A functional magnetic resonance imaging study on writer's cramp / 中华神经科杂志

ABSTRACT

Objective In this study,functional magnetic resonance imaging(fMRI)is performed to visualize what type of brain activity correlates with writer's cramp.Methods Ten patients with writer's cramp and ten age-and gender-matched control subjects participated in this study.fMRI block design is used.Subjects were scanned while performing three visually instructive tasks with MR Vision 2000(1)suppositional writing;(2)writing with finger;(3)writing with a pencil.Data were analyzed with Analysis of Functional Neuroimaging(AFNI)software for groups of patients versus controls.Results Compared with controls,patients with writer's cramp showed greater activation of contralateral basal ganglion(especially the putamen,864 activated voxels in patients versus 54 in controls),ipsilateral cerebellar hemisphere,and contralateral sensorimotor,supplementary motor,premoter,primary sensory cortex in the task of writing with a pencil.There is no obvious difference in the task of writing compared with finger writing.Furthermore,these differences existed in the subtractive activated maps for “writing with pencil” minus “writing with finger”,while the activation of subcortical area and insula in controls disappeared.Conclusion These results indicate that the dysfunction of basal ganglion and subcortical-cortical loop might play a pathophysiologic role in the writer's cramp.