Profile of Mood States (POMS). In a stepwise regression model, the confidence and the discomfort with closeness scales of the ASQ emerged as significant predictors of the SHAPS social score, indicating that higher levels of social anhedonia were associated with avoidant attachment but not with anxious attachment. These findings raise interesting questions about the causal link between avoidant attachment and social anhedonia. It is possible that the construct of avoidant attachment as measured by self-report measures includes a heterogeneous group of individuals and that some have a basic deficit in the capacity to experience social reward rather than a defensive deactivation of intimacy needs. Ó 2010 Elsevier Ltd. All rights reserved.
1. Introduction Anhedonia (i.e., a diminished capacity to experience pleasure) is considered a major symptom of different psychiatric disorders. Since the writings of Bleuler and Kraepelin, anhedonia has figured in clinical descriptions of the core deficits of schizophrenia and it is still listed by many authors among the negative symptoms of the schizophrenia-spectrum disorders (Pelizza & Ferrari, 2009). Anhedonia also appears to be a particularly central feature of major depression, especially of the melancholic subtype (Stein, 2008). Social anhedonia, defined as a reduced capacity to experience pleasure and reward from social affiliation, not only has clinical implications, but also appears to be an identifiable personality trait that characterizes many people without diagnosable psychiatric disorders (Brown, Silvia, Myin-Germeys, & Kwapil, 2007; Harvey, Pruessner, Czechowska, & Lepage, 2007). The origin of individual differences in the capacity to experience social reward is likely to involve a complex interplay of genetic and environmental variables, including genetic variation, early experience and current situational factors. A personality variable that may be related to individual differences in social hedonic capacity is adult attachment style. The original focus of attachment theorists was the mother–child
* Corresponding author. Address: Department of Neuroscience, University of Rome Tor Vergata, via Guattani 14, 00161 Rome, Italy. Tel.: +39 06 4423 2998. E-mail address: [email protected] (A. Troisi). 0191-8869/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.paid.2010.01.002
relationship, but in recent years, there has been a considerable increase in both clinical and research interest in the field of adult attachment (Mikulincer & Shaver, 2007). Adult attachment theory is an extension of Bowlby and Ainsworth’s attachment theory, designed to explain individual differences in cognitions, feelings, and behaviors that occur in the context of adolescent and adult close relationships. There are two dimensions of insecurity underlying all self-report measures of adult attachment. The first dimension, attachment-related anxiety, is concerned with a strong desire for closeness and protection, intense worries about abandonment, and use of hyperactivating strategies to deal with attachment-related distress. The second dimension, attachment-related avoidance, is concerned with discomfort with closeness, preference for emotional distance and self-reliance, and use of deactivating strategies to deal with attachment-related distress. Attachment style is associated with various aspects of interpersonal regulation (i.e., the processes that regulate a person’s interactions with others) and influences people’s feelings, thoughts, attitudes, and behaviors in social interactions. Several studies that have explored associations between attachment measures and interpersonal dispositions have described people with avoidant attachment as somewhat introverted, cold, and emotionally inexpressive (Cyranowski et al., 2002; Duggan & Brennan, 1994). Avoidant individuals consistently express a preference for being alone rather than affiliating with others (Shaver et al., 1996). These findings suggest that the lack of sociability typical of avoidant people reflects high levels of social anhedonia. Yet, to our knowledge,
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no study has directly tested such a hypothesis by measuring simultaneously adult attachment style and social anhedonia. In this study, we measured individual differences in social hedonic capacity and analyzed their correlations with a dimensional measure of adult attachment style in a relatively large sample of healthy volunteers. We hypothesized that avoidant attachment, but not anxious attachment, was positively correlated with higher levels of social anhedonia. Studying the relationship between attachment and social anhedonia is important to clarify the developmental pathways leading to and originating from social withdrawal (Rubin, Coplan, & Bowker, 2009). Since a deficit in the experience of social pleasure is a major risk factor for different psychiatric disorders (Watson & Naragon-Gainey, in press), the identification of developmental factors associated with social anhedonia may enable high risk populations to be delineated. 2. Method 2.1. Participants Data reported here were collected as a part of a larger study aimed at investigating the personality correlates of adult attachment styles. One hundred and sixty three healthy volunteers (mean age: 29.3 ± 9.3 years; range: 19–67 years) were recruited among students in the medical school, paramedic staff members, and conscripts of the Italian army. Participants with personality disorders and/or psychiatric disorders were screened out of the protocol. Exclusion from the sample was based on the presence of a DSM-IV diagnosis, not on the scores of psychometric instruments administered to participants. Diagnostic assessment was made by experienced clinical psychiatrists using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-CV) (First, Gibbon, Spitzer, & Williams, 1997) and the Schedule for Interviewing DSM-IV Personality Disorders-IV (SIDP-IV) (Pfohl, Blum, & Zimmerman, 1997). The University Intramural Ethical Committee approved all procedures and protocols, and written informed consent was obtained before enrollment. All the participants were blind to the aims of the study. 