title: Structural but not functional neuroplasticity one year after effective cognitive behaviour therapy for social anxiety disorder.
abstract: Effective psychiatric treatments ameliorate excessive anxiety and induce neuroplasticity immediately after the intervention, indicating that emotional components in the human brain are rapidly adaptable. Still, the interplay between structural and functional neuroplasticity is poorly understood, and studies of treatment-induced long-term neuroplasticity are rare. Functional and structural magnetic resonance imaging (using 3T MRI) was performed in 13 subjects with social anxiety disorder on 3 occasions over 1year. All subjects underwent 9 weeks of Internet-delivered cognitive behaviour therapy in a randomized cross-over design and independent assessors used the Clinically Global Impression-Improvement (CGI-I) scale to determine treatment response. Gray matter (GM) volume, assessed with voxel-based morphometry, and functional blood-oxygen level-dependent (BOLD) responsivity to self-referential criticism were compared between treatment responders and non-responders using 2×2 (group×time; pretreatment to follow-up) ANOVA. At 1-year follow-up, 7 (54%) subjects were classified as CGI-I responders. Left amygdala GM volume was more reduced in responders relative to non-responders from pretreatment to 1-year follow-up (Z=3.67, Family-Wise Error corrected p=0.02). In contrast to previous short-term effects, altered BOLD activations to self-referential criticism did not separate responder groups at follow-up. The structure and function of the amygdala changes immediately after effective psychological treatment of social anxiety disorder, but only reduced amygdala GM volume, and not functional activity, is associated with a clinical response 1year after CBT.
authors.affiliation: Department of Behavioural Sciences and Learning, Psychology, Linköping University, Linköping, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden. Electronic address: kristoffer.nt.mansson@liu.se.
authors.forename: Kristoffer N T
authors.initials: KNT
authors.lastname: Månsson
authors.affiliation: Aging Research Center, Karolinska Institutet, Stockholm, Sweden; Umeå Centre for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden.
authors.forename: Alireza
authors.initials: A
authors.lastname: Salami
authors.affiliation: Department of Psychology, Stockholm University, Stockholm, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Carlbring
authors.affiliation: Umeå Centre for Functional Brain Imaging (UFBI), Umeå University, Umeå, Sweden; Centre Demographic and Aging Research (CEDAR), Umeå University, Umeå, Sweden; Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Denmark.
authors.forename: C-J
authors.initials: CJ
authors.lastname: Boraxbekk
authors.affiliation: Department of Behavioural Sciences and Learning, Psychology, Linköping University, Linköping, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Andersson
authors.affiliation: Department of Psychology, Uppsala University, Uppsala, Sweden.
authors.forename: Tomas
authors.initials: T
authors.lastname: Furmark
mesh_terms: D000328:Adult; D000679:Amygdala / Q000502:physiology; D001284:Atrophy / Q000473:pathology; D015928:Cognitive Behavioral Therapy; D018592:Cross-Over Studies; D005260:Female; D066128:Gray Matter / Q000473:pathology* / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D059906:Neuroimaging; D009473:Neuronal Plasticity / Q000502:physiology*; D000072861:Phobia, Social / Q000503:physiopathology* / Q000628:therapy; D055815:Young Adult
keywords: Amygdala; Cognitive behavior therapy; Long-term; Neuroplasticity; Social anxiety disorder