RT Journal Article
SR Electronic
T1 A Tensor Decomposition Uncovers the Effect of Ageing on Muscle and Grip-Load Force Couplings During Grasping
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.02.25.482040
DO 10.1101/2022.02.25.482040
A1 Chang Ye
A1 Seyed Saman Saboksayr
A1 William Shaw
A1 Rachel O. Coats
A1 Sarah L. Astill
A1 Gonzalo Mateos
A1 Ioannis Delis
YR 2022
UL http://biorxiv.org/content/early/2022/03/01/2022.02.25.482040.abstract
AB Do motor patterns of grasp-to-lift movements change as a result of ageing? Previous studies often relied on simple temporal and kinetic variables to unveil differences caused by ageing, yet their neuromuscular origins remain largely unknown. Here we employed a bimanual grasping protocol with younger and older adults and combined measurements of muscle activity with grip and load forces to provide a window into the neuromuscular strategies underlying effective grasping. We introduced a tensor decomposition to identify patterns of muscle activity and grip-load force ratios while also characterising their temporal profiles and relative activation across object weights and participants of different age groups. This approach extracted the motor components underpinning object grasping across participants. We then probed age-induced changes in these components. A classification analysis revealed two motor components that are differentially recruited between the two age groups. Linear regression analyses further showed that advanced age and poorer manual dexterity can be predicted by the coupled activation of forearm and hand muscles which is associated with high levels of grip force. Our findings suggest that ageing may induce stronger muscle couplings in distal aspects of the upper limbs, and a less economic grasping strategy to overcome age-related decline in manual dexterity.Competing Interest StatementThe authors have declared no competing interest.