title: Hippocampal structural and functional changes associated with electroconvulsive therapy response.
abstract: Previous animal models and structural imaging investigations have linked hippocampal neuroplasticity to electroconvulsive therapy (ECT) response, but the relationship between changes in hippocampal volume and temporal coherence in the context of ECT response is unknown. We hypothesized that ECT response would increase both hippocampal resting-state functional magnetic resonance imaging connectivity and hippocampal volumes. Patients with major depressive disorder (n=19) were scanned before and after the ECT series. Healthy, demographically matched comparisons (n=20) were scanned at one-time interval. Longitudinal changes in functional connectivity of hippocampal regions and volumes of hippocampal subfields were compared with reductions in ratings of depressive symptoms. Right hippocampal connectivity increased (normalized) after the ECT series and correlated with depressive symptom reduction. Similarly, the volumes of the right hippocampal cornu ammonis (CA2/3), dentate gyrus and subiculum regions increased, but the hippocampal subfields were unchanged relative to the comparison group. Connectivity changes were not evident in the left hippocampus, and volume changes were limited to the left CA2/3 subfields. The laterality of the right hippocampal functional connectivity and volume increases may be related to stimulus delivery method, which was predominately right unilateral in this investigation. The findings suggested that increased hippocampal functional connectivity and volumes may be biomarkers for ECT response.
authors.affiliation: Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA.
authors.forename: C C
authors.initials: CC
authors.lastname: Abbott
authors.affiliation: Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA.
authors.forename: T
authors.initials: T
authors.lastname: Jones
authors.affiliation: Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA.
authors.forename: N T
authors.initials: NT
authors.lastname: Lemke
authors.affiliation: Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA.
authors.forename: P
authors.initials: P
authors.lastname: Gallegos
authors.affiliation: 1] Division of Brain Stimulation and Neurophysiology, Department of Psychiatry and Behavioral Sciences, Duke University School of Medicine, Durham, NC, USA [2] Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: McClintock
authors.affiliation: Mind Research Network, Albuquerque, NM, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Mayer
authors.affiliation: Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA.
authors.forename: J
authors.initials: J
authors.lastname: Bustillo
authors.affiliation: 1] Department of Psychiatry, Center for Psychiatric Research MSC11 6035, University of New Mexico School of Medicine, Albuquerque, NM, USA [2] Mind Research Network, Albuquerque, NM, USA [3] Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM, USA.
authors.forename: V D
authors.initials: VD
authors.lastname: Calhoun
mesh_terms: D000368:Aged; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D004565:Electroconvulsive Therapy / Q000379:methods; D005260:Female; D006624:Hippocampus / Q000033:anatomy & histology / Q000473:pathology* / Q000502:physiology / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009473:Neuronal Plasticity / Q000502:physiology*; D016896:Treatment Outcome