How to Know If You Have a Concussion

A concussion is classified as a mild traumatic brain injury (TBI) that temporarily disrupts normal brain function. Often, the effects are short-lived, but they can manifest in various ways, including headaches, concentration difficulties, memory problems, balance issues, mood changes, and sleep disturbances.

Concussions are typically the result of a blow to the head or body forceful enough to cause the brain to move rapidly inside the skull. This movement can lead to chemical changes in the brain and sometimes damage brain cells. It’s important to note that not every head or body impact results in a concussion.

While some concussions can cause a brief loss of consciousness, the majority do not. Falls are the most prevalent cause of concussions across all age groups. They are also frequently observed in athletes participating in contact sports like football and soccer. Fortunately, most individuals who experience a concussion make a full recovery.

Recognizing Concussion Symptoms

Concussion symptoms can be subtle and may not appear immediately after the injury. They can emerge over hours or even days and can persist for days, weeks, or occasionally longer. Knowing what to look for is crucial in identifying a concussion.

A hallmark symptom immediately following a mild traumatic brain injury is often a combination of headache, confusion, and amnesia, specifically retrograde amnesia, which involves forgetting the event that caused the concussion.

Physical symptoms of a concussion might include:

Headache: This is one of the most common complaints after a concussion.
Ringing in the ears (Tinnitus): Experiencing sounds like buzzing, ringing, hissing, or roaring 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 focusing or seeing clearly.

Other symptoms that indicate a concussion can affect cognitive and sensory functions:

Confusion or Feeling in a Fog: Difficulty thinking clearly, feeling disoriented, or like you’re in a haze.
Amnesia Surrounding the Event: Not remembering what happened immediately before or after the injury.
Dizziness or “Seeing Stars”: Feeling lightheaded, unsteady, or experiencing visual disturbances.

Witnessing someone who has sustained a concussion, you might observe these signs:

Temporary Loss of Consciousness: Although not always present, brief unconsciousness can occur.
Slurred Speech: Difficulty speaking clearly and articulating words.
Delayed Response to Questions: Answering questions slowly or seeming slow to understand.
Dazed Appearance: Looking blank or confused.
Forgetfulness and Repetition: Asking the same question repeatedly due to memory issues.

Some concussion symptoms are immediate, while others may be delayed, appearing days after the initial injury. These delayed symptoms can include:

Trouble with Concentration and Memory: Difficulty focusing, learning new information, or remembering recent events.
Irritability and Personality Changes: Becoming easily agitated, frustrated, or experiencing shifts in mood and behavior.
Sensitivity to Light and Noise: Increased discomfort or pain from bright lights or loud sounds.
Sleep Disturbances: Trouble falling asleep, staying asleep, or sleeping more than usual.
Emotional Changes and Depression: Feeling unusually emotional, sad, or hopeless.
Changes in Taste and Smell: Alterations in the ability to taste or smell.

Recognizing Concussion Symptoms in Children

Concussions in infants and toddlers can be particularly challenging to identify because they cannot verbally express their symptoms. Clues that a young child may have a concussion include:

Dazed Appearance: Appearing confused or out of it.
Listlessness and Tiring Easily: Lacking energy and becoming fatigued quickly.
Irritability and Crankiness: Being more fussy, easily upset, and generally unhappy.
Loss of Balance and Unsteady Walking: Difficulty maintaining balance or walking normally.
Excessive Crying: Crying more than usual and being difficult to soothe.
Changes in Eating or Sleeping Patterns: Refusing to eat, eating less, or changes in typical sleep routines.
Lack of Interest in Favorite Toys: Showing less engagement or enjoyment in activities and toys they usually like.
Vomiting: Throwing up.

When to Seek Medical Attention

It’s vital to know when to seek medical help after a head injury.

Consult a healthcare professional within 1 to 2 days if:

You or your child has experienced any head injury, even if you don’t believe emergency care is necessary. A healthcare provider can assess the situation and provide guidance.

Children and adolescents should be evaluated by a healthcare professional specifically trained in managing pediatric concussions.

