TED2009
Oliver Sacks: What hallucination reveals about our minds
オリバー・サックス： 幻覚が解き明かす人間のマインド
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神経科医であり作家でもあるオリバー・サックスがシャルル・ボネ症候群 ‐視覚障害者に生じる正常人が経験する幻覚症状の一種 ‐について語ります。自身の患者が体験した幻覚を心温まる細部に渡って描写しながら、あまり社会には知られていないこの現象の生態学へと案内します。
Oliver Sacks - Neurological anthropologist
Since "Awakenings" stormed the bestseller lists (and the silver screen), Oliver Sacks has become an unlikely household name, single-handedly inventing the genre of neurological anthropology. Full bio
Since "Awakenings" stormed the bestseller lists (and the silver screen), Oliver Sacks has become an unlikely household name, single-handedly inventing the genre of neurological anthropology. Full bio
Double-click the English transcript below to play the video.
00:12
We see with the eyes,
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人は目だけではなく
00:15
but we see with the brain as well.
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脳でも見ています
00:18
And seeing with the brain is often called imagination.
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想像は脳で見るものです
00:22
And we are familiar with the landscapes of our own imagination,
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想像が描き出す心象は馴染みがあるでしょう
00:27
our inscapes. We've lived with them all our lives.
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どんな人だって想像はしますから
00:31
But there are also hallucinations as well,
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しかし 幻覚もあります
00:35
and hallucinations are completely different.
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幻覚は全く異なるもので
00:38
They don't seem to be of our creation.
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我々の創造ではありません
00:40
They don't seem to be under our control.
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抑制もできません
00:42
They seem to come from the outside,
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幻覚は外から現れて
00:44
and to mimic perception.
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現実と区別がつきにくい
00:47
So I am going to be talking about hallucinations,
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その幻覚について話をします
00:51
and a particular sort of visual hallucination
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私の患者が体験した－
00:55
which I see among my patients.
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特殊な幻視を紹介します
01:00
A few months ago, I got a phone call
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数か月前に電話がありました
01:04
from a nursing home where I work.
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私が働く老人ホームからです
01:06
They told me that one of their residents, an old lady in her 90s,
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入居中の90代の女性が
01:11
was seeing things,
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幻覚を見ているので
01:13
and they wondered if she'd gone bonkers
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気が狂ったのではないか と
01:16
or, because she was an old lady,
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または 高齢のために
01:18
whether she'd had a stroke, or whether she had Alzheimer's.
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脳卒中かアルツハイマーではないか と
01:21
And so they asked me if I would come and see Rosalie,
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それで診に来てほしいと頼まれました
01:26
the old lady.
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ロザリーおばあさんです
01:28
I went in to see her.
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診に行ったら
01:30
It was evident straight away
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彼女が正気なのは
01:32
that she was perfectly sane
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明らかでした
01:35
and lucid and of good intelligence,
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頭ははっきりしていて 理解力もある
01:38
but she'd been very startled and very bewildered,
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でも非常に当惑していました
01:42
because she'd been seeing things.
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幻覚が現れるからです
01:45
And she told me --
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事前に聞いていませんでしたが
01:48
the nurses hadn't mentioned this --
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彼女は盲目だったのです
01:50
that she was blind,
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彼女は5年前に
01:52
that she had been completely blind from macular degeneration for five years.
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加齢黄斑変性症のため 失明したのですが
01:57
But now, for the last few days, she'd been seeing things.
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数日前から幻覚を見るようになりました
02:00
So I said, "What sort of things?"
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“何が見える？” と聞くと
02:03
And she said, "People in Eastern dress,
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“東洋風の服を着た人たちが
02:06
in drapes, walking up and down stairs.
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階段を上り下りしている
02:10
A man who turns towards me and smiles.
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私の方を見て微笑んでいる男
02:13
But he has huge teeth on one side of his mouth.
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口の脇から大きな歯が出ているの
02:17
Animals too.
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動物も見える
02:19
I see a white building. It's snowing, a soft snow.
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白い建物 わた雪が降っている
02:22
I see this horse with a harness, dragging the snow away.