2.2. Psychometric assessment The social anhedonia subscale of the Snaith–Hamilton Pleasure Scale (SHAPS; Snaith et al., 1995) was used to measure the capacity to experience pleasure in social situations. The SHAPS is a 14-item questionnaire instructing participants to agree or disagree with statements of hedonic response in pleasurable situations. Each of the items has a set of four response categories ranging from 1 (definitely agree) to 4 (definitely disagree). A higher total score indicates higher levels of anhedonia. This scale has shown adequate overall psychometric properties in clinical and student samples (Franken, Rassin, & Muris, 2007; Gilbert, Allan, Brough, Melley, & Miles, 2002). The SHAPS covers four domains of hedonic experience: interest/pastimes, social interaction, sensory experience, and food/drink. The social anhedonia subscale (SHAPS–SOC) includes statements such as ‘‘I would enjoy being with family or close friends” and ‘‘I would enjoy seeing other people’s smiling faces.” Participants were instructed to compile the SHAPS to describe their habitual hedonic responses, not their experiences in the last few days. The Attachment Style Questionnaire (ASQ; Feeney, Noller, & Hanrahan, 1994) was used to measure adult attachment style. The ASQ is a 40-item self-report questionnaire with individual items being scored on a six-point scale from 1 (totally disagree) to 6 (totally agree). The ASQ refers to all close relationships with
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peers (whether romantic or not) and includes five subscales derived from principal-components analysis: confidence (in self and others), discomfort with closeness, Need for Approval, Preoccupation with Relationships, and Relationships as Secondary (to achievement). The five scales of the ASQ have been shown to have adequate internal consistency, with Cronbach’s a coefficients ranging from 0.76 to 0.84 and 10-week retest reliability coefficients ranging from 0.67 to 0.78 (Feeney et al., 1994). The confidence subscale is a general measure of the security of attachment. The Need for Approval and the Preoccupation with Relationships subscales assess the anxiety (about abandonment) dimension of the attachment style, whereas the discomfort with closeness and the Relationships as Secondary subscales pertain primarily to the avoidance (of intimacy) dimension of the attachment style. Individuals scoring highly on attachment-related anxiety endorse statements such as ‘‘I find that others are reluctant to get as close as I would like” and ‘‘It’s important to me that others like me”. Individuals scoring highly on attachment-related avoidance endorse statements such as ‘‘My relationships with others are generally superficial” and ‘‘Achieving things is more important than building relationships”. To control for the confounding effect of current mood on the assessment of attachment and social anhedonia, participants were asked to compile the Profile of Mood States (POMS; McNair, Lorr, & Droppleman, 1992). They were asked to carefully read each of 65 items, then respond to a five-point Likert scale ranging from 1 (not at all) to 5 (extremely) based on how they were feeling the day they completed the inventory. The total mood disturbance score (POMS–TMD) was calculated by summation of the five negative affect scales (fatigue, depression, tension, anger, and confusion) and subtraction of the vigor scale. A higher POMS–TMD corresponds to higher levels of mood disturbance. 2.3. Statistical analysis Comparisons between men and women were performed using t test. Pearson coefficients of correlation (r) were used to calculate bivariate correlations between variables. Stepwise regression analysis was used to identify the significant predictors of the SHAPS– SOC score. Collinearity diagnostics based on eigenvalues of the scaled and uncentered cross-products matrix, variation inflation factors (VIF) and tolerances for individual variables were used to exclude multicollinearity among the independent variables. Analysis was performed on a personal computer using SPSS for Windows, version 17.0 (SPSS, Inc., Chicago, Ill). 3. Results Preliminary analyses aimed at ascertaining whether social anhedonia was related to gender, age or mood state. None of these variables were related to the SHAPS–SOC score, as shown by the non-significant difference between men and women (t = 0.73, df = 161, NS) and by the non-significant correlations with age (r = 0.08, NS) and POMS–TMD score (r = 0.10, NS). The results did not change when the sample was stratified by gender (Table 1). Thus, we could exclude that associations between social anhedonia and adult attachment styles were due to the confounding effects of gender, age or mood state. We found significant bivariate correlations between the SHAPS– SOC score and two scales of the ASQ (Confidence and Discomfort with Closeness) (Table 1). Higher levels of attachment insecurity corresponded to higher levels of social anhedonia. To clarify which dimensions of insecure attachment were the best predictors of social anhedonia, we next fit a stepwise regression model with the SHAPS–SOC score as the dependent variable and the five ASQ
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Table 1 Bivariate correlations between social anhedonia and age, mood state, and attachment ratings for the participants divided by gender.
