Many of the symptoms which are not related to immune dysfunction are grouped in ways which indicate their origin in the nervous system. Notably there are a host of otherwise inexplicable symptoms which relate to disturbance in the function of several of the cranial nerves. For example the Vestibulocochlear nerves serve the senses of hearing & balance, and ME patients often complain of tinnitus & vertigo. Yet others complain of irritable bowel & gut disorders and others of skipped heartbeats, which seems unconnected until you consider that the Vagus nerves serve and regulate these parts of the body. Baroreceptors responsible for sensing blood pressure also connect the aorta and carotid artery to the Vagus and Glossopharyngeal nerves respectively, (both cranial nerves,) which may explain the documented phenomenon of hypotension (low blood pressure) in some ME patients. Others complain of facial twitches and pains, which are diagnosed as neuralgias related to the Facial and Trigeminal nerves. Others complain of blurry vision which may relate to disturbance of the Optic nerves. Taken separately they seem unrelated until you consider the role of cranial nerves in each type of symptom. Additionally the widespread complaint of muscular spasms and cramping indicates that the effects extend to other types of nerves besides the cranial nerves.