4 Types of Brain Injuries and 3 Levels of Severity

A traumatic brain injury (TBI) can happen in almost any accident that involves head trauma. For example, whiplash during a car accident could tear neurons in the brain. A slip and fall accident could rupture blood vessels feeding the brain. A workplace accident could propel an object through your skull and into your brain.

These brain injuries could leave you with minor symptoms that disappear after a few months. But in some cases, they could cause physical, cognitive, and behavioral issues for the rest of your life.

Here are four types of brain injuries and three levels of severity used to describe them.

How Brain Injuries Happen

The brain produces electrical signals to control the body through the nervous system. Brain injuries happen when trauma or disease damages one’s brain cells. This damage disrupts the signals and can even cause the brain cells to die.

There are four types of TBIs, which include:

Blunt Trauma

Blunt trauma occurs when something strikes the brain without penetrating the skull. Blunt trauma can happen when your head hits an object or vice versa. For example, your head could hit the airbag during a car accident.

Cerebrospinal fluid (CSF) surrounds your brain and provides a cushion between your brain and skull. Blunt trauma causes the brain to shift in the CSF, leading to a TBI. 

The most common examples of blunt force TBI include:


In a concussion, the brain moves in the CSF. The pressure of the movement can create widespread but mild brain damage. Small blood vessels may burst, and the brain may swell.

Although concussions can produce life-changing effects, they rarely cause death.


A powerful blunt force can cause the brain to strike the inside of the skull. This results in bleeding, bruising, and swelling.

Bleeding and swelling around the contusion can limit the blood supply to the injured area of the brain. As a result, brain cells can die, leaving you with permanent brain damage.

Blast Injuries

A blunt force does not need to come from a physical object. Explosions can create a blast wave that pressurizes the CSF and squeezes the brain.

Doctors find most TBIs from explosions in members of the armed forces. But they can also result from workplace accidents involving workers in mining, demolition, and other occupations that are exposed to blasting.

Penetrating Trauma

Penetrating trauma happens when an object physically enters the brain. This type of trauma can tear cells and sever the electrical connections in the brain. It can also produce bleeding, bruising, and swelling near the torn area.

Penetrating trauma can happen when a foreign object penetrates the skull. Penetrating trauma can also occur when a blunt force fractures the skull and pushes skull fragments into the brain.

Anoxic Injury

Anoxic injuries occur when trauma deprives the brain of oxygen. These injuries can happen when you cannot breathe. Thus, a drowning accident at a swimming pool can cause a TBI.

Anoxic injuries can also occur from a loss of blood supply to the brain. Bleeding can deprive brain cells of the oxygen they need to live. Swelling can squeeze blood vessels, cutting brain cells off from oxygenated blood.

Diffuse Axonal Injury (DAI)

A DAI happens when violent motion causes nerve cells that are known as axons to tear apart. The whipping motion of your head and neck from a rear-end or front-end collision can cause a DAI. 

Similarly, a DAI can occur from the snapping of your head and neck when you impact the ground after a fall.

Severity of Brain Injuries

TBIs fall into three levels of severity:  Mild, moderate, or severe. The severity of a TBI is determined based on several measurements. But some of these require subjective interpretations. As a result, one doctor’s “mild” might translate into a “moderate” or “severe” diagnosis for another doctor.

Some of the factors involved in rating a TBI include:

The Glasgow Coma Scale

You might have seen this scale in action if you watch sports. EMTs and doctors use this scale to quickly rate a TBI. 

This scale uses three observations to rate a TBI:

  • Eye response
  • Verbal response
  • Motor response

Any loss of consciousness, even momentary, results in a rating of “severe.” Patients that open their eyes spontaneously, answer questions coherently, and move upon request have a mild TBI. 

Patients who require a stimulus to open their eyes, provide confused verbal responses, and move only in response to pain have a moderate or severe TBI.

Brain Images

A CT scan or MRI can reveal the extent of any brain damage. A mild TBI might reveal minor swelling and bleeding. A moderate or severe TBI will exhibit severe hemorrhaging, bruising, swelling, and tissue death.

Intracranial Pressure

In some cases, doctors may insert a pressure probe into the space between the brain and the skull. The pressure measured by the probe will show the amount of swelling. A mild TBI will produce little or no swelling, while a moderate or severe TBI will produce severe swelling.

Effects of Brain Injuries

From your heart rate to your thoughts and emotions, the brain controls everything in your body. It also collects signals from your sensory organs, stores memories, and produces reactions to stimuli.

A TBI can produce a range of symptoms, depending on its severity. 

A mild TBI could result in:

  • Headache
  • Sensitivity to light or sound
  • Tinnitus
  • Blurry vision
  • Dizziness
  • Foggy thoughts
  • Memory loss
  • Irritability
  • Sleep problems

In a mild TBI, these symptoms may last a few weeks to a few months.

A moderate or severe TBI can produce the same symptoms as a mild TBI but with the added symptoms of:

  • Muscle weakness
  • Trouble with balance and coordination
  • Difficulty communicating and concentrating
  • Problems with learning or remembering new information
  • Changes in personality
  • Impulsive behavior

In a moderate to severe TBI, these symptoms can persist for years.

Recovering Compensation for Brain Injuries

A TBI can result in significant difficulties when it comes to getting or keeping a job. It may require months or years of medical treatment, as well as extensive physical or mental therapy.

As a result, you may require compensation to help you deal with your injury. If your TBI resulted from the negligent or intentional acts of a person or business, an injury lawyer can help you seek damages that cover your medical bills, lost income, and pain and suffering.

Contact Our Personal Injury Law Firm For Help Today

For more information, please contact Bradley Law Personal Injury Lawyers at your nearest location to schedule a free case evaluation today.

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