• A blow to the head can cause a condition called traumatic brain injury (TBI). The National Institute of Neurological Disorders and Stroke notes the following symptoms associated with TBI: losing consciousness; feeling confused, lethargic, or tired; developing a headache, lightheadedness, or dizziness; blurry vision; ringing in the ears; experiencing a bad taste in the mouth; and experiencing changes in patterns of sleep, behavior, memory, or concentration.
    National Institute of Neurological Disorders and Stroke, November 2016