8 Concussion Symptoms You Should Know

Having a concussion can be more than just losing consciousness.

Anytime you receive a blow or jolt to your head, you have a chance of suffering a concussion. The blow to the head can be from falling off a bike, after an auto accident, or while playing sports, A concussion is a brain injury that results in the short-term loss of normal brain functioning.

Even though this type of injury usually resolves within a month (approximately two to four weeks), for some people, concussions may have long-term consequences after recovery. Those consequences include mood swings, fatigue, insomnia, or personality changes.

Unfortunately, concussions don't show up on MRIs or CT scans. And as of 2022, there's no definitive, objective exam for diagnosing concussions. So, recognizing the symptoms can help you be aware of when to seek medical attention if a healthcare provider isn't already a part of your care.

"If you have a certain set of symptoms, you can be reasonably certain you have a concussion," explained Kenneth Podell, PhD, a neuropsychologist at the Houston Methodist Department of Neurology. 

It's also important to realize that symptoms may be sudden, acute, or subtler and worsen over the next few days, Dr. Podell added.

So, to ensure you get the proper medical attention after a concussion, here are eight symptoms of concussions you should know.

01 of 08

A Persistent Headache

Hitting your head or getting hit on the head is bound to hurt and leave you with a headache.

However, if you have a concussion, that headache is persistent. Barry Kosofsky, MD, PhD, a pediatric neurologist at Weill Cornell Medicine in New York, explained that it will likely feel different than bumping your head and continuing on with what you were doing.

"It's like a pressure headache that is nearly constant. It may get worse when you lie down and a little better when you stand up," explained Dr. Kosofsky. "It also is inducible by increased blood flow to the brain. So doing mental or physical activities that bring more blood into the brain will cause pain."

Of note, headaches from concussions are usually temporary. However, if you do experience a headache after a trauma that does not resolve after a few days or one that gets worse over time, immediately talk to a healthcare provider.

02 of 08

Altered State of Consciousness

One of the tell-tale signs of a concussion is an immediate, altered state of consciousness, usually accompanied by many other issues. Often appearing over minutes, hours, or days later, those issues include vision changes, difficulties with concentration, dizziness, and memory loss, among others.

So, a concussion may be the issue if you are knocked out—or awaken without remembering how you ended up on the ground while alone. 

However, it's also possible to have a concussion even if you aren't knocked out entirely. And important to know, the level of consciousness doesn't determine how bad a concussion is. 

"Interestingly, being knocked out doesn't mean you have a more severe concussion than if you weren't knocked unconscious," explained Chris Hummel, clinical professor and chair of Ithaca College's Department of Exercise and Sport Sciences in South Hill, N.Y.

03 of 08

Dizziness, Feeling Off-Balance, or Nausea

Being dizzy or off balance is a common symptom of concussion, so balance testing is a standard assessment tool for diagnosing the injury and evaluating recovery.

Hummel explained that if your head is spinning and you're stumbling around, those red flags signal concussion. 

But even subtle symptoms like feeling unsteady on your feet can indicate a brain injury. In some cases, you may also feel sick or vomit after hitting your head—both of which are symptoms of a concussion.

04 of 08

Cognitive Problems

If a person has a concussion, they're likely to experience immediate cognitive issues. Feeling foggy or confused are signs of trauma, according to Dr. Podell. And as previously noted, an individual might have problems with concentration or memory.

The effects can be profound, like not knowing which way is home or more subtle problems with processing information. 

However, any cognitive issues associated with a concussion typically improve soon after or within a few weeks of the injury.

05 of 08

Blurry Vision or Eyes Hurting From Bright Lights

You may have a concussion if you're having trouble focusing your eyes after experiencing trauma to the head. According to a 2017 study, double or blurry vision and light sensitivity are common symptoms of concussions.

"If all of a sudden the world seems too bright, and light is really bothering you, that's a sign of concussion," noted Hummel.

But if you're experiencing problems with your vision that comes and goes, including reoccurring double vision, see a healthcare provider as soon as possible. That type of vision problem could signify a serious condition requiring immediate treatment.

06 of 08

Feeling Anxious, Irritable, or Just Not Like Yourself

Feeling anxious is a common symptom of depression, as are other personality changes like irritability. A concussion can also cause someone to become more irritable, and usually happens within a few days of the injury and occurs with other concussion symptoms.

If you don't notice it yourself, pay attention if others point out any personality changes, Hummel noted.

"Someone who knows you well can pick out subtle changes in your personality like you're usually pretty happy-go-lucky, but now you're more quiet and withdrawn—that can signal a brain injury," added Hummel. Personality changes will typically be present with other concussion symptoms.

07 of 08


Fatigue is a frequently-reported symptom for people with a traumatic brain injury (TBI). It takes a lot of energy to heal an injured brain. Hence, it's common to feel drowsy, listless, and downright lethargic afterward. 

"Physical and cognitive rest during the first 24 to 48 hours is essential for proper concussion healing," Hummel said.

Healthcare providers will let you know how quickly you can return to your usual activities following the post-concussion rest period and usually it's a gradual return to those activities.

Hummel also recommended finding someone to stay with you during the first 24 hours after the injury if you live alone. That's in case you develop symptoms of a life-threatening hematoma (a blot clot), which can cause a loss of consciousness, inability to be awakened, or a severe worsening headache.

08 of 08

Sleep Issues

Though you may feel totally wiped out, you may also find that you can't sleep well at night after a concussion. 

Sleep issues following brain injuries are relatively common. A 2016 study found that between 30% and 70% of people reported having problems with sleep after experiencing TBI.

A Quick Review

A concussion requires medical attention and there are symptoms of a trauma that you'll want to pay special attention to, such as:

  • Slurred speech
  • Weakness or numbness
  • Pupil size differences in the eyes
  • A headache that continues to get worse
  • Decreased coordination
  • Drowsiness or an inability to remain awake
  • Repetitive vomiting or nausea
  • Convulsions or seizures
  • Unusual behavior

For infants and toddlers, other symptoms to look out for beyond the ones listed include the child does not stop crying, cannot be calmed, or refuses to eat or nurse. If any of these symptoms occur, immediately visit a healthcare provider.

Finally, trust your instincts—don't second-guess yourself—when it comes to your brain, Hummel added. Symptoms of concussions can be obvious and show up immediately.

"If you've hit your head hard and feel off, and it crosses your mind that you could have a concussion, chances are pretty good that you do. Go get yourself checked out to be safe," Hummel recommended.

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6 Sources
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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