In his play Othello, Shakespeare refers to jealousy as a green-eyed monster. It is an apt description for such a potentially destructive emotion. In the play, Othello kills his wife Desdemona because he believes she has been unfaithful. Unfounded and extreme jealousy has therefore been called Othello syndrome. Other terms have also been used; pathological jealousy, morbid jealousy, delusional jealousy and conjugal paranoia.
Jealousy is a universal human emotion but like other emotions it can become maladaptive and even dangerous. Acknowledging this, the diagnostic manual of the American Psychiatric Disorders includes diagnostic criteria for a psychiatric disorder called Delusional disorder–jealous type.
Dementia and Othello syndrome
Morbid jealousy has been reported in Alzheimers´s disease as well as in other dementias. One of my patients accused her husband of keeping a lover in a nearby house. She also informed everyone she knew of this, thereby causing terrible distress to the elderly husband. Keep in mind that it may appear quite logical for a patient with Alzheimer´s disease to conclude that the spouse is having an affair. For example, if the patient repeatedly sees his spouse speaking on very friendly terms with someone he does not recognize (perhaps because of prosopagnosia) he might reach the erroneous, albeit logical, conclusion that this is his spouse´s love interest. This may eventually lead to a full-blown delusional jealousy.
Parkinson´s disease and Othello syndrome
Cognitive impairment does not necessarily play a role in Othello syndrome and there have been several reports of it in non-demented patients with Parkinson´s disease. It has also been suggested that the syndrome is more common than generally believed in this patient group. In Parkinson´s disease Othello syndrome appears to be a side effect of the dopamine receptor agonists which are used to treat the disease. The drugs stimulate the dopamine receptors in the brain, thus counteracting the dopamine deficiency in Parkinson´s disease. The drugs are also associated with other behavioural changes such as problems with impulse control (e.g., hyper-sexuality, addiction to pornography, pathological gambling) as well as hallucinations and other delusions than delusions of infidelity. These unfortunate side effects generally diminish or disappear when the drugs are withdrawn.
Othello syndrome: Where in the brain?
It has been suggested that a dysfunctional right frontal lobe might be the anatomical basis of Othello syndrome. A recent case study by Narumoto and colleagues supports this. They report on a 61-year-old non-demented woman. She had a right orbitofrontal tumor removed and developed psychiatric problems in the aftermath, including Othello syndrome. Fifteen years had elapsed between the surgery and the development of Othello syndrome which weakens the authors´ argument somewhat. Yet, in light of previous reports on the relationship between Othello syndrome and right frontal impairment it is a noteworthy case study.
Georgiev, D., Danieli, A., Ocepek, L., Novak, D., Zupančič-Križnar, N., Trošt, M. & Pirtošek, Z. (2010). Othello syndrome in patients with Parkinson’s disease. Psychiatria Danubina, 22(1), 94–98.
Graff-Radford, J., Ahlskog, J. E., Bower, J. H. & Josephs, K. A. (2010). Dopamine agonist and Othello´s syndrome. Parkinsonism and Related Disorders, 16, 680-682.
Narumoto, J., Nakamura, K., Kitabayashi, Y. & Fukui, K. (2006). Othello Syndrome Secondary to Right Orbitofrontal Lobe Excision. Journal of Neuropsychiatry and Clinical Neurosciences 18(4), 560-561.
Illustration credit: Eugène Delacroix: The Death of Desdemona [Public domain], via Wikimedia Commons