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雪かき用ハーネスをつけた馬が見える
02:27
Then, one night, the scene changes.
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そして ある晩 シーンが変わったの
02:31
I see cats and dogs walking towards me.
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猫や犬が寄ってきて
02:33
They come to a certain point and then stop.
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ある程度近づいたら立ち止まる
02:36
Then it changes again.
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そして また変わる
02:38
I see a lot of children. They are walking up and down stairs.
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階段を上り下りしている たくさんの子ども
02:41
They wear bright colors, rose and blue,
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バラ色や青の明るい服を着ている
02:44
like Eastern dress."
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東洋の服のよう”
02:47
Sometimes, she said, before the people come on,
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その人たちが現れる前に
02:50
she may hallucinate pink and blue squares on the floor,
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床に広がるピンクと青の四角い模様が
02:54
which seem to go up to the ceiling.
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天井に上がる幻覚が見えることも
02:57
I said, "Is this like a dream?"
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“夢のような感じ？” と尋ねると
03:01
And she said, "No, it's not like a dream. It's like a movie."
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“いいえ 夢ではなく映画のよう
03:04
She said, "It's got color. It's got motion.
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色もついていて 動きがある
03:07
But it's completely silent, like a silent movie."
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でも無声映画のように音がない”
03:11
And she said that it's a rather boring movie.
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やや退屈な映画だ と
03:13
She said, "All these people with Eastern dress,
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“東洋風の服をまとった人たちは
03:16
walking up and down, very repetitive, very limited."
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上り下りを繰り返すばかりで 行動が限られている”
03:21
(Laughter)
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（笑）
03:23
And she has a sense of humor.
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ユーモアのある女性なんです
03:25
She knew it was a hallucination.
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幻覚だとわかっていても
03:27
But she was frightened. She'd lived 95 years
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怖がっていた 95年の人生で
03:29
and she'd never had a hallucination before.
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幻覚を見たことがなかったから
03:32
She said that the hallucinations were unrelated
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その幻覚は彼女の思考や感覚
03:35
to anything she was thinking or feeling or doing,
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行動と無関係だというのに
03:39
that they seemed to come on by themselves, or disappear.
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やって来ては消えていくようです
03:43
She had no control over them.
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コントロールすることはできず
03:45
She said she didn't recognize
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彼女には幻覚の中の
03:47
any of the people or places
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人物や場所は
03:49
in the hallucinations.
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どれも見覚えがない
03:51
And none of the people or the animals,
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しかも人も動物も
03:53
well, they all seemed oblivious of her.
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彼女に気がついていないようだった
03:57
And she didn't know what was going on.
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彼女は状況が把握できず
03:59
She wondered if she was going mad
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狂ってしまったかと
04:01
or losing her mind.
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心配していました
04:03
Well, I examined her carefully.
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私は入念に診察しました
04:05
She was a bright old lady,
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陽気なおばあさんで
04:07
perfectly sane. She had no medical problems.
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異常はなし 体調良好
04:11
She wasn't on any medications which could produce hallucinations.
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幻覚を引き起こす薬も飲んでいません
04:15
But she was blind.
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盲目ということだけ
04:17
And I then said to her,
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それで 言ったんです
04:19
"I think I know what you have."
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“察しがつきました
04:21
I said, "There is a special form of visual hallucination
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視力低下や失明によって起きる－
04:25
which may go with deteriorating vision or blindness.
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特殊な幻視があるんです”
04:29
This was originally described," I said,
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“これはシャルル ボネという男性が
04:32
"right back in the 18th century,
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18世紀に初めて
04:34
by a man called Charles Bonnet.
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記述した症状です
04:37
And you have Charles Bonnet syndrome.
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あなたはシャルルボネ症候群です
04:40
There is nothing wrong with your brain. There is nothing wrong with your mind.
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脳も精神も正常
04:42
You have Charles Bonnet syndrome."
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シャルルボネ症候群ですよ”
04:45
And she was very relieved at this,
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それを聞いて彼女は安心し
04:48
that there was nothing seriously the matter,
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深刻な問題ではないことにホッとした
04:52
and also rather curious.
