Visual hallucinations on eye closure associated with atropine toxicity. A neurological analysis and comparison with other visual hallucinations.

Visual hallucinations of remarkable intensity began shortly after intravenous atropine and persisted for 11 days. They were present only when the eyes were closed and were associated with heightened dreaming and disturbed sleep. The patient remained lucid and described his experiences to his attendants. Our patient's hallucinations bore some resemblance to hypnagogic hallucinations and this became the basis for the hypothesis that the hallucinations originated in the sleep-dream system of the brain stem. It is speculated that a similar site--a metabolic locus minoris resistentiae may play a part in other types of visual hallucinations and in delirium.