You do not currently have permission to view the full text for this document. Please sign in to an account with an active subscription or contact support.
, , , , , & (2001), Functional neuroanatomical correlates of hysterical sensorimotor loss. Brain, 124: 1077-1090. There have been several recent attempts to identify the neurobiological correlates of hysteria, typically focussing on the “prototypical” case of unilateral paralysis. However, in the context of this growing literature, the Vuilleumier et al. investigation is unique in several ways—and offers some remarkably reliable findings on the neurobiology of the disorder. Firstly, the study represents the largest series of patients with conversion disorder ever investigated in a controlled neurophysiological setting. Secondly, it introduces the method of passively vibrating the affected (and the unaffected) limb. This approach is known to activate a range of sensory and motor areas, but avoids the many ambiguities (and possible variations in effort, strategy etc.) that occur when a hysteric is invited to move a limb which they know they cannot move. Finally, it introduces a before-and-after procedure, whereby patients were followed up and re-scanned when their paralysis had improved (complete recovery, during the 2-4 month recovery period, occurred in four of the seven patients). This allows the patient to act as their own control—counteracting a range of potential objections, for example relating to the premorbid personality of hysterics, or co-morbidity in a smallish sample. The findings were remarkably consistent across all cases. All patients showed hypoactivation in a small number of sites in the contralateral basal ganglia, and especially in the contralateral thalamus. Thus, there was less brain activity in just one class of motor structures, restricted to the side which controlled the paralysed limb. It is also notable that, in those who recovered, these areas of under-activation were no longer present. Indeed, the level of underactivation in these regions during the firs