216 Personality and Social Psychology Review 18(3) exist literature is reviewed to assess the degr sline for hatter)within a day of the str available evidence supports each of these It therefore appears that people are uniquely sensitive to Finally,"An Agenda for Research Into Social Identity and social forms of stress(such as rejection or conflict)relative Depression"highlights current gaps in the evidence and s to of e events theore cal und rstandin ific ep ness and depression but also to enhancing clinical interven (Tennant,2002).Most commonly,this is a social loss of tions that target its prevention and treatment.In this,our goa some kind such as the death of a loved one,but it may als s to present a novel anal the r le of social conne from othe venues of investigation and of informing clinical practice of depression but also appears to have a causal rolen t The Im ortant Role of Social development n Depression a third way inw hich s ocial connectedne Clinical depression is understood by nd p remission and recovery.Here,there is evidence that impaire tioners alike to be more than simply low mood.n addition social functioning often persists long after remission(C orvel tofeeling miserable,apathetic, and self- 1993;Kennedy,Foy,Sherazi,Mcdor ough,M ng an epis of major de pression als 1989:pa which is social withdrawal.Depression is typically charac Rassaby. 1980)Low social support also predicts terized by social isolation and reduced social connectedness response to treatment and early dropout(Trivedi etal,200 5 of thi has箱 dia gno of el ymntoms and is a core c ent of effective der essio treatment.More specifically CBT for depression (Beck 2011)acknowledges that social isolation isa central featur formally (e.g h pre RT cha impairment in this domain is significantly more common in condition than in other physical and mental illnesses n tha ngfu in her rities that also a sense of pleasure or success,particularly activities that strong risk actor for reppomoonhEn9ealgotevah e approac no ppo. social functioning relative to pharmacological .Kiecol-Gaser,)Fore treatments(Scott et al,2012). Hawkley,and Thisted (2010) found tha a broad foc lation was a goodn val o s on al nd date social connectedness specificallyea by helping a physical health.stress,and a number of objecti e indicator patient rejoin a sports team)rather than other kinds of acti ofs cial-relationship quality;Cacioppo et al ,2010).Lack (e.g.,by daily wall supp ial in but is rather th to be analysis.Bolger.DeLongis.Kessler. ncreased rate of positive reinforcement(Dimidjian,Martell (1989)found that interpersonal conflict was the most impor Addis,Herman-Dunn,2008).Lack of effective social for pre licting daily fluctuatic th nflict had individual (i.e.."me")rather than as a p roblem that i over a number of days.whereas for other kinds of stressor associated with the sense of the self derived from member there was evidence of habituation such that mood returned to ship in a social group ("us).For this reason,a range of216 Personality and Social Psychology Review 18(3) existing literature is reviewed to assess the degree to which available evidence supports each of these hypotheses. Finally, “An Agenda for Research Into Social Identity and Depression” highlights current gaps in the evidence and sets out an agenda for future research, with a view not only to formulating a theoretical understanding of social connected￾ness and depression but also to enhancing clinical interven￾tions that target its prevention and treatment. In this, our goal is to present a novel analysis of the role of social connected￾ness in depression capable of stimulating new and fruitful avenues of investigation and of informing clinical practice. The Important Role of Social Relationships in Depression Clinical depression is understood by researchers and practi￾tioners alike to be more than simply low mood. In addition to feeling miserable, apathetic, and self-critical, a person experiencing an episode of major depression also exhibits a cluster of cognitive and behavioral changes, chief among which is social withdrawal. Depression is typically charac￾terized by social isolation and reduced social connectedness (Wade & Kendler, 2000). One of its core symptoms (which is as central to diagnosis as low mood) is anhedonia—loss of interest or pleasure in previously enjoyed activities (American Psychiatric Association, 2000). This most typi￾cally manifests as withdrawal from social relationships, both formally (e.g., quitting sporting groups) and informally (e.g., seeing friends less often). Reduced social connected￾ness is thus a key characteristic of depression, such