Carlos Morra and Ernst Franzek: Psychopathological Symptoms
Definition: The absence of visual perception of objects of real existence by subjects with normal visual capacity (Keefover, Ringel and Roy 1988).
Exploration: The presence of negative hallucinations can be established by interviewing the patient.
Keefover RT, Ringel R, Roy EP. Negative hallucinations: an ictal phenomenon of partial complex seizures. J Neurol Neurosurg Psychiatry 1988; 51: 454-5
February 8, 2018