Name: 【TED-Ed】What happens when you have a concussion? - Clifford Robbins
Uploaded: 2017-07-30T01:24:05.000Z
Duration: 6 min 16 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

players of sports  and recreational activities

receive between 2.5  and 4 million concussions.

and lies in how the brain responds when something strikes it.

The brain is made of soft fatty tissue, with a consistency something like jello.

Inside its protective membranes and the skull's hard casing,

this delicate organ  is usually well-shielded.

But a sudden jolt can make the brain shift

and bump against  the skull's hard interior,

and unlike jello, the brain's tissue isn't uniform.

It's made of a vast network of 90 billion neurons,

which relay signals through their long axons to communicate throughout the brain

This spindly structure makes  them very fragile

so that when impacted, neurons will stretch and even tear.

That not only disrupts their ability to communicate

but as destroyed axons begin to degenerate,

they also release toxins causing the death of other neurons, too.

This combination of events causes a concussion.

The damage can manifest  in many different ways

problems with memory,  thinking, and sleeping,

which explains why people's experiences of concussions vary so widely.

Luckily, the majority of concussions fully heal

and symptoms disappear within a matter of days or weeks.

Lots of rest and a gradual return to activity

many people have heard that you're not supposed to sleep

shortly after receiving a concussion because you might slip into a coma.

So long as doctors aren't concerned there may also be a more severe brain injury,

there's no documented problem with going to sleep after a concussion.

Sometimes, victims of concussion can experience something

People with PCS may experience constant headaches,

and behavioral symptoms that even affect their personal relationships

Trying to play through a concussion, even for only a few minutes,

or returning to sports too soon after a concussion,

In some cases, a concussion  can be hard to diagnose

because the symptoms unfold slowly over time.

That's often true of  subconcussive impacts

which result from lower impact jolts to the head

This category of injury doesn't cause noticable symptoms right away,

but can lead to severe degenerative brain diseases over time

Take soccer players, who are known for repeatedly heading soccer balls.

Using a technique called Diffusion Tensor Imaging,

we're beginning to find out what effect that has on the brain.

This method allows scientists to find large axon bundles

and see how milder blows might alter them structurally.

In 2013, researchers using  this technique discovered

that athletes who had  headed the ball most,

had damaged the structural integrity of their axon bundles.

The damage was similar to how a rope will fail

when the individual fibers start to fray.

Those players also performed worse on short-term memory tests,

so even though no one suffered full-blown concussions,

these subconcussive hits added up to measurable damage over time.

In fact, researchers know that an overload of subconcussive hits

is linked to a degenerative brain disease known as Chronic Traumatic Encephalopathy,

People with CTE suffer from changes in their mood and behavior

followed by problems with thinking and memory

that can, in some cases, even result in dementia.

Usually, Tau proteins support tiny tubes inside our axons called microtubules.

It's thought that repeated subconcussive hits damage the microtubules,

causing the Tau proteins to dislodge and clump together.

The clumps disrupt transport and communication along the neuron

and drive the breakdown of connections within the brain.

Once the Tau proteins  start clumping together,

and continue to spread  throughout the brain,

The data show that at least among football players,

between 50 and 80% of concussions go unreported and untreated.

Sometimes that's because it's hard to tell

a concussion has occurred  in the first place.

But it's also often due to pressure or a desire to keep going

They still need us to shield  them from harm

Subtitles ListPlay Video

【TED-Ed】What happens when you have a concussion? - Clifford Robbins

anxiety

chronic

technique

stretch