Neurobiological signature of intimacy in anorexia nervosa.

BACKGROUND: Intimacy and psychosexual development represent core problems of anorexia nervosa (AN). Experiential and neurobiological evidence however is scarce. MATERIAL AND METHODS: Thirty-one female AN patients were compared with 35 non-patients (NP) and 22 recovered participants (REC) by using functional magnetic resonance imaging. Participants viewed pictures of couples in intimate relationships and control stimuli. RESULTS: AN patients experienced intimate stimuli with lower valence and dominance. AN showed decreased activation of parietal cortices. NP decreased the prefrontal cortex response, which AN patients did not. REC participants did not differ from NP on a behavioural level, though with regard to the neural signature. DISCUSSION: Parietal cortices are related to processing of erotic themes, which seems to be deficient in AN. Dysfunction of prefrontal cortices likely mirrors dysfunctional control in AN. The neural signature does not seem to be state-related considering results of REC.

Self-perspective leads to increased activation of pain processing brain regions in fibromyalgia.

BACKGROUND: Dysfunction of central nervous pain processing is assumed to play a key role in primary fibromyalgia (FM) syndrome. This pilot study examined differences of pain processing associated with adopting different interpersonal perspectives. METHODS: Eleven FM patients and 11 healthy controls (HC) were scanned with functional magnetic resonance imaging. Participants were trained to take either a self-perspective or another person's perspective when viewing the visual stimuli. Stimuli showed body parts in painful situations of varying intensity (low, medium, and high) and visually similar but neutral situations. RESULTS: Patients with FM showed a higher increase in blood oxygen level dependent (BOLD) response, particularly in the supplementary motor area (SMA). All pain-related regions of interest (anterior insula, somatosensory cortices, anterior cingulate cortex, and SMA) showed stronger modulation of BOLD responses in FM patients in the self-perspective. In contrast to pain processing regions, perspective-related regions (e.g. temporoparietal junction) did not differ between FM and HC. CONCLUSIONS: The stronger response of all four pain processing cerebral regions during self-perspective is discussed in the light of disturbed bottom-up processing. Furthermore, the results confirm earlier reports of augmented pain processing in FM, and provide evidence for sensitization of central nervous pain processing.

Emotional perception in patients with eating disorders in comparison with depressed patients.

OBJECTIVE: Emotion regulation is a key issue for many psychiatric and psychosomatic disorders, including eating disorders. Eating disordered patients (EDP) show high levels of depressive comorbidity, and there is much uncertainty about disorder-specific deficits. This study is aimed at delineating disorder-specific disturbances of emotional perception in EDP. METHOD: Fifty-two EDP were compared with 35 depressed patients (DP) and 25 healthy controls. They rated their emotional experience when viewing visual emotional stimuli. Emphasis was placed on the patients' perception of their own emotions and not on the recognition of emotions in others. Severity of depression was assessed by the Beck Depression Inventory. RESULTS: Eating disordered patients and DP reported less anger than healthy controls-independent of the severity of depression. In addition, DP showed increased levels of disgust when confronted with anger stimuli. Happiness was rated less in EDP and DP, which was associated with severity of depression. There were no differences between the EDP subgroups bulimia nervosa and anorexia nervosa. CONCLUSION: Eating disordered patients and DP showed alterations of emotional perception of anger, an emotion which is closely linked to interpersonal difficulties. Alterations in emotional perception of EDP and DP might be due to more general emotion regulation disturbances. In order to detect more subtle differences between psychiatric subgroups, more sophisticated investigation tools are needed. Increased disgust ratings in DP merit further investigation.

State or trait: the neurobiology of anorexia nervosa - contributions of a functional magnetic resonance imaging study.

BACKGROUND: The understanding of the cerebral neurobiology of anorexia nervosa (AN) with respect to state- versus trait-related abnormalities is limited. There is evidence of restitution of structural brain alterations with clinical remission. However, with regard to functional brain abnormalities, this issue has not yet been clarified. METHODS: We compared women with AN (n = 31), well-recovered female participants (REC) (n = 18) and non-patients (NP) (n = 27) cross-sectionally. Functional magnetic resonance imaging was performed to compare neural responses to food versus non-food images. Additionally, affective ratings were assessed. RESULTS: Functional responses and affective ratings did not differ between REC and NP, even when applying lenient thresholds for the comparison of neural responses. Comparing REC and AN, the latter showed lower valence and higher arousal ratings for food stimuli, and neural responses differed with lenient thresholds in an occipital region. CONCLUSIONS: The data are in line with some previous findings and suggest restitution of cerebral function with clinical recovery. Furthermore, affective ratings did not differ from NP. These results need to be verified in intra-individual longitudinal studies.

