Mechanismen nichtorganischer Lähmungen: Bewegungswahrnehmung und Bewegungsausführung unter hypnotisch induzierter Lähmung. Eine fMRT-Studie

The neurobiological correlates of nonorganic movement disorders are largely unresolved. Since conversion disorder and hypnotic states have many features in common, a paradigm established in conversion disorder was used to investigate hypnotic paralysis. While engaging in an active movement imitation and a passive movement observation task, nineteen healthy subjects were investigated by functional magnetic resonance imaging with and without hypnotically induced paralysis of one hand. Cerebral activation changes were explored in a multivariate general linear model, by means of factor analysis and by computing functional connectivities. Movement imitation under hypnotic paralysis resulted in a hypoactivation of the contralateral primary motor cortex and the ipsilateral cerebellum, as well as hyperactivation of the contralateral anterior cingulate cortex (ACC), middle frontal gyrus (MFG) and insula. No such paralysis specific effects were obtained in the observation condition. These data suggest that MFG, ACC and insula are involved in hypnotic paralysis by constant self-monitoring and conflict-detecting processes, a rerepresentation of interoception, a mediation of the feeling of agency, an adjustment of executive processes and possibly a modification of intention.