Age POMS–TMD ASQ CON ASQ DIS ASQ RAS ASQ PRE ASQ NFA
Women (N = 110)
Men (N = 53)
r = 0.01 r = 0.17 r = 0.25** r = 0.22* r = 0.18 r = 0.07 r = 0.06
r = 0.19 r = 0.05 r = 0.21 r = 0.27* r = 0.16 r = 0.03 r = 0.21
POMS–TMD, total mood disturbance score of the Profile of Mood States; ASQ, Attachment Style Questionnaire; ASQ CON, confidence scale; ASQ DIS, discomfort with closeness scale; ASQ RAS, Relationships as Secondary scale; ASQ PRE, Preoccupation with Relationships scale; ASQ NFA, Need for Approval scale. * P < 0.05. ** P < 0.01.
scales as the independent variables. The resulting equation was significant (F = 7.13, df = 2, 160, P < 0.001) and explained 8.2% (R2) of the variance in the SHAPS–SOC score. The Confidence and the Discomfort with Closeness scales emerged as significant predictors of the SHAPS–SOC score, indicating that, among the healthy participants of this study, higher levels of social anhedonia were associated with avoidant attachment but not with anxious attachment (Table 2). 4. Discussion Confirming the hypothesis of the study, we found that, compared with participants with a secure style of adult attachment, participants with insecure attachment experienced less pleasure and reward from social affiliative interactions. The dimension of insecure attachment that was correlated with social anhedonia was avoidance but not anxiety. To our knowledge, no previous study has directly investigated the relationship between adult attachment and social hedonic capacity by using a psychometric scale designed to measure social anhedonia. Thus, our findings are not comparable with others in the literature. However, in line with the results of the present study, several studies focusing on adult attachment and the process of interpersonal regulation have documented a specific relationship between attachments and selfreport of diminished interest in social interactions. Diary techniques have been used to study how people react to daily interactions with different kinds of relationship partners (Kafetsios & Nezlek, 2002; Pierce & Lydon, 2001; Pietromonaco & Barrett, 1997; Tidwell, Reis, & Shaver, 1996). Despite methodological differences in the assessment of attachment, these studies have consistently shown that, compared with secure people, avoidant individuals experience a lack of engagement in social interactions, which leads them to feel bored and distant. In addition, they tend to report lower levels of satisfaction, intimacy, self-disclosure, supportive behavior, and positive emotions during daily interactions. In contrast, anxious people are similar to secure ones in their reports of intimacy and satisfaction but different in reports of higher negative emotions and feelings of rejection, especially when interacting with opposite-sex partners.
Table 2 Stepwise regression analysis: ASQ scales as predictors of social anhedonia. B Constant ASQ CON ASQ DIS
SE B 6.05 0.06 0.04
ASQ, Attachment Style Questionnaire; R2 = 0.08. * P < 0.05.
