Methods of treating traumatic brain injury by vagus nerve stimulation

A method of treating a human or animal subject suffering from a symptom caused by traumatic brain injury or characteristic of traumatic brain injury, comprising:

• (a) applying to the vagus nerve of a human or animal subject suffering from a symptom caused by traumatic brain injury or characteristic of traumatic brain injury a stimulating electrical signal having parameters sufficient to alleviate said symptom;
• (b) monitoring said human or animal subject by clinical outcome, a clinical test, a laboratory test, or combinations thereof to determine if said symptom has been alleviated, or if farther stimulation of said vagus nerve is required,
• wherein said laboratory test is selected from the group consisting of a brain scan, a PET scan, a SPECT scan, monitoring the level of a neurotransmitter in the brain, and monitoring the level of a neurotransmitter in spinal fluid;
• and
• (c) if required, further stimulating said vagus nerve and monitoring said human or animal subject as in preceding steps (a) and (b), respectively, until said symptom has been alleviated.