that impairment in this domain is significantly more common in this condition than in other physical and mental illnesses (Hirschfeld et al., 2000). Critically, marked differences in social connectedness also emerge prior to the development of depression symp￾toms. Social isolation has therefore been observed to be a strong risk factor for the development and recurrence of depression (Cacioppo, Hughes, Waite, Hawkley, & Thisted, 2006; Glass, De Leon, Bassuk, & Berkman, 2006; Uchino, Cacioppo, & Kiecolt-Glaser, 1996). For example, in one study, Cacioppo, Hawkley, and Thisted (2010) found that perceived social isolation was a good longitudinal predictor of depression symptoms even after controlling for key candi￾date variables (demographic characteristics, personality, physical health, stress, and a number of objective indicators of social-relationship quality; Cacioppo et al., 2010). Lack of social support has also been found to predict suicidal ide￾ation 1 year later (Handley et al., 2012). In a more fine￾grained analysis, Bolger, DeLongis, Kessler, and Schilling (1989) found that interpersonal conflict was the most impor￾tant stressor for predicting daily fluctuations in negative mood. In addition, these researchers observed that interper￾sonal conflict had escalating effects on mood if it continued over a number of days, whereas for other kinds of stressors, there was evidence of habituation such that mood returned to baseline (or better) within a day of the stressor commencing. It therefore appears that people are uniquely sensitive to social forms of stress (such as rejection or conflict) relative to other stressful life events. Taken a step further, an episode of depression is often triggered by a specific negative event in the social sphere (Tennant, 2002). Most commonly, this is a social loss of some kind such as the death of a loved one, but it may also result from other factors such as family conflict, workplace bullying, or a relationship breakdown (Paykel, 1994). As a result, reduced social connectedness is not only symptomatic of depression but also appears to have a causal role in its development. There is also a third way in which social connectedness is implicated in depression, and this pertains to processes of remission and recovery. Here, there is evidence that impaired social functioning often persists long after remission (Coryell et al., 1993; Kennedy, Foy, Sherazi, Mcdonough, & Mckeon, 2007) and increases the risk of relapse (George, Blazer, Hughes, & Fowler, 1989; Paykel, Emms, Fletcher, & Rassaby, 1980). Low social support also predicts poor response to treatment and early dropout (Trivedi et al., 2005). As a corollary of this, social connectedness has also been found to play a role in the alleviation of depression symptoms and is a core component of effective depression treatment. More specifically, CBT for depression (Beck, 2011) acknowledges that social isolation is a central feature of presentation and often requires targeted intervention. In this regard, behavioral activation is a key CBT strategy that directly targets social connectedness (Cuijpers, Van Straten, & Warmerdam, 2007; Veale, 2008). This technique is pred￾icated on the assumption that withdrawal from meaningful activities maintains depressive symptoms. Patients are therefore encouraged to schedule activities that bring them a sense of pleasure or success, particularly activities that were previously important to them. Speaking to the value of this approach, although it has not been a focus for research attention, there is some evidence that CBT improves social functioning relative to pharmacological treatments (Scott et al., 2012). However, behavioral activation has a broad focus on all kinds of withdrawal or inactivity, and therefore each treat￾ment and practitioner varies in the degree to which they tar￾get social connectedness specifically (e.g., by helping a patient rejoin a sports team) rather than other kinds of activ￾ity (e.g., by helping a patient recommence daily walks). This is because the proposed mechanism of behavioral activation is not social in nature but is rather theorized to be an increased rate of positive reinforcement (Dimidjian, Martell, Addis, & Herman-Dunn, 2008). Lack of effective social functioning in depression is also typically conceptualized as an individual-level deficit—associated with the individual as an individual (i.e., “me”) rather than as a problem that is associated with the sense of the self derived from member￾ship in a social group (“us”). For this reason, a range of Downloaded from psr.sagepub.com at Remen University of China on September 6, 2015