Traumatic Brain Injury

A traumatic brain injury – or TBI – is the disruption of normal brain function caused by an external force, including a jolt or blow to the head. Not all blows or jolts to the head cause a TBI. A TBI may be classified as:

  • Mild (most common, also called a concussion)
  • Moderate
  • Severe
  • Penetrating

Possible Symptoms

  • Headaches
  • Dizziness or balance problems
  • Fatigue
  • Feeling depressed, anxious or irritable
  • Nausea
  • Sensitivity to light and sound
  • Sleep problems
  • Trouble with memory and attention
  • Vision changes
  • Impulsivity

For more information, download the What You Should Know About Concussions and Concussion Signs and Symptoms fact sheets.

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