What are the Symptoms of a Brain Injury?

Traumatic brain injuries (TBIs) are typically the result of a blunt blow or jolt to the head or the body. A penetrating injury in which an object passes through the brain tissue, such as a gunshot wound, a shattered piece of skull, or a sharp object, can also result in a TBI. The effects of a mild TBI or a concussion tend to be temporary, while moderate and severe TBIs tend to result in longer lasting or even permanent damages, and in the worst case, can result in death.

What are the symptoms of a TBI? How is a TBI diagnosed? Read on to find the answers to these questions and more.

Brain Damage: Signs, Symptoms, and Diagnosis

Traumatic brain injuries can vary widely, both in the severity of the injury, as well as the effects. The impact can be both physical and psychological in nature, and the side effects can be wide-ranging. Some of the signs or symptoms of a TBI can appear immediately following the accident, and in some cases, it can take days or even weeks for the symptoms to appear.

If you suspect that you are or someone you care for has suffered a traumatic brain injury, no matter the severity, immediate medical care is imperative. Therefore, whenever an incident that involves a blow, bump, or jolt to the head or body, or whenever a penetrating injury to the head occurs, it’s essential to seek prompt medical care. While health care professionals will perform a complete medical assessment of the patient, including brain scans, often, it’s still wise to be aware of the signs and symptoms of a brain injury.

Mild TBI or Concussion

The signs and symptoms of a mild traumatic brain injury or a concussion can vary; however, symptoms of brain injuries of this degree can manifest in one or more of the following symptoms.

Physical Symptoms

  • Persistent headaches
  • Nausea and vomiting
  • Chronic fatigue or drowsiness
  • Speech issues, such as slurred speech or delayed speech
  • Vertigo (dizziness) and/or loss of balance

Cognitive, mental, or behavioral symptoms

  • Loss of consciousness
  • State of confusion, disorientation, or appearance of being “dazed”
  • Problems with memory concentration
  • Memory loss
  • Mood swings or mood changes
  • Feelings of depression and/or anxiety
  • Difficulty falling asleep
  • Sleeping more than usual

Sensory symptoms

  • Blurred vision
  • Ringing in the ears (tinnitus)
  • Strange taste in the mouth, such as a metallic taste
  • Changes in the sense of smell
  • Light or sound sensitivity

Moderate or Severe TBI

Moderate and severe traumatic brain injuries can include a wide range of signs and symptoms, including the signs and symptoms that are associated with mild TBI or concussion, as well as the following symptoms:

Physical symptoms

  • Loss of consciousness for several minutes to several hours
  • Persistent headache or headache that worsens overtime
  • Constant nausea and/or vomiting
  • Convulsions and/or seizures
  • Dilated pupils in one or both of the eyes
  • Inability to waken from sleep
  • Clear fluids draining out of the nose and/or ears
  • Loss of coordination
  • Weakness or numbness in the fingers and/or toes

Cognitive, mental, or behavioral symptoms

  • Profound state of confusion
  • Unusual behavior, such as combativeness or agitation
  • Slurred speech
  • Disruption to consciousness, such as coma

Symptoms in Children and Babies

Young children and babies who are affected by brain injuries may be unable to communicate the effects that they are experiencing, such as sensory issues or headaches. In addition to the above-listed symptoms, children and babies may exhibit one or more of the following when they are suffering from a traumatic brain injury:

  • Unusual irritability
  • Changes in eating or nursing habits; increased or decreased eating or nursing
  • Shortened attention span
  • Persistent crying and inability to be consoled
  • Changes in sleep habits
  • Appears sad or depressed
  • Seizures
  • Unusual sleepiness
  • Loss of interest in favorite activities and/or toys

When to See a Doctor

If you or someone you love has received a blow, jolt, or bump to the head, or has sustained a penetrating injury to the head, seeking emergency medical care as soon as possible is imperative, with or without the above-mentioned symptoms, but especially if one or more of the signs listed above are displayed. It’s important to note that a “mild” brain injury is still considered a serious injury, so even if you or a loved one is exhibiting symptoms that are associated with a “mild” TBI, seeking prompt medical attention is imperative.

Diagnosing Damages Following a Brain Injury

Healthcare providers will perform a thorough assessment of a patient who is suspected to have sustained a TBI. In addition to performing a general health intake and asking key questions related to the injury, a medical professional will also utilize various types of tests and measures in order to diagnose a brain injury. Typically, several measures and tests will be used in concert to not only diagnose the injury and the severity of the effects, but to devise the most effective treatment plan.

In addition to asking patients a series of quick questions and having them perform numerous tasks (known as “neuro-checks”), healthcare providers will also use some of the following tests and measures to diagnose a TBI.

CT Scans

Computerized tomography (CT and also known as a “CAT” scan) takes X-rays of a patient’s head from several angles, creating a complete picture of the brain. A CT scan can quickly show whether or not the brain is bleeding, if it is bruised, or if there is any other damage to the brain.

It should be noted that while CT scans can be a useful tool when diagnosing a brain injury, this type of imaging alone cannot diagnose a TBI. As such, CT scans should be used in combination with other tests and assessments.


Magnetic resonance imaging (MRI) is one of the most common types of imaging tests used to diagnose a traumatic brain injury. An MRI involves the use of magnets, combined with radio waves, to generate images that are more detailed than those that a CT scan can produce. Typically, MRIs are not used in the initial brain injury assessment, due to the length of time it takes to complete; however, it is often used in follow-up exams.

It should be noted that while MRIs can be a highly effective tool for diagnosing traumatic brain injury, injuries may not always appear on an MRI. This is particularly true in cases of delayed manifestation of symptoms. It is for this reason that MRI alone should not be used to diagnose a TBI; rather, this type of imaging can be helpful when used in combination with other tests and measures.