It is believed that many people are troubled by the suspicion of hazy state of consciousness and do not know what tests should be done. The hazy state of consciousness is clinically characterized by a narrowing or narrowing of the range of consciousness, accompanied by a decrease in the level of clarity of consciousness. Conscious activity is concentrated within a narrow and isolated range, and the patient is only able to perceive this part of the experience. Functional brain imaging Functional brain imaging is a class of noninvasive neurological activity measurement-imaging techniques. Brain function research focuses on exploring the neural basis of cognition and emotion, and functional brain imaging is very important. Brain nerve examination There are 12 pairs of brain nerves, which are generally named sequentially using Roman numerals. The first and second pairs (olfactory and optic) of brain nerves are bundles of nerve fibers of their secondary and tertiary neurons in the intracranial part, while the remaining 10 pairs of brain nerves are connected to the brainstem, which contains their nuclei, with the motor nuclei located mostly near the median line and the sensory nuclei on their lateral side. A portion of the Ⅺ brain nerve pairs (paranerves) emanates from the anterior horn of the upper segments of the cervical spinal cord. The cerebral nerves have sensory and motor fibers and mainly innervate the head and face. Cerebral nerve examination is extremely useful for localizing and diagnosing cranial damage. Brain evoked potentials Brain function is examined by brain evoked potentials.