Treating nightmares in posttraumatic stress disorder with dronabinol: study protocol of a multicenter randomized controlled study (THC PTSD-trial).

BACKGROUND: Distressing nightmares are a core symptom of posttraumatic stress disorder (PTSD) and contribute to psychiatric comorbidity, impaired physical health and decreased social functioning. No specific pharmacological treatment for PTSD-related nightmares is yet approved. Preliminary clinical data indicate that cannabinoid agonists can improve nightmares and overall PTSD symptoms in patients with PTSD. The primary objective of the study is to examine the efficacy of oral dronabinol (BX-1) versus placebo in reducing nightmares in patients with PTSD. The secondary objectives of the study are to examine the efficacy of oral BX-1 in reducing other PTSD symptoms. METHODS: The study is designed as a multi-centric, double-blind, randomized (1:1), placebo-controlled, parallel group interventional trial. Eligible patients will be randomized to BX-1 or placebo, receiving a once-daily oral dose before bedtime for 10 weeks. Primary efficacy endpoint is the Clinician-Administered PTSD Scale (CAPS-IV) B2 score for the last week, measuring frequency and intensity of nightmares. Secondary efficacy endpoints are other disorder-specific symptoms in patients with PTSD. Further, tolerability and safety of dronabinol will be assessed. DISCUSSION: This randomized controlled trial will provide evidence whether treating patients with PTSD and nightmares with dronabinol is safe and efficacious. TRIAL REGISTRATION: NCT04448808, EudraCT 2019-002211-25.

Monitoring and control of amygdala neurofeedback involves distributed information processing in the human brain.

Brain-computer interfaces provide conscious access to neural activity by means of brain-derived feedback ("neurofeedback"). An individual's abilities to monitor and control feedback are two necessary processes for effective neurofeedback therapy, yet their underlying functional neuroanatomy is still being debated. In this study, healthy subjects received visual feedback from their amygdala response to negative pictures. Activation and functional connectivity were analyzed to disentangle the role of brain regions in different processes. Feedback monitoring was mapped to the thalamus, ventromedial prefrontal cortex (vmPFC), ventral striatum (VS), and rostral PFC. The VS responded to feedback corresponding to instructions while rPFC activity differentiated between conditions and predicted amygdala regulation. Control involved the lateral PFC, anterior cingulate, and insula. Monitoring and control activity overlapped in the VS and thalamus. Extending current neural models of neurofeedback, this study introduces monitoring and control of feedback as anatomically dissociated processes, and suggests their important role in voluntary neuromodulation.