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The organization of upper limb physiological tremor
Benoit Carignan1, Jean-François Daneault, Christian Duval
1Département de Kinanthropologie, Pavillon des Sciences Biologiques, Université du Québec à Montréal, 141 Avenue du Président-Kennedy, Room: SB4290, Montréal, QC H2X 1Y4, Canada.
European Journal of Applied Physiology
|July 26, 2011
Summary
Physiological tremor in the upper limb is mechanically driven by shoulder movement. Voluntary reduction of tremor amplitude did not alter this relationship between limb segments.
Area of Science:
- Neuroscience
- Biomechanics
- Human Physiology
Background:
- Physiological tremor is an involuntary rhythmic movement.
- Understanding tremor organization across limb segments is crucial for diagnosing neurological disorders.
Purpose of the Study:
- To investigate the relationship between tremor displacement in different upper limb segments.
- To determine if voluntary tremor reduction affects this inter-segmental relationship.
Main Methods:
- Twenty-five healthy participants were recruited.
- Laser displacement sensors measured tremor in the finger, hand, arm, and shoulder.
- Upper limb segments were held in a postural position.
Main Results:
- Strong correlations (r > 0.90) and high coherence (>0.9) were observed between tremor oscillations of different segments.
- Shoulder joint angular movement predicted the majority of finger tremor amplitude (r(2) > 0.86).
- Voluntary tremor reduction did not alter the observed relationships.
Conclusions:
- Upper limb tremor is mechanically driven by shoulder joint movement.
- Physiological tremor lacks compensatory organization between limb segments.
- This finding provides a basis for investigating pathological tremors.
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