BBC Horizon 2008 - Total Isolation

점점 힘들어지는데..

생각보다 힘들어..
버틸수 있을지 모르겠네

정말 무서웠다

논란이 될만한 이 실험은
6명의 정상인을 대상으로

모든 감각을 차단했을 때
뇌가 받는 영향을 알아봅니다

세상에, 이제 헛것이 보여

이것은 과학의
오랜 의문이었으며

관타나모 수용소, 대량 인질 사태,
늘어나는 독방 감금 등에 따라

어느때보다 더 중요해졌습니다

공포감이 코앞까지 밀려옵니다

사실상 미치는거지요

인간 정신의 심연을 파고들어

완전한 고립상태의 인간이
어떤일을 겪는지 조사합니다

머릿속이 꽉 막혀서..

갈수록 죄어드는거 같아요

완전 격리 실험
(2008.1.22 BBC Two)

과거 40년동안은 감히
시도하지 못했던 이 실험에

가족, 친구, 직장을 잠시 뒤로한
여섯 사람이 참여합니다

정신을 완전히 잃고
어쩔줄 모르게 되지 않을까요

방안을 서성거리면서
나가지도 못하고

꼬박 이틀 갇힌채 절망하는
내모습이 상상됩니다

처음엔 별 걱정이 없었는데

실험날짜가 다가오니
불안함에 약간 동요됩니다

예상하기 힘든데요

잘 모르겠어요
48시간의 어둠밖에 없겠죠

폐기된 핵방공호에
연구에 필요한 시설을 갖추고

자극을 차단했을때
뇌가 받는 영향을 연구합니다

실험의 책임자
이언 로빈스 교수는

관타나모에 억류되었다 풀려난
영국인들을 다룬 경험이 있습니다

감금, 고문 피해자의 처치에 관한
영국 최고의 전문가입니다

보안상의 이유로
얼굴은 공개하지 않습니다

감각 차단의 영향에 관한 연구는
매우 중요합니다

감각 차단을 통해 굴복시키거나
자백을 받아내려는 시도가

전세계 도처에서
행해지고 있습니다

뇌에 주어지는 자극은
뇌세포간의 연결을 촉진하여

정보처리속도를 높이는것으로
알려져 있습니다

그러나 감각 자극을 줄였을때
어떤 영향이 있는지는

아직 연구가 부족합니다

정보처리능력이 실제로 줄어드는가,
이것은 흥미로운 주제입니다

48시간동안, 피실험자들은
홀로 남겨질뿐만 아니라

모든 종류의 자극으로부터
최대한 차단될 것입니다

몇몇 피실험자는
칠흑같은 어둠속에서

아무것도 보거나
들을수 없습니다

일부 피실험자는
더욱 심한 제약을 받습니다

촉각을 차단하고
시각도 제한합니다

그리고 단조롭게 지속되는
화이트노이즈만 듣게 됩니다

심리학자 팀 그레이너 박사도
피실험자들을 관찰할 것입니다

- 이곳이 방공호합니다
- 와우

실험에 앞서 모두들
마음의 준비가 되셨습니까?

물론이죠

이 방면의 연구가 시작된 계기는

극도의 감각 차단이 행해진
55년전으로 거슬러갑니다

한국에서 아빠가 뭘 하셨나고
아들이 물으면

폭탄을 퍼붓고 죽이고 부수러 갔다
이렇게 말할수 있겠어요?

1950년대 한국전쟁에서
미국/캐나다 포로의 상당수가

감각이 차단된채 감금되어
세뇌된 것으로 밝혀졌습니다

가족들 낯을 어떻게 보겠어요?

내가 비인도적 범죄자란걸
어떻게 말할수 있겠냐구요

이것을 이해하려고 북미 심리학자들은
극단적인 심리실험을 구상했습니다

외부 자극을 차단하고
그 영향을 조사한 것입니다

이 실험을 행한 도널드 헵은
결과에 충격을 받았습니다

감각 차단은 결국 극도의
지루함 속에 가두는 것입니다

갈수록 고통스러워지는
끔찍한 경험입니다

피실험자들은 잔인한
실험이라고 말했습니다

지루함의 정도가
인내심의 한계를 넘어..

어떤 피실험자의 표현을 빌면

히틀러도 그보다 더하진
않았을거라 하더군요

과학자들은 인간의 뇌가
정상 작동하려면

지속적인 외부자극이
필요하다는걸 알아냈습니다

그러나, 실험이 지나치게
비인도적이어서 중지되었습니다

그 후 40년간 과학은
많은 발전을 이루었습니다

뇌에 관한 이해의 폭은
크게 늘어났습니다

헵의 실험때만 해도
아는것이 적었습니다

뇌를 살펴보려면
직접 째는 수밖에 없었죠

이제는 CAT, MRI, PET 같은
장치의 도움으로

뇌에서 일어나는 일을
관찰할 수 있으며

뇌의 각 부분의 기능도
이해할 수 있습니다

건강한 정상인들을 대상으로
이제 이 실험을 재현합니다

모순된 느낌입니다

아주 안전하면서도
아주 위험한 느낌..

안녕하세요~!

아담입니다. 아 일단
저는 고양이를 네마리 키우는데
이중에 고양이 키우시는분?

아담은 스탠드업 코미디언입니다

고양이털이 날려서 짜증난다?

그럼 고양이를 셀로판 테이프로
둘둘 말아버려요

내 농담에 웃는 사람들로
가득찬 왁자지껄한 공간

그 안에 있는 기분은 최고죠
섹스보다도 좋습니다

제가 섹스를 못한다는
얘기가 되나요?

계속해서 자극을 끌어내는 그에게
어두운 고독은 두려움입니다

생각해보면
오싹한 일이예요

미쳐버리지 않을까나?
완전히 돌아버린다는건 아니지만요

정신이 나가서
난폭해지거나 한다면?

이전에는
이 실험이 기다려졌는데

아침부터는 약간 불안하네요

클레어는
심리학 박사과정에 있습니다

도전을 좋아하죠

저는 육체적으로 용감한
사람은 아닙니다만

도를 넘지 않는 선에서
자신을 시험해 보고 싶습니다

그래서 이런 도전을 즐기죠

초조하고 약간 걱정도 되고..

