Journal of Neuroscience Research
2026
Stephanie N Njau, Artemis Zavaliangos-Petropulu, Shantanu Joshi et al.
Ketamine has emerged as a highly effective intervention for treatment-resistant depression (TRD). Though it acts as a non-competitive antagonist of excitatory N-methyl-D-aspartate receptors (NMDAR), widely expressed in the brain, including on inhibitory γ-aminobutyric acid (GABA)-ergic cells, the mechanisms of its antidepressant action are less clear. To investigate the links between glutamate...
Imaging neuroscience (Cambridge, Mass.)
2025
Brandon Taraku, Jason S Nomi, Artemis Zavaliangos-Petropulu et al.
Ketamine produces fast-acting antidepressant effects in treatment-resistant depression (TRD). Prior studies have shown altered functional dynamics between brain networks in major depression. We thus sought to determine whether functional brain network dynamics are modulated by ketamine therapy in TRD. Participants with TRD (n = 58, mean age = 40.7 years, female = 48.3%) completed resting-state...
Brain and Behavior
June 1, 2024
Brandon Taraku, Joana R Loureiro, Ashish K Sahib et al.
11 citations
Major depressive disorder (MDD) is associated with dysfunctional reward processing, which involves functional circuitry of the habenula (Hb) and nucleus accumbens (NAc). Since ketamine elicits rapid antidepressant and antianhedonic effects in MDD, this study sought to investigate how serial ketamine infusion (SKI) treatment modulates static and dynamic functional connectivity (FC) in Hb and NAc...
medRxiv Preprint Server
December 1, 2023
Brandon Taraku, Joana R Loureiro, Ashish K Sahib et al.
1 citation
preprint
Dysfunctional reward processing in major depressive disorder (MDD) involves functional circuitry of the habenula (Hb) and nucleus accumbens (NAc). Ketamine elicits rapid antidepressant and alleviates anhedonia in MDD. To clarify how ketamine perturbs reward circuitry in MDD, we examined how serial ketamine infusions (SKI) modulate static and dynamic functional connectivity (FC) in Hb and NAc...
Psychological Medicine
October 1, 2022
Ashish K Sahib, Joana R Loureiro, Megha M Vasavada et al.
36 citations
Subanesthetic ketamine infusion therapy can produce fast-acting antidepressant effects in patients with major depression. How single and repeated ketamine treatment modulates the whole-brain functional connectome to affect clinical outcomes remains uncharacterized. Data-driven whole brain functional connectivity (FC) analysis was used to identify the functional connections modified by ketamine...
Psychological Medicine
September 1, 2022
Benjamin Wade, Joana R Loureiro, Ashish K Sahib et al.
18 citations
Ketamine is a rapidly-acting antidepressant treatment with robust response rates. Previous studies have reported that serial ketamine therapy modulates resting state functional connectivity in several large-scale networks, though it remains unknown whether variations in brain structure, function, and connectivity impact subsequent treatment success. We used a data-driven approach to determine...
Translational Psychiatry
July 30, 2020
Ashish K Sahib, Joana Ra Loureiro, Megha M Vasavada et al.
37 citations
Subanesthetic ketamine is found to induce fast-acting and pronounced antidepressant effects, even in treatment resistant depression (TRD). However, it remains unclear how ketamine modulates neural function at the brain systems-level to regulate emotion and behavior. Here, we examined treatment-related changes in the inhibitory control network after single and repeated ketamine therapy in TRD....
Human Brain Mapping
May 1, 2020
Joana R Loureiro, Amber M Leaver, Megha M Vasavada et al.
65 citations
Electroconvulsive therapy (ECT) and ketamine treatment both induce rapidly acting antidepressant effects in patients with major depressive disorder unresponsive to standard treatments, yet their specific impact on emotion processing is unknown. Here, we examined the neural underpinnings of emotion processing within and across patients (N = 44) receiving either ECT (N = 17, mean age: 36.8, 11.0...
Journal of Affective Disorders
January 15, 2016
Megha M Vasavada, Amber M Leaver, Randall Espinoza et al.
58 citations
Ketamine elicits an acute antidepressant effect in patients with major depressive disorder (MDD). Here, we used diffusion imaging to explore whether regional differences in white matter microstructure prior to treatment may predict clinical response 24h following ketamine infusion in 10 MDD patients. FSL's Tract-Based Spatial Statistics (TBSS) established voxel-level differences in fractional...