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そして むしろ 好奇の目で
04:55
She said, "Who is this Charles Bonnet?"
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“シャルルボネって誰？
04:57
She said, "Did he have them himself?"
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彼にも幻覚が見えたの？” と
05:00
And she said, "Tell all the nurses
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さらには “看護師のみんなに
05:03
that I have Charles Bonnet syndrome."
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私はシャルルボネ症候群だと言ってちょうだい”
05:06
(Laughter)
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（笑）
05:08
"I'm not crazy. I'm not demented. I have Charles Bonnet syndrome."
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“狂ってもボケてもいない シャルルボネ症候群なだけ”
05:12
Well, so I did tell the nurses.
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彼女の言うとおりにしました
05:14
Now this, for me, is a common situation.
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これは よくあるケースです
05:17
I work in old-age homes, largely.
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主として老人ホームで仕事をするので
05:19
I see a lot of elderly people
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高齢者が相手です
05:21
who are hearing impaired or visually impaired.
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聴覚 視覚障害者も多く
05:25
About 10 percent of the hearing impaired people
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聴覚障害者の約１割は
05:27
get musical hallucinations.
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音楽性幻聴が聴こえます
05:30
And about 10 percent of the visually impaired people
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視覚障害者の約１割は
05:33
get visual hallucinations.
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幻視を見ます
05:35
You don't have to be completely blind,
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全盲ではなく
05:37
only sufficiently impaired.
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弱視も含まれます
05:39
Now with the original description in the 18th century,
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18世紀に話を移しますが
05:43
Charles Bonnet did not have them.
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この幻覚症状があったのは
05:45
His grandfather had these hallucinations.
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シャルルボネではなく彼の祖父でした
05:48
His grandfather was a magistrate, an elderly man.
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祖父は高齢の裁判官でした
05:51
He'd had cataract surgery.
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白内障の手術を受け
05:54
His vision was pretty poor.
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視力は相当悪かった
05:56
And in 1759, he described to his grandson
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1759年 彼は自分の幻覚症状を
06:01
various things he was seeing.
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孫に話したのです
06:03
The first thing he said was he saw
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まず彼が話したのは
06:05
a handkerchief in midair.
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宙に浮くハンカチです
06:07
It was a large blue handkerchief
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大判で青地に
06:09
with four orange circles.
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オレンジの丸が4つ
06:11
And he knew it was a hallucination.
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祖父は幻覚だと認識していました
06:14
You don't have handkerchiefs in midair.
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宙に浮くハンカチはありませんから
06:16
And then he saw a big wheel in midair.
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そして宙に浮く大きな車輪を見た
06:20
But sometimes he wasn't sure whether he was hallucinating or not,
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でも 時々 幻覚か否か自信がなかった
06:25
because the hallucinations would fit
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幻覚が身の回りのものと
06:27
in the context of the visions.
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調和しているからです
06:29
So on one occasion, when his granddaughters were visiting them,
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ある日 孫娘が来ていた時
06:32
he said, "And who are these handsome young men with you?"
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“男前の若い衆は誰かね？” と聞きました
06:37
And they said, "Alas, Grandpapa, there are no handsome young men."
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“まぁ お祖父様 そんな人いないわ”
06:41
And then the handsome young men disappeared.
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そうすると その男たちは姿を消しました
06:45
It's typical of these hallucinations
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幻覚ではよくあることです
06:48
that they may come in a flash and disappear in a flash.
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パッと現れ パッと消える
06:51
They don't usually fade in and out.
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徐々に現れたり消えたりしません
06:53
They are rather sudden, and they change suddenly.
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むしろ突然起きるのです
06:56
Charles Lullin, the grandfather,
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シャルルボネの祖父には
06:59
saw hundreds of different figures,
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何百もの人影や形
07:02
different landscapes of all sorts.
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風景が見えました
07:04
On one occasion, he saw a man in a bathrobe smoking a pipe,
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バスローブ姿でパイプを吸う男も見えました
07:08
and realized it was himself.
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それは彼自身だったのです
07:11
That was the only figure he recognized.
