Abstract:
Background: The ability to perceive two tactile stimuli as asynchronous can be measured using the somatosensory temporal discrimination threshold (STDT). In healthy humans, the execution of a voluntary movement determines an increase in STDT values, while the integration of STDT and movement execution is abnormal in patients with basal ganglia disorders. Sensorimotor integration can be modulated using focal muscle vibration (fMV), a neurophysiological approach that selectively activates proprioceptive afferents from the vibrated muscle. Method: In this study, we investigated whether fMV was able to modulate STDT or STDT-movement integration in healthy subjects by measuring them before, during and after fMV applied over the first dorsalis interosseous, abductor pollicis brevis and flexor radialis carpi muscles. Results: The results showed that fMV modulated STDT-movement integration only when applied over the first dorsalis interosseous, namely, the muscle performing the motor task involved in STDT-movement integration. These changes occurred during and up to 10 min after fMV. Differently, fMV did not influence STDT at rest. We suggest that that fMV interferes with the STDT-movement task processing, possibly disrupting the physiological processing of sensory information. Conclusions: This study showed that FMV is able to modulate STDT-movement integration when applied over the muscle involved in the motor task. This result provides further information on the mechanisms underlying fMV, and has potential future implications in basal ganglia disorders characterized by altered sensorimotor integration.
摘要:
背景:可以使用体感时间辨别阈值(STDT)来测量将两个触觉刺激感知为异步的能力。在健康的人类中,自愿运动的执行决定了STDT值的增加,而基底神经节疾病患者的STDT和运动执行的整合异常。可以使用局灶性肌肉振动(fMV)来调节感觉运动整合,一种神经生理学方法,选择性地激活振动肌肉的本体感觉传入。方法:在这项研究中,我们调查了fMV是否能够调节健康受试者的STDT或STDT运动整合,在fMV应用于第一个骨间背侧期间和之后,短截骨外展肌和径向屈肌。结果:结果表明,fMV仅在应用于第一骨间背侧时调节STDT运动整合,即,执行STDT运动整合所涉及的运动任务的肌肉。这些变化发生在fMV期间和最多10分钟后。不同的是,静息时fMV不影响STDT。我们建议fMV干扰STDT移动任务处理,可能会破坏感官信息的生理处理。结论:这项研究表明,当将FMV应用于运动任务所涉及的肌肉上时,FMV能够调节STDT运动整合。此结果提供了有关fMV潜在机制的进一步信息,并在以感觉运动整合改变为特征的基底神经节疾病中具有潜在的未来意义。