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Previous studies showed cortical dysfunction and impaired sensorimotor integration in primary generalized and focal hand dystonia. We used a whistling task and silent event-related fMRI to investigate functional changes in patients with blepharospasm and patients with a combination of blepharospasm and oromandibular dystonia (Meige's syndrome). Whistling served as a model for a skilful orofacial movement with a high demand on sensorimotor integration. It allowed us to study the oromandibular motor system that is clinically affected in Meige's syndrome but not in isolated blepharospasm. In Meige's syndrome, functional MRI revealed deficient activation of the primary motor and ventral premotor cortex within the mouth representation area during whistling. Compared with healthy controls, both forms of orofacial dystonia had increased activation of bilateral somatosensory areas and the caudal supplementary motor area (SMA) in common. While overactivity of somatosensory areas and caudal SMA in Meige patients was partly reversed by botulinum toxin treatment, impaired motor activation was not. We conclude that impaired motor activation appears to be specific for the clinically affected oromandibular motor system in Meige's syndrome while enhanced somatosensory activation is a common abnormality in both forms of orofacial dystonia independent of the affected motor system. Somatosensory overactivity indicates an altered somatosensory representation in orofacial dystonia while impaired motor activation may be a functional correlate of reduced cortical inhibition during oromandibular motor execution in Meige's syndrome.

ObjectivesRecent repetitive TMS (rTMS) mapping protocols for language mapping revealed deficits of this method, mainly in posterior brain regions. Therefore this study analyzed the impact of different language tasks on the localization of language-positive brain regions and compared their effectiveness, especially with regard to posterior brain regions.MethodsNineteen healthy, right-handed subjects performed object naming, pseudoword reading, verb generation, and action naming during rTMS language mapping of the left hemisphere. Synchronically, 5 Hz/10 pulses were applied with a 0 ms delayResultsThe object naming task evoked the highest error rate (14%), followed by verb generation (13%) and action naming (11%). The latter revealed more errors in posterior than in anterior areas. Pseudoword reading barely generated errors, except for phonological paraphasias.ConclusionsIn general, among the evaluated language tasks, object naming is the most discriminative task to detect language-positive regions via rTMS. However, other tasks might be used for more specific questions.

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