Traumatic Brain Injury Symptoms (Easy-to-Understand Guide)

The Center for Disease Control says, on average, approximately 1.7 million people sustain a traumatic brain injury each year in America. It’s important to identify traumatic brain injury symptoms as soon as possible to avoid worsening the condition.


Definition of Traumatic Brain Injury:

A traumatic brain injury is caused by a bump, blow or jolt to the head. This trauma or head injury disrupts the brain’s normal ability to function. Not all blows or jolts to the head result in a traumatic brain injury.

The severity of a brain injury can be “mild,” which could be a brief change in mental status. Or a brain injury could be “severe,” which could be an extended period of unconsciousness or amnesia. Most traumatic brain injuries are concussions.

What is a Concussion? Is it a Traumatic Brain Injury?

A concussion is defined by the United States Center for Disease Control. They say a concussion is a type of traumatic brain injury, caused by a bump, blow, or jolt to the head. Concussions can change the way your brain normally functions. They can occur from a motor vehicle accident or a fall. Or they can even be sustained when a force causes the head and brain to move quickly back and forth without the head itself experiencing trauma.

Traumatic brain injuries can cause a wide range of functional short-term or long-term changes. These traumatic brain injury symptoms could be changes that affect thinking, sensation, language, and sometimes emotions.


Traumatic Brain Injury Symptoms can Affect The Following Brain Functions:

  • Thinking: which is described as memory and reasoning. Sometimes it’s short term memory or long term memory. Reasoning can be a lack of judgment.
  • Sensation: which is a change, or a loss of touch, taste, hearing, smell, or vision.
  • Language: which is a change in the ability to understand language; or a loss of expression or difficulty in communicating.
  • Emotions: which can be newly acquired depression, anxiety, aggression, acting out, social inappropriateness, or personality changes.
  • Other Risks: some brain injuries cause epilepsy, increase the risk for Alzheimer’s disease, Parkinson’s disease, or other brain disorders that develop years later.


Multiple Mild Traumatic Brain Injuries Over Time can Cause Cumulative Cognitive Losses

We’ve all heard about professional boxers, hockey players, and football players having long-term brain damage from repeated head trauma. Multiple mild traumatic brain injuries that occur over an extended period of time can cause cumulative neurological and cognitive losses. – Centers for Disease Control and Prevention (CDC). Sports-related recurrent brain injuries—United States. MMWR 1997;46(10):224–227.

Mild traumatic brain injuries are a result of microscopic damage throughout the brain that initiates a cascade of biochemical events that leads to the subsequent formation of Alzheimer’s-like plaques. – World Alzheimer Congress 2000. American Journal of Epidemiology.

Here’s the Bottom Line: Any Concussion is an Injury to the Brain

Any concussion is an injury to the brain. Some brain injuries are very minor. Others are quite severe. We also know that repetitive concussions lead to severe loss of brain function over time.


Leading Causes of Traumatic Brain Injuries:

  • Falls (35.2%)
  • Motor vehicle traffic accidents (17.3%)
  • Struck by/against events (16.5%)
  • Assaults (10%)


Falls are the Leading Cause of Traumatic Brain Injuries

Falls cause 35.2% of aLl traumatic brain injuries. They also cause half (50%) of the brain injuries among children age 0 to 14 years old. Falls cause a whopping 61% of all the brain injuries in adults 65+ years old.


Motor Vehicle Crashes or Auto Accidents are the 2nd Leading Cause of Traumatic Brain Injuries

Car crashes are the second leading cause of brain injuries at 17.3%. Automobile accidents cause the largest percentage of brain-injury-related deaths at 31.8%. – Faul M, Xu L, Wald MM, Coronado VG. Traumatic brain injury in the United States: emergency department visits, hospitalizations, and deaths. Atlanta (GA): Centers for Disease Control and Prevention, National Center for Injury Prevention and Control; 2010


Physical Trauma is Not the Only Cause of Brain Injuries:

Trauma, falls, car accidents, contact sports, and acceleration/deceleration are the most common physical causes of brain injuries.

