Sensory Handedness is not Reflected in Cortical Responses After Basic Nerve Stimulation: A MEG Study

Abstract

Motor dominance is well established, but sensory dominance is much less clear. We therefore studied the cortical evoked magnetic fields using magnetoencephalography (MEG) in a group of 20 healthy right handed subjects in order to examine whether standard electrical stimulation of the median and ulnar nerve demonstrated sensory lateralization. The global field power (GFP) curves, as an indication of cortical activation, did not depict sensory lateralization to the dominant left hemisphere. Comparison of the M20, M30, and M70 peak latencies and GFP values exhibited no statistical differences between the hemispheres, indicating no sensory hemispherical dominance at these latencies for each nerve. Field maps at these latencies presented a first and second polarity reversal for both median and ulnar stimulation. Spatial dipole position parameters did not reveal statistical left-right differences at the M20, M30 and M70 peaks for both nerves. Neither did the dipolar strengths at M20, M30 and M70 show a statistical left-right difference for both nerves. Finally, the Laterality Indices of the M20, M30 and M70 strengths did not indicate complete lateralization to one of the hemispheres. After electrical median and ulnar nerve stimulation no evidence was found for sensory hand dominance in brain responses of either hand, as measured by MEG. The results can provide a new assessment of patients with sensory dysfunctions or perceptual distortion when sensory dominance occurs way beyond the estimated norm.

Magnetoencephalographic study of hand and foot sensorimotor organization in 325 consecutive patients evaluated for tumor or epilepsy surgery

“…Simple motor tasks, as in our study, elicit similar responses in both hands, which were also found in our study as well as in other studies with intracranial lesions ( Cheyne et al, 2006 , Nagarajan et al, 2008 , Willemse et al, 2010 ). With respect to the results of sensory stimulation, sensory dominance has not been established with electrical median nerve or pneumatically driven finger stimulation ( Chen et al, 2012 , Zhu et al, 2007 ).…”

The Influence of Hand Dominance in Wrist Fracture Post-Operative Functional Evaluation

“…Differences in sensation have been described in relation to specific occupational groups and function. 28 -30 A recent study by Buitenhuis et al established the use of different sensation standards for normal children. 31 In another study musicians were found to be more sensitive than non-musicians in their dominant hands.…”