在路边的停车当中,常常会看到一些跑长途的驾驶员伏在方向盘上睡眠。虽然仅睡了十几分钟,醒来后却会觉得头沉或头痛,比没睡前更难受。这是因为,人在睡眠中,交感神经处于抑制状态,副交感神经则处于兴奋状态,这样就会使心脏收缩力减弱,心脏功能仅处于维持周身血液循环的状态,加上这时血管壁松驰,血压也相应降 Among the roadside parking, often see some run long-distance driver volt sleep on the steering wheel. Although only slept for more than a dozen minutes, wake up but will feel head Shen or headache, more uncomfortable than before going to sleep. This is because, in sleep, the sympathetic in the inhibitory state, the parasympathetic in the excited state, so that will make the heart contractility reduced, the heart function is only in the maintenance of the whole body blood circulation, coupled with the relaxation of the vessel wall , Blood pressure also dropped accordingly