Tactile spatial resolution in unilateral brain lesions and its correlation with digital dexterity

Bleyenheuft, Yannick [UCL] Thonnard, Jean-Louis [UCL]

Objective: To test the tactile spatial resolution in chronic unilateral brain lesions. Additionally, since sensory deficits are thought to have an impact on motor deficits, this study investigated the correlation between tactile spatial resolution and finger dexterity. Design: Descriptive cross-sectional study. Patients: Twenty-two patients with unilateral brain lesions (12 children with congenital hemiplegia and 10 patients after stroke). Methods: Tactile spatial resolution was measured with a grating orientation task, and finger dexterity with the Purdue Pegboard Test. Results: Major tactile spatial resolution deficits were measured on the paretic hand and preserved abilities on the non-paretic hand, both in children with congenital hemiplegia and in patients after stroke. No correlation was found between the deficits of tactile spatial resolution and digital dexterity in the paretic hand (r=0.126; p=0372). Conclusion: The specific location of tactile spatial resolution deficits on the hand contralateral to the lesion was surprising when one considers the left hemispheric dominance of tactile spatial resolution in healthy subjects. The absence of correlation between tactile spatial resolution and dexterity deficits suggest that these abilities are not related, suggesting that they should be considered separately and equally integrated into the rehabilitation of unilateral brain lesions.