What is a concussion? What to know about Mitch McConnell's brain injury

U.S. Senate minority leader Mitch McConnell, 81, fell Wednesday during a dinner at a Washington hotel. The Kentucky lawmaker is now being treated for a concussion and is being observed at a hospital. 

"He is expected to remain in the hospital for a few days of observation and treatment,"  spokesman David Popp told USA TODAY. "The leader is grateful to the medical professionals for their care and to his colleagues for their warm wishes."

What is a concussion?

A concussion is another name for a traumatic brain injury, which occurs when your head suffers a blow or violent shaking. It impacts what's essentially the central computer of your body and can impact vision, balance, speech, memory, emotions and more.

Concussion symptoms include nausea, feeling groggy, confusion and blurry vision, according to the Centers for Disease Control and Prevention. 

When a concussion results in persistent ongoing symptoms such as migraines, it is referred to as post-concussion syndrome. Post-concussion syndrome can take years to recover from.

How problematic are brain injuries?

A recent study found that traumatic brain injuries are a significant public health issue in the United States, with 1.5 million occurring annually and 75% classified as mild — at a cost of $17 billion annually.

Because brain injuries or concussions are invisible injuries, it can be hard to properly treat recognize or treat symptoms. About 90% of concussion symptoms, however, usually resolve within 10 to 14 days but may also linger for weeks. Persistent post-concussion syndrome occurs when symptoms persist for more than three months.

Those who suffer multiple head injuries, like athletes and soldiers, are at an increased risk of experiencing post-concussion syndrome. Since a concussion does not typically show up on any imaging, ongoing and long-lasting changes to executive function can be hard to detect. The study found that experts believe the 15% occurrence of post-concussion syndrome underestimates the true number.

Women more likely to get concussions

Research shows women, especially the older they are, are more likely to suffer concussions than men, but the bulk of research has been conducted around male soldiers and athletes. Young people are believed to be less likely to suffer post-concussion syndrome because of their ability for the brain to recover, or a concept known as neuroplasticity.