What Is Traumatic Brain Injury?

A primer on the types of brain injuries, the causes, treatments, and stages of recovery

Request our Free Book on Traumatic Brain Injury

The U.S. Centers for Disease Control and Prevention defines Traumatic Brain Injury (TBI) as a disruption in normal brain function caused by a penetrating head injury or a bump, blow, or jolt to the head.

Since the brain defines who a person is, the consequences of an injury like this can affect all aspects of a patient’s life, right down to their basic personality. Also called an intracranial injury, TBI is different from a broken limb or punctured lung. An injury in these areas limits a patient’s use of a specific body part, but their personality and ability remain unchanged. Most often, these body structures heal and regain their previous function.

But traumatic brain injuries do not heal like other injuries, and recovery is based on mechanisms that are not fully predictable. No two brain injuries are alike, and the consequences of two similar injuries are often very different — with symptoms that can appear right away or arise days or weeks after the injury.

Understanding what a traumatic brain injury is — along with its symptoms, causes, and treatments — can help in early identification and management, leading to better outcomes for all of those affected by this often life-changing diagnosis.

Leading Causes of TBI
TBI Symptoms
Stages of Recovery
Prevention Strategies
Living With TBI
Frequently Asked Questions
Get Legal Help

Key Facts

2.5 Million

approximate number of people who suffer a TBI each year

50,000

result in death

80,000

result in permanent disability

28%

Traumatic brain injuries are caused by accidents and falls

Sources: The Brain Trauma Foundation and U.S. Centers for Disease Control and Prevention

Leading Causes of Traumatic Brain Injury

The leading causes include:

Falls (28%)
Motorcycle and motor vehicle crashes (20%)
Being hit by or colliding with an object (19%)
Assaults (11%)
Other — Spinal cord injuries, sports injuries, birth injuries, cerebral palsy, and medical malpractice/negligence (12%)

Sources: The Brain Trauma Foundation and U.S. Centers for Disease Control and Prevention

What Are the Main Types of Traumatic Brain Injury?

There are a wide range of injuries that fall into the TBI category. They include:

Concussion — A mild TBI that affects brain function
Contusion — Bruising from a blow, impact, or fall
Brain Hemorrhage — Sudden bleeding within the brain tissues or ventricles
Diffuse Axonal Injury — A tearing of the brain’s long connective nerve fibers
Skull Fracture — A break in one of the eight cranial bones
Closed Brain Injury — A “blunt head injury” or nonpenetrating injury to the brain with no break in the skull caused by rapid forward, backward, or shaking movements of the brain
Penetrating Injury — An “open head injury” that occurs when the skull is broken or pierced and brain tissue is damaged. A penetrating TBI can happen if the skull is fractured in a fall or motor vehicle crashed, or when the skull is pierced by a sharp object, like a bullet or shrapnel.

Sources: Johns Hopkins Medicine and Flint Rehab

Who is Prone to Traumatic Brain Injuries?

Traumatic brain injuries can occur at any age, in any setting, and regardless of safety precautions taken. However, those who are exceptionally young or old, those who use drugs and alcohol, and those who engage in high-risk activities and jobs are far more likely to suffer from TBI.

Did You Know?

High-Risk Sports and Recreational Activities Include

Contact and extreme sports (football, rugby, boxing, hockey, skateboarding, skiing, snowboarding, etc.)
Bicycling and motorcycling
Horseback riding

High-Risk Jobs Include

Construction, industrial and manufacturing workers
Military personnel
Athletes
First responders
Transport/delivery workers
Agricultural workers

Motorcycle Accidents and TBI

Protect your rights and recovery. For information on understanding TBI caused by motorcycle accidents, including causes, symptoms, treatments, and legal options for compensation, read our article “Traumatic Brain Injuries From Motorcycle Accidents”.

Learn more

A Look at Traumatic Brain Injury Symptoms: Mild, Moderate, and Severe

Symptoms of TBI are classified as mild, moderate, or severe by medical practitioners. However, these labels can be misleading and overly simplistic because they fail to capture the complex nuances of how an individual patient’s brain function is affected by such injuries. A “mild” TBI, such as a concussion, can lead to significant cognitive, emotional, and physical impairments that profoundly disrupt a person’s daily life, challenging the assumption that the term indicates a lack of serious consequences. On the other hand, a “severe” TBI might suggest universally grave outcomes, whereas some individuals may experience varying degrees of recovery and adaptation, while others survive in a vegetative state. These labels are not helpful in understanding the true functional impact of TBI on patients’ lives.

That said, in the most extreme cases, patients may experience paralysis, coma, or a persistent vegetative state showing no signs of awareness for an indefinite period.