Chemical Exposure Causes Brain Injuries:

After trauma, the second largest cause of brain injuries is chemical exposures. This includes things like carbon monoxide poisoning and dangerous neurotoxins such as lead, solvents, and insecticides.


Lack of Oxygen Causes Brain Injuries:

Lack of oxygen is the next largest cause of brain injuries. They range from birth injuries, which is commonly known as cerebral palsy. Cerebral palsy, (CP,) is caused by medical mistakes. It is not a disease, virus, or birth defect. Cerebral palsy is usually quite preventable.

Proper monitoring of an infant in the womb can show stress or lack of oxygen. If the doctors act quickly, the child will be fine. But any delay in recognizing the stress of the child will cause permanent brain injury.


Strokes Cause Brain Injuries:

Stroke is next on the list of brain injuries causes. When blood flow is blocked to the brain, causing a lack of oxygen, some brain cells will die. Or an internal brain bleed can quickly damage brain cells.


Open-Head Injuries Affect the Brain:

Open head injuries are next on the list for causes of brain injuries. When the skull is penetrated or fractured from violence, such as a gunshot wound, or fragments from an explosion or a high-speed motor vehicle crash, it will cause serious brain injuries.


Closed-Head Mild Traumatic Brain Injuries:

Closed-head injuries are when the trauma does not fracture the skull, but the brain is damaged by a sudden shaking or movement of the brain within the skull. If a person’s head and brain experience a sudden shake or jolt, they will have, what is commonly called, an “Axonal Shearing Injury.”

Axonal shearing injuries occur when the axons, very small nerves connecting the white and gray brain matter, are stretched and damaged.


Density of Gray Versus White Brain Matter

Your brain is made up of two types of brain cells: gray and white matter. The center of your brain is “white brain matter.” White brain matter is dense and heavy, while the surrounding gray brain matter is much softer and lighter.

White and gray matter are connected by axons, which are billions of microscopic nerve fibers. Axons transfer information from the gray brain matter to the white brain matter, and vice versa.


What are Axons and What do they do?

Axons are the long, slender highways of brain nerve cells.  Axons are key in sending signals within, to and from the brain. They transmit the impulse from one nerve cell to the and next from gray to white brain cells.


How Sudden Acceleration or Deceleration Causes Brain Injuries:

To understand how brain injuries occur from sudden acceleration or deceleration, let’s think about Newton’s laws of physics. One of Newton’s laws says that “objects in motion will stay in motion, and objects at rest will stay at rest until another force acts upon them.” Since our brains are soft and made of two different tissues, white matter and gray matter, when our head is hit, the skull moves as a direct result of the force. But the brain remains still and unmoved until the force causes the brain to move and catch up with the skull.


The Differences in the Mass of Gray and White Matter Causes them to Move at Different Speeds:

More importantly, the gray matter, which is softer and lighter, moves and stretches more than the dense, heavy white brain matter. So, the connections between the gray and white matter tears since the gray moves more than the white. The tearing between the two types of brain cells is called shearing.

The difference in the mass, or weight and density of the gray and white matter, causes shearing of the axonal nerve connections. Remember, axons are the micro, small nerve fibers that connect the two parts of the brain. The axons help the gray and white matter communicate with each other.


Stretching of the Axons Causes them to Deteriorate Until they Can’t Communicate between Gray and White Matter Anymore

When the axons are stretched or sheared, they suffer micro tears. Over time, the tears to the axon cells don’t heal. Rather, they begin to deteriorate and breakdown until the axons are no longer able to communication information between gray and white brain cells connected by that specific axon.

Scientists used to be puzzled by the fact that brains could be injured in places other than the outer edges of the brain close to the skull. But, now we understand that the different densities of the gray and white brain tissue cause them to move more or less than the other. Because of the differences in their inertial characteristics, gray matter moves more than white matter.

Therefore, there can be damage where the gray and white matter connects by one part moving more than the other. This is why we find damaged brain cells in areas where the gray and white meet instead of only the outer edges of the brain.


Mild, Moderate, and Serious Traumatic Brain Injuries

75% of brain injuries are classified as “mild” brain injuries. However, the definition is not very comforting if you are the one with the “mild brain injury.”

