Open AccessAging differentially affects online control and offline control in finger force production
Author(s) -
Yang Sun Park,
Kyung Koh,
Hyun Woo Kwon,
Okjin Lee,
Jae Kun Shim
Publication year - 2018
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0198084
Subject(s) - control (management) , motor control , task (project management) , computer science , neuroscience , physical medicine and rehabilitation , psychology , artificial intelligence , medicine , engineering , systems engineering
Human central nervous system (CNS) undergoes neurological changes during the aging process, leading to declines in hand and finger functions. Previous studies have shown that the CNS can independently process multi-finger force control and moment of force control. However, if both force and moment control are simultaneously imposed by motor task constraints, the CNS needs to resolve competing interests of generating negative and positive covariances between fingers, respectively, which causes “ conflict of interest or COI” . Here, we investigated how aging affects the CNS’s abilities to solve COI through a new experimental paradigm. Both elderly and young subjects performed a constant force production task using index and middle fingers under two conditions, multi-finger pressing with no COI and with COI . We found that the elderly increased variance of a virtual finger (VF: an imagined finger producing the same mechanical effect as both fingers together) in time-to-time basis (i.e. online control), while increasing covariance between individual fingers (IF) forces in trial-to-trial basis (i.e. offline control) with COI than no COI . Aging affects the CNS’s abilities to solve COI by deteriorating VF actions in online control and IF actions in offline control.