Most TBI cases will range from mild to moderate with patients experiencing some or all of the following signs and symptoms:

Physical Symptoms of Traumatic Brain Injury

Headache(s)
Sensitivity to light or sound
Dilation of one or both pupils
Nausea or vomiting
Change in eating or nursing habits
Loss of consciousness
Fatigue
Inability to awaken or other changes in sleeping patterns, such as trouble falling or staying asleep, or sleeping more or less than usual
Dizziness
Loss of balance and coordination, including trouble walking
Ringing in ears
Double or blurred vision
Slurred speech
Numbness or tingling in extremities
Spasticity
Muscle weakness
Seizures

Cognitive Symptoms of Traumatic Brain Injury

Feeling foggy or confused
Slow thinking or processing
Memory issues
Inability to concentrate
Poor judgment
Falling behind in school

Emotional and Behavioral Symptoms of Traumatic Brain Injury:

Feeling more sad, nervous, irritable, restless, impatient, or fussy than normal
Lack of motivation or interest in performing normal activities
Inability to tolerate daily routines
Emotional outbursts or unusually bold behavior
In babies and young children, persistent crying and inability to be consoled; loss of interest in favorite toys or activities

Discover the Causes, Symptoms, and Treatments of Traumatic Brain Injuries in Children

Discover the causes, symptoms, and treatments of traumatic brain injuries in children. Learn how to protect your child and recognize early warning signs. For information on understanding symptoms and care needs for very young patients, read “Understanding Traumatic Brain Injuries In Children”.

Learn more

Diagnosis and Treatment

There are a variety of methods used by healthcare professionals to obtain an accurate traumatic brain injury diagnosis, including both physical and neurological clinical evaluations, as well as imaging such as CT scans or MRIs to assess the extent of the injury.

In addition to any abnormalities found on the imaging and evaluation, a healthcare provider will consider other factors, including any extended loss of consciousness, neurological symptoms exhibited at the time of injury, and memory loss resulting from or related to the injury itself.

The healthcare provider team will then classify the injury as mild, moderate, or severe — typically based on the Glasgow Coma Scale — with treatment and follow-up care designed accordingly. That may include any combination of the following procedures and services:

Immediate Care — The priority is always to ensure the patient is breathing and maintaining blood flow to the brain.
Medications — A variety of treatments — including pain relievers, anti-seizure drugs, diuretics, and more — can help manage symptoms such as pain, seizures, or spasticity.
Hospitalization — In severe cases, monitoring and potential surgical intervention may be required.
Rehabilitation — Physical, occupational, and speech therapy can help address any deficits resulting from the injury.

Monitoring — Regular check-ups allow caregivers to monitor the patient’s recovery and address any ongoing issues.
Long-Term Care and Support — Access to support services can help both the patient and family cope with any chronic TBI impacts.

Understanding the Stages of Cognitive Recovery From Traumatic Brain Injury

Every patient and every injury is different. The most widely used tool for assessing cognitive recovery from TBI is The Rancho Los Amigos Cognitive Functioning Scale. Developed in 1972 by Dr. Chris Hagen and his research team at the Downey, CA-based Rancho Los Amigos National Rehabilitation Center, this 10-level scale (outlined below) was created by observing TBI patient behaviors and using them to gauge their cognitive level during various phases of recovery.

