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Updated: Aug 6, 2026
12:18
An Instrumented Pull Test to Characterize Postural Responses
Published on: April 6, 2019
Acceleration threshold detection during short anterior and posterior perturbations on a translating platform
S J Richerson1, L W Faulkner, C J Robinson
1Research Service, Overton Brooks VA Medical Center, Shreveport, LA, USA.
Gait & Posture
|December 5, 2003
Summary
Detecting subtle balance shifts relies on acceleration magnitude, not direction or profile. Understanding these limits helps reveal how the body controls balance moment-to-moment.
Area of Science:
- Biomechanics
- Human Motor Control
- Sensory Neuroscience
Background:
- Postural control research typically examines quiet standing or large perturbations.
- A gap exists in understanding responses to smaller, repeatable perturbations.
- This study investigates the perception of subtle, vibration-free platform translations.
Purpose of the Study:
- To determine the perceptual thresholds for detecting very short-duration platform translations.
- To identify factors influencing the detection of these subtle postural perturbations.
- To gain insights into the sensory mechanisms underlying continuous balance control.
Main Methods:
- Utilized a Latin-square design with anterior/posterior translations (4mm or 20mm).
- Varied acceleration profiles (smooth vs. jerk) and directions.
- Employed a psychophysical method to determine peak acceleration detection thresholds.
Main Results:
- Perturbation length significantly correlated with detection thresholds.
- Shorter (4mm) perturbations required higher peak acceleration (14.51 mm/s²) for detection.
- Longer (20mm) perturbations were detected at lower peak acceleration (8.55 mm/s²).
- Detection was independent of acceleration profile (smooth/jerk) or direction.
Conclusions:
- Perceptual detection of short-duration motion underfoot depends primarily on acceleration magnitude.
- Acceleration profile and direction do not significantly influence the detection of these subtle perturbations.
- Findings inform our understanding of the sensory inputs crucial for real-time postural control.
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