In the upright stance, posture is better controlled to perform precise visual tasks than laser pointing tasks

Area of Science:

• Human movement science
• Neuroscience
• Vision science

Background:

• Young adults exhibit enhanced postural stability during precise visual or pointing tasks compared to quiet standing.
• The potential for synergistic effects between precise visual and pointing tasks on postural control remains unexplored.

Purpose of the Study:

• To investigate whether combining precise visual and pointing tasks further enhances postural stability in young adults.
• To determine the relative contributions of visual and motor tasks to postural control.

Main Methods:

• Twenty-four healthy young adults (mean age 22 years) performed six tasks.
• Tasks involved combinations of precise visual search, unprecise free-viewing, fixation, and pointing with or without a laser.
• Postural sway and body movements were measured during task performance.

Main Results:

• Postural sway was significantly reduced during precise visual tasks compared to fixation tasks.
• Combining precise visual and pointing tasks did not yield additive stabilizing effects.
• Pointing tasks had minimal influence on body movements; participants increased eye and head rotation while decreasing upper back movement during precise visual tasks.

Conclusions:

• Young adults employ a stabilizing coordination strategy involving eye and head movements to facilitate precise visual exploration.
• Posture stabilization appears to be prioritized for successful execution of precise visual tasks over pointing tasks.