title: Towards mapping the brain connectome in depression: functional connectivity by perfusion SPECT.
abstract: Several studies have demonstrated altered brain functional connectivity in the resting state in depression. However, no study has investigated interregional networking in patients with persistent depressive disorder (PDD). The aim of this study was to assess differences in brain perfusion distribution and connectivity between large groups of patients and healthy controls. Participants comprised 91 patients with PDD and 65 age- and sex-matched healthy controls. Resting state perfusion was investigated by single photon emission computed tomography, and group differences were assessed by Statistical Parametric Mapping. Brain connectivity was explored through a voxel-wise interregional correlation analysis using as covariate of interest the normalized values of clusters of voxels in which perfusion differences were found in group analysis. Significantly increased regional brain perfusion distribution covering a large part of the cerebellum was observed in patients as compared with controls. Patients showed a significant negative functional connectivity between the cerebellar cluster and caudate, bilaterally. This study demonstrated inverse relative perfusion between the cerebellum and the caudate in PDD. Functional uncoupling may be associated with a dysregulation between the role of the cerebellum in action control and of the caudate in action selection, initiation and decision making in the patients. The potential impact of the resting state condition and the possibility of mitochondrial impairment are discussed.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Järva Psychiatric Out-patient Clinic, Stockholm, Sweden.
authors.forename: Ann
authors.initials: A
authors.lastname: Gardner
authors.affiliation: Section of Imaging Physics, Solna Nuclear Medicine, Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Disa
authors.initials: D
authors.lastname: Åstrand
authors.affiliation: Section of Imaging Physics, Department of Hospital Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Johanna
authors.initials: J
authors.lastname: Öberg
authors.affiliation: Department of Nuclear Medicine, Karolinska Hospital, Stockholm, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Jacobsson
authors.affiliation: Section of Imaging Physics, Solna Nuclear Medicine, Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Cathrine
authors.initials: C
authors.lastname: Jonsson
authors.affiliation: Department of Nuclear Medicine, Karolinska Hospital, Stockholm, Sweden.
authors.forename: Stig
authors.initials: S
authors.lastname: Larsson
authors.affiliation: Department of Nuclear Medicine, Karolinska Hospital, Stockholm, Sweden; Institute of Cognitive Sciences and Technologies, Consiglio Nazionale delle Ricerche (CNR), Rome, Italy. Electronic address: marco.pagani@istc.cnr.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Pagani
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002421:Caudate Nucleus / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002531:Cerebellum / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002908:Chronic Disease; D063132:Connectome / Q000379:methods*; D003863:Depression / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology; D003866:Depressive Disorder / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011619:Psychotropic Drugs / Q000627:therapeutic use; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D011619:Psychotropic Drugs
keywords: Caudate; Cerebellum; Chronic depression; Mitochondrial impairment; Persistent depressive disorder