White matter microstructure in habit and reward circuits in anorexia nervosa: Insights from a neurite orientation dispersion and density imaging study

Abstract

doi: medRxiv preprint NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.

Habits and Persistent Food Restriction in Patients with Anorexia Nervosa: A Scoping Review

“…The evaluation of habits related to food restriction in individuals with AN was based on distinct methods (Figure 3), namely: (a) scales (n = 4) [9,27,39,40], (b) neuroimaging (n = 11) [26,[28][29][30][31]33,35,38,[42][43][44], (c) experimental and behavioural tasks (n = 3) [15,32,34], and (d) neuroimaging and experimental and behavioural tasks (n = 2) [36,37].…”

“…Samples ranging from 12 [44] to 54 [35] individuals comprised the control groups. Most studies (n = 16) included exclusively female individuals [9,15,[26][27][28][29]31,[33][34][35][37][38][39][42][43][44] and adolescent and adult participants (n = 9) [27,29,31,34,37,38,40,42,43]. The white race was predominant in studies that evaluated this demographic variable (Table S2 in Supplementary S3).…”

“…Participants with AN were recruited in hospitals and or outpatient services specialised in the treatment of eating disorders (n = 17) [9,[26][27][28][29][30][31][32][33][34][35]37,39,40,[42][43][44] and in other different catchment spaces [15,38] (Table S2 in Supplementary S3). Diagnostic confirmation was performed using different tools, with a predominance of the Eating Disorder Assessment for DSM-5 (EDA-5) [9,28,31,38,39] (n = 5) followed by the Eating Disorder Examination (EDE) (n = 4) [15,26,30,43] and the Structured Interview for Anorexia and Bulimia Disorders (SIAB-EX) (n= 3) [27,37,42] (Table S2 in Supplementary S3). To assess the symptomatology of AN's severity, most studies adopted the Eating Disorder Examination Questionnaire (EDE-Q) (n = 10) [9,15,28,31,[33][34][35]38,39,43], followed by the Eating Disorders Inventory-2 (EDI-2) (n = 4) [27,…”

“…Diagnostic confirmation was performed using different tools, with a predominance of the Eating Disorder Assessment for DSM-5 (EDA-5) [9,28,31,38,39] (n = 5) followed by the Eating Disorder Examination (EDE) (n = 4) [15,26,30,43] and the Structured Interview for Anorexia and Bulimia Disorders (SIAB-EX) (n= 3) [27,37,42] (Table S2 in Supplementary S3). To assess the symptomatology of AN's severity, most studies adopted the Eating Disorder Examination Questionnaire (EDE-Q) (n = 10) [9,15,28,31,[33][34][35]38,39,43], followed by the Eating Disorders Inventory-2 (EDI-2) (n = 4) [27,32,37,42], the Yale-Brown-Cornell Eating Disorder Scale (YBC-EDS) (n = 3) [26,30,31], and the Three-Factor Eating Questionnaire (TFEQ) (n = 3) [43,44,51].…”

Assessing midbrain neuromelanin and its relationship to reward learning in anorexia nervosa: Stage 1 of a registered report

“…Reduced gray matter volume is evident in key nodes of the brain's reward circuit, including the ventral striatum and orbitofrontal cortex (OFC) (Frank et al., 2013 ; Titova et al., 2013 ), and aberrant connectivity of white matter tracts in reward systems has also been observed (Cha et al., 2016 ; Via et al., 2014 ). In white matter tracts connecting key reward circuit regions of the ventral tegmental area (VTA) and the nucleus accumbens (NAc), we previously found in adolescents with AN abnormal microstructure in the form of reduced neurite and myelin density and reduced orientation dispersion (Murray et al., 2023 ). Further, orientation dispersion in this tract—a measure of tract “fanning,” which, in general, is negatively correlated with fractional anisotropy (FA) (Zhang et al., 2012 )—was associated with subjective reward responsiveness.…”