Also known as unilateral hallucination. Both terms are indebted to the Latin words unus (one) and latus (side). They are used to denote an auditory hallucination perceived on one side of the head. Pathophysiologically, unilateral auditory hallucinations are associated with ipsilateral ear lesions (such as otosclerosis or acoustic neuromata) or contralateral brain lesions (more specifically, lesions affecting the contralateral temporal lobe or hippocampus). In clinical practice, however, it is not always possible to demonstrate the presence of such pathological conditions. Unilateral auditory hallucinations due to an ear condition are also referred to as unilateral otopathic auditory hallucinations. The German psychiatrist Friedrich Jolly (1844-1904) has been credited with being the first to reproduce unilateral auditory hallucinations experimentally by means of electrical stimulation of the acoustic nerve. The term unilateral auditory hallucination is used in opposition to the term *bilateral auditory hallucination.
References
Almeida, O.P., Forstl, H., Howard, R., David, A.S. (1993). Unilateral auditory hallucinations. British Journal of Psychiatry, 162, 262-264.
Blom, J.D., Sommer, I.E.C. (2009). Auditory hallucinations. Cognitive and Behavioral Neurology (in press).
Gordon, A.G. (1987). Etiology of unilateral auditory hallucinations. Acta Psychiatrica Scandi-navica, 75, 664-668.
Jolly, F. (1874). Beiträge zur Theorie der Hallucination. Archiv für Psychiatrie, 4, 495-539.
Michéa, C.-F. (1871). Du délire des sensations. Paris: Labé.
Thirthalli, J., Kar, N., Murali, N. (2005). Unilateral auditory hallucinations in the absence of brain or ear pathology in a 27-year-old female. Schizophrenia Research, 77, 357-359.
Dictionary of Hallucinations. J.D. Blom. 2010.