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見覚えのあるのは それだけでした
07:14
On one occasion when he was walking in the streets of Paris,
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ある時 パリの街を歩いていたら
07:18
he saw -- this was real -- a scaffolding.
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目に入った本物の工事現場の足場が
07:21
But when he got back home, he saw a miniature of the scaffolding
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帰宅すると15cmのミニチュアとなって
07:24
six inches high, on his study table.
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書斎の机にのっていました
07:28
This repetition of perception
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映像を繰返し見ることは
07:31
is sometimes called palinopsia.
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反復視と呼ばれます
07:33
With him and with Rosalie,
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シャルルボネの祖父やロザリーに
07:38
what seems to be going on --
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起こっている現象を
07:40
and Rosalie said, "What's going on?" --
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ロザリーに説明しました
07:42
and I said that as you lose vision,
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視力を失うと 脳の視覚部分に
07:45
as the visual parts of the brain are no longer getting any input,
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入る情報が無くなるため
07:48
they become hyperactive and excitable,
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そこが活動過多になります
07:51
and they start to fire spontaneously.
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そして自発的に作用してしまい
07:53
And you start to see things.
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幻覚を見始めるのです
07:56
The things you see can be very complicated indeed.
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時に内容も非常に複雑化します
07:59
With another patient of mine,
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別の患者の体験です
08:03
who, also had some vision,
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その女性は弱視で
08:05
the vision she had could be disturbing.
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彼女に見えるものは厄介でした
08:09
On one occasion, she said she saw
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ある時 彼女はレストランで
08:12
a man in a striped shirt in a restaurant.
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縞模様のシャツを着た男を見た
08:15
And he turned around. And then
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男は彼女の方を振り向き
08:17
he divided into six figures in striped shirts,
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6人に分離して 彼女の方へと
08:20
who started walking towards her.
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歩き始めたのです
08:23
And then the six figures came together again, like a concertina.
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そして 6人はスーっと1人に戻りました
08:26
Once, when she was driving,
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ある時 彼女は夫が運転する－
08:28
or rather, her husband was driving,
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車に乗っていたら
08:30
the road divided into four
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道が4つに分かれました
08:32
and she felt herself going simultaneously up four roads.
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そして彼女も4つに分かれて進む感覚を覚えました
08:36
She had very mobile hallucinations as well.
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動きのある幻覚も見えました
08:41
A lot of them had to do with a car.
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その多くは車に関連したものでした
08:44
Sometimes she would see a teenage boy
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時々彼女はボンネットに座っている―
08:46
sitting on the hood of the car.
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10代の男の子が見えました
08:49
He was very tenacious and he moved rather gracefully
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車にくっつき 道を曲がるたびに
08:51
when the car turned.
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優雅に動くのです
08:53
And then when they came to a stop,
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そして 車が止まると 男の子は
08:56
the boy would do a sudden vertical takeoff, 100 foot in the air,
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30m 真上に急上昇して
08:59
and then disappear.
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姿を消してしまうのです
09:02
Another patient of mine had a different sort of hallucination.
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こんな幻覚を見る患者もいました
09:07
This was a woman who didn't have trouble with her eyes,
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その女性は目には問題ないけれど
09:10
but the visual parts of her brain,
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脳の視覚部分に問題がありました
09:12
a little tumor in the occipital cortex.
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後頭皮質にある小さな腫瘍です
09:15
And, above all, she would see cartoons.
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とりわけ 彼女にはアニメ映像が見えました
09:20
These cartoons would be transparent
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そのアニメは透けて見えるもので
09:25
and would cover half the visual field, like a screen.
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画面のように視野の半分を占めています
09:28
And especially she saw cartoons of Kermit the Frog.
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よく見るのはカエルのカーミットでした
09:34
(Laughter)
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（笑）
09:35
Now, I don't watch Sesame Street,
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私はセサミストリートは見ませんが
09:38
but she made a point of saying,
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彼女は こう主張するんです
09:41
"Why Kermit?" She said, "Kermit the Frog means nothing to me.
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“なぜ？カーミットが出てくる理由がわからない
09:45
You know, I was wondering about Freudian determinants.
