The organization of upper limb physiological tremor

Abstract

The objectives of this study are (1) to assess the relationship between tremor displacement of different segments of the upper limb, (2) to assess whether an attempt to voluntarily reduce tremor amplitude affects this relationship. Twenty-five young healthy participants were tested. Tremor of the finger, hand, arm and shoulder was assessed using laser displacement sensors while the upper limb was in a postural position. Results show strong correlations (r > 0.90), high coherence (>0.9) and in-phase movement between tremor displacement oscillations of different segments. The majority of finger tremor amplitude can be predicted by angular movement generated at the shoulder joint (r(2) > 0.86). Participants were able to voluntarily reduce tremor amplitude, but no change in the relationship between segments was observed. Tremor of all segments of the upper limb was mechanically driven by the angular movement generated at the shoulder joint. This study provides evidence that there is no compensatory organization of physiological tremor. This lays the groundwork to evaluate whether pathological tremors also lack this organization.

Differences Between Men and Women in Balance and Tremor in Relation to Plantar Fascia Laxity During the Menstrual Cycle

“…Tremor is usually altered by changes in spindle reflex loop times and the viscoelastic properties of tendons and ligaments. 34,35 Tendons form a series of elastic components in muscle, 36 and changes in laxity can alter both the amplitude and frequency of tremor. 35 The data for men were the same as those for women during menstruation.…”

The application of accelerometers to measure movements of upper limbs: Pilot study

“…Several studies have documented that the PT in the upper extremity is largely driven by the limb mechanics enhanced by stretch reflex oscillation, but with minimal central influences (Elble, 2003;Raethjen et al, 2004;Raethjen, Pawlas, Lindemann, Wenzelburger, & Deuschl, 2000). In line with this, Carignan, Daneault, and Duval (2012) have found that tremors of all segments are highly correlated and driven by the angular displacement in the shoulder joint.…”

Methods Evaluating Upper Arm and Forearm Movement During a Quiet Stance

“…Several studies have documented, that the PT in the upper extremity is mostly driven by limb mechanics with minimal central influence [38][39][40]. In line with this finding, Carignan et co-workers discovered that tremors of all segments are driven by the angular displacement in the shoulder joint [41]. Side differences in the tremor intensity are not age, gender or laterality dependent, but are dictated by the segment's weight and dimensions [39].…”