Temporal features of human tendon vibration illusions

Abstract

Muscle spindles provide information about the position and movement of our bodies. One method for investigating spindle signals is tendon vibration. Vibration of flexor tendons can produce illusions of extension, and vibration of extensor tendons can produce illusions of flexion. Here we estimate the temporal resolution and persistence of these illusions. In Experiments 1 and 2, sequences of alternating vibration of wrist flexor and extensor tendons produced position illusions that varied with alternation period. When vibrations alternated at 1 Hz or slower, perceived position at the end of the sequence depended on the last vibration. When vibrations alternated every 0.3 s, perceived position was independent of the last vibration. Experiment 2 verified and extended these results using more trials and concurrent electromyographic recording. Although tendon vibrations sometimes induce reflexive muscle activity, we found no evidence that such activity contributed to these effects. Experiment 3 investigated how long position sense is retained when not updated by current information from spindles. Our first experiments suggested that vibrating antagonistic tendons simultaneously could produce conflicting inputs, leaving position sense reliant on memory of position prior to vibration onset. We compared variability in position sense after different durations of such double vibration. After 12 s of double vibration, variability across trials exceeded levels predicted from vibrations of flexor or extensor tendons alone. This suggests that position sense memory had decayed too much to substitute for the current conflicting sensory information. Together, our results provide novel, quantitative insight into the temporal properties of tendon vibration illusions.

Short-Term Adaptation of Joint Position Sense Occurs during and after Sustained Vibration of Antagonistic Muscle Pairs

“…Each trial was approximately 40 s in duration, and vibratory stimulus was sustained throughout the duration of all vibration trials (~10 min). The duration of the vibratory stimulus aligns with previous work indicating that simultaneous agonist-antagonist vibration increases position uncertainty after 20 s of sustained vibratory stimulus (Fuentes et al, 2012). …”

“…Changes in the variability of firing properties of muscle spindles, however, may be dependent on the duration of the proceeding vibration stimuli. Fuentes et al (2012) found that variability in the perceived angular position of the wrist joint increased significantly only after 20 s of simultaneous agonist-antagonist tendon vibration. The VIB phase of the present study consisted of ten trials, with each trial lasting approximately 40 s. This effect, therefore, appears to only emerge after prolonged periods of simultaneous vibration.…”

Dynamic Tuning of Tactile Localization to Body Posture

“…Several studies have shown that limb position sense decays over time, even at intervals as short as a few seconds [22][23][24]. This decay could potentially improve performance in the crossed-hands condition specifically since impaired performance in this condition is due to interference from a proprioceptive signal in an external spatial reference frame.…”

Measuring Metacognition of Direct and Indirect Parameters of Voluntary Movement

“…Patients with selective peripheral deafferentiation or volunteers under local anaesthesia may provide such cases. Alternatively, noise can be introduced to proprioceptive feedback, for example, by applying vibration to the relevant muscles and tendons (Fuentes et al, 2012;Goodwin et al, 1972). Studying the effects of the privileged access to motor commands can provide insights for understanding the link between metacognition of voluntary movements and the sense of agency.…”