The Rancho Los Amigos Cognitive Functioning Scale

Level	Cognitive Response/Need for Assistance	Clinical Features
Level I	No response/total assistance	No response to external stimuli
Level II	Generalized response/total assistance	Responds inconsistently and non-purposefully to external stimuli Responses are often the same regardless of the stimulus applied
Level III	Localized response/total assistance	Responds inconsistently and specifically to external stimuli Responses are directly related to the stimulus Tend to be more responsive to familiar people (friends and family) than to strangers
Level IV	Confused and agitated/max assist	In a hyperactive state with bizarre and non-purposeful behavior Demonstrates agitated behavior that originates more from internal confusion than the external environment
Level V	Confused, inappropriate non-agitated/max assist	Shows an increase in consistency with following and responding to simple commands; responses are non-purposeful and random to more complex commands Behavior and verbalization are often inappropriate; the patient can appear confused and often confabulates Can perform an action or task if it is first modeled or demonstrated for them; they do not yet initiate tasks on their own Memory is severely impaired, and learning new information is difficult Can show agitation to unpleasant external stimuli
Level VI	Confused, appropriate/ mod assist	Able to follow simple commands consistently Able to retain learning for familiar tasks they performed pre-injury (brushing teeth, washing face) but are unable to retain learning for new tasks Demonstrates an increased awareness of self, situation, and environment but unaware of any specific impairments and safety concerns Responses may be incorrect secondary to memory impairments but appropriate to the situation
Level VII	Automatic, appropriate/ min assist	Oriented in familiar settings Able to perform a daily routine automatically with no/minimal confusion Demonstrates carry over for new tasks and learning in addition to familiar tasks Can be superficially aware of diagnosis but unaware of specific impairments Continues to demonstrate a lack of insight, decreased judgment and safety awareness Beginning to show interest in social and recreational activities in structured settings Requires at least minimal supervision for learning and safety purposes
Level VIII	Purposeful, appropriate/ standby assist	Consistently oriented to person, place, and time Can independently carry out familiar tasks in a non-distracting environment Beginning to show awareness of their specific impairments and how they interfere with tasks, but they still require standby assistance with compensatory skills Able to use assistive memory devices to recall a daily schedule Acknowledges other people’s emotional states and require only minimal assistance to respond appropriately Demonstrates improvement of memory and ability to consolidate past and future event Often depressed, irritable, and demonstrates a low frustration threshold
Level IX	Purposeful, appropriate/ standby assist on request	Able to shift between different tasks and complete them independently Aware of and acknowledges impairments when they interfere with tasks Able to use compensatory strategies to cope Able to independently anticipate obstacles that may arise secondary to any lingering impairments Able to consider the consequences of actions and decisions with assistance Continues to demonstrate depression and low frustration thresholds
Level X	Purposeful, appropriate/ modified independent	Able to multitask in many different environments with extra time for task completion or devices to assist Able to create their own methods and tools for memory retention Can independently anticipate obstacles that may occur as a result of their impairments and take corrective actions Able to independently make decisions and act appropriately but may require more time or compensatory strategies May still demonstrate intermittent periods of depression and a lowered threshold for frustration when under stress Able to appropriately interact with others in social situations

Chart Source: Physiopedia, adapted from Lin K., & Wroten, M., Ranchos Los Amigos, 2022

Strategies for the Prevention of Traumatic Brain Injury

Prevention strategies for traumatic brain injuries (TBI) are crucial because they not only protect individuals from the immediate risks of injury but also mitigate the long-term consequences that can significantly impact quality of life. Effective measures—such as wearing helmets, promoting safe sports practices, and improving workplace safety—can reduce the incidence of a TBI and foster a culture of awareness and proactive health management. Let’s look at a few of the most important prevention strategies:

Educate yourself about fall-prevention strategies (e.g., balance exercises) and other important safety practices related to your home, job, and recreational activities.
Ensure that everyone in your family uses a seat belt; properly installed, age-appropriate infant carrier; or child safety seat that meets Federal Motor Vehicle Safety Standards every time they ride in a car. If you have questions about proper installation, there are a variety of information sources (e.g., Safe Kids Worldwide and Buckle Up for Life) and professional technicians you can turn to for help.
Ensure all family members wear a properly fitted helmet certified by the U.S. Consumer Product Safety Commission (CPSC) when engaging in risky activities like biking, skiing, skateboarding, or playing an impact sport like ice hockey or football. Keep in mind that in most cases, different activities require different helmets based on impact resistance needs and other criteria. For guidance and current requirements, visit the CPSC website.
Make environmental modifications in your home, such as removing tripping hazards, and ensure safe play areas by installing child-proof window guards and safety gates on stairways.
Ensure that children live in an environment that is safe and free from abuse. If you need personal assistance or support — or witness a situation in which another child may be in physical danger in their own home — contact the National Domestic Violence Hotline immediately.

Living With TBI

If a loved one just suffered a TBI and has been discharged from the hospital, you’re likely wondering, now what? Not properly knowing how to care for a loved one or fully understanding your legal rights could lead to unnecessary suffering and financial distress. For a full discussion on this topic, read Caring for a Loved One With Traumatic Brain Injury

TBI Frequently Asked Questions

What are the long-term effects of TBI?

In some cases, patients recover from mild head trauma injuries and return to their normal level of health and activity in relatively short order. In other instances, however, there can be lingering effects from more severe TBIs, which need to be evaluated and addressed on a case-by-case basis.

Note: Even seemingly mild injuries like concussions can cause symptoms that linger for decades, and it’s important not to dismiss the red flags that signal the patient may be suffering from long-term post-concussion syndrome.

They include:

Cognitive Impairments — Problems may linger with memory, attention, and executive function.

Behavioral Changes — The patient may exhibit long-term increased irritability, impulsivity, or emotional instability that affect their personal and social relationships.

