An fMRI study of musicians with focal dystonia during tapping tasks

Abstract

Musician's dystonia is a type of task specific dystonia for which the pathophysiology is not clear. In this study, we performed functional magnetic resonance imaging to investigate the motor-related brain activity associated with musician's dystonia. We compared brain activities measured from subjects with focal hand dystonia and normal (control) musicians during right-hand, left-hand, and both-hands tapping tasks. We found activations in the thalamus and the basal ganglia during the tapping tasks in the control group but not in the dystonia group. For both groups, we detected significant activations in the contralateral sensorimotor areas, including the premotor area and cerebellum, during each tapping task. Moreover, direct comparison between the dystonia and control groups showed that the dystonia group had greater activity in the ipsilateral premotor area during the right-hand tapping task and less activity in the left cerebellum during the both-hands tapping task. Thus, the dystonic musicians showed irregular activation patterns in the motor-association system. We suggest that irregular neural activity patterns in dystonic subjects reflect dystonic neural malfunction and consequent compensatory activity to maintain appropriate voluntary movements.

Impairment of a parieto‐premotor network specialized for handwriting in writer's cramp

“…The superior parietal cortex shows a non-specific increase of activation in WC patients. Abnormal activation of the superior parietal cortex was also found in dystonic patients without task-specific symptoms [Delnooz et al, 2013], as well as in task specific dystonia during non symptomatic tasks or at rest [Delnooz et al, 2012; Gallea et al, 2015; Kadota et al, 2010; Moore et al, 2012]. The superior parietal cortex is involved in the central processes for writing [Planton et al, 2013; Sugihara et al, 2006; Sakurai et al, 2007], which is confirmed by the increase of activation in this area for the contrast writing versus zigzagging.…”

Neural network of primary focal dystonia by an anatomic likelihood estimation meta-analysis of gray matter abnormalities

“…Clinical features of "sensory trick" presented in patients with dystonia [42,43], abnormal activities detected in sensorimotor areas by using functional MRI [44][45][46], as well as a disordered cortical representation of digits detected in the somatosensory cortex in patients with focal hand dystonia by using Magnetoencephalography (MEG) technique [47] suggest that dysfunction of sensory-motor circuit integration [6,7] also plays a pivotal role in the pathophysiology of focal dystonia, although dysfunction of basal ganglia motor circuit is considered as the classical circuit in the development of focal dystonia [2,48]. The findings of GM deficits in sensorimotor areas including postcentral area (BA2, 3, 40) and primary motor cortex (PMC, BA4) in the current meta-analysis were in good agreement with the theory of pathophysiology of focal dystonia.…”

Focal dystonia and the Sensory-Motor Integrative Loop for Enacting (SMILE)

“…However, no involvement of cerebellum or basal ganglia was reported. Additional investigations on the potential influence of movement complexity showed premotor hyperactivity and cerebellar hypoactivity associated with unimanual and bimanual finger tapping in FHD patients (Kadota et al, 2010). Hu et al (2006) asked FHD patients to perform progressively more complex kinds of writing while being in the fMRI scanner and, with respect to healthy controls, they found increased activation in motor cortex, basal ganglia and cerebellum associated with complex writing (using the pen) but no differences for simple writing (using the finger).…”