Descriptive Psychopathology: The Signs and Symptoms of ...

185 Chapter 7: Disturbances of motor functionaffected limbs. 148 For example, when attempting to move, a patient with leftsidedidiopathic paralysis was found to have loss of activation of the rightprimary motor strip and hypermetabolism in the right orbitofrontal and anteriorcingulate cortex. 149 This is not willed inactivity, because voluntary inhibition oflimb movement is associated with increased, not decreased, cortical activity. 150The factitious/malingering model posits that patients with the conversiondiagnoses are feigning illness. In a report of 37 persons identified as having“psychogenic” stance and gait disturbances, video study revealed characteristicsigns of factitious impairment, including momentary fluctuations in the abnormality,excessive slowness or hesitation without any associated neurologic orpsychiatric explanatory findings, Romberg sway amplitudes that were delayedand subsequently improved by distraction, a “walking on ice” gait with theperson taking small steps with fixed ankle joints, and sudden buckling of theknees without falling. 151Among patients admitted over a 27-year period to a rehabilitation department,less than 1% (N¼34) were identified as having “conversion motor paralysis”. 152The investigators identified 4 “malingerers” and the remaining 30 are offered asexamples of possible psychogenic movement disorder. Five illustrative vignettesare presented. Two of these were also clearly malingering or exaggerating theirsymptoms, and a third, a man with a head injury and L1 and L2 vertebralfractures and associated right hemiplegia, stuttering, rage attacks and “confusion”,was said to have an “organic brain syndrome” (possibly a seizure disorder). Thefourth, a woman who fell, sustaining a C8 injury and peripheral nerve injuryfollowed by left-sided weakness, was also said to have “a genuine organic problem”.The fifth patient, a 22-year-old woman who lost consciousness after beinghit by a motor vehicle and had posttraumatic amnesia, developed weakness in alllimbs and clonus temporarily relieved by traction. Her spastic weakness withoutsensory or autonomic deficits resolved after a week of rehabilitation. This lastvignette is the only one presented that can be seriously considered to havesymptoms without an identified adequate neurologic or malingering explanation.Considering the review covered almost three decades of admissions, that less than1% of the admissions were considered psychogenic, and that most of thosepatients had explanatory pathology or were malingering, the independence ofpsychogenic movement disorder is doubtful.The non-independent model of conversion disorder proposes that such conditionsare symptoms that reflect neuropathology or a psychiatric disorder withestablished validity. This view is consistent with the studies cited previously andnumerous case reports. 153 Patient 7.10 describes a man with a movement disorderassociated with melancholia.