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フロイト的な意味が知りたい
09:48
Why Kermit?
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なぜカーミットなの？
09:50
Kermit the Frog means nothing to me."
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何の意味もなさないのに”
09:52
She didn't mind the cartoons too much.
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アニメは我慢できても
09:54
But what did disturb her was she got very persistent
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しつこく出てくるイメージや顔の幻覚に
09:58
images or hallucinations of faces
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彼女もロザリーも困っていました
10:01
and as with Rosalie, the faces were often deformed,
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多くの場合 巨大な歯や目をした
10:04
with very large teeth or very large eyes.
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デフォルメされた顔が見えるからです
10:08
And these frightened her.
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彼女は怖がっていました
10:11
Well, what is going on with these people?
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彼らには何が起きていたのでしょう
10:15
As a physician, I have to try and define what's going on,
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医者である私は患者の症状を見極め
10:18
and to reassure people,
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安心させるのが仕事です
10:20
especially to reassure them that they're not going insane.
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狂ったのではないと伝えるのは特にそうです
10:24
Something like 10 percent, as I said,
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先ほども言いましたが 視覚障害者の
10:27
of visually impaired people get these.
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1割がこの症状を持っています
10:30
But no more than one percent of the people acknowledge them,
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しかし 症状を訴えるのは そのうちの1％以下
10:34
because they are afraid they will be seen as insane or something.
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精神障害だと思われるのが怖いからです
10:37
And if they do mention them to their own doctors
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病院に行っても誤診される－
10:39
they may be misdiagnosed.
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可能性だってあります
10:42
In particular, the notion is that if you see
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特に 幻覚の概念は
10:44
things or hear things, you're going mad,
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気が狂ってる とみられがちです
10:47
but the psychotic hallucinations are quite different.
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しかし 精神病性幻覚は かなり違います
10:50
Psychotic hallucinations, whether they are visual or vocal,
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精神病性の幻視や幻聴の場合
10:53
they address you. They accuse you.
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声をかけてくる 責められる
10:55
They seduce you. They humiliate you.
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誘惑してくる 侮辱される
10:57
They jeer at you.
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馬鹿にされる
11:00
You interact with them.
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巻き込まれてしまいます
11:02
There is none of this quality of being addressed
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シャルルボネ症候群において
11:05
with these Charles Bonnet hallucinations.
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声をかけられることはありません
11:08
There is a film. You're seeing a film which has nothing to do with you,
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自分とは無関係の映画を見るようなもの
11:12
or that's how people think about it.
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そのように 捉えられています
11:15
There is also a rare thing called temporal lobe epilepsy,
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側頭葉てんかん という稀なケースがあります
11:19
and sometimes, if one has this,
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この症状は 過去に遡る感覚や
11:22
one may feel oneself transported back
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以前訪れた場所へ戻るような
11:24
to a time and place in the past.
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感覚が生じることがあります
11:27
You're at a particular road junction.
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ある交差点に立っている
11:29
You smell chestnuts roasting.
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焼き栗の香りがする
11:31
You hear the traffic. All the senses are involved.
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車の音 五感で感じ取れます
11:34
And you're waiting for your girl.
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彼女を待っていた－
11:36
And it's that Tuesday evening back in 1982.
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忘れもしない1982年 あの火曜の夜
11:40
And the temporal lobe hallucinations
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側頭葉に関わる幻覚は
11:42
are all-sense hallucinations,
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すべての感覚に関係しています
11:44
full of feeling, full of familiarity,
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感覚があり 馴染みがあり
11:47
located in space and time,
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場所や時間もはっきりしていて
11:49
coherent, dramatic.
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話に筋が通っていて芝居のよう
11:51
The Charles Bonnet ones are quite different.
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シャルルボネは かなり違います
11:54
So in the Charles Bonnet hallucinations,
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シャルルボネ症候群には
11:58
you have all sorts of levels,
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様々なレベルがあります
12:00
from the geometrical hallucinations --
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幾何学模様の幻覚や
12:02
the pink and blue squares the woman had --
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ロザリーが見たピンクや青の四角
12:05
up to quite elaborate hallucinations
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人や 特に顔の出てくる
12:09
with figures and especially faces.
