Grey matter abnormalities within cortico-limbic-striatal circuits in acute and weight-restored anorexia nervosa patients
ABSTRACT Functional disturbances within cortico-striatal control systems have been implicated in the psychobiology (i.e. impaired cognitive-behavioral flexibility, perfectionist personality) of anorexia nervosa. The aim of the present study was to investigate the morphometry of brain regions within cortico-striatal networks in acute anorexia nervosa (AN) as well as long-term weight-restored anorexia nervosa (AN-WR) patients. A total of 39 participants: 12 AN, 13 AN-WR patients, and 14 healthy controls (HC) underwent high-resolution, T1-weighted magnetic resonance imaging (MRI), a cognitive-behavioral flexibility task, and a psychometric assessment. Group differences in local grey matter volume (GMV) were analyzed using whole brain voxel-based morphometry (VBM) and brain-atlas based automatic volumetry computation (IBASPM). Individual differences in total GMV were considered as a covariate in all analyses. In the regional brain morphometry, AN patients, as compared to HC, showed decreased GMVs (VBM and volumetry) in the anterior cingulate cortex (ACC), the supplementary motor area (SMA), and in subcortical regions (amygdala, putamen: VBM only). AN-WR compared to HC showed decreased GMV (VBM and volumetry) in the ACC and SMA, whereas GMV of the subcortical region showed no differences. The findings of the study suggest that structural abnormalities of the ACC and SMA were independent of the disease stage, whereas subcortical limbic-striatal changes were state dependent.
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- "Neuroimaging research has identified a variety of neuroanatomical substrates of ED pathophysiology. For example, on structural imaging, ED patients show reductions in gray matter volume in regions involved in reward, impulse control, and emotion regulation: the caudate nucleus, ventral striatum (VS), anterior cingulate (ACC) and orbitofrontal cortex (OFC) (Friederich et al., 2012; Schäfer et al., 2010; Titova et al., 2013; Van den Eynde et al., 2012). Likewise, functional magnetic resonance imaging (fMRI) studies in ED reveal abnormal patterns of resting-state connectivity in the default-mode network (Cowdrey et al., 2014) and other intrinsic brain networks incorporating the ACC and insula (Amianto et al., 2013). "
ABSTRACT: Background Conventional treatments for eating disorders are associated with poor response rates and frequent relapse. Novel treatments are needed, in combination with markers to characterize and predict treatment response. Here, resting-state functional magnetic resonance imaging (rs-fMRI) was used to identify predictors and correlates of response to repetitive transcranial magnetic stimulation (rTMS) of the dorsomedial prefrontal cortex (dmPFC) at 10 Hz for eating disorders with refractory binge/purge symptomatology. Methods 28 subjects with anorexia nervosa, binge−purge subtype or bulimia nervosa underwent 20–30 sessions of 10 Hz dmPFC rTMS. rs-fMRI data were collected before and after rTMS. Subjects were stratified into responder and nonresponder groups using a criterion of ≥50% reduction in weekly binge/purge frequency. Neural predictors and correlates of response were identified using seed-based functional connectivity (FC), using the dmPFC and adjacent dorsal anterior cingulate cortex (dACC) as regions of interest. Results 16 of 28 subjects met response criteria. Treatment responders had lower baseline FC from dmPFC to lateral orbitofrontal cortex and right posterior insula, and from dACC to right posterior insula and hippocampus. Responders had low baseline FC from the dACC to the ventral striatum and anterior insula; this connectivity increased over treatment. However, in nonresponders, frontostriatal FC was high at baseline, and dmPFC-rTMS suppressed FC in association with symptomatic worsening. Conclusions Enhanced frontostriatal connectivity was associated with responders to dmPFC-rTMS for binge/purge behavior. rTMS caused paradoxical suppression of frontostriatal connectivity in nonresponders. rs-fMRI could prove critical for optimizing stimulation parameters in a future sham-controlled trial of rTMS in disordered eating.
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- "However, only a few studies have investigated brain structure in patients before and after weight restoration. Some studies report that the brain normalizes completely at both a global and regional level after weight restoration (Wagner et al., 2006) while other studies have reported nonreversible regional changes in gray matter in the anterior cingulate cortex (Friederich et al., 2012; Muhlau et al., 2007), supplementary motor area (Friederich et al., 2012), and precuneus (Joos et al., 2011). Collectively, these latter studies suggest that gray matter is more affected than white matter in patients with AN, and gray matter reductions may be only partially reversible. "
ABSTRACT: Structural brain changes associated with starvation and clinical measurements were explored in four females with anorexia nervosa with different clinical course, at baseline and 1-year follow-up, after receiving intensive inpatient treatment at a specialized eating disorder unit. Global volume alterations were associated with weight changes. Regional volume alterations were also associated with weight changes, with the largest changes occurring in the nucleus accumbens, amygdala, pallidum, and putamen. Largest changes in cortical thickness occurred in the frontal and temporal lobes. The results are preliminary; however, they show that fluctuations in weight are associated with brain volume alterations, especially gray matter. We suggest that these parts of the brain are vulnerable to starvation and malnutrition, and could be a part of the pathophysiology of AN.Neurocase 01/2014; 21(2). DOI:10.1080/13554794.2013.878728 · 1.38 Impact Factor
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- "No group differences in grey matter . Friederich et al . ( 2012 ) 12 AN ( 6 AN - R , 6 AN - BP ) , 13 rec - AN , 14 HC All participants were tested once . AN and rec - AN vs HC : decreased grey matter volume in ACC and supplementary motor area . AN vs HC : decreased grey matter volume in amygdala and putamen . AN vs rec - AN : reduced grey matter volume in the left amygdala , putamen and bilateral i"
ABSTRACT: Objective:Recent advances in neuroimaging techniques have enabled a better understanding of the neurobiological underpinnings of anorexia nervosa (AN). The aim of this paper was to summarise our current understanding of the neurobiology of AN.Methods:The literature was searched using the electronic databases PubMed and Google Scholar, and by additional hand searches through reference lists and specialist eating disorders journals. Relevant studies were included if they were written in English, only used human participants, had a specific AN group, used clinical populations of AN, group comparisons were reported for AN compared to healthy controls and not merely AN compared to other eating disorders or other psychiatric groups, and were not case studies.Results:The systematic review summarises a number of structural and functional brain differences which are reported in individuals with AN, including differences in neurotransmitter function, regional cerebral blood flow, glucose metabolism, volumetrics and the blood oxygen level dependent response.Conclusion:Several structural and functional differences have been reported in AN, some of which reverse and others which persist following weight restoration. These findings have important implications for our understanding of the neurobiological underpinnings of AN, and further research in this field may provide new direction for the development of more effective treatments.Australian and New Zealand Journal of Psychiatry 11/2013; 48. DOI:10.1177/0004867413509693 · 3.77 Impact Factor