The headache after waking up from a nap usually has the following factors: 1, the sleep time during the nap is relatively short, it is difficult for people to enter the deep sleep phase, in the nap phase are shallow sleep phase, shallow sleep phase when the nervous system can not fully do a full relaxation, this time there will be a certain neurogenic headache after waking up. 2, in the nap, if there is cervical spondylosis, peri-shoulder discomfort or there is a Certain neck and shoulder compression, this time will also wake up after the nap, feel a certain neurovascular source of headache. 3, when people take a nap, if they are stimulated by sound, light and electricity during sleep. Because the natural law of the afternoon is that there is sunlight outside, this time if you receive a light stimulation while sleeping, there will also be a transient abnormal neuronal discharge, and headaches will also occur when you wake up.