Investigation of the relationship between dominant hand abilities and hemispheric dominance

Handedness and hemispheric dominance are thought to influence manual performance, especially dexterity and grip strength, which underpin daily and occupational function. We investigated the effects of handedness and hemispheric dominance (inferred from a neurobehavioral inventory) on dexterity and grip strength, focusing on whether balanced hemispheric dominance confers advantages in mixed-handed/ambidextrous individuals.

This cross-sectional study included 182 adults (aged 19-50 years) who completed the Edinburgh Handedness Inventory to identify hand dominance and a neurobehavioral inventory to assess hemispheric dominance. Grip strength was measured using Constant 14,192-709E and Saehan Pinch Gauge SH5005, while dexterity was evaluated with the Purdue Pegboard Test. Statistical analyses were performed using SPSS 16, with significance set at P < 0.05.

Right-handed participants exhibited significantly higher dexterity in the right hand (P < 0.001), while left-handed individuals showed greater grip strength in both hands, with marginal significance in the right hand (P = 0.046). Mixed-handed/ambidextrous individuals showed significantly higher assembly dexterity scores (P < 0.001). Interhemispheric balance was marginally associated with improved assembly dexterity (P = 0.05), suggesting its role in enhancing motor coordination.

Hand dominance and hemispheric dominance significantly influence motor performance. Balanced hemispheric function in mixed-handed/ambidextrous individuals enhances complex coordination tasks, highlighting potential benefits for rehabilitation strategies. Future research should explore these relationships using neuroimaging techniques and include a broader demographic range to further investigate underlying neural mechanisms.