솔직히 매는 빨리 맞는게 좋겠죠

미키는 집배원입니다

100마일 울트라 마라톤이
그의 취미입니다

육체적인 것보다
정신적인 영향이 클겁니다

그는 격리 실험을 일종의
인내력 테스트로 생각합니다

정말 지쳐서
주저앉아 쉬고 싶을 때

긍정적인 생각을 떠올리며
버텨야 합니다

"할수 있어, 완주할수 있어"
스스로 되뇌입니다

48시간동안 뇌기능이
어떻게 저하되는지

정확히 파악하는 것이
실험의 핵심입니다

간단한 과제를 수행하는
능력을 측정하여

피실험자의 뇌기능 저하
정도를 측정합니다

격리 전과 후를 비교할 것입니다

이것은 시각기억능력 테스트입니다

이 그림을 똑같이
베껴 그려주시겠습니까

- 지금요?
- 네, 지금요

30분 뒤, 기억에 의존하여
아까 그림을 다시 그리게 합니다

해보실까요

복잡한 그림을 베끼면서
모양을 인식하고 기억했다가

다시 끄집어내는 능력을
측정합니다

기억력이 잘 기능하는지
보는것이죠

여기 네모가 있었고..

현재, 그림을 재생해내는
참가자들의 능력은 좋습니다

죽 따라 내려가면서
단어들을 읽으시는데..

이번엔 정보처리 테스트입니다

파랑, 검정, ..

피실험자는 단어를
글자대로 읽지 않고

단어의 색깔을 말해야 합니다

빨강, 녹색, 검정, ..

두뇌가 서로 상충되는 정보를
잘 처리하는지 보는것입니다

빨강, 검정, 파랑, ..

잘하셨어요

현재 참가자들의
뇌기능은 정상입니다

- 제가 잘 했습니까?
- 네, 그러신데요

기억, 집중, 정보처리 능력
모두 좋습니다

그러나 이틀간 자극을 끊으면
어떻게 될까요?

- 실험이 행해질 방입니다
- 네

어유, 휑하네

기분이 어떠세요?

긴장됩니다

- 흥분도 되고..
- 그러시군요

여기 카메라 둘, 마이크 셋, ..

계속 관찰할수 있게
적외선 카메라가 있습니다

기분이 어떠신가요?

꽤나 우울한데요

글쎄 뭐랄까..
딱 교도소 느낌인데

여기서 48시간이라..

미키씨, 이제 불을 끄지요.
이따 뵙겠습니다

감사합니다, 이따 뵙죠

잘해봅시다, 고마워요

- 나갈때 문 닫아주세요
- 알겠습니다

좋아요, 그럼 이만..

불과 몇초 후,
클레어는 무서워졌는지

불을 다시 켭니다

언제 다시 오실건가요?

내키시지 않으면
진행하지 않겠습니다

원하면 불을 켜셔도 됩니다

- 문 잠그실거예요?
- 아니요

잠그는거랑 아닌거랑
차이가 큰데요..

절대 안전하답니다

계속 진행해도
괜찮으시겠어요?

- 네 그래요
- 좋습니다

아 진짜 꿀꿀하네

아무것도 안보이고

완전히 깜깜해서
손을 들어도 안보이네

뭔가 들을만한 거리라도 만들려고

중얼거리는 중이예요

47시간 반 후에 어떤 기분일지
상상하기도 싫어진다

뭐 별일 없겠지..

자극의 부재가 벌써부터
마음을 어지럽히는 모양입니다

그리고 좀 춥고요..

이불이 젖은 것 같아요

클레어씨의 경우, 실험 시작부터
아주 초조해 했습니다

실험이 시작되고 나서
완전한 어둠속에 있다보니

자신의 감각 판단력에 대한
확신이 전혀 없는 상태입니다

저기요..

클레어의 이불을 확인해보니

약간 차갑기는 해도
젖어있지 않았습니다

문제 있으신가요?

이불이 젖었다고 했는데
별로 신경을 안써주시네요

젖은 이불속에서
잘 수는 없잖아요

참가자들이 격리된지
아직 얼마 안 지났습니다

전세계의 수많은 수감자들이

아주 오랜 시간동안
독방 신세를 지고 있습니다

미국에만 2만명이나 됩니다

62세인 패리스 캐리저는
살인 유죄 판결을 받고

100년 징역 및 사형을
선고 받았습니다

저는..

일반 독방을 들락거리며
몇년을 보냈습니다

가로세로 대략 2~3미터씩
되는 방에서

깜깜한 어둠속에 가둬집니다

한번에 10~15일 정도씩
그렇게 있었죠

법적으로 15일 이상 연속
감금은 불가능하고

적어도 4일간 밖에 내줘야
다시 독방에 넣을 수 있습니다

패리스는 적응하는 방법을
곧 터득하였습니다

상상의 세계에 빠져들어
고통을 잊으려는거죠

나중에 알게 된것이지만

자제하지 못하면
스스로를 망치게 되기도 합니다

강아지, 말, 자유의 기분,
시냇물 소리, ..

이런것들을 상상하죠

이런 이미지들을
머릿속에서 가지고 놉니다

정신이 들고 나면,
다리를 꼰 채로 바닥에서

벌벌 떨고 있는 자신을
발견하곤 했습니다

무릎이며 발목이며
생채기가 생긴줄도 모르고

그러고 있었습니다

많은 심리학자들은
독방 감금에 의한 감각 차단이

'중앙수뇌부'라는 뇌의 핵심기능에
영향을 끼친다고 믿습니다

이것이 뇌의 특정 영역이
담당하는 기능인지는 아직 모르지만

언어, 기억, 시각 능력 등의
정신작용이 여기에 해당됩니다

외부세계를 이해하고 소통하는데
필수적인 부분입니다

중앙수뇌부가
48시간의 감각 차단에

어떤 영향을 받는지도
이 실험의 주제입니다

참가자 중 두번째 그룹은

앞의 3명보다 더 혹독한
조건에 놓일 것입니다

주디는 장난감 회사의
카피라이터입니다

아주 들뜬 기분이예요

바니는 영상기록
관리전문가입니다

어색하고, 낯설고,
두려운 기분입니다

빌은 전직
광고회사 임원입니다

갈수록 초조해지기 시작합니다

사람을 위축시키는
그런 분위기군요

그는 명상의 힘에 의지하여
대처할 생각입니다

저는 매일 혼자만의
시간을 갖습니다

아침 일찍 일어나
혼자 보내는 시간이 좋아요

꼭 필요한 경우가 아니면
세상에 모습을 드러내지 않는

은둔생활에 대한
환상도 갖고 있습니다

물론 두뇌가 받는 영향을 측정할

테스트를 진행해야 합니다

이틀 뒤에 똑같은 실험을
반복할 것입니다

주어진 알파벳으로 시작하는
단어를 최대한 많이 말해보세요

언어 유창성 테스트입니다
기억력, 언어능력이 필요하죠

F로 해볼까요

- Fake
- 좋아요

Fig

Fart

이번엔 중앙수뇌부가 다른 범주로
전환하는 능력을 측정합니다

이제 1분 내에 동물의 이름을
최대한 많이 말해보세요

쥐, 햄스터

토끼

표범, 퓨마

잘하고 있는 것 같군요
48시간 뒤에는 어떨까요?