1.26 0.03 0.02
b 0.18* 0.17*
It is worth noting that, in our study, adult attachment style explained only a small portion (8.2%) of the variance in social anhedonia. This is not surprising considering that individual differences in the capacity to experience social reward are likely to involve a complex interplay of genetic and environmental variables, including genetic variation, early experience and current situational factors. However, another factor that may explain the weak relationship between attachment and social anhedonia is the composition of our sample. We screened out individuals with DSM-IV Axis I or Axis II disorders and studied a very healthy sample. It is possible that in clinical samples including patients with psychiatric disorders and/or personality disorders associated with high levels of social anhedonia and attachment insecurity, the statistical correlations between these variables are substantially stronger. Future studies should test such a hypothesis by focusing on those mental and behavioral disorders that present anhedonia as a core psychopathological symptom, including major depression, negative schizophrenia, substance use disorder, and eating disorders. Our findings raise interesting questions about the causal link between avoidant attachment and social anhedonia. According to attachment researchers, avoidant people steer clear of intimate exchanges that might facilitate attachment formation because they have negative expectations and are vulnerable to rejection (Bartholomew, 1990; Fraley, Davis, & Shaver, 1998). Based on this view, the social anhedonia of avoidant individuals would be a defense against attachment-related distress rather than a primary deficit in the capacity to experience pleasure and reward from social affiliation. We agree that it is possible for some people to defensively report that they are not rewarded by social interactions, when actually they are rewarded, and for some not to have conscious access to their desire for intimate relationships even though such a desire exists. Partial support for this interpretation comes from our finding that not only the ASQ scale measuring avoidant attachment but also the scale measuring attachment insecurity was correlated with social anhedonia. However, an alternative interpretation is that the construct of avoidant attachment as measured by self-report scales includes a heterogeneous group of individuals and that some have a basic deficit in the capacity to experience social reward rather than a defensive deactivation of intimacy needs. If this is the case, then avoidant attachment is secondary to social anhedonia. Such a hypothesis would imply a basic dysfunction in the neural circuitry that modulates social hedonic responses rather than ‘‘learned” anhedonia caused by negative attachment experiences in early infancy and childhood (e.g., unrewarding interactions with unresponsive caregivers). In line with this alternative interpretation, we found that social anhedonia did not correlate with either of the two scales of the ASQ that reflect anxiety about abandonment and rejection. In addition, there was no correlation between social anhedonia and negative affect, as measured by the POMS. Translated into the language of attachment research, this means that social anhedonia seems to be related more with dismissing-avoidant attachment than fearfulavoidant attachment. There are important differences between fearful and dismissing individuals, although both share a detached stance toward others. Fearful individuals have negative self-models which are reflected in high emotional dependence, high jealousy, and high separation anxiety. Their avoidance of intimacy is due to fear of rejection. In contrast, dismissing individuals have a positive self-model. They have a moderate to high sense of selfconfidence. These individuals downplay the importance of relationships, stress the importance of emotional independence and tend neither to be jealous nor to be anxious when separated from significant others. They maintain an emotional distance from others because they are uncomfortable with affection and do not like other people very much (Bartholomew & Shaver, 1998).
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Similar findings have been reported by a recent study using experience-sampling methodology to explore deviations in social attachment (or ‘‘the need to belong” in the authors’ terminology) in the daily lives of 245 undergraduates (Brown et al., 2007). Higher levels of social anhedonia were associated with increased time alone, greater preference for solitude, and lower positive affect. Higher social anxiety, in contrast, was associated with higher negative affect and was not associated with increased time alone. The authors concluded that deviations in the need to belong affect social functioning differently depending on whether this need is absent or thwarted. Neurobiological research has also provided preliminary evidence that avoidant attachment can reflect a diminished capacity to experience pleasure from social contact which is largely independent from fears of rejection. Using functional magnetic resonance imaging (fMRI) in healthy volunteers, Vrticˇka, Andersson, Grandjean, Sander, and Vuilleumier (2008) examined how adult attachment styles modulate brain responses to facial expressions conveying either positive or negative feedback about task performance in a social game context. They found that, in response to positive feedback signaled by a smiling face, participants with avoidant attachment showed lower activation in brain regions linked to social reward, including both ventral striatum and ventral tegmental area. Their relative impassiveness to social reward was independent from sensitivity to social punishment, an emotional trait characteristic of participants with anxious attachment and reflected by an increased left amygdala response to signals of social reproach. This study has three major limitations. First, screening out people with psychiatric disorders, we excluded participants with extreme scores and reduced the power of statistical analysis. However, because there were no previous studies of the relationship between adult attachment and anhedonia, we decided to study healthy subjects to increase the generalizability of our preliminary findings. Second, we used self-report scales. Although there is evidence that self-report measures of attachment (Mikulincer & Shaver, 2007) and social anhedonia (Kwapil et al., 2009) are predictably related to interpersonal behavior, future studies aimed at replicating our findings should combine self-report measures with direct observation of attachment behavior and hedonic responses in natural social contexts and experimental settings. Third, we did not collect data about participants’ early experiences. These retrospective data would be useful to ascertain to what extent social anhedonia is secondary to negative attachment experiences with primary caregivers. 5. Conclusions The present study is an initial step in analyzing the relationship between attachment style and social hedonic capacity and addresses a small fraction of the theoretical questions that can be explored in future studies. To resolve the ambiguity that complicates the interpretation of causal links, we need to integrate the great deal of knowledge about the cognitive, emotional, and behavioral correlates of attachment styles with the recent findings of genetic (Ebstein et al., 2009; Israel et al., 2008) and neurobiological studies (Heinrichs & Domes, 2008) of social attachment and affiliative behavior. Acknowledgments We are grateful to Giorgio Di Lorenzo, Luca Proietti and Elena Battellocchi for assistance with the larger study of which this is one part.
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