title: Experience of social discrimination correlates with neurometabolism: a pilot study in heroin addicts.
abstract: Experimental social neuroscience has shown that being socially excluded is processed in the anterior cingulate cortex (ACC). We hypothesize that a chronic form of social exclusion resembling one aspect of social stigmatization is associated with altered neural plasticity reflected by neurometabolic alterations in the ACC. To test this hypothesis, a highly stigmatized patient group of heroin addicts (N = 15) during opiate maintenance therapy rated a questionnaire about being stigmatized, and neurometabolic markers in the ACC were determined using (1)H MR spectroscopy. We found a negative correlation between discrimination experience and N-acetylaspartate (NAA), indicating attenuated neuron functioning in the anterior cingulate cortex in those patients reporting high discrimination experience. Furthermore, perceived stigmatization showed an association with anxiety that was mediated by NAA. Although the correlative analysis cannot give evidence for a causal relationship, the relation of NAA in the ACC and discrimination experience indicates a malfunction of the neural system involved in cognitive control over emotionally relevant social stimuli in discrimination reporting heroin addicts. Further research is needed to elucidate factors associated with chronic stigmatization.
authors.affiliation: Department of Addictive Behaviour and Addiction Medicine, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, P. O. box 12 21 20, 68072 Mannheim, Germany. ulrich.frischknecht@zi-mannheim.de
authors.forename: Ulrich
authors.initials: U
authors.lastname: Frischknecht
authors.forename: Derik
authors.initials: D
authors.lastname: Hermann
authors.forename: Milena
authors.initials: M
authors.lastname: Heinrich
authors.forename: Mareen
authors.initials: M
authors.lastname: Hoerst
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Weber-Fahr
authors.forename: Sabine
authors.initials: S
authors.lastname: Vollstädt-Klein
authors.forename: Falk
authors.initials: F
authors.lastname: Kiefer
authors.forename: Karl
authors.initials: K
authors.lastname: Mann
authors.forename: Gabriele
authors.initials: G
authors.lastname: Ende
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D005260:Female; D006179:Gyrus Cinguli / Q000378:metabolism* / Q000473:pathology; D006556:Heroin Dependence / Q000150:complications / Q000473:pathology / Q000523:psychology; D006801:Humans; D016014:Linear Models; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D063508:Social Discrimination / Q000523:psychology*; D057545:Social Stigma; D011795:Surveys and Questionnaires; D014316:Tritium
chemical_list: D014316:Tritium; D001224:Aspartic Acid; C000179:N-acetylaspartate