이번에는 피암시성 테스트입니다

이제 짧은 이야기를
읽어드릴텐데요..

새로 받아들인 정보를
이미 기억하는 내용과 대조하는

중앙수뇌부의 능력을
측정하는 것입니다

남크로이든의 안나 톰슨씨는
휴가차 스페인에 갔는데..

호텔 밖에서 핸드백을
도둑맞았습니다. 그안에는..

기억과 다른 내용을 들었을 때,
그것을 쉽게 받아들이고

자신의 기억이 잘못되었다며
마음을 바꾸는지 테스트합니다

30분 뒤, 아까 기억한 내용을
어지럽히는 질문을 던집니다

강도는 흑인이었습니까,
아니면 백인이었습니까?

실험자가 주는 암시에 의해
기억한 내용을 번복하게 될까요?

이상하네, 동양인이라고
하지 않았나요

강도를 주먹으로 때렸을까요,
핸드백으로 때렸을까요?

아뇨, 발로 찼다고 했는데

아니예요

외부의 암시에
적절하게 저항하고 있군요

48시간 뒤에는
이 능력이 무너질까요?

이들은 감각 차단을 위한
장비를 착용합니다

고글.. 잘 안보이시죠
편안하십니까?

- 네
- 좋아요

폐소공포증에 시달리겠는데요

막연하게 희미한
모양밖에 안보입니다

정말 묘한 느낌인데요

얼마나 버틸지 몰라도
하는데까지 해봐야죠

마지막으로 화이트노이즈를
켠 다음 격리됩니다

한시간 뒤
주디는 잠을 청합니다

곧이어 바니도..

첫번째 팀도 마찬가지군요

깨어있는건 빌 뿐입니다

원래 계획대로
명상에 잠기는군요

만트라 명상을 하기에
딱 좋은 조건인걸요

아주 편안하고 행복합니다

헤드폰에서 나는
화이트노이즈가

열대 폭포수 소리 같습니다

빌은 꽤 오랫동안 깨어 있는 반면

다른이들은 한시간 반 안에
모두 잠들었습니다

흥미롭게도 빌은..

향성 검사에서 유일하게
내향성이 높았던 참가자입니다

반면 다른이들은 모두
외향성 지수가 높았어요

감각 차단에 대처하는 방법으로
모두가 잠을 택한 셈입니다

이제 실험 9시간 경과.
어둠이 짙어갑니다

피실험자들은 아무것도 없는
기나긴 시간에 직면합니다

까라지는거 같아요..

지루해 미치겠어요..

오전 2:35
일어났네요. 지금이 아침이면
하루종일 이상태로..

젠장..

어떻게 참아..

둘째날의 동이 터 옵니다

방공호에서
18시간을 보냈습니다

연구의 일환으로, 피실험자들이
시계나 햇빛 없이

시간 관념을 얼마나 오래
유지하는지 관찰합니다

몇몇은 벌써부터 어리둥절한
상태가 된듯 합니다

아 기분 이상하네

중간에 한번 깨서
얼마나 잤는지도 모르겠고..

몇시일지 맞춰보죠

오전 10:25
감도 못잡겠는데..
아침 6시쯤?

아니면 오후 1시?

얼마나 지났는지 모르겠군요

전혀 모르겠어요

시간을 가늠할 방법이 없네요

햇빛이나 시계가
그래서 필요하지..

대학강사 브라이언 키넌은

베이루트에서 인질이 되어
창문 없는 감방에 갇혔을때

햇빛을 받지 못하여
큰 어려움을 겪었습니다

7~8달을 암흑속에서 보냈죠
정확한 기간은 모릅니다

햇빛이 전혀 없었습니다
잠도 끊어 잤죠

8시간씩 이렇게가 아니라
노루잠만 계속 잤습니다

몇분 자다 일어나서
몇시간 깨어있고 이런식으로

불규칙한 패턴이었습니다

수면 뿐만 아니라
깨어있는 시간도 고통이었습니다

아무것도 없는 상황은
극도로 견디기 힘듭니다

머릿속에선
'다음 10분은 또 어떻게 보내지?'

'아니 몇달 뒤는?
당장 내일이 오기는 할까?'

이런 의문만이 가득합니다

계속된 감각 차단이 마침내
정신을 쏙 빼놓습니다

실감하는건 오직 어둠뿐입니다
아무것도 믿을수가 없어요

주위에 사람이 있긴 한지,
내가 제 정신인지조차..

한번은 자다 일어나서는

얼굴을 꼬집으며
자문했습니다

'내가 살아있기는 한걸까?
살아있는지 어떻게 알지?'

24시간 후, 몇몇은
동요하기 시작합니다

이제.. 점점.. 더 우울해..

빛을 못보니 아주 죽겄네

난 모르모트야..!

다른쪽 팀은 그 나름의
어려움을 겪습니다

감각을 차단하려고
팔에 씌운 토시가

오히려 고통스럽게만 하여
이것을 풀기로 합니다

머리가 무뎌지는 것은
분명해 보입니다

창의적인 생각을 하기가
약간 힘들군요

깜깜한 상태에서
머리를 굴리긴 어려워요

그냥 정신이 멍해요

머리가..
에이 모르겠다

그저 아무것도 하기 싫어요

아직 정확히는 알수없으나,
분명한 것은

뇌세포들이 잘 연결되어야
정보 처리가 원활해지는데

자극이 거세된 상황에서는
이 연결이 줄어든다는 것입니다

반대의 경우,
즉 뇌를 자극시키면

뇌세포 연결이 증가한다는건
잘알려진 분명한 사실입니다

조금전부터 맘이 불안합니다

여길 벗어나고 싶어요

다른 뭐라도 좀 했으면..

