Ghosts in the machine: A Case description of visual and haptic hallucinations after right hemisphere stroke

Abstract

Visual and haptic hallucinations are described in a patient with a right hemisphere infarct. The hallucinations, which lasted intermittently for 10 days, occurred in clear consciousness and in the context of left hemiplegia, sensory loss, hemianopia, and visual neglect. These transient visual hallucinations, characteristic of Charles Bonnet Syndrome, featured children, animals, relatives, dripping water, and traffic, and coexisted with otherwise veridical percepts. Unusual features included the patient's claim to have touched some of the hallucinated objects and the persistent delusion, precipitated by the form of certain hallucinations, that the ward on which she was staying was located one floor above its true position. Specific attention is drawn to the problem of assessing the degree to which the patient showed insight into the hallucinatory nature of some of her percepts. We provide a modular account of the causes of the hallucinations and a central account of how they were interpreted by the patient.