Systematic review · 2025
Review of brain markers linked to reduced suicidal thoughts, including with IV ketamine
- Original title
- Neurophysiological biomarkers of treatment response in suicidal ideation: a systematic review.
- Authors
- Stapper N, Benster LL, Menon S, et al.
- Journal
- Translational psychiatry, 2025
- Molecules
- Ketamine
- Conditions
- Suicidal ideation, Depression
- Evidence grade
- Low
- Source
- Read the original paper
The question
Can brain-based measures show which treatments reduce suicidal thoughts, and how they work? The review asked what neurophysiological markers track treatment-related changes in suicidal ideation.
What they did
Researchers searched three research databases (Embase, PubMed and PsycInfo) using standard systematic review methods. They looked for clinical trials that measured brain activity alongside changes in suicidal thinking during treatment. Twenty-four articles met the criteria, most published in the past five years.
What they found
The included studies varied widely in methods, so findings did not line up neatly. Across studies, activity in the anterior cingulate cortex (a brain region involved in emotion and conflict monitoring) was linked to reductions in suicidal thinking after intravenous ketamine. That signal was not seen in people given ketamine by mouth, which the authors suggest may relate to reports that the intravenous route works better for suicidal thoughts. For electroconvulsive therapy and magnetic seizure therapy, improvements were instead associated with activity in the prefrontal cortex.
The fine print
The review found substantial differences between studies, limited overlap in results, and problems including non-randomized designs, other treatments given at the same time, incomplete treatment protocols and unvalidated measures of suicidal thinking. No pooled numbers or total participant count are reported in the abstract. Brain markers are indirect measures, not patient outcomes in themselves. This summary is based on the abstract only.
What it means
Evidence so far hints that different brain regions may be involved in how intravenous ketamine and seizure-based therapies affect suicidal thoughts, but the studies are too varied and too weak in design to draw firm conclusions.
Evidence grade: Low. A systematic review without pooled analysis, drawing on 24 studies that the authors describe as methodologically varied and often non-randomized.
This summary is based on the study’s published abstract.