슬슬 신경질이 납니다

과히 좋지않은 기분이예요

내가 무슨 손발 묶인
실험쥐가 된거 같고..

당초 예상한것보다
버거운 모양입니다

시간이 갈수록 더욱
지루하고 힘겨워지는데

마땅히 해소할 수단이
없는 상황이니까요

조그만 잠수정을 타고
해저로 내려가는 기분입니다

수압의 압박..

비유하자면 그러네요

30시간이 경과했습니다

주디는 내내
잠만 자는듯 합니다

다른 방에서는
긴장이 고조되고 있습니다

콩알만한 자유라도
없는것보단 낫지

피실험자들은 계속
방 안을 서성이는군요

감금 상태에서
이리저리 걸어다니는 것은

동물과 인간에 공통으로
나타나는 현상입니다

머리를 안쓰고도 할수있는
행동이기 때문이겠죠

운동도 되지만, 자극이 없는
상황을 타개하려고

스스로 움직여서
자극을 만들어내려는 겁니다

얼마나 할일이 없으면
이리저리 걸어다녔겠어요

'걸음수를 잘못 세서
부딪치지 않을까..'

이런 스릴밖에 없는 일이
뭐가 재밌겠어요

거의 돌아버릴거 같아요

윽!

패리스 캐리저도 독방에서
똑같은 습관에 시달렸습니다

걷고.. 또 빨리 걷고..

하루 18시간, 22시간씩이나..

세걸음 앞으로, 세걸음 뒤로,
다시 돌고, ..

아파서 못견딜 때까지
그렇게 했습니다

18년의 수감 생활 후에야
진범이 밝혀지면서

그는 누명을 벗었습니다

그러나 격리 수용의 영향은
아직도 그를 따라다닙니다

독방 생활의 대가를
최근에야 깨달았습니다

저는 시간 관념을
상실했습니다

내가 이걸 했었나 안했었나
이런건 기억을 해도

어떤 순서로 했는지는
오락가락합니다

간단한 지시를
따라하는것도 어렵습니다

시시각각 끼어드는 것들을
처리해야 하는

그런 종류의 일은
할 수가 없습니다

번화가에서는 운전도 못하죠

말하자면 제생각에는..

제 원래 능력의 3분의2는
잃어버린듯 합니다

나온지 10년이 지났지만
아직도 그대로예요

영구적인 손상을
입은거라 생각합니다

참가자들이 방공호에 들어간지
40시간이 지났습니다

바니는 무료함을 이길
방법을 찾았군요

주디는 여전히 꿈속입니다

그러나 다른 방에선
얘기가 다릅니다

아담은 한시간 반 전부터
매우 조용합니다

눈만 뜨면 쉴새없이
말을 하거나 뭔가를 하던

이전과는 다른
아주 특이한 상태입니다

울고 있는게 아닌가
싶을 정도인데요

그만두겠다고 하지는 않을까
하는 생각도 듭니다

계속 버텨야 하나
그만둬야 하나

고민하면서
괴로워하는지도 모르죠

머릿속이 완전 먹통이야

편안하고 풀어진 마음을
유지하는 것이

시간이 갈수록
힘들어지고 있습니다

24시간 더 있으면
한계까지 몰고 가게 되죠

오랜 시간이 지나자
더욱 특이한 현상이 나타납니다

세상에, 이제 헛것이 보여

굴 쌓아놓은 더미가 보여

굴이 한 5천개쯤 쌓여있는게..

와 세상에..

빈껍데기들인데 먹음직스런
진수성찬을 보는것 같아

만져봐야지

사라졌네

다시 보인다

듣고 있어요?
나 헛것이 보인다구요

뱀 한마리가 보여요

이렇게 가고 있네..

움직이는 형체들이 보였어요
자동차, 얼룩말, .. 멋지던데요

약간 무서웠던건,
있지도 않은 형체들이

마치 거기 있는것 같은
착각이 들었다는게

그게 무서웠어요

좀 이상하네

모든게 으스스하고 무서워

내 방이 갑자기 날아오르는
듯한 이상한 착각..

전투기들이 휙휙 날아다니고
모기떼들이 윙윙거리고..

주의를 기울일 대상이
전혀 없으니 환각이 생깁니다

받아들이는 정보가
없는 상황에서도

두뇌는 끊임없이
정보처리 활동을 하려합니다

이를 위해 자체적으로
정보를 가공해내는 거죠

키넌은 수개월의 감금중에
끔찍한 환각을 겪었습니다

소름끼칠만큼 뚜렷하게
기억이 납니다

사막에 홀로 버려져서

쪄죽을 정도로 덥다가..

갑자기 한순간

얼어붙을 정도로 추워지는..

사막의 바람이 내몸의
살덩이를 뜯어내는..

그 느낌이 생생합니다

앙상한 뼈다귀만 남은채로
덜덜 떨었죠

환각은 눈에 보이는것만으로
그치지 않았습니다

음악이 들렸습니다

감방 밖에서 들려왔습니다

아니란건 알죠
하지만 들렸습니다

온갖 종류의 악기가
내는 소리들..

백파이프, 아프리카북,
치터, 플라멩고 기타, ..

신기한 경험이죠

그러고 몇분이 지나도
사라지지 않는겁니다

정말 무서웠습니다

그러다가 템포가 빨라지고
소리가 점점 커지더니

첼로, 피아노, 오케스트라, ..
더 많은 악기 소리가 들리고

소리는 더욱 커져갔습니다

나는 너무나 무서워서

환청을 쫓아내려고
당장 머리를 벽에 받았죠

이렇게 주의를 돌리려고 해도
생각대로 안됩니다

거기에 중독된다고
어떤 위로가 되는것도 아닌데

음악은 무지하게 오래
지속되었습니다

누가 나에게 총을 겨눴다 해도
더 무섭진 않았을겁니다

키넌은 4년후에 풀려났습니다

그의 정신을 회복시키는데
몇달이 걸렸고

그의 인생을 되살리는데는
몇년이나 걸렸습니다

47시간째, 놀랍게도
모든 참가자가 버티고 있군요

조금전부터 기분이 무겁고
압박이 심합니다

아무 생각도 안나..