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とても精緻な幻覚もあります
12:12
Faces, and sometimes deformed faces,
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デフォルメされた顔が現れるのは
12:15
are the single commonest thing
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シャルルボネ症候群で
12:18
in these hallucinations.
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最も一般的です
12:20
And one of the second commonest is cartoons.
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2つ目によくあるのはアニメ
12:23
So, what is going on?
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これは どういうことか
12:26
Fascinatingly, in the last few years,
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面白いことに過去数年の間に
12:28
it's been possible to do functional brain imagery,
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幻覚症状の最中にfMRIを使用して
12:32
to do fMRI on people as they are hallucinating.
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脳機能の画像化が可能になりました
12:36
And in fact, to find that different parts
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実際に幻覚が現れているときに
12:40
of the visual brain are activated
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異なる脳の視覚部分が
12:43
as they are hallucinating.
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活発化することが特定されました
12:45
When people have these simple geometrical hallucinations,
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単純な幾何学模様が現れるときは
12:48
the primary visual cortex is activated.
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一次視覚野が活発化します
12:52
This is the part of the brain which perceives edges and patterns.
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脳は この領域でへりや模様を知覚します
12:55
You don't form images with your primary visual cortex.
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一次視覚野で画像を作りだすのではありません
12:59
When images are formed,
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画像が作りだされるとき
13:02
a higher part of the visual cortex
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高次の視覚野が
13:04
is involved in the temporal lobe.
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側頭葉と作用します
13:06
And in particular, one area of the temporal lobe
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特に 側頭葉の一部は
13:11
is called the fusiform gyrus.
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紡錘状回と呼ばれています
13:13
And it's known that if people have damage in the fusiform gyrus,
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紡錘状回がダメージを受けると
13:17
they maybe lose the ability to recognize faces.
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顔を認識できなくなることがあります
13:21
But if there is an abnormal activity in the fusiform gyrus,
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しかし紡錘状回が異常に働くと
13:25
they may hallucinate faces,
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顔の幻覚を見ることがあります
13:27
and this is exactly what you find in some of these people.
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これが 患者に起きていることだったのです
13:30
There is an area in the anterior part of this gyrus
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この脳回の前方には
13:34
where teeth and eyes are represented,
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歯と目を思い描く領域があります
13:39
and that part of the gyrus is activated
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巨大な歯と目の幻覚が見えるときは
13:42
when people get the deformed hallucinations.
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脳回のその部分が活発化しています
13:46
There is another part of the brain
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脳の別の部分は
13:48
which is especially activated
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アニメが見えるときに
13:50
when one sees cartoons.
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活発になります
13:52
It's activated when one recognizes cartoons,
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アニメを見たり描いたり
13:55
when one draws cartoons, and when one hallucinates them.
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アニメの幻覚発生時に活動しています
13:59
It's very interesting that that should be specific.
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特異性があって興味深いんです
14:02
There are other parts of the brain which are specifically involved
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脳の他の部分では具体的に
14:05
with the recognition and hallucination
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建物 風景の認識や幻覚に
14:07
of buildings and landscapes.
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関連する部分があります
14:10
Around 1970, it was found that there were not only parts of the brain,
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1970年頃 脳の決まった部分のみならず
14:13
but particular cells.
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特定の細胞があることがわかりました
14:15
"Face cells" were discovered around 1970.
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1970年頃 顔細胞が発見されました
14:20
And now we know that there are hundreds of other
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今では何百種類もの
14:22
sorts of cells,
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細胞が発見されています
14:24
which can be very, very specific.
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非常に特有な細胞です
14:26
So you may not only have
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ですから もしかしたら
14:28
"car" cells,
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車細胞だけではなく
14:30
you may have "Aston Martin" cells.
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アストンマーチン細胞があるかも
14:33
(Laughter)
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（笑）
14:35
I saw an Aston Martin this morning.
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今朝アストンマーチンを見たので
14:37
I had to bring it in.
