Wear cervical pillow can not sleep for the following two reasons: First, most of the cervical pillow for the curved and narrow width can not be completely lying down or side-lying position to fill the cervical spine physiological curvature, and therefore can not make the neck muscles to get sufficient relaxation and rest instead of making the neck muscles continue to be tense in the process of sleep, resulting in stiffness and pain in the neck and even pillow phenomenon when you get up in the morning; Second, the cervical pillow softness and hardness can not provide sufficient support for the neck, or even collapse, resulting in the cervical vertebrae in the process of sleep, too much backward stretching or too much lateral flexion, which affects the spinal arteries supplying blood to the brain over a long time, but also can be the emergence of cerebral atrophy symptoms.