그저..

그냥 멍해..

말하기도 싫어요

긴 기다림이
마침내 끝났습니다

클레어씨,
이언입니다

48시간이 경과했으니
모시러 가겠습니다

네, 고마워요

접니다..

간 떨어지는줄 알았네,
안녕하세요

죄송합니다

48시간 실험이
모두 종료되었습니다

아싸~!

이야~호!!

날아갈듯한 이 기분
아무도 모를거야~

- 기쁘시죠?
- 뽀뽀라도 해줄게요!

주디씨,

와~ 좋아 좋아

몇몇 참가자들에겐
악몽같은 48시간이었습니다

이제 과학자들이

지적 능력의 저하 정도를
검사할 차례입니다

이전의 테스트를
되풀이합니다

시각기억능력 테스트.

아까 그리셨던 것을

기억해서 다시
그려주시겠습니까

미키는 대단히 힘들어합니다

기억 능력이
36% 감소했습니다

다른 피실험자들도
기억력이 감퇴하였습니다

고차원 능력을 관장하는

중앙수뇌부가 받은 영향은
더욱 두드러집니다

글자 말고 색깔 말이죠?

정보처리 테스트에서는
모든 참가자들이

글자를 읽지 않고
색깔을 말하는데 있어

어려움을 겪었습니다

파랑, 검정!

아담이 특히 어려워합니다

훨씬 어렵네요

끝까지 읽는데 걸린 시간이
69% 늘어났으며

실수는 6배나 많았습니다

빨강, 검정!

아.. 괴로워요~

거의 끝내셨습니다

녹색, 검정, ..

검정, 빨강, ..

진짜 어려운데요

아담씨는 정보처리 테스트를
특히 못했습니다

단순한 개인차일
가능성도 있지만

아담이 매우 외향적인
사람이라는데 주목합니다

외향적인 사람은 꾸준히
정보를 주고 받는데 익숙합니다

외부 정보가 단절되었을때
더 큰 영향을 받았을수 있죠

알파벳 한 글자를 불러드리면

주어진 알파벳으로 시작하는
단어를 최대한 많이 말해보세요

F로 해볼까요

Fertiliser

빌은 언어 유창성 테스트에서
힘겨워하는군요

기억력과 어휘력을 조합해
범주를 만드는 능력이

48시간만에 심각하게
손상되었습니다

어이구~

다른 참가자들도
대체로 비슷합니다

좋습니다

7월의 어느 화요일 아침
부부가 출근을 했는데, ..

과학적으로 가장 중요한 초점은
피암시성 테스트입니다

안나와 존이 소년을 쫓아가서
존이 자전거를 멈춰세웠습니다. ..

피실험자들은 감각 차단 후에
외부 암시에 쉽게 굴복할까요?

간단한 질문을 드려도
괜찮으시겠죠?

언덕을 올라오는 밴을 보고
소년이 겁을 먹었습니까?

(O)
밴이나 언덕 얘기는
못들은것 같은데요

언덕을 올라오는 밴을 보고
소년이 겁을 먹었습니까?

(X)
네

존이 소년의 팔을 잡았나요,
어깨를 잡았나요?

(O)
자전거를 잡았을걸요

존이 소년의 팔을 잡았나요,
어깨를 잡았나요?

(X)
팔이요

남성 참가자 일부에서
피암시성이 증가했습니다

언덕을 올라오는 밴을 보고
소년이 겁을 먹었습니까?

(X)
네

여성 참가자들의 피암시성은
전혀 증가하지 않았습니다

반면 남성들은 피암시성이
상당히 증가했습니다

감각 차단 같은 형태의
스트레스를 받았을 때

이 남성 참가자들의 경우
자신의 기억이나 믿음을 버리고

타인의 관점을
쉽게 받아들였습니다

이번 실험 참가자들의
결과만으로 판단하는것은

섣부른 결론일 수 있습니다

감각 차단에 의한 피암시성 증가는
의미심장합니다

세계 각지에 이런 환경에
처해 있는 사람들이 많은데

이렇게 얻은 정보의 신뢰성은
낮다는 것을 의미합니다

심문자가 주입하려는 생각을
쉽게 받아들이기 때문이죠

결론적으로, 격리 상태에서
중앙수뇌부가 받는 심대한 영향이

이번 실험에 의해
처음으로 입증되었습니다

정보처리 속도,

추상화 능력, 언어 유창성
등은 감소했고

피암시성은 증가하였습니다

종합해보면, 중앙수뇌부의 기능이
저하된 것입니다

이틀간의 지하생활 후
마침내 해방입니다

밖에 나오니까 어떠세요?

진짜 끝내줍니다

모든게 새롭게 보이네요

햇빛..

날씨도 좋구요
정말 정말 멋져요

- 밖에 나오니까 어떠세요?
- 믿기지가 않아요

핵방공호가
이렇게 아름다울줄이야

정말 기가 막힌데요
꽃 하며..

여기 처음 왔을땐
볼품없어 보였는데..

새소리, 구름, 녹음,
화려한 식물들, ..

햇빛을 못보고 살기엔
이틀은 참으로 긴 시간이죠?

태어나서 처음이구요

와 끝내준다~

자원참가자 분들은 48시간
감각 차단을 경험했습니다

물론 인도적인 환경에서요

이정도 시간에도
정신 능력이 영향을 받았다면

몇달, 몇년 감금생활을 하는
사람들은 어떻게 될지

예측할 수 있는
좋은 자료를 얻었습니다

40년만에 치러진
감각 차단 실험을 통하여

인간의 정신이 얼마나
부서지기 쉬운것인지 보았습니다

완전하게 홀로 고립되는
것만으로도 말입니다

영어자막 수정, 번역, 한국어자막
DC 과학갤/다큐갤 '디핑'
croydon.egloos.com

Oh, it's getting tough now.

This is harder than I thought.
I don't know if I can do this.

In this controversial test,
six ordinary people are deprived

of all sensory stimulation to
discover the impact on their brains.

Oh, God. I'm hallucinating now.
Tim, I'm hallucinating.

Science has struggled for many
years to investigate this question

but now, in the era of Guantanamo
Bay, mass hostage taking

and the increasing
use of solitary confinement,
it's more important than ever.

