Traumatic Brain Injury Symptoms

Depending on the extent of damage to the brain, the symptoms of TBI can be mild to severe. Certain symptoms reflect injury to specific areas of the brain: damage to the frontal lobes will cause loss of higher cognitive functions, such as loss of inhibitions leading to inappropriate social behavior; damage to the cerebellum will cause loss of coordination and balance; damage to the brainstem could affect breathing, heart rate and arousal. Mild symptoms may be subtle and not perceptible at the time of the injury.

Additional symptoms include:

  • No loss of consciousness or duration of loss of consciousness of less than 30 minutes
  • Swelling, intracranial pressure
  • Amnesia for events immediately before and after the injury
  • Headache, lightheadedness
  • Confusion, getting lost
  • Visual disturbances, sensitivity to light, blurred vision, eyes that tire easily
  • Ringing in the ears, sensitivity to sounds
  • Nausea, bad taste in the mouth
  • Fatigue, lethargy, lack of motivation
  • A change in sleep patterns
  • Irritability, mood changes
  • Depression
  • Memory or concentration problems

Moderate or severe TBI symptoms may be the same as those for mild TBI, but the symptoms may be harsher. With a moderate brain injury, the patient loses consciousness up to six hours: with a severe brain injury, loss of consciousness is greater than six hours.

  • Persistent headache
  • Repeated vomiting or nausea
  • Convulsions or seizures
  • An inability to awaken from sleep
  • Dilation of one or both pupils of the eyes
  • Speech problems including slurred speech, difficulty understanding the spoken word and difficulty speaking
  • Reading and writing problems
  • Weakness or numbness in the extremities
  • Loss of stamina and coordination
  • Dizziness
  • Lack of motivation
  • Increased confusion, restlessness, agitation or combativeness