Many emergency department doctors call a concussion a “mild” brain injury because concussions are usually not life-threatening. Even though a concussion is not usually a life-ending injury, it can have a life-altering effect.


What to do Immediately After a Traumatic Brain Injury

  1. Get to an Emergency Room immediately. Traumatic brain injury symptoms get worse over the first 24 hours. This is because traumatic brain injury symptoms are often a cascade of events that take some time to manifest.
  2. If a Person Goes to the ER and they are Sent Home, but Seem to be Getting Worse, Return to the Same ER immediately. This allows the same ER assess the changes. Don’t wait for a doctor’s appointment days later.

You may recall when Natasha Richardson, who fell and hit her head while skiing with her family in Canada. She initially said she felt fine and didn’t show any signs of injury. The ski resort followed emergency protocol and escorted Richardson back to her hotel and recommend she see a doctor. But she refused.

Although no one is quite sure whether or not she lost consciousness, an hour later she started feeling poorly and developed a headache. Her condition worsened. Within 48 hours of her fall, she died of an epidural hematoma (internal bleeding.)

She did not realize she was bleeding internally in her skull, which was putting pressure on her brain. The pressure became so great, that it caused her to die. So, even a simple blow to the head without loss of consciousness can lead to death.


Common Traumatic Brain Injury Symptoms & Signs:

  • Head Pain
  • Nausea Near the Time of Trauma
  • Any Loss of Consciousness
  • Amnesia
  • Confusion
  • Lightheadedness or Dizziness
  • Blurred Vision or Tired Eyes
  • Ringing in the Ears
  • Bad Taste in Mouth
  • Fatigue or Lethargy
  • Change in Sleep Patterns
  • Behavioral or Mood Changes
  • Trouble with Memory, Concentration, Attention, or Thinking


Moderate or Severe Traumatic Brain Injury Symptoms:

  • A Headache that gets Worse or Doesn’t Go Away
  • Repeated Vomiting or Nausea
  • Convulsions or Seizures
  • Inability to Awaken from Sleep
  • Dilation of One or Both Pupils of the Eyes
  • Slurred Speech
  • Weakness or Numbness in the Extremities
  • Loss of Coordination
  • Increased Confusion, Restlessness, or Agitation


Traumatic Brain Injury Symptoms in Mental Disturbances:

  • Attention Problems
  • Memory Problems
  • Speed of Information Processing
  • Speech or Language Problems
  • Mental Organization
  • Perception
  • Task Efficiency
  • Executive Functions
  • Word-Finding
  • Concentration


Physical Signs of Traumatic Brain Injury Symptoms:

  • Headache
  • Sleep Disturbance
  • Fatigue
  • Lack of Energy
  • Nausea
  • Dizziness
  • Ringing in the Ears
  • Blurred Vision
  • Photophobia


Behavioral Changes in Traumatic Brain Injury Symptoms:

  • Irritability
  • Angry Outbursts
  • Rapidly Changeable Mood
  • Dis-inhibition
  • Poor Social Judgment
  • Anxiety
  • Depression


Objective Proof of Brain Injuries With Radiological and Electronic Testing:

When the right tests are performed, doctors can see microstructural brain damage. The American College of Radiology suggests that when attempting to diagnose a brain injury, doctors should be aware of the sensitivity of each type of test and use the most appropriate test based on the circumstances of each person. The following types of radiological testing, in order from least sensitive to most sensitive, can reveal brain injuries:


1. Not Very Sensitive for Brain Injury Detection: X-Ray

This is an easy, fast way to look at our bones. X-Ray is the least effective way to show a closed head brain injury. But, X-Ray is the best test if there is a broken bone, obvious skull fracture, or bullet-type wound.

X-Ray clearly shows broken bones, which can be a strong indicator of a brain injury. It is excellent at showing the bone structures. However, X-Ray is terrible at showing the soft tissues in our bodies, especially the soft tissue in our brains.


2. A Little Sensitive for Brain Injury Detection: CT or CAT Scans

The next, more sensitive test is a CT, or CAT, Scan. Which stands for Computed Tomography. A CT scan is done using a rotating X-Ray machine that combines X-Ray images with a computer to create three-dimensional representations of structures in our head.

