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A debate on current eating disorder diagnoses in light of neurobiological findings: is it time for a spectrum model?

Brooks SJ, Rask-Andersen M, Benedict C, Schiöth HB - BMC Psychiatry (2012)

Bottom Line: Sixty percent of eating disorders do not meet criteria for anorexia- or bulimia nervosa, as defined by the Diagnostic and Statistical Manual version 4 (DSM-IV).Instead they are diagnosed as 'eating disorders not otherwise specified' (EDNOS).Here we debate the classification issues, and discuss how brain imaging and genetic discoveries might be interwoven into a model of eating disorders to provide better classification and treatment.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Neuroscience, University of Uppsala, Box 593, Uppsala, Sweden. samantha.brooks@neuro.uu.se

ABSTRACT

Background: Sixty percent of eating disorders do not meet criteria for anorexia- or bulimia nervosa, as defined by the Diagnostic and Statistical Manual version 4 (DSM-IV). Instead they are diagnosed as 'eating disorders not otherwise specified' (EDNOS). Discrepancies between criteria and clinical reality currently hampering eating disorder diagnoses in the DSM-IV will be addressed by the forthcoming DSM-V. However, future diagnoses for eating disorders will rely on current advances in the fields of neuroimaging and genetics for classification of symptoms that will ultimately improve treatment.

Discussion: Here we debate the classification issues, and discuss how brain imaging and genetic discoveries might be interwoven into a model of eating disorders to provide better classification and treatment. The debate concerns: a) current issues in the classification of eating disorders in the DSM-IV, b) changes proposed for DSM-V, c) neuroimaging eating disorder research and d) genetic eating disorder research.

Summary: We outline a novel evidence-based 'impulse control' spectrum model of eating disorders. A model of eating disorders is proposed that will aid future diagnosis of symptoms, coinciding with contemporary suggestions by clinicians and the proposed changes due to be published in the DSM-V.

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Related in: MedlinePlus

Imbalanced PFC-mesolimbic convergence on the insular cortex in those with eating disorders.
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Figure 2: Imbalanced PFC-mesolimbic convergence on the insular cortex in those with eating disorders.

Mentions: A commonality between all ED subtypes is seemingly dysregulated neural activation in response to food stimuli in the parietal cortex, and the insular cortex in the temporal lobe, regions associated with somatosensory perception and interoceptive awareness [25,38]. One might argue that somatosensory perception occurs via a balance between basic bottom-up arousal systems, and higher order top-down cognitive evaluations. Against this background, it is proposed that an excessive activation at one or other extremes (e.g. restraint versus binge eating systems) in those with eating disorders causes an imbalanced convergence on these somatosensory brain regions, associated with dysfunctional processing of the body state (inexorably linked to body image distortions). See Figure 2. Additionally, hyperactivation of the amygdala is often seen across ED diagnoses [39,40] and likely leads to anxiety experienced by most ED sufferers regardless of subtype. Emotional experiences that derive from somatosensory states can be positively or negatively arousing (e.g. pleasant feelings during appetite satisfaction versus unpleasant anxiety and anger) and are linked to areas of the ‘temporoparietal junction’ that are involved in creating a sense of self-control over one’s actions [41]. It has long been established that people with ED have problems identifying and expressing their emotions [42], a core symptom known as alexithymia, which has been further demonstrated in recent neuropsychological studies [43,44]. An imbalanced regulatory neural circuit between the PFC and mesolimbic regions likely hampers a healthy orchestration of these systems, leading to a ‘rate-limiting’ defect in the insula [45] and other somatosensory regions that normally provide a solid sense of ‘emotional self’ (See Figure 2).


A debate on current eating disorder diagnoses in light of neurobiological findings: is it time for a spectrum model?

Brooks SJ, Rask-Andersen M, Benedict C, Schiöth HB - BMC Psychiatry (2012)

Imbalanced PFC-mesolimbic convergence on the insular cortex in those with eating disorders.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3475111&req=5

Figure 2: Imbalanced PFC-mesolimbic convergence on the insular cortex in those with eating disorders.
Mentions: A commonality between all ED subtypes is seemingly dysregulated neural activation in response to food stimuli in the parietal cortex, and the insular cortex in the temporal lobe, regions associated with somatosensory perception and interoceptive awareness [25,38]. One might argue that somatosensory perception occurs via a balance between basic bottom-up arousal systems, and higher order top-down cognitive evaluations. Against this background, it is proposed that an excessive activation at one or other extremes (e.g. restraint versus binge eating systems) in those with eating disorders causes an imbalanced convergence on these somatosensory brain regions, associated with dysfunctional processing of the body state (inexorably linked to body image distortions). See Figure 2. Additionally, hyperactivation of the amygdala is often seen across ED diagnoses [39,40] and likely leads to anxiety experienced by most ED sufferers regardless of subtype. Emotional experiences that derive from somatosensory states can be positively or negatively arousing (e.g. pleasant feelings during appetite satisfaction versus unpleasant anxiety and anger) and are linked to areas of the ‘temporoparietal junction’ that are involved in creating a sense of self-control over one’s actions [41]. It has long been established that people with ED have problems identifying and expressing their emotions [42], a core symptom known as alexithymia, which has been further demonstrated in recent neuropsychological studies [43,44]. An imbalanced regulatory neural circuit between the PFC and mesolimbic regions likely hampers a healthy orchestration of these systems, leading to a ‘rate-limiting’ defect in the insula [45] and other somatosensory regions that normally provide a solid sense of ‘emotional self’ (See Figure 2).

Bottom Line: Sixty percent of eating disorders do not meet criteria for anorexia- or bulimia nervosa, as defined by the Diagnostic and Statistical Manual version 4 (DSM-IV).Instead they are diagnosed as 'eating disorders not otherwise specified' (EDNOS).Here we debate the classification issues, and discuss how brain imaging and genetic discoveries might be interwoven into a model of eating disorders to provide better classification and treatment.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Neuroscience, University of Uppsala, Box 593, Uppsala, Sweden. samantha.brooks@neuro.uu.se

ABSTRACT

Background: Sixty percent of eating disorders do not meet criteria for anorexia- or bulimia nervosa, as defined by the Diagnostic and Statistical Manual version 4 (DSM-IV). Instead they are diagnosed as 'eating disorders not otherwise specified' (EDNOS). Discrepancies between criteria and clinical reality currently hampering eating disorder diagnoses in the DSM-IV will be addressed by the forthcoming DSM-V. However, future diagnoses for eating disorders will rely on current advances in the fields of neuroimaging and genetics for classification of symptoms that will ultimately improve treatment.

Discussion: Here we debate the classification issues, and discuss how brain imaging and genetic discoveries might be interwoven into a model of eating disorders to provide better classification and treatment. The debate concerns: a) current issues in the classification of eating disorders in the DSM-IV, b) changes proposed for DSM-V, c) neuroimaging eating disorder research and d) genetic eating disorder research.

Summary: We outline a novel evidence-based 'impulse control' spectrum model of eating disorders. A model of eating disorders is proposed that will aid future diagnosis of symptoms, coinciding with contemporary suggestions by clinicians and the proposed changes due to be published in the DSM-V.

Show MeSH
Related in: MedlinePlus