Physical Challenges — A variety of chronic ailments can include motor deficits, coordination issues, and chronic pain.
Educational Impact — The patient may also experience difficulty with school performance and have a need for special educational programs and services.

How can I support a loved one with TBI?

Providing support to a loved one with traumatic brain injury (TBI) is a challenging undertaking that can last weeks, months, and — in severe cases — an entire lifetime for those with chronic and severe injuries.
As you might expect, this type of care requires caretakers and family members to have not only a strong grasp of relevant medical knowledge, but also deep reserves of patience and compassion.
While each injury, patient, and long-term outlook is different, there are some general guidelines that can help you and your family support a loved one this emotional journey and achieve the best outcomes for all. Learn more by reading Caring for a Loved One With Traumatic Brain Injury

Are there any recent advancements in traumatic brain injury treatment?

The best practices in TBI treatment based on medical evidence are discussed in an article “Treatment and Rehabilitation for Traumatic Brain Injury: Current Update”, published online by the National Institutes of Health, the primary agency of the U.S. government responsible for biomedical and public health research.

The article provides a comprehensive overview of the management strategies for TBI highlighting its significant public health implications and the need for more effective treatment and rehabilitation. The authors emphasize that timely assessment of TBI symptoms can enhance prognosis and rehabilitation outcomes.
The article discusses the growing incidence of disorders of consciousness in TBI survivors and outlines the importance of structured evaluation methods, including MRI and EEG, to assess consciousness levels. Recommendations for medications, particularly Amantadine, are provided, alongside emerging non-invasive brain stimulation techniques that show promise in improving arousal and consciousness.
Additionally, the article addresses mild TBI and the prevalence of cognitive impairments, anxiety, and post-concussive symptoms that often accompany it. Evidence-based clinical practice guidelines for mild TBI management are reviewed, stressing the need for an interdisciplinary approach to care.
Cognitive rehabilitation is also highlighted as a critical aspect of post-TBI recovery. Methylphenidate, along with other medications, is cited as an effective treatment for cognitive deficits, while non-pharmacological interventions, including virtual reality, are gaining recognition for their positive impact on cognitive function.
The article also explores the high incidence of depression following TBI and the varying effectiveness of pharmacological and psychological interventions. Post-traumatic headache (PTH), the most common complaint after TBI, is examined, with recommendations for management that emphasize the need for further research to refine treatment strategies.
Emerging biomarkers for diagnosing and predicting treatment outcomes in TBI are discussed, with neurofilament light (NfL) showing promise as a reliable indicator of axonal injury.
The article concludes that while progress has been made in the treatment and rehabilitation of TBI, the need for robust evidence through large-scale studies remains vital. The authors advocate for ongoing research efforts to enhance patient care and address the complex challenges associated with traumatic brain injuries, ensuring that management strategies are backed by strong empirical data.

Other recent projects aimed at improving patient care, recovery outcomes, and quality of life include:

Biomarker Identification — New projects like PROCEED TBI from Penn Medicine are using advanced brain imaging and blood biomarkers specific to different types of brain injuries so health care providers can tailor treatments based on the underlying brain damage rather than just symptoms, potentially leading to more effective therapies.
Neuroprotective and Neuroregenerative Therapies — On this front, two treatments are showing early promise in animal studies: Magnesium for reducing excitotoxicity and inflammation; and lithium combined with neural stem cell transplants for neuroprotective effects. To date, neither has proven efficacy in human trials. Source: Frontiers
Wearable Technology — Wearable devices can now continuously monitor the vital signs, physical activity, and cognitive function of patients, allowing for early detection and intervention for complications with the aim of significant improvements in TBI management, treatment plans, and recovery outcomes.

Source: University of Utah, Wearable tech helps concussion patients (2023)

What resources are available for learning more and getting help with TBI?

In addition to our Free Book, Video Library and our 50 State Guide to finding helpful resources that are local to you, here is a list of organizations that specialize in TBI information and support:

Need help investigating your legal rights related to a traumatic brain injury?

Speak to an experienced brain injury attorney team like Cohen, Placitella & Roth.

For five decades, CPR has successfully represented individuals and families in TBI cases working nationwide with qualified co-counsel.

Get a Free Case Evaluation Today

Get Our Free Traumatic Brain Injury Book

To learn more about Traumatic Brain Injury request our comprehensive book, available for free directly to your inbox

Find resources in your state

TraumaticBrainInjury.com has organized a state-by-state guide for those seeking information on advocacy, financial, rehabilitation, and legal resources near them.
Select a State

Learn More

June 3, 2025