CT scans are typically used to detect infarction, tumors calcifications, hemorrhages, and bone trauma in the head. CT scans show bones very well and show some soft tissue. But it is not a very sensitive test that reveals brain damage. If the CT scan shows signs of a brain injury, then other, more sensitive tests will show the brain injury more clearly.


3. Moderately Sensitive for Brain Injury Detection: MRI Testing

The next, more sensitive radiological test is the MRI. Which stands for Magnetic Resonance Imaging. This is a more sophisticated test to show brain damage. Unfortunately, MRI cannot pick up mild brain injuries very well. But, it’s excellent at showing moderate damage.

We can see the brain’s anatomy in very good detail. But, in many brain injury cases, the damage is so small that it won’t be seen on an MRI. One great advantage to MRI is there is no radiation. Which means there are no harmful effects to the human body. MRI is an excellent way to see our anatomy, but it isn’t sensitive enough to show mild brain injuries.

If you want to learn more about how MRI works, please read my articles and watch my videos about how they work: How MRI Works Part I and Types of MRI Part 2.

4. Very Sensitive for Brain Injury Detection: DTI or Diffusion Tensor Imaging

This test is done with the MRI machine. It shows the consistency or disruption of the flow of the brain’s white matter tracts. DTI’s measure the restrictions or disruptions of water diffusion in our brains.

Brain axons are situated in parallel bundles and their myelin covering (sheath) causes water to flow next to the axons in uninterrupted, relatively straight, lines. So in a healthy brain, the water patterns are long and curved like spaghetti strands.

But if a person has a brain injury, like a coup contra coup from a whiplash type injury, then the myelin coverings, or axon sheaths, will be broken, torn or disrupted. DTI’s can reveal this because the water tracks will be interrupted by the shearing injury. Instead of long spaghetti-like strands, it will appear like broken, small pieces of spaghetti.

Imaging and interpretation of water diffusion have improved with the development of diffusion tensor imaging. Diffusion tensor imaging allows direct examination of the axon fibers through the flow of water molecules.

Therefore, if there is microstructure tissue damage in the brain, we can see it. Diffusion tensor imaging provides excellent details of the white brain matter tracks and we can tell by any disruption if there is damage or injury to the brain.


5. Extremely Sensitive for Brain injury Detection: Susceptibility Weighted Imaging (SWI)

Susceptibility Weighted Imaging uses the MRI to show differences in brain matter from one small area to the next. By making tissue comparisons in very small areas, slight differences can be easily seen with SWI.

Signals from substances with different susceptibilities than their neighboring tissues (such as venous blood or hemorrhage) will look different than the brain cells next to it. The computer can detect these differences and reveal them to us quite easily.

SWI shows small areas of the brain that have signs of trauma because residue from iron deposits and calcium will be left where the brain injury is.

2 thoughts on “Traumatic Brain Injury Symptoms (Easy-to-Understand Guide)”

  1. I have so many symptoms of brain injury. A few years ago, I slipped & fell & went unconscious. I was dizzy, but when I told the doctor this he ignored me & so did the staff. On May 3 of this year, someone was in my home talking to me. After I sipped the water she handed me I collapsed & went unconscious for 7 to 8 hours. When I woke up, I crawled to the bed. The affects lasted for months & my pupils were dilated. Today I work up exhausted, off balance & light headed & my pupils were slightly dilated. Going near 18 hours later & I don’t feel much better. I dropped bird seed everywhere. I have been to the hospital many times & all they do is do the same test that shows nothing. Refuse to give me a diagnoses. No I was even profiled. Sometimes, I feel like my brain is too big for my head. I told the police & the health care & nothing has been done.

    • Hi Carol,

      I am sorry to hear about your health issues. I might suggest you find a neurologist to evaluate your problems. Unfortunately most hospital Emergency Departments only stabilize people and keep them from getting worse, and they don’t really have the capacity to fully evaluate a condition. The Emergency Room Doctors don’t usually make diagnosis that involve brain injuries, and they don’t offer treatment. This is why I suggest you find a neurologist who can do an in depth examination, history and evaluation of your conditions.


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