Unexpected awakenings in severe dementia from case reports to laboratory.
Alzheimer's & dementia : the journal of the Alzheimer's Association January 1, 2021 Mehmet Bostanciklioğlu 17 citations
Case reports of unexpected memory retrieval in patients with severe dementia near death challenge the view that dementia is an irreversible consolidation problem, suggesting instead a retrieval problem. The likely mechanism involves fluctuating neuromodulators from the brain stem to the medial prefrontal cortex and hippocampus. Around death, neurotransmitter discharges change dramatically, and relatively resistant neuromodulator circuits can maintain optimal arousal and attention for memory processing, triggering episodes of lucidity. Corticotropin-releasing peptides may further increase mental clarity. No animal or human model exists to test this hypothesis, but similarities with delirium and lucid dreaming could provide windows for future research.