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話したかったんだ
14:39
And now it's in there somewhere.
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既に どこかにあるはずだよ
14:42
(Laughter)
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（笑）
14:45
Now, at this level, in what's called the inferotemporal cortex,
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下側頭葉皮質と呼ばれる このレベルでは
14:49
there are only visual images,
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視覚画像や断片しか
14:52
or figments or fragments.
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処理されません
14:55
It's only at higher levels
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他の感覚が加わってくるのは
14:58
that the other senses join in
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もっと高次の領域です
15:00
and there are connections with memory and emotion.
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そして記憶や感情と関連しています
15:02
And in the Charles Bonnet syndrome,
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シャルルボネ症候群では
15:05
you don't go to those higher levels.
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このレベルまでは達しません
15:07
You're in these levels of inferior visual cortex
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下側頭葉皮質において
15:10
where you have thousands and tens of thousands
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何千も 何百万もの
15:12
and millions of images,
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イメージや断片的な作り事が
15:15
or figments, or fragmentary figments,
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決まった細胞や
15:17
all neurally encoded
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細胞の小さな固まりに
15:19
in particular cells or small clusters of cells.
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神経符号化される部分で生じます
15:23
Normally these are all part of
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通常 これはどれも知覚や想像の
15:26
the integrated stream of perception, or imagination,
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一体化した流れの一部なのです
15:30
and one is not conscious of them.
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人間は意識していません
15:33
It is only if one is visually impaired or blind
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視覚障害者である場合に限り
15:37
that the process is interrupted.
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この過程が中断されます
15:39
And instead of getting normal perception,
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そして 正常な知覚を得る代わりに
15:42
you're getting an anarchic,
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下側頭葉皮質では
15:44
convulsive stimulation, or release,
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その視覚細胞から
15:47
of all of these visual cells
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無秩序で発作的な刺激や
15:49
in the inferotemporal cortex.
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放出が行われているのです
15:51
So, suddenly you see a face. Suddenly you see a car.
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そして突然 顔や車が見えたり
15:54
Suddenly this, and suddenly that.
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色々なものが見えるのです
15:57
The mind does its best to organize
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頭はまとめようとしたり
15:59
and to give some sort of coherence to this,
323
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一貫性をもたせようと頑張りますが
16:02
but not terribly successfully.
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完璧には働きません
16:04
When these were first described,
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この幻覚が初めて発表されたとき
16:06
it was thought that they could be interpreted like dreams.
326
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夢のように解釈できると思われていました
16:10
But in fact people say,
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でも 患者さんは言う
16:12
"I don't recognize the people. I can't form any associations."
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“こんな人たち知らない 関連づけ出来ないわ”
16:15
"Kermit means nothing to me."
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“カーミットなんて私にとって何の意味も持たない”
16:18
You don't get anywhere thinking of them as dreams.
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夢のように考えてもダメなんです
16:23
Well, I've more or less said what I wanted.
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さぁ 私の話はこんなところです
16:28
I think I just want to recapitulate
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要は この幻覚症状は
16:31
and say this is common.
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よくある事なんです
16:33
Think of the number of blind people.
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世界の盲人数を考えてください
16:35
There must be hundreds of thousands of blind people
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このような幻覚症状を持つ盲人は
16:37
who have these hallucinations,
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何十万といるに違いない
16:39
but are too scared to mention them.
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でも怖くて言えないんです
16:41
So this sort of thing needs to be brought into
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ですから このような事実は患者 医者
16:44
notice, for patients, for doctors, for the public.
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世間のために もっと知られるべきなんです
16:50
Finally, I think they are
340
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最後に これは
16:52
infinitely interesting and valuable,
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脳の働きを洞察するには 非常に興味深く
16:55
for giving one some insight as to how the brain works.
342
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貴重な情報だと思っています
16:59
Charles Bonnet said, 250 years ago --
343
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250年前にシャルルボネは
17:02
he wondered how, thinking these hallucinations,
344
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このような幻覚症状を思いながら
17:06
how, as he put it, the theater of the mind
345
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脳の機械仕掛けから 心の劇作品が
17:09
could be generated by the machinery of the brain.