You could smell the fear and you
could smell it from 15 or 20 feet.

They decided to go insane,
clinically insane.

This research delves
deep into the human mind

and finds out what happens
when you are left truly alone.

The walls are starting to close in,

the walls of my mind
are starting to close in.

Six people will leave their homes,
jobs and friends
to take part in research

which for the past 40 years has
been too controversial to undertake.

My fear is that I will start to
lose my mind having nothing to do.

I can see meself
pacing round the room and

getting frustrated that I can't
actually go anywhere, that I've got
to stay in one place for 48 hours.

Initially I wasn't that concerned,
but as the date approaches

I find I'm feeling
little ripples of trepidation.

I've no idea how I'll be.

I've no idea. Maybe 48 hours
in the dark's just what I need.

This disused nuclear bunker is
the setting for a piece of research

which is designed to study
what happens to the brain
when it's deprived of stimulation.

In charge is Professor Ian Robins,
the man who treated some of

the British Guantanamo detainees
when they were released.

He's one of the country's leading
experts in treating the victims of
solitary confinement and torture.

We cannot feature his face
for security reasons.

I think it's very important that
we're looking at the impact of
sensory deprivation,

particularly when we think of the
number of places around the world

for instance where sensory deprivation
is being used as a weapon and being
used as an aid to interrogation.

We know that stimulation helps to
increase connections within the brain

that speed the flow
of information around the brain,

but there have been relatively
few studies of the impact of a
reduction in sensory stimulation.

So it's quite a useful thing to see

whether you get a reduction
in that ability
to process information effectively.

For 48 hours our subjects
will not just be left alone.

Every effort will be made
to starve their senses of
any kind of stimulation.

For hour after hour
some will lie in pitch-black rooms,

unable to see or hear anything.

Others will endure even
greater deprivations.

They will have their sense of touch
cut off, their eyesight
severely impaired,

and all they will hear
is the endless drone of white noise.

During the test the subjects will
also be observed by psychologist
Dr Tim Grainer.

Come on, then, this is the bunker.
Oh, wow. Oh, wow.

Does everybody feel prepared and OK
at the beginning of the experiment?

Yes. Definitely.

55 years ago it was sensory
deprivation of the most extreme kind

which led to
the first experiments in this area.

When my son asks me
what I did in Korea, how can I
tell him that I came over here and

dropped bombs on people, destroying
and bringing death and destruction?

In the 1950s, at the height
of the Korean War, thousands of
American and Canadian POWs,

who had been held in
conditions of sensory deprivation,
appeared to have been brainwashed.

How can I go back and face my family?

How can
I tell them these things, that I am
a criminal in the eyes of humanity?

To understand more, North America's
leading psychologists designed a
series of extreme experiments

to cut off people's senses
and find out how
the isolation affected their minds.

The scientist in charge,
Professor Donald Hebb,
was surprised by the results.

Sensory deprivation really is
a way of producing extreme monotony.

It's apparently a horrible
experience, getting worse and worse.

Some of our subjects
talked about cruelty.

What they said was that the degree of
boredom became intolerable and was,

one subject said, as bad as anything
that Hitler had ever done
to any of his sub...

to his...victims.

The scientists had discovered
that the human brain

needed constant stimulation for
its healthy functioning.

However, the experiments
were considered too cruel
and were closed down.

But since then there have been
40 years of scientific advance.

Our knowledge of the brain
has moved on enormously.

During Hebb's period
we knew very little about what was
going on inside the brain.

The only way you could
visualise the brain itself
involved very invasive processes.

Now we have things like CAT scans,
MRI scans, PET scans.

They allow us to know a lot more
about what's going on
inside the brain

and about
the functional relationship between
different parts of the brain.

Now, once again,
normal, healthy people will be
subjected to sensory deprivation.

I feel it's a bit of a paradox.
I feel very safe and very
insecure at the same time.

Hello! Hello.

I'm Adam. Just before I start,
I've got four cats. Any of you
got cats at home?

Adam is a stand-up comedian.

If you're sick of being covered
in cat hair, get some Sellotape

and wrap it round your cat.

The buzz of having a packed room
roaring at everything

you're saying for an hour solid
is, I suppose, the best feeling...

It's better than sex, which just
probably shows how bad I am at sex.

He leads a life of constant
stimulation and fears the solitude
of the dark room.

'When I think about this,
I'm terrified.'

'I think people could go mad.
I don't mean mad, mad permanently,
but just, you know...'

If I get to a stage where
I'm freaking out, what if I
start smashing things up?

Beforehand I was quite
looking forward to it

and as the morning's going on I'm
feeling slightly more apprehensive.

Clare is studying
for a psychology PhD.

She likes a challenge.

I'm not physically courageous at all,
so I guess in that sense I do like to

challenge myself, because
that's a limitation which
otherwise you've got to live with.

So I do try and push myself
on things like that.

Nervous, a little bit worried.

To be honest, I want to get it
started and get in there.

Mickey is a postman.

His favourite hobby is
running 100-mile ultra-marathons.

It's mind blowing.
It's not just the physical
thing, it's the mental thing.

He plans to treat the isolation
like an endurance test.

There's times where you're so low
you want to sit down and cry.

You've just got to think about
the positive things in life.

You've just got to say to yourself,
"Yeah, I can do it. I'm going to get
there. I'm going to finish it."

At the heart of the research, the
psychologists want to investigate

precisely how the brain will be
disrupted over the 48-hour period.

They will conduct a series of tests
which will measure any deterioration

in the subject's ability to
perform the simplest of tasks.

They'll be tested before they go in
and when they come out.

This is the visual memory test.

Could you copy this design
onto here for me, please?

Now?
Right now.

30 minutes later they're
asked to recall the design
and re-draw it from memory.

Off you go.

Drawing test, we're looking at
people's ability to recognise and
learn from copying a very complex figure

and then be
able to recreate that from memory.

It's a test of how well their memory
is functioning.

This one should be a square.

At this stage they seem to be able
to remember and recreate
the original design well.

What I'd like you to do is read
these words out beginning up here
and going down this column.

And this is
the information processing test.

Blue, black...

In this test the subjects are asked
not to read the words as written

but to say the colour in which
they're printed.

Red, green, black.

It tests the brain's ability
to process two conflicting
pieces of information.

