ArticleThe international journal of neuropsychopharmacology2018
Ketamine Effects on EEG during Therapy of Treatment-Resistant Generalized Anxiety and Social Anxiety.
Article in The international journal of neuropsychopharmacology, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
18 citing papers in PubMed, 1 synthesis or guideline pooled it, 57 citations in OpenAlex.
- Ketamine treatment for refractory anxiety: A systematic review.British journal of clinical pharmacology · 2022Pooled it
- A randomized, placebo-controlled, cross-over trial of ketamine in Rett syndrome.Journal of neurodevelopmental disorders · 2025Trial
- Ketamine for treatment-resistant major depressive disorder: Double-blind active-controlled crossover study.Journal of psychopharmacology (Oxford, England) · 2024Trial
- Ketamine effects on EEG and their links to therapy differ across treatment-resistant major depression, post-traumatic stress disorder, and obsessive-compulsive disorder.The international journal of neuropsychopharmacology · 2026Article
- Hope for Neurotic Disorders: A Summary of New Zealand Research on the Development of Biomarkers and Novel Treatments.Journal of the Royal Society of New Zealand · 2026Article
- Depression, post-traumatic stress disorder, suicidal ideation and ketamine: a case report.Journal of medical case reports · 2024Article
- Decreasing brain activity caused by acute administration of ketamine and alcohol - A randomized, controlled, observer-blinded experimental study.Frontiers in pharmacology · 2024Article
- A Comparison of the Anti-Anxiety Effects of Oral Ketamine and Fluvoxamine in Children with Separation Anxiety Disorder Manifesting as School Refusal.Advanced biomedical research · 2023Article
- Ketamine for treatment of mood disorders and suicidality: A narrative review of recent progress.Annals of clinical psychiatry : official journal of the American Academy of Clinical Psychiatrists · 2022Review
- Associations between Heart Rate Variability and Brain Activity during a Working Memory Task: A Preliminary Electroencephalogram Study on Depression and Anxiety Disorder.Brain sciences · 2022Article
- Predicting Prognostic Effects of Acupuncture for Depression Using the Electroencephalogram.Evidence-based complementary and alternative medicine : eCAM · 2022Article
- Right Frontal Theta: Is It a Response Biomarker for Ketamine's Therapeutic Action in Anxiety Disorders?Frontiers in neuroscience · 2022Article
- Ketamine for the treatment of mental health and substance use disorders: comprehensive systematic review.BJPsych open · 2021Review
- Right frontal anxiolytic-sensitive EEG 'theta' rhythm in the stop-signal task is a theory-based anxiety disorder biomarker.Scientific reports · 2021Article
- Ketamine and neuroticism: a double-hit hypothesis of internalizing disorders.Personality neuroscience · 2020Article
- Ketamine Blocks Morphine-Induced Conditioned Place Preference and Anxiety-Like Behaviors in Mice.Frontiers in behavioral neuroscience · 2020Article
- Higuchi's fractal dimension, but not frontal or posterior alpha asymmetry, predicts PID-5 anxiousness more than depressivity.Scientific reports · 2019Article
- Validating a model of benzodiazepine refractory nerve agent-induced status epilepticus by evaluating the anticonvulsant and neuroprotective effects of scopolamine, memantine, and phenobarbital.Journal of pharmacological and toxicological methodsArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundKetamine is swiftly effective in a range of neurotic disorders that are resistant to conventional antidepressant and anxiolytic drugs. The neural basis for its therapeutic action is unknown. Here we report the effects of ketamine on the EEG of patients with treatment-resistant generalized anxiety and social anxiety disorders.
methodsTwelve patients with refractory DSM-IV generalized anxiety disorder and/or social anxiety disorder provided EEG during 10 minutes of relaxation before and 2 hours after receiving double-blind drug administration. Three ascending ketamine dose levels (0.25, 0.5, and 1 mg/kg) and midazolam (0.01 mg/kg) were given at 1-week intervals to each patient, with the midazolam counterbalanced in dosing position across patients. Anxiety was assessed pre- and postdose with the Fear Questionnaire and HAM-A.
resultsKetamine dose-dependently improved Fear Questionnaire but not HAM-A scores, decreased EEG power most at low (delta) frequency, and increased it most at high (gamma) frequency. Only the decrease in medium-low (theta) frequency at right frontal sites predicted the effect of ketamine on the Fear Questionnaire. Ketamine produced no improvement in Higuchi's fractal dimension at any dose or systematic changes in frontal alpha asymmetry.
conclusionsKetamine may achieve its effects on treatment-resistant generalized anxiety disorder and social anxiety disorder through related mechanisms to the common reduction by conventional anxiolytic drugs in right frontal theta. However, in the current study midazolam did not have such an effect, and it remains to be determined whether, unlike conventional anxiolytics, ketamine changes right frontal theta when it is effective in treatment-resistant depression.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.