346
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いかに作り出されるのだろうと考えました
17:12
Now, 250 years later,
347
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250年経った現在 私たちは
17:15
I think we're beginning to glimpse how this is done.
348
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真相を究明し始めた と思うのです
17:18
Thanks very much.
349
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どうもありがとう
17:20
(Applause)
350
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（拍手）
17:23
Chris Anderson: That was superb. Thank you so much.
351
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最高だ どうもありがとう
17:26
You speak about these things with so much insight
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洞察力が深くて 患者さんへの
17:28
and empathy for your patients.
353
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共感が感じられました
17:31
Have you yourself experienced any of the syndromes you write about?
354
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そのような経験を ご自身もされたことは？
17:36
Oliver Sacks: I was afraid you'd ask that.
355
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聞かれるだろうと思いましたよ
17:38
(Laughter)
356
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（笑）
17:39
Well, yeah, a lot of them.
357
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けっこう見ます
17:42
And actually I'm a little visually impaired myself.
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実は私も視覚障害者です
17:45
I'm blind in one eye, and not terribly good in the other.
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片目は失明して もう片方も良好ではありません
17:48
And I see the geometrical hallucinations.
360
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幾何学模様の幻覚が見えます
17:52
But they stop there.
361
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他のは見えません
17:54
CA: And they don't disturb you?
362
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不安にかられませんか？
17:56
Because you understand what's doing it, it doesn't make you worried?
363
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どんなことが起きているのか分っておられるから
17:58
OS: Well they don't disturb me any more than my tinnitus,
364
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耳鳴りよりは ましです
18:02
which I ignore.
365
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耳鳴りは無視してますけど
18:05
They occasionally interest me,
366
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幻覚には時折興味が湧くので
18:07
and I have many pictures of them in my notebooks.
367
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ノートにたくさん絵を描いています
18:10
I've gone and had an fMRI myself,
368
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fMRIも使用して視覚野の
18:13
to see how my visual cortex is taking over.
369
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機能も見ました
18:16
And when I see all these hexagons
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六角形や複雑な模様は
18:20
and complex things, which I also have,
371
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眼性片頭痛でも
18:22
in visual migraine,
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見ることがあるのですが
18:24
I wonder whether everyone sees things like this,
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これは普通なのでしょうかね
18:26
and whether things like cave art or ornamental art
374
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そして洞窟壁画や装飾デザインは
18:29
may have been derived from them a bit.
375
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幻覚をヒントに作られたのか興味があります
18:32
CA: That was an utterly, utterly fascinating talk.
376
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非常に興味深い貴重な講話でした
18:34
Thank you so much for sharing.
377
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どうもありがとうございました
18:36
OS: Thank you. Thank you.
378
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ありがとうございました
18:38
(Applause)
379
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（拍手）
ABOUT THE SPEAKER
Oliver Sacks - Neurological anthropologistSince "Awakenings" stormed the bestseller lists (and the silver screen), Oliver Sacks has become an unlikely household name, single-handedly inventing the genre of neurological anthropology.
Why you should listen
Oliver Sacks was a ground-breaking neurologist -- and a gifted storyteller who enriched our knowledge of the infinite variations of human psychology. After his pioneering work with “sleepy sickness” patients (who were in fact survivors of an early-20th-century pandemic), Sacks went on to study the connections between music and the brain, as well as disorders such as Tourette's syndrome, Parkinson's disease, and many other little-understood disorders that often count Sacks as one of their first chroniclers.
Sacks was well known as a writer of such best-selling case histories as Hallucinations, The Man Who Mistook His Wife for a Hat, An Anthropologist on Mars, and his memoir of his early work, Awakenings, all of which have breathed new life into the dusty 19th-century tradition of the clinical anecdote. Sacks' writing, compassion and wide-ranging knowledge catapults the genre into the 21st century and brings the far frontiers of neurological experience into the view of millions of readers worldwide. Sacks died at age 82 in August 2015.
Read TED's long, wonderful Q&A with Oliver Sacks >>
Oliver Sacks | Speaker | TED.com