Learn about brain injury

Traumatic brain injury usually results from a violent blow or jolt to the head or body. An object that penetrates brain tissue, such as a bullet or shattered piece of skull, also can cause traumatic brain injury.

Mild traumatic brain injury may affect your brain cells temporarily. More-serious traumatic brain injury can result in bruising, torn tissues, bleeding and other physical damage to the brain. These injuries can result in long-term complications or death.

Symptoms

Traumatic brain injury can have wide-ranging physical and psychological effects. Some signs or symptoms may appear immediately after the traumatic event, while others may appear days or weeks later.

Physical symptoms

  • Loss of consciousness for a few seconds to a few minutes
  • No loss of consciousness, but a state of being dazed, confused or disoriented
  • Headache
  • Nausea or vomiting
  • Fatigue or drowsiness
  • Problems with speech
  • Difficulty sleeping
  • Sleeping more than usual
  • Dizziness or loss of balance

Sensory symptoms

  • Sensory problems, such as blurred vision, ringing in the ears, a bad taste in the mouth or changes in the ability to smell
  • Sensitivity to light or sound

Cognitive or mental symptoms

  • Memory or concentration problems
  • Mood changes or mood swings
  • Feeling depressed or anxious

Moderate to severe traumatic brain injuries

Moderate to severe traumatic brain injuries can include any of the signs and symptoms of mild injury, as well as these symptoms that may appear within the first hours to days after a head injury:

Physical symptoms

  • Loss of consciousness from several minutes to hours
  • Persistent headache or headache that worsens
  • Repeated vomiting or nausea
  • Convulsions or seizures
  • Dilation of one or both pupils of the eyes
  • Clear fluids draining from the nose or ears
  • Inability to awaken from sleep
  • Weakness or numbness in fingers and toes
  • Loss of coordination

Cognitive or mental symptoms

  • Profound confusion
  • Agitation, combativeness or other unusual behavior
  • Slurred speech
  • Coma and other disorders of consciousness

Children’s symptoms

Infants and young children with brain injuries might not be able to communicate headaches, sensory problems, confusion and similar symptoms. In a child with traumatic brain injury, you may observe:

  • Change in eating or nursing habits
  • Unusual or easy irritability
  • Persistent crying and inability to be consoled
  • Change in ability to pay attention
  • Change in sleep habits
  • Seizures
  • Sad or depressed mood
  • Drowsiness
  • Loss of interest in favorite toys or activities

When to see a doctor

Always see your doctor if you or your child has received a blow to the head or body that concerns you or causes behavioral changes. Seek emergency medical care if there are any signs or symptoms of traumatic brain injury following a recent blow or other traumatic injury to the head.

The terms “mild,” “moderate” and “severe” are used to describe the effect of the injury on brain function. A mild injury to the brain is still a serious injury that requires prompt attention and an accurate diagnosis.