One year after a fluid-percussion traumatic brain injury, male rats showed persistent sensorimotor, learning, memory, and affective deficits; reduced serotonin 2A receptor binding; and microglial changes in the medial prefrontal cortex, including decreased process branching and enlarged soma size. A single dose of psilocybin (1 mg/kg) improved sensorimotor function, restored serotonin 2A receptor binding, and reduced microglial cell counts. These results suggest psilocybin has therapeutic potential for chronic traumatic brain injury and support further investigation of psychedelic treatments.
A neural marker based on high-beta oscillations measured during a simple audiotactile task can detect consciousness and predict recovery in patients with disorders of consciousness. The marker, derived from the peripersonal space system, was present in healthy participants during wakefulness and dreaming but absent in dreamless sleep. In 72 patients with disorders of consciousness, the marker correlated with behavioral measures of consciousness and predicted recovery at discharge. The marker was also associated with forebrain mesocircuit integrity, suggesting a bedside-compatible tool for detecting covert consciousness and guiding clinical decisions in unresponsive patients.