title: A single dose of mirtazapine attenuates neural responses to self-referential processing.
abstract: Increased self-focus is a core factor in the psychopathology of depression. Cortical midline structures (CMS) are implicated in the neurobiology of self, depression and antidepressant treatment response. Mirtazapine, an antidepressant that increases serotonin and norepinephrine release, enhances processing of positive and attenuates processing of negative emotional information in healthy volunteers after a single dose. These early changes, which are opposite to the negative information bias in depression, may be important for the therapeutic effect of mirtazapine. It nevertheless remains unresolved whether/how mirtazapine specifically influences processing of self-referential emotional information.Half of the healthy volunteers (n=15/30) received a single dose of mirtazapine, in an open-label design, two hours before functional magnetic resonance imaging (fMRI), and the other half was scanned as a control group without medication. During fMRI the participants categorized positive and negative self-referential adjectives.Mirtazapine attenuated responses to self-referential processing in the medial prefrontal cortex and the anterior cingulate cortex. Mirtazapine further decreased responses to positive self-referential processing in the posterior cingulate cortex and parietal cortex.These decreased responses of the CMS suggest that mirtazapine may rapidly improve the ability of the CMS to down-regulate self-referential processing. In depressed patients, this could lead to decreased self-focus and rumination, contributing to the antidepressant effect.
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland.
authors.forename: Emma
authors.initials: E
authors.lastname: Komulainen
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland.
authors.forename: Roope
authors.initials: R
authors.lastname: Heikkilä
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland.
authors.forename: Katarina
authors.initials: K
authors.lastname: Meskanen
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland Aalto NeuroImaging, Aalto University, Espoo, Finland Aalto University, School of Science, Department of Neuroscience and Biomedical Engineering, Espoo, Finland.
authors.forename: Tuukka T
authors.initials: TT
authors.lastname: Raij
authors.affiliation: Aalto University, School of Science, Department of Neuroscience and Biomedical Engineering, Espoo, Finland Turku PET Centre and Department of Psychology, University of Turku, Turku, Finland.
authors.forename: Lauri
authors.initials: L
authors.lastname: Nummenmaa
authors.affiliation: University of Helsinki, Institute of Behavioural Sciences, Helsinki, Finland Folkhälsan Research Center, Helsinki, Finland.
authors.forename: Jari
authors.initials: J
authors.lastname: Lahti
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland National Institute of Health and Welfare, Department of Mental Health and Substance Abuse Services, Helsinki, Finland.
authors.forename: Pekka
authors.initials: P
authors.lastname: Jylhä
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Melartin
authors.affiliation: University Department of Psychiatry, Oxford, UK.
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Harmer
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland National Institute of Health and Welfare, Department of Mental Health and Substance Abuse Services, Helsinki, Finland.
authors.forename: Erkki
authors.initials: E
authors.lastname: Isometsä
authors.affiliation: University of Helsinki and Helsinki University Hospital, Psychiatry, Helsinki, Finland Vaasa Hospital District, Department of Psychiatry, Vaasa, Finland jesper.ekelund@helsinki.fi.
authors.forename: Jesper
authors.initials: J
authors.lastname: Ekelund
mesh_terms: D000293:Adolescent; D000328:Adult; D000929:Antidepressive Agents, Tricyclic / Q000008:administration & dosage / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D003863:Depression / Q000188:drug therapy / Q000503:physiopathology; D004644:Emotions / Q000187:drug effects*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008803:Mianserin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D000078785:Mirtazapine; D055815:Young Adult
chemical_list: D000929:Antidepressive Agents, Tricyclic; D008803:Mianserin; D000078785:Mirtazapine
keywords: Antidepressant; emotions; fMRI; mirtazapine; self-referential processing