The American Journal of Drug and Alcohol Abuse
January 1, 2007
F. Gerard Moeller, Joel L. Steinberg, Scott D. Lane et al.
39 citations
MDMA users showed reduced longitudinal diffusivity in the rostral body of the corpus callosum, indicating possible microstructural changes, while no differences were found in other diffusivity measures. MDMA users also reported higher impulsivity on the Barratt Impulsiveness Scale and made more disadvantageous choices on the Iowa Gambling Task. A positive correlation emerged between longitudinal diffusivity in the rostral corpus callosum and advantageous decision-making, suggesting a link between white matter integrity and cognitive performance. Further research is needed to understand the causes of these associations.
Neuropsychopharmacology
April 19, 2023
N. Murphy, Amanda J. F. Tamman, Marijn Lijffijt et al.
18 citations
A single low-dose infusion of ketamine in older military veterans with treatment-resistant depression temporarily increases the brain's neural complexity, measured by electroencephalogram (EEG) markers Lempel-Ziv complexity and multiscale entropy, within 30 minutes after infusion. These effects vary over time, with some complexity measures decreasing later. However, these changes in complexity were not linked to reductions in depressive symptoms after seven days. The findings suggest that ketamine produces broad, time-varying effects on brain dynamics beyond previously studied gamma oscillations, offering a potential non-linear marker of the drug's action.
Translational Psychiatry
July 4, 2026
Krisha Shah, Rubén Herzog, Alan C. Swann et al.
Ketamine rapidly reduces depression in some people with treatment-resistant depression, but the brain mechanisms are not fully understood. This analysis of a randomized, double-blind trial compared ketamine to midazolam in 30 older veterans with treatment-resistant depression. Using EEG data and a measure called O-information, which captures how brain regions interact in groups of three or more, the study found that ketamine caused dynamic changes in these interactions over time. The strongest effects occurred in alpha brain waves one hour after infusion, with changes shifting to theta waves by 24 hours and partially returning in beta and gamma waves by day 7.