Handling objects in old age: forces and moments acting on the object
Pranav J Parikh1, Kelly J Cole
1Motor Control Laboratories, Department of Health and Human Physiology, University of Iowa, IA, USA. pranav-parikh@uiowa.edu
Journal of Applied Physiology (Bethesda, Md. : 1985)
|January 14, 2012
Summary
Older adults exhibit reduced control over forces and moments during object manipulation tasks compared to younger adults. Practice improves some aspects, but deficits in manual dexterity persist with aging.
Area of Science:
- Neuroscience
- Gerontology
- Biomechanics
Background:
- Manual dexterity and force control decline with aging.
- Understanding age-related changes in motor control is crucial for interventions.
Purpose of the Study:
- To compare force control and object manipulation between older (OA) and younger (YA) adults.
- To investigate the effects of practice on motor performance in OA.
Main Methods:
- Measured external moments and digit-tip force directions during grasp-lift and key-slot tasks.
- Compared performance metrics between OA and YA groups.
Main Results:
- OA showed greater grip force, altered force vector orientations, and larger external moments than YA.
- OA demonstrated greater variability in force direction and slower performance in the key-slot task.
- Practice led to improved digit alignment, reduced grip force, and minimized moments in OA.
Conclusions:
- Aging is associated with diminished capacity to control forces and moments in precision grasp and manipulation.
- These deficits may underlie age-related slowing and reduced manual dexterity.
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