Red, black, blue.

Very good, OK.

At the moment the subjects' brains
seem to be in good shape.

Did I get it all right?
You did actually, yeah.

Their ability
to remember, concentrate
and process information is fine.

But what will they be like
after 48 hours in the dark room
deprived of all stimulation?

This is the room where
the experiment takes place.
OK.

Oh, wow! That's bleak.

So how are you feeling now?

Nervous.

Excited. Nervous and excited? OK.

In this room there are
two cameras, three microphones.

The cameras have infrared
so we can see at all times.

How are you feeling?

Quite depressed actually.

I don't know. There's something
very prison-like about it.

Yeah, 48 hours of this.

OK, Mickey, I'm going to turn the
light off. We'll see you later on.

OK, thanks. See you later.

Good luck, thank you.

Shut the door on your way out!
Will do.

All right, then. Bye.

But within seconds
Clare gets very anxious

and turns the lights back on.

God, this is weird.

I can't see a thing.

It's pitch black.
I can't see my hands.

I'm talking just cos, I suppose,

it's giving me something to hear.

I can't bear the thought of what
it's going to be like in
47 and half hours' time.

It's not going to happen.

Straightaway
the lack of stimulation is
having a disturbing effect.

Also, it's a little bit cold in here,

and I think my blanket is wet.

I think, with Clare, firstly she was
very anxious when she went into the
experiment

but, once in there, was finding it
difficult to decide

whether her sensory judgements
were accurate, because
she was in complete darkness

so it was
an extremely difficult thing to do.

Hello?

Clare's sheets were checked.

They were a little bit cold
but they were not wet.

'Hello, what's the problem?'
SHE GASPS

I don't think people are taking
my concerns very seriously
about the sheets being wet.

'Nobody should have to sleep
in wet sheets.'

The subjects have been
alone for only a short time.

Across the globe,
thousands of prisoners

are held in solitary confinement
for vastly longer periods.

In America alone, there
are 20,000 such inmates.

62-year-old Paris Carriger was
found guilty of murder and sentenced

by an Arizona court to 100 years
in prison and the death penalty.

I have spent

several years off and on
in a standard isolation cell.

What that means is that
this is a cell approximately
six feet by eight feet.

It is a place where
you're kept in the dark.

The times that you were
spending at that time were
10 to 15 days at a stretch.

By law they couldn't
leave you in more than 15 days

without taking you out for four
before they put you back in.

Paris soon developed
his own way of coping.

I went away in my head and I found a
place that I could deal with better.

And I only became aware

that this was self-destructive
when I couldn't stop going into it.

I would imagine dogs, horses
and the smell of freedom,

the sound of a brook.

And I would play this set of images
in my head

and sometimes I would wake up
and I would catch myself sitting

cross-legged on the floor
and rocking.

And I would have been sitting
there long enough to wear sores

on the back sides of my knees
and the bottoms of my ankles.

Many psychologists believe sensory
deprivation caused by various
kinds of solitary confinement

can affect a crucial function of the
brain called the central executive.

No-one knows if this is controlled
by a specific part of the brain

but it describes the mental
processes which coordinate functions
such as language, memory and vision.

It allows us to understand and
interact with the world around us.

One aim of this research will be
to find out how badly

the central executive is affected
by 48 hours without stimulation.

The second group of
subjects are about to endure

even harsher conditions
than those in the dark room.

Judy is a copywriter
for a toy manufacturer.

Quite excited to get started,
I think.

Barney is a film archivist.

Just sort of dislocation,
strangeness, fear.

Bill is a former ad executive.

I'm actually starting to feel
a little more nervous about
the whole experience.

This is a very...
rather intimidating place.

He thinks he's going to be able to
cope with the isolation well by
relying on the power of meditation.

Every day I like to
spend time on my own.

I like to get up early
and have those early morning hours
all to myself.

I've sometimes fantasised that I'd
like to be a hermit and maybe just
come out every couple of weeks and

buy a few supplies and
then go back to my cabin.

Once again the subjects have
to undergo a series of tests

to discover the effect of
sensory deprivation on
the central executive.

These will be repeated
at the end of the two days.

So I'll give you one letter and I
want you to list as many words as
possible that begin with that letter.

This is the verbal fluency test,
which requires them to use
memory and language.

OK, the first letter is F.

Fake. OK.

Fig.

Fart.

Then the central executive's
ability to switch to
a different category is tested.

Next I'd like you to list as many
animals as possible in one minute.

A rat, a hamster,

a rabbit.

A leopard, a puma.

They seem to be able to cope for now
but what will happen in 48 hours?

Then the suggestibility test.

So what I'm going to do is read out
a sort of short story to you.

This examines the central
executive's ability

to absorb new information
and check it against that
already stored in the memory.

Anna Thompson of South Croydon was
on holiday in Spain when she was held
up outside her hotel

and robbed
of her handbag, which contained...

The suggestibility test is looking
at the extent to which people start
to accept a different point of view

and to come to believe that they
have somehow made a mistake
and they've changed their view.

30 minutes later,
a series of misleading
questions are put to them.

Were the assailants black or white?

Will the subjects be influenced and
change their account of the story?

Gosh, you know,
I thought they were Oriental.

Did the woman hit one of the
assailants with her fist or handbag?

No, she kicked him.

No.

At the moment they seem able
to resist suggestion.

But will 48 hours of nothing
break them down?

They start to put on the devices
which will cut off their
sensory perception.

Here's the goggles, you can't
see much. Are they comfortable?

- Mm-hm.
- OK.

It's quite claustrophobic, isn't it?

I mean, you know, I can't see
anything but the vaguest of shapes.

Truly bizarre.

I don't know how long I'll last.
I'll just keep going.

Finally they're exposed to
white noise and left alone.

Within an hour,
Judy settles down to sleep.

Shortly followed by Barney.

And the same thing is
happening in the dark rooms.

Only Bill stays awake.

He sticks to his plan and meditates.

This is like a perfect
mantra meditation facility.

It immediately made me very peaceful
and blissful.

The headphones, which give
kind of this low white noise sound,

is sounding
very much like a tropical waterfall.

Bill's been awake for quite a bit.
It's really interesting because

the others all sort of
fell asleep, you know, within
an hour and a half of getting in,

whereas he's stayed awake.

