Faculty Collaboration Database

The neural foundations of handedness: insights from a rare case of deafferentation. J Neurophysiol 2020 Jul 01;124(1):259-267

Date

06/25/2020

Pubmed ID

32579409

Pubmed Central ID

PMC7474455

DOI

10.1152/jn.00150.2020

Scopus ID

2-s2.0-85088484765 (requires institutional sign-in at Scopus site)   17 Citations

Abstract

The role of proprioceptive feedback on motor lateralization remains unclear. We asked whether motor lateralization is dependent on proprioceptive feedback by examining a rare case of proprioceptive deafferentation (GL). Motor lateralization is thought to arise from asymmetries in neural organization, particularly at the cortical level. For example, we have previously provided evidence that the left hemisphere mediates optimal motor control that allows execution of smooth and efficient arm trajectories, while the right hemisphere mediates impedance control that can achieve stable and accurate final arm postures. The role of proprioception in both of these processes has previously been demonstrated empirically, bringing into question whether loss of proprioception will disrupt lateralization of motor performance. In this study, we assessed whether the loss of online sensory information produces deficits in integrating specific control contributions from each hemisphere by using a reaching task to examine upper limb kinematics in GL and five age-matched controls. Behavioral findings revealed differential deficits in the control of the left and right hands in GL and performance deficits in each of GL's hands compared with controls. Computational simulations can explain the behavioral results as a disruption in the integration of postural and trajectory control mechanisms when no somatosensory information is available. This rare case of proprioceptive deafferentation provides insights into developing a more accurate understanding of handedness that emphasizes the role of proprioception in both predictive and feedback control mechanisms.NEW & NOTEWORTHY The role of proprioceptive feedback on the lateralization of motor control mechanisms is unclear. We examined upper limb kinematics in a rare case of peripheral deafferentation to determine the role of sensory information in integrating motor control mechanisms from each hemisphere. Our empirical findings and computational simulations showed that the loss of somatosensory information results in an impaired integration of control mechanisms, thus providing support for a complementary dominance hypothesis of handedness.

Author List

Jayasinghe SAL, Sarlegna FR, Scheidt RA, Sainburg RL

Author

Robert Scheidt BS,MS,PhD Associate Professor in the Biomedical Engineering department at Marquette University

MESH terms used to index this publication - Major topics in bold

Aged
Biomechanical Phenomena
Feedback, Physiological
Female
Functional Laterality
Humans
Motor Activity
Neurons, Afferent
Peripheral Nervous System Diseases
Proprioception
Sensation Disorders
Upper Extremity