Age-related Differences in Sensorimotor Transformations for Visual and/or Somatosensory Targets: Planning or...

Area of Science:

• Neuroscience
• Human Movement Science
• Gerontology

Background:

• Individuals utilize sensory information differently for movement planning and control.
• Younger adults exhibit distinct sensorimotor transformations for visual versus somatosensory targets.
• The impact of aging on sensorimotor transformations across different target modalities remains unclear.

Purpose of the Study:

• To investigate age-related differences in sensorimotor transformations during reaching movements.
• To compare how younger and older adults process visual, somatosensory, and bimodal targets.
• To determine if older adults exhibit altered planning mechanisms for movements to targets of varying sensory inputs.

Main Methods:

• Participants included 12 younger (mean age 22) and 12 older adults (mean age 67).
• Reaching movements to visual, somatosensory, and bimodal targets were performed in a dark room.
• Data were analyzed using a 2 Age-Group by 3-Target Modality ANOVA.

Main Results:

• Endpoint precision was highest for visual or bimodal targets in both age groups.
• Older adults had significantly longer reaction times (RTs) than younger adults, particularly for somatosensory targets (Cohen's d = 0.95).
• Movement execution control appeared comparable between age groups, suggesting planning, not execution, is affected.

Conclusions:

• Older adults demonstrate altered sensorimotor planning mechanisms compared to younger adults.
• Aging may impair the ability to perform sensorimotor transformations for locating somatosensory targets.
• Findings suggest potential applications for designing physical activity and rehabilitation programs for older adults.