Emotional responsiveness task in emotional distress: correlated of functional neuroimaging in anorexia and bulimia

Aim The present study aims to extend the knowledge of the neural correlates of emotion processing in first episode subjects affected by anorexia nervosa (AN) or bulimia nervosa (BN). We applied an emotional distress paradigm targeting negative emotions thought to be relevant for interpersonal difficulties and therapeutic resistance mechanisms. Methods The current study applied a neuroimaging paradigm eliciting affective responses to 44 female participants with newly diagnosed AN or BN and 20 matched controls. The measurements also included an extensive assessment comprised of clinical scales, neuropsychological tests, measures of emotion processing and empathy. Results AN and BN did not differ from controls in terms of emotional response, emotion matching, self-reported empathy and cognitive performance. However, scores of eating disorder and psychopathological clinical scores, as well alexithymia levels, were increased in AN and BN. On a neural level, no significant group differences emerged, even when focusing on a region of interest selected a priori: the amygdala. Conclusions Our data are against the hypothesis that participants with AN or BN display a reduced emotional responsiveness. This supports the hypothesis that relational difficulties, as well as therapeutic resistance, are not secondary to simple difficulty in feeling and identifying basic negative emotions in AN and BN participants.


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Introduction 48 Anorexia nervosa (AN) and Bulimia nervosa (BN) are the two major Eating Disorders (ED): 49 serious and complex psychiatric conditions with a multifactorial biopsychosocial 50 pathogenesis often characterized by a chronic and disabling course and only partial 51 therapeutic success [1,2]. Young girls are especially affected by AN, which is the 52 pathology with the highest mortality risk and the lowest response to treatment across ED 53 [3]. Prioritizing the treatment of symptoms results in better outcomes in BN and allows 54 dealing with the main cause of mortality in AN [4]. It remains controversial whether doing 55 so ignores core psychopathological elements, linked to more complex symptoms and long-56 term outcomes such as relationship difficulties or impairments in affect regulation, 57 reflective functioning, and coherence of mind [5]. Psychotherapeutic treatment often 58 focuses on these aspects and therapists are frequently faced with marked difficulty in 59 engaging subjects affected by AN and maintaining treatment adherence [6]. In BN the 60 difficulties are related to coping with high emotional arousal when facing social and 61 affective stimuli. These difficulties also challenge a complex therapeutic approach [7].  Empathy represents a core function for social coherence and building relationships [10]. 70 Based on the abovementioned socio-emotional difficulties and related problems in ED, one 71 may assume that empathy is systematically altered in ED and its impairment potentially 72 represents a relevant risk factor. Several studies applied self-reported empathy measures disgust) or containing a neutral content (e.g. 'You are on the couch watching television').

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As reported previously, stimuli were validated by independent female and male raters [32] 145 and only stimuli that were clearly classified as belonging to one emotional category (>70%) 146 were selected for the study. We presented 10 sentences per condition (disgust, anger, 147 fear, neutral). Participants had to imagine how they would feel if they were experiencing 148 those situations. We were particularly interested in the emotional response to distressful as a proxy of the sustained attention and active participation to the task (score 0-10).

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The order presentation of neutral and emotional stimuli was counterbalanced across 162 participants. Figure 1 illustrates an example of the task. Further information on the 163 experimental design can be found in the supplementary material (section S1.2).  The participants gave correct answers in more than 85% of the trials, and the number of

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Emotion ROI analyses: We performed region of interest (ROI) analyses on brain areas (left 220 and right amygdala) that were selected a priori as they have been consistently reported as   p<.001; disgust>fear, p<.008). The control task was easier than all the emotion tasks (all 263 p<0.001). Please see Table 2 for further details.   The contrasts for the group factor did not show significant activation differences in the 274 brain.

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ROI analyses of the left and right amygdala revealed no significant differences between 277 group, confirming whole-brain results (see Figure 2).

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Relying on self-report data and an affective responsiveness task, we must argue against 345 the hypothesis that participants with ED display reduced emotional responsiveness. This 346 supports the hypothesis that relational difficulties, as well as therapeutic resistance, are 347 not secondary to simple difficulty in feeling and identifying basic negative emotions in first 348 episode, treatment-naive AN and BN participants.

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According to the theories which link the pathogenesis of anorexia nervosa to attachment 350 processes [48,49], the present findings support the hypothesis that the difficulty in building 351 meaningful relationships which characterize young women with ED may be more related to 352 attachment issues based on early attachment experiences rather than from current 353 difficulties in the emotional responsiveness to their own and others emotions. The authors declare no conflicts of interest. This research received no specific grant from 356 any funding agency, commercial or not-for-profit sectors.

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The data that support the findings of this study are available from the authors, without 358 undue reservation, to any qualified researcher.