What is a Concussion? Understanding Mild Traumatic Brain Injury, Symptoms, and Recovery

A concussion is classified as a mild traumatic brain injury (TBI) that temporarily disrupts normal brain function. Often resulting from a blow to the head, a concussion can lead to a range of short-term effects, impacting everything from your memory and concentration to your balance, mood, and sleep patterns. While the effects are usually temporary, understanding What A Concussion Is, recognizing its symptoms, and knowing when to seek medical attention are crucial for proper care and recovery.

It’s important to note that a concussion doesn’t always involve losing consciousness. In fact, most concussions occur without any loss of awareness. The injury happens because of a force transmitted to the head, causing the brain to move rapidly within the skull. This movement can stretch and damage brain cells, leading to the symptoms we associate with concussions. Falls are a leading cause of concussions across all age groups. Concussions are also frequently seen in contact sports like football and soccer. Fortunately, with appropriate management and rest, the majority of individuals who experience a concussion make a full recovery.

Recognizing Concussion Symptoms

Concussion symptoms can be easily missed, as they can be subtle and may not appear immediately after the injury. Sometimes, symptoms emerge hours or even days later. These symptoms can persist for varying durations, from days to weeks, and in some cases, even longer.

A hallmark symptom of a concussion is amnesia, or memory loss, particularly surrounding the event that caused the injury. Confusion and headache are also common immediate indicators of a mild traumatic brain injury.

Physical Symptoms of a Concussion:

Headache: This is often the most immediate and common symptom.
Ringing in the ears (Tinnitus): An unwanted noise, like ringing, buzzing, or hissing, in one or both ears.
Nausea: Feeling sick to your stomach.
Vomiting: Throwing up.
Fatigue or Drowsiness: Feeling unusually tired or sleepy.
Blurred Vision: Difficulty seeing clearly.

Cognitive and Sensory Symptoms:

Confusion or Feeling in a Fog: Difficulty thinking clearly, feeling disoriented or detached.
Amnesia: Memory loss, typically surrounding the event that caused the concussion.
Dizziness or “Seeing Stars”: Feeling lightheaded, unsteady, or experiencing visual disturbances.

Observable Symptoms (What a Witness Might See):

Temporary Loss of Consciousness: Although not always present, this can occur.
Slurred Speech: Difficulty speaking clearly and articulating words.
Delayed Response to Questions: Slow or hesitant responses when asked questions.
Dazed Appearance: Appearing confused, blank, or glassy-eyed.
Repetitive Questioning: Asking the same question repeatedly due to forgetfulness.

Delayed Concussion Symptoms:

Some concussion symptoms may not be immediately apparent and can develop over time, sometimes days after the initial injury. These can include:

Concentration and Memory Problems: Difficulty focusing, remembering things, or learning new information.
Irritability and Personality Changes: Increased agitation, mood swings, or shifts in personality.
Sensitivity to Light and Noise (Photophobia and Phonophobia): Discomfort or pain from normal levels of light and sound.
Sleep Disturbances: Difficulty falling asleep, staying asleep, or changes in sleep patterns.
Emotional Changes: Feeling more emotional, sad, anxious, or depressed.
Changes in Taste and Smell: Alterations in the senses of taste and smell.

Concussion Symptoms in Children

Identifying concussions in infants and toddlers can be more challenging as they cannot verbally express how they feel. Parents and caregivers need to be aware of subtle clues that may indicate a concussion in young children:

Dazed Appearance: Looking confused or out of it.
Listlessness and Tiring Easily: Appearing unusually sluggish, lacking energy, or tiring more quickly than usual.
Irritability and Crankiness: Becoming more fussy, easily upset, or generally irritable.
Loss of Balance and Unsteady Walking: Difficulty with coordination, stumbling, or walking unsteadily.
Excessive Crying: Crying more than usual or inconsolable crying.
Changes in Eating or Sleeping Patterns: Refusing to eat, changes in appetite, or alterations in typical sleep routines.
Lack of Interest in Favorite Toys: Reduced engagement or disinterest in toys or activities they usually enjoy.
Vomiting: Throwing up.

When to Seek Medical Attention for a Concussion

It’s essential to know when to seek professional medical advice after a head injury.

Seek medical consultation within 1 to 2 days if:

You or your child experiences any head injury, even if you don’t believe it’s severe or require emergency care. It’s always best to have a healthcare professional assess the situation.
For children and adolescents, it is particularly important to see a healthcare professional who is specifically trained in evaluating and managing pediatric concussions.

Go to the emergency room immediately or call for emergency services for an adult or child who sustains a head injury and exhibits any of these danger signs:

Repeated Vomiting or Nausea: Persistent vomiting or nausea that doesn’t subside.
Loss of Consciousness Lasting Longer Than 30 Seconds: Prolonged unconsciousness after the injury.
Worsening Headache: A headache that progressively intensifies over time.
Fluid or Blood Draining from the Nose or Ears: Clear or bloody discharge from the nose or ears.
Vision or Eye Changes: Pupils that are larger than normal, unequal in size, or other visual disturbances.
Persistent Ringing in the Ears: Ringing in the ears that does not go away.
Weakness in the Arms or Legs: New onset of weakness or numbness in the limbs.
Behavioral Changes: Unusual or significant changes in behavior.
Confusion or Disorientation: Increased confusion, not knowing people or places.
Slurred Speech or Speech Changes: Difficulty speaking clearly or other changes in speech patterns.
Obvious Changes to Mental Function: Decline in cognitive abilities or mental processing.
Changes in Physical Coordination: Stumbling, clumsiness, or difficulty with balance.
Seizures or Convulsions: Uncontrolled muscle spasms or jerking movements.
Persistent or Recurring Dizziness: Dizziness that doesn’t resolve or comes and goes.
Symptoms Worsening Over Time: Any concussion symptoms that are getting progressively worse.
Large Head Bumps or Bruises: Significant swelling or bruising on the head, particularly around the eyes (raccoon eyes) or behind the ears (Battle’s sign), especially concerning in infants under 12 months.