There is abundant evidence of structural and functional brain alterations during the acute stage of anorexia nervosa (AN), although affected brain areas differ based on various study methodologies. Meanwhile, investigations indicate that brain structure normalizes with weight and clinical restitution. The current cross-sectional investigation examines acutely ill AN patients, healthy controls, i.e. non-patients (NP) and well-recovered individuals (REC), with respect to brain function. Functional cerebral responses of participants exposed to food pictures were investigated. Neither in terms of function nor emotional experience of food stimuli, the REC differed from the NP group. This study points to brain function normalizing with clinical and weight restoration, which should be verified in intra-individual longitudinal studies.

Amygdala hyperreactivity in restrictive anorexia nervosa.

Functional imaging studies had often investigated heterogeneous samples of anorexia nervosa (AN) patients with varying paradigms and methodologies that had resulted in divergent results. The present study aimed to examine these issues by studying a well-defined sample of restrictive AN patients with a disorder-specific paradigm which had been used previously. Subjects showed increased blood oxygen level dependent responses of the cingulate, frontal, insular and parietal cortices. Group comparisons demonstrated increased activity of the right amygdala in the sample of restrictive AN patients. Our results are in support of other recently published functional imaging studies and point to a pivotal role of the right amygdala in AN. Signals of the midcingulum were reduced in comparison to healthy controls. The constellation of increased activity of the amygdala and decreased activity of the cingulate cortex likely represents parts of a negative feedback loop of emotional processing. Disgust ratings correlated with the amygdala signal negatively, which points to the complex role of this structure within eating disorders.

Magnetic resonance spectroscopy of the anterior cingulate cortex in eating disorders.

The anterior cingulate cortex plays a key role in eating disorders (ED), but it remains an open question whether there are deviations of the neurochemistry of this region in patients with ED. Seventeen adult female patients with ED (10 with bulimia nervosa, 7 with anorexia nervosa) were compared to 14 matched female healthy controls using single voxel magnetic resonance spectroscopy of the anterior cingulate cortex. Group comparisons did not reveal any differences between patients and controls, but a positive correlation between glutamate and myo-inositol signals with "drive for thinness" in patients with bulimia nervosa was found in exploratory correlation analyses.

Frontocingular dysfunction in bulimia nervosa when confronted with disease-specific stimuli.

OBJECTIVE: Bulimia nervosa (BN) is characterized by dysregulation of impulse control, in other words, uncontrolled eating. Functional neuroimaging studies have been sparse and have used variable methodologies. METHOD: Thirteen medication-free female BN patients and 13 female healthy controls were investigated by functional magnetic resonance imaging using a disease-specific food paradigm. Stimuli were rated after the scanning procedure. RESULTS: Bulimia nervosa patients showed increased fear ratings and a trend for increased disgust. Magnetic resonance imaging data of 10 BN patients could be analysed. Three BN patients had to be excluded from the analysis because of minimal blood oxygen level dependent signals. Compared with healthy controls, BN patients showed less activation of the anterior cingulate cortex, which extended into the lateral prefrontal cortex. Furthermore, the right temporal pole showed decreased reactivity. DISCUSSION: This study substantiates a key role of lateral prefrontal dysfunction in BN, a brain region involved in impulse control. Furthermore, the anterior cingulate cortex, which plays a key role in emotion processing, is dysfunctional. A major limitation of this study is the small sample size.

Emotional perception in eating disorders.

OBJECTIVE: It remains an open question whether there are basic emotional perception and emotional processing deficits in eating disorders (ED). The aim of this study was to explore deficits in emotional perception in restrictive anorexia nervosa (AN-R) and bulimia nervosa (BN), using visual emotional stimuli. METHOD: Thirty-four patients with ED (19 with BN and 15 with AN-R) were compared with 25 controls. Visual stimuli from the international affective picture system were used. RESULTS: Patients with AN-R showed increased fear when confronted with stimuli containing anger, whereas patients with BN showed a tendency towards decreased fear. There were no other fundamental differences in the emotional perception of fear, happiness, sadness, and anger. DISCUSSION: The finding of increased fear when exposed to the emotion of anger might be attributed to introversion and conflict avoidance of anorectic patients. No other basic deficiency of emotional perception was found.