Social trauma : consequences of emotional maltreatment on physiological reactions to social rejection in subjects with social anxiety disorder

A history of child maltreatment is associated with psychopathology, predominantly affective and anxiety disorders as well as substance abuse. In the past, research has primarily focused on the consequences of physical abuse, sexual abuse, physical neglect or combinations of these types of maltreatment. However, besides physical and sexual transgressions, child maltreatment does also involve emotional abuse and emotional neglect. Although it was suggested that the consequences of emotional maltreatment might be as severe as the outcomes of physical or sexual maltreatment, there is little knowledge about the unique effects of emotional maltreatment on psychopathology. However, there is a growing body of evidence for an association of emotional maltreatment by caretakers and psychopathology, particularly social anxiety. In addition to emotional maltreatment that involves abuse and neglect by parents and other caretakers, emotional abusive treatments (also referred to as emotional victimization) are highly prevalent among peers. Similar to emotional maltreatment by parents or caretakers, emotional peer victimization contributes to various forms of general psychopathology, e.g., depression, anger-hostility, dissociation, and drug use. However, peer victimization is particularly associated with characteristics of social anxiety disorder. Social anxiety disorder (SAD) is a common anxiety disorder, which is characterized by persistent fear of social or performance situations, fear of negative evaluation, social avoidance of general and new situations, as well as physiological symptoms in social situations. However, the mechanisms that associate emotional maltreatment by caretakers as well as peers and social anxiety are still unknown. Models of cognitive vulnerability suggest that negative learning experiences establish associative information structures in memory that activate various stereotype and pathological behavioral programs in similar situations. This conceptualization predicts that social events may provoke more intense reactions in emotional maltreated subjects as such situations trigger associative response elements of social traumatic experiences. A key element of emotional maltreatment is social rejection. Experiences of social rejection elicit negative mood, emotional distress, and activity of neural networks that are associated with the processing of physical pain. However, because physiological reactions to social rejection were found to be ambiguous, there remains a need for clarification of the impact and direction of social rejection on other physiological measures such as heart rate and skin conductance. In socially anxious subjects, social rejection elicited immediate and delayed effects on psychological outcomes. Therefore both, physiological reactions in healthy subjects as well as increased psychological reactions in socially anxious subjects were suggested in previous studies. However, a combination of these, i.e., an investigation of physiological reactions in socially anxious subjects, was not presented, yet. This might be of specific interest, as fear of social rejection is one of the core components of social anxiety. Accordingly, socially anxious subjects should present stronger and prolonged physiological reactions to social rejection. However, there is so far minimal evidence that experiences of aversive social situations evoke an associative network and an activation of associative memory processing. The aim of the present work was to address this point and to explore the impact of prior emotional maltreatment on physiological reactions to social rejection. In addition, it was assumed that associative memory representations are potential links between maltreatment and social anxiety disorder. Thus, the effect of a history of emotional maltreatment on the experience of potential traumatic social events was expected to be even stronger for subjects with SAD. In a first step, the association of emotional maltreatment with social anxiety was examined. Results indicate a relation of childhood maltreatment with psychopathology, and in particular, social anxiety symptoms. Moreover, it was demonstrated that the relative impact of emotional forms of abuse and neglect might even be higher than indicated by previous research on child maltreatment, which had mainly focused on physical and sexual types of abuse and neglect. Moreover, emotional maltreatment mediated the association of physical maltreatment and social anxiety. In addition to emotional maltreatment through parents and other caretakers, reports of emotional peer victimizations were independently related to social anxiety symptoms. Thus, it was concluded that symptoms of social anxiety are mainly predicted by emotional types of victimization, either in childhood through the caretakers, or during childhood and adolescence through peers. As a second step, physiological reactions to social rejection were examined in healthy subjects. The results suggest that social rejection evokes reactions of the autonomic nervous system (ANS) apparent in accelerated heart rates. Although the effects of social rejection did not imply changes of skin conductance levels, it was concluded that the autonomic nervous system is affected by experiences of social exclusion indicating that behavior activation rather than inhibition is associated with socially threatening events. After that the link between social rejection and physiological reactions had been established, it was examined whether these reactions are affected by histories of emotional maltreatment and symptoms of social anxiety. Data suggested that reactions to an episode of social exclusion were primarily influenced by the degree of relational peer victimization rather than by the diagnosis of SAD. While an increase in skin conductance immediately after the exclusion was observed for all groups of subjects, this physiological response was attenuated among the subjects with a history of peer victimization. In general, the results provided evidence for the existence and significance of associative networks and associative memory processing that is established by experiences of emotional maltreatment. In line with memory models of traumatic events and network models of emotional processing, a history of emotional maltreatment altered physiological reactions to a social challenge. After it has been demonstrated that experiences of emotional maltreatment place individuals at risk for symptoms of social anxiety disorder, findings indicate that associative information processing may account for an enhanced cognitive vulnerability for social anxiety. Although the mechanisms involved remain uncertain, it may be speculated that altered physiological reactivity in subjects with a history of emotional maltreatment contributes to the development of social anxiety. Importantly, the findings of the present research highlight the role of emotional forms of abuse and neglect in the development of a wide range of psychological disorders. Besides the impact of emotional maltreatment on social anxiety, the present research suggested influences of emotional maltreatment on various types of psychopathology. These findings establish a cross-diagnostical perspective on the consequences of emotional maltreatment. Assuming that experiences of emotional abuse and neglect account for various forms of symptomatology, it may be speculated that a plurality of patients would benefit from treatments that address these experiences. Therefore, the development of therapeutic interventions that combine disorder-specific treatments with an approach that focuses on adverse life experiences including social trauma should be a main goal of future clinical research.