Neuroimaging correlates and predictors of response to repeated-dose intravenous ketamine in PTSD: preliminary evidence
medRxiv Preprint Server April 10, 2021 Agnes Norbury, Sarah B. Rutter, Abigail B. Collins et al. 1 citation preprint
In a small randomized clinical trial, repeated doses of ketamine improved PTSD symptoms more than midazolam. Brain scans showed that symptom improvement was linked to increased communication between the ventromedial prefrontal cortex and amygdala when viewing emotional faces, especially in those who received ketamine. Ketamine-related improvement was also predicted by decreased activity in the dorsal anterior cingulate during emotional conflict and increased resting-state connectivity between the ventromedial prefrontal cortex and anterior insula. Further analysis indicated that ketamine specifically strengthened the prefrontal cortex's ability to inhibit amygdala responses to threatening social cues, suggesting a normalization of brain circuits involved in fear regulation.