Seek emergency care immediately for an adult or child who experiences a head injury and any of the following symptoms:

Repeated Vomiting or Nausea: Persistent or forceful vomiting.
Loss of Consciousness Longer Than 30 Seconds: Prolonged unconsciousness after the injury.
Worsening Headache: A headache that intensifies over time.
Fluid or Blood Draining from the Nose or Ears: Any discharge of clear fluid or blood.
Vision or Eye Changes: Pupils becoming larger than normal, unequal in size, or any other visual disturbances.
Persistent Ringing in the Ears: Ringing that doesn’t subside.
Weakness in Arms or Legs: Loss of strength or feeling in limbs.
Behavioral Changes: Unusual or erratic behavior.
Confusion or Disorientation: Not knowing people, places, or being generally confused.
Slurred Speech or Speech Changes: Difficulty speaking or changes in speech patterns.
Obvious Changes in Mental Function: Decline in cognitive abilities or mental processing.
Changes in Physical Coordination: Stumbling, clumsiness, or balance problems.
Seizures or Convulsions: Uncontrolled muscle spasms or shaking.
Persistent or Recurring Dizziness: Dizziness that doesn’t go away or comes back after resolving.
Worsening Symptoms: Any concussion symptoms that get worse over time.
Large Head Bumps or Bruises: Significant swelling or bruising on the head, especially around the eyes (raccoon eyes) or behind the ears (Battle’s sign). These are particularly concerning in infants under 12 months old.

Concussion Symptoms in Athletes: A Special Note

Under no circumstances should an athlete return to play or vigorous activity immediately following a concussion. Experts universally recommend that athletes of all ages, from children to adults, who sustain a concussion should not return to play on the same day as the injury. If a concussion is even suspected, it’s crucial to refrain from any activity that could put the athlete at risk of further injury. A gradual and supervised return to learning and physical activity is essential and should be guided by a healthcare professional.

What Causes a Concussion?

Types of Concussion Injuries

Concussions are frequently caused by falls, direct blows to the head, car accidents, and blast injuries from explosions. The specific way these injuries impact the brain can vary, leading to different types of concussions.

During a concussion, the brain, which is cushioned by cerebrospinal fluid, moves rapidly back and forth within the skull. This forceful movement occurs when the head and neck or upper body experience a sudden and violent blow. It can also result from rapid acceleration or deceleration of the head, such as in a car crash, a fall from a bicycle, or a collision during sports.

These abrupt movements can injure brain tissue and disrupt normal brain function, typically for a short duration. In some cases, even a mild traumatic brain injury can cause bleeding in or around the brain. This bleeding can lead to prolonged drowsiness, confusion, and in severe instances, death. Therefore, anyone who sustains a brain injury needs close monitoring in the hours following the incident and should seek immediate emergency care if their symptoms worsen.

Risk Factors for Concussion

Certain events and factors can elevate the risk of experiencing a concussion:

Activities Leading to Falls: Especially prevalent in young children and older adults, falls are a major cause.
High-Risk Sports: Participation in contact sports like football, hockey, soccer, rugby, and boxing significantly increases risk.
Lack of Proper Safety Equipment and Supervision: Not using helmets or other protective gear and inadequate supervision during high-risk sports.
Motor Vehicle Accidents: Car, motorcycle, bicycle, and pedestrian accidents.
Military Combat: Exposure to explosions and combat situations.
Physical Abuse: Acts of violence that involve blows to the head.
Previous Concussion: Having had a concussion in the past increases the likelihood of future concussions.

Potential Complications of Concussion

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

Post-Traumatic Headaches: Headaches can persist for days to weeks after the injury.
Post-Traumatic Vertigo: A sensation of spinning or dizziness that can last for days or weeks.
Persistent Post-Concussive Symptoms (Post-Concussion Syndrome): In some individuals, symptoms like headaches, dizziness, and cognitive difficulties can last longer than expected. If these persist beyond 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 (those without immediate symptoms).
Second Impact Syndrome: A rare but life-threatening condition where a second concussion occurs before the symptoms of a previous concussion have resolved. This can lead to rapid and severe brain swelling and potentially death. It underscores the importance of complete recovery before returning to activities that carry a risk of head injury.

Concussion Prevention Strategies

Taking preventive measures can significantly reduce the risk of concussions:

Wear Protective Gear in Sports and Recreation: Always use appropriate, well-fitting, and properly maintained protective equipment, including helmets, when participating in sports and recreational activities. Follow rules and practice good sportsmanship. Helmets are crucial for activities like bicycling, motorcycling, and snowboarding.
Use Seat Belts: Always buckle up when in a vehicle to prevent serious injuries, including head injuries, during accidents.
Make Your Home Safe: Ensure your home is well-lit and free of tripping hazards. Falls at home are a major cause of head injuries.
Protect Children: Install safety gates on stairways and window guards to minimize the risk of falls in children.
Regular Exercise: Strengthening leg muscles and improving balance through regular exercise can reduce the risk of falls.
Concussion Education: Educating coaches, athletes, parents, and the general public about concussion recognition, management, and prevention is vital to increase awareness and promote safety.

By Mayo Clinic Staff

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Jan. 12, 2024

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