Name: 言語と脳。失語症と分割脳の患者 (Language and the brain: Aphasia and split-brain patients)
Uploaded: 2021-01-14T05:40:31.000Z
Duration: 6 min 11 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

You may perceive language as one big function

In this video, we'll discuss how your brain speaks

happens when those functions are disrupted.

First, let's go over some basic neuroanatomy.

Lefties and ambidextrous folks are somewhat more

in the right hemisphere, but still about 70% of them

will have language centralized in the left hemisphere.

the two main areas associated with language

and Wernicke's area, which helps us understand language.

Broca's area is in the frontal lobe, usually

the left frontal lobe, and it's responsible for language

This is called non-fluent aphasia, or Broca's aphasia.

I remember this by thinking that Broca's aphasia means

"broken speech," and aphasia is just any type of disorder

When Wernicke's area, back in the temporal lobe, is damaged,

in fact, words kind of just tumble out of them--

but the words that do come out don't make any sense.

It's like listening to a bunch of nonsense sentences.

People with Wernicke's aphasia, which is also sometimes called

"fluent aphasia," can also have trouble understanding

And when both Broca's aphasia and Wernicke's aphasia

called "global aphasia," because it globally affects language

instead of only affecting a subsection of it.

Broca's area and Wernicke's area are connected in the brain

by a bundle of nerve fibers called the arcuate fasciculus.

found in deaf people who know sign language.

So it's not specific to a spoken language,

but the brain adapts to use whatever modality

experience something called "conduction aphasia."

Their ability to conduct information between listening

them unable to repeat things, even though they

language-specific functions you do every day,

you might wonder how many different types of aphasia

We have agraphia, which is the inability to write,

anomia, which is the inability to name things,

and other specific difficulties in reading, spelling, grammar,

you may not even realize that you do effortlessly

But Broca's apahasia and Wernicke's aphasia

Language is just one example of how our brain works in general.

Big tasks are subdivided into small tasks, which are then

spread around in different parts of the brain.

because it means if you have very localized or very specific

brain damage, then you probably won't completely

lose your ability to perform some highly important function

In fact, when functions are divided like that,

that affect the left hemisphere of their brain,

they may have trouble speaking or something

right after the stroke, but over time and with proper therapy,

other speech-related parts of their brain

by creating new connections between neurons.

Building these connections, in combination

with some recovery of the originally damaged part

of the brain, can help these people speak again

And the brain's ability to adapt and move functions to new parts

is called neural plasticity, or synaptic plasticity.

The neurons are plastic, or flexible enough,

to learn new routes and connections, thus allowing

over functions that the damaged parts previously performed.

Even with perfectly functioning hemispheres,

you might still have trouble naming objects.