Attachment style moderates partner presence effects on pain: a laser-evoked potentials study

doi:10.1093/scan/nsu156 SCAN (2015) 10,1030 ^1037 Attachment style moderates partner presence effects on pain: a laser-evoked potentials study Charlotte Krahé,1,2 Yannis Paloyelis,2 Heather Condon,3 Paul M. Jenkinson,3 Steven C. R. Williams,2 and Aikaterini Fotopoulou4 1 Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK, 2Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK, 3Department of Psychology, University of Hertfordshire, Hertfordshire, UK, and 4Research Department of Clinical, Educational and Health Psychology, University College London, London, UK Keywords: social presence; social support; pain; attachment style; laser-evoked potentials INTRODUCTION Human experience is inextricably embedded within a social world, from being part of a wider society to forming close relationships with other individuals. A key function of social connection is the provision of help and support in the face of threat (Bowlby, 1997/1969; Coan, 2008). Beneficial effects of social support have been found regarding a range of threats to physical and psychological well-being (Uchino, 2006). Studies investigating the mechanisms by which social support affects well-being have mainly focused on neuroendocrine stress responses (Kikusui et al., 2006). However, more recently, the emerging field of social cognitive neuroscience has begun to examine the central neural mechanisms associated with receiving social support (reviewed in Eisenberger, 2013). Several such studies have focused on the neural mechanisms mediating the effects of social support on pain. Two studies primed concepts of social support by presenting participants in pain with photographs of different social partners and found that viewing photographs of the romantic partner reduced pain ratings relative to viewing pictures of strangers, acquaintances, or objects (Younger et al., 2010; Eisenberger et al., 2011). Neural activity which correlated with pain reduction in the partner photograph conditions was found in brain regions associated with signalling safety (the ventromedial prefrontal cortex; Eisenberger et al., 2011) and reward (e.g. nucleus accumbens; Younger et al., 2010). However, these studies did not test the effects of a social partner who was physically present during pain. To our knowledge, only one neuroscientific study has experimentally investigated the effects of a physically present Received 29 July 2014; Revised 7 October 2014; Accepted 24 December 2014 Advance Access publication 1 January 2015 This study was supported by a project grant (II/85 069) from the Volkswagen Foundation ‘European Platform for Life Sciences, Mind Sciences and Humanities’ (to A.F.). A.F. was supported by a European Research Council Starting Investigator Award (ERC-2012-STG GA313755). Y.P. was supported by an Economic and Social Research Council fellowship (grant number ES/K009400/1). Correspondence should be addressed to Charlotte Krahé, Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK. E-mail: . partner, but in relation to the anticipation of pain rather than the experience of pain itself. Coan et al. (2006) measured neural activity while participants were holding the hand of their romantic partner or a stranger, or holding no hand, during the threat of impending electric shocks. Participants reported lowest unpleasantness feelings when holding their partner’s hand, and associated activation was found in brain regions implicated in the regulation of emotion (e.g. the dorsolateral prefrontal cortex and caudate nucleus). This study aimed to go beyond the above insights by examining how the perception of experimentally administered noxious stimuli was influenced by the actual presence of one’s romantic partner. Moreover, while neuroimaging studies highlight that social support from close others may be beneficial in reducing pain, behavioural studies into the effects of supportive social presence on pain have revealed a more complex picture (Krahé et al., 2013). Social presence has been found to attenuate (Brown et al., 2003) or increase pain (McClelland and McCubbin, 2008). These mixed results suggest the need to study not only how specific social contextual factors may modulate pain and related neural responses but also how personality factors may interact with such contextual variables. A key personality factor that may influence the effects of social presence on pain is adult attachment style (AAS). AAS describes individual differences in representational models of close relationships which originate from early interactions with caregivers, remain relatively stable across the lifespan (Waters et al., 2000), and apply to adult romantic relationships (Hazan and Shaver, 1987). Differences in AAS are frequently conceptualized along dimensions of attachment anxiety and avoidance (Fraley et al., 2000). Individuals high on the anxiety but low on the avoidance dimension are anxiously attached. They crave closeness but fear abandonment, while individuals high on the avoidance but low on anxiety dimension are avoidantly attached and find it difficult to trust and depend on their partner (Hazan and Shaver, 1987). These ‘insecure’ attachment styles have been associated with increased pain in experimental (Meredith, 2013) and clinical settings (e.g. in labour; Costa-Martins et al., 2014), and have been proposed to ß The Author (2015). Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. Social support is crucial for psychological and physical well-being. Yet, in experimental and clinical pain research, the presence of others has been found to both attenuate and intensify pain. To investigate the factors underlying these mixed effects, we administered noxious laser stimuli to 39 healthy women while their romantic partner was present or absent, and measured pain ratings and laser-evoked potentials (LEPs) to assess the effects of partner presence on subjective pain experience and underlying neural processes. Further, we examined whether individual differences in adult attachment style (AAS), alone or in interaction with the partners level of attentional focus (manipulated to be either on or away from the participant) might modulate these effects. We found that the effects of partner presence vs absence on pain-related measures depended on AAS but not partner attentional focus. The higher participants attachment avoidance, the higher pain ratings and N2 and P2 local peak amplitudes were in the presence compared with the absence of the romantic partner. As LEPs are (...truncated)