Oishi Kazuo, Maeshima Takashi
Health and Sport Sciences Institute, Senshu University, 2-1-1, Higashimita, Tama, Kawasaki, Japan.
J Clin Neurophysiol. 2004 May-Jun;21(3):170-9. doi: 10.1097/00004691-200405000-00005.
Motor imagery (MI), a mental simulation of voluntary motor actions, has been used as a training method for athletes for many years. It is possible that MI techniques might similarly be useful as part of rehabilitative strategies to help people regain skills lost as a consequence of diseases or stroke. Mental activity and stress induce several different autonomic responses as part of the behavioral response to movement (e.g., motor anticipation) and as part of the central planning and preprogramming of movement. However, the interrelationships between MI, the autonomic responses, and the motor system have not yet been worked out. The authors compare a number of autonomic responses (respiration, heart rate, electro skin resistance) and motoneuron excitability (soleus H-reflex) in elite and nonelite speed skaters during MI. In contrast to the nonelite athletes, MI of elite speed skaters is characterized by larger changes in heart rate and respiration, a greater reliance on an internal perspective for MI, a more vivid MI, a more accurate correspondence between the MI and actual race times, and decreased motoneuron excitability. Two observations suggest that the changes in the autonomic responses and motoneuron excitability for the elite speed skaters are related to the effects of central motor programming: (1) there was no correlation between the autonomic responses for MI and those recorded during mental arithmetic; and (2) mental arithmetic did not significantly alter motoneuron activity. It is suggested that in elite speed skaters, the descending neural mechanisms that reduce motoneuron excitability are activated even when full, vivid MI is performed internally. These inhibitory responses of the motor system may enhance actual motor performance under conditions of remarkably high mental stress, such as that which occurs in the Olympic games.
运动想象（MI），即对随意运动动作的心理模拟，多年来一直被用作运动员的训练方法。运动想象技术作为康复策略的一部分，可能同样有助于人们重新获得因疾病或中风而丧失的技能。心理活动和压力会引发几种不同的自主反应，这些反应既是对运动的行为反应（如运动预期）的一部分，也是运动的中枢计划和预编程的一部分。然而，运动想象、自主反应和运动系统之间的相互关系尚未明确。作者比较了精英和非精英速滑运动员在运动想象过程中的一些自主反应（呼吸、心率、皮肤电反应）和运动神经元兴奋性（比目鱼肌H反射）。与非精英运动员相比，精英速滑运动员的运动想象具有心率和呼吸变化更大、对运动想象的内部视角依赖更强、运动想象更生动、运动想象与实际比赛时间的对应更准确以及运动神经元兴奋性降低等特点。两项观察结果表明，精英速滑运动员自主反应和运动神经元兴奋性的变化与中枢运动编程的影响有关：（1）运动想象时的自主反应与心算时记录的自主反应之间没有相关性；（2）心算并未显著改变运动神经元活动。研究表明，在精英速滑运动员中，即使在内部进行完整、生动的运动想象时，降低运动神经元兴奋性的下行神经机制也会被激活。在诸如奥运会等精神压力极高的情况下，运动系统的这些抑制性反应可能会提高实际运动表现。