What I think is incredible is
he is the only person who scored high
on the introversion scores.

Everybody else scored
high on the extroversion.

It's almost as though they've coped
with sensory deprivation by having
to fall asleep.

It's nine hours into the test,
and darkness falls.

Now the subjects have to face up to
the long hours of nothing.

I think this is a bit of a...

bit of a low.

I'm finding it grossly boring
at the moment.

Now I'm awake. If it is the morning
I'm now stuck here all day
and all night and all day

Oh, my God.

That's unbearable.

Dawn breaks on the second day.

18 hours have passed in the bunker.

As part of the research,
the scientists want to find out

how long it takes the subjects
to lose track of time in
the absence of watches or sunlight.

And as the morning progresses,
it's clear some of them are already
becoming disorientated.

Oh, this is weird, I've no idea
how long I've slept for now

because I've slept twice
in the night.

So let me have a little guess now
what time it is.

I can't really know, can I?

It could be six in the morning.

or it could be one in the afternoon.

I've no idea how far
through this experiment we are.

But I don't really.

There is no real gauge of time.

That's why we need the sun,
or a clock.

For university lecturer Brain Keenan
the lack of daylight had a profound
effect when he was taken hostage

in Beirut and held in
a windowless cellar.

I reckon I was in the dark about
seven or eight months, I can't be
sure. It was very hard to tell time.

There was no daylight at all
so I slept fitfully.

I didn't go to sleep and sleep for
the eight hours. I catnapped.

I slept for ten minutes, woke,
stayed awake for a couple of hours,

and went to sleep for an hour or
maybe three hours.

It was that kind of random pattern.

The darkness didn't just affect
his sleep. It deeply troubled
his waking hours as well.

The nothingness was extremely hard
because the question in your head is,

how am I going to get through
the next ten minutes?

Or, months later, how am I going to
get through the next day,
if there is another day?

Is there enough left in my head?

Until eventually the sensory
deprivation became all-consuming.

The blackness was palpable. There was
nothing there to confirm to me

that there was human existence
outside me or even in me.

I remember on one occasion waking up

and having to...

squeeze my face

and my chest and thinking
to myself,

"Am I still alive?
How do I know I'm alive?"

After just 24 hours in the dark room
some of the subjects are
having unsettling reactions.

It's quite...
it's getting quite...
it's getting quite depressing.

I'd kill for a tiny bit of light.

I'm the guinea pig.

In the other rooms
the subjects are having
their own particular difficulties.

Far from cutting off the stimuli,
the arm cuffs are causing rashes
and pain

so the psychologists
instruct that they be removed.

It's also becoming clear that their
brains are starting to slow down.

I'm finding creative thought a little
bit harder at the moment.

It's really hard to
stimulate your brain with no light.

It's blanking me.
It's not making me...

I can feel my brain just,

I don't know,

not wanting to do anything.

It's hard to know exactly what's
happening, but what we do know

is that the cells which connect
nerve cells together and speed up
the flow of information, dendrites,

may lose some of their connections
in the lack of stimulation.

We certainly know the converse is true,
that if you stimulate the brain

you increase the rate of dendritic growth
and the number of connections.

Just in the last sort of while
I've been feeling agitated.

I don't really want to be here.
HE LAUGHS

I'd rather be doing other things.

Things are starting to get on
my nerves, just the whole thing.

And I'm not feeling that great.

Kind of being observed like
some kind of helpless lab rat.

I think it's been more challenging
than he suspected.

As it's become increasingly sort
of boring and increasingly sort of
arduous, it's harder to cope

and he's finding there's
no other means that he can
access to sort of help him cope.

Well, it's like I'm in
a little submarine and

I'm getting closer and closer to
the bottom of the ocean

and so, like, the pressure...

That's the only analogy I can make.

It's 30 hours into the experiment.

Judy seems to be sleeping
through the whole experience

but in the other rooms
the pressure is building.

This is a bit of freedom.

That you try to deny me.

As the test progresses,
the subjects pace endlessly
back and forth across their rooms.

This behaviour of pacing up and down
is something we see in animals
as well as people

when they're kept in confinement.

I think it's something you can do
without needing to think about it,

in part attempting to exercise,
but I think it's simply a reaction
to the lack of any input,

and you provide the input
physically to yourself.

I wasn't enjoying it. I thought,

"I'm just doing this
because there's nothing else to do.
I'm walking back and forth."

What could be more monotonous than
walking back and forth in the dark,

where your only thrill is, am I
about to hit the wall by mistake
cos I've miscounted the steps?

Yeah, I did think,
this is close to insanity.

THUMP
Oh!

The same behaviour afflicted
Paris Carriger during the long
years in solitary confinement.

I walked, paced, at a very quick
pace...

..anywhere from 18 to 22 hours a day.

I would pace three steps forward,
three steps back,
and do that pivot, so that...

I would reach a point where
I couldn't stand to pivot
because it hurt at every point.

After 18 years in isolation, he was
released when it was established

that another man had
committed the murder.

However, the effects of isolation
have remained with him.

Only recently do I realise what I
paid for that solitary confinement.

I have no ability
with time whatsoever.

I can tell you whether I did
something or did not do something,

but I can't necessarily
tell you in what order.

I've lost the ability
to follow simple directions.

I cannot function

with anything that has too much
in the way of information coming.

I can't drive on a busy street.

In my opinion I have lost...

..two-thirds
of what was once my capability.

I am now ten years out,
it has not changed,

so I conclude that this is permanent.

The subjects have been
in the bunker for 40 hours.

# Looking from a window above
It's like a story of love... #

Barney seems to have
found a way of coping.

# Can you hear me? #

And Judy is still asleep.

But in the other rooms
it's a different story.

In the last sort of hour and a half
Adam's gone very quiet,
which is unusual for him.

For the first 25 hours, 26 hours,
every time that he was awake and
his eyes were open he was talking.

If he wasn't talking
he was doing something.

In the last while, he looks
almost as though he's been crying.

He's been rubbing his eyes
a few times and we were wondering,

was he going to say
"Okay chaps, I've had enough,
I really can't do any more."

So he may well be sort of struggling
at the minute

and wondering whether he should stay
or whether it's just too much.

I think I'm hitting a wall now,
in my mind.

HE SIGHS

I think over time it's becoming more
and more difficult for them to

sort of feel safe and keep
themselves distracