Conversion disorders comprise neurologically unexplained symptoms with a presumed psychiatric cause, though a neuroscientific basis for this is lacking. The standard psychiatric model of conversion holds that events and processes that might explain the symptoms are, by hypothesis, either repressed or subconscious. This makes assessments based on subjective reports unreliable. We circumvent this by using a standardized method to quantify stressful life events and by assessing objectively the neural correlates of emotion processing.
Single case study of a 37-year-old woman with clinically repressed recall and unexplained right-sided paralysis. We describe the application of the Life Events and Difficulties Schedule (LEDS) to her history, and a novel functional magnetic resonance imaging (fMRI) procedure exploring emotion processing of traumatic and control memories.
While in the scanner, cued recall of the clinically repressed event was associated with regional brain activations characteristic of emotional arousal, including the amygdala and right inferior frontal lobe, when compared with an equally severe event from the patient's past, as rated by the LEDS. Such recall was also associated with decreased motor activity in the area corresponding to the subjectively paralyzed limb.
This case study provides neuroimaging evidence for a connection between traumatic events and ongoing neurological symptoms.
CT = computerized tomography; MRI = magnetic resonance imaging; EEG = Electroencephalogram; ICD = International Classification of Diseases; fMRI = functional magnetic resonance imaging; LEDS = Life Events & Difficulties Schedule; mg = milligrams; BA = Brodmann area; T = Tesla; BOLD = Blood Oxygen Level Dependent; TR = Time to repeat.
From the Department of Psychological Medicine (R.A.A.K., S.C.W.), Section of Cognitive Neuropsychiatry (R.A.A.K., A.S.D.), and Department of Health Services Research (T.K.J.C.), King's College London, Institute of Psychiatry, London, United Kingdom.
Address correspondence and reprint requests to Dr. R.A.A. Kanaan, Institute of Psychiatry, Psychological Medicine, P062, WEC, Denmark Hill, London SE5 9RJ. E-mail: email@example.com
Received for publication May 8, 2006; revision received August 24, 2006.