Concussion Symptoms in Athletes: Return to Play

It is absolutely critical that athletes do not return to play or any vigorous physical activity immediately after a concussion. Medical and sports experts universally recommend that athletes of all ages – adults, children, and adolescents – who have sustained a concussion should not return to play on the same day as the injury. Even if a concussion is suspected, it’s crucial to refrain from activities that carry a risk of further head injury.

A gradual return to both learning and physical activity is essential and should be individualized based on the athlete’s specific symptoms and recovery progress. This return must always be supervised by a qualified healthcare professional to ensure the athlete’s safety and prevent further injury.

Causes of Concussions

Concussions are primarily caused by a direct blow to the head, or indirectly when force to another part of the body causes the head and brain to move rapidly. Common scenarios leading to concussions include:

Falls: Falls, especially in young children and older adults, are a major cause of head injuries and concussions.
Sports Injuries: Contact sports like football, soccer, hockey, boxing, and rugby have a higher risk of concussions due to collisions and impacts.
Motor Vehicle Accidents: Car accidents, bicycle accidents, and pedestrian accidents can result in significant head trauma.
Blast Injuries: Explosions, particularly in military settings, can cause concussions.
Assaults and Physical Violence: Being struck in the head can lead to concussion.

During a concussion, the brain, which is cushioned by cerebrospinal fluid, moves forcefully back and forth inside the skull. This rapid movement can occur from a direct impact to the head, neck, or upper body, or from sudden acceleration or deceleration, such as in a car crash. This movement causes the brain to collide with the inner walls of the skull, leading to bruising, stretching, and damage to brain cells and disruption of normal brain function. While most concussions are mild and temporary, in some cases, a concussion can lead to bleeding in or around the brain, which can result in more severe complications, including prolonged drowsiness, confusion, and in rare instances, death. Therefore, anyone who experiences a head injury needs to be closely observed in the hours following the injury, and immediate emergency medical attention is necessary if symptoms worsen.

Risk Factors for Concussion

Certain factors and events can increase the likelihood of experiencing a concussion:

Age: Young children and older adults are at higher risk of falls, a leading cause of concussions.
Participation in High-Risk Sports: Playing contact sports significantly increases concussion risk.
Lack of Proper Safety Equipment and Supervision: Not using helmets or other protective gear in sports and recreational activities, and inadequate supervision, raise the risk.
History of Previous Concussion: Having had a concussion in the past increases the risk of future concussions.
Auto Accidents: Being involved in car, pedestrian, or bicycle accidents.
Military Service: Military personnel, particularly those in combat roles, are at risk due to blast injuries.
Physical Abuse: Victims of physical abuse are at risk of head injuries.

Potential Complications of Concussion

While most people recover fully from a concussion, some complications can arise:

Post-Traumatic Headaches: Headaches that persist for days or weeks after the concussion are common.
Post-Traumatic Vertigo: A sensation of spinning or dizziness that can last for days or weeks following the injury.
Persistent Post-Concussive Symptoms (Post-Concussion Syndrome): A subset of individuals experience prolonged symptoms, including headaches, dizziness, and cognitive difficulties, lasting beyond the expected recovery period. If these symptoms last longer than three months, it’s termed persistent post-concussive syndrome.
Effects of Multiple Brain Injuries: Research is ongoing into the long-term effects of repeated head injuries, including subconcussive injuries (head injuries that don’t cause immediate symptoms). The cumulative impact of these injuries is still being investigated.
Second Impact Syndrome: A rare but life-threatening complication where a second concussion occurs before the symptoms of a previous concussion have resolved. This can lead to rapid and severe brain swelling and can be fatal. This underscores the importance of complete recovery before returning to activities that carry a risk of head injury, especially for athletes.

Concussion Prevention Strategies

Taking proactive steps can significantly reduce the risk of concussions:

Wear Protective Gear: Always use appropriate protective equipment during sports and recreational activities. This includes helmets for biking, skateboarding, skiing, snowboarding, and contact sports. Ensure equipment fits properly, is well-maintained, and worn correctly. Follow safety rules and practice good sportsmanship.
Buckle Up: Consistently wearing seat belts while driving or riding in a vehicle significantly reduces the risk of serious injuries, including head injuries, in case of a car accident.
Home Safety Measures: Make your home environment safer to prevent falls. Ensure adequate lighting, remove tripping hazards from floors, and install handrails on stairs. Falls at home are a major cause of head injuries.
Childproofing: Take measures to protect children from falls at home. Install stair gates and window guards, and ensure safe play areas.
Regular Exercise: Engage in regular exercise to strengthen leg muscles and improve balance, which can help prevent falls.
Concussion Education: Promote concussion awareness and education among coaches, athletes, parents, and the community. Educating people about concussion symptoms, risks, and prevention strategies is vital. Encourage good sportsmanship and safe play practices.

By understanding what a concussion is, recognizing its symptoms, and implementing preventive measures, we can work towards minimizing the impact of these injuries and promoting brain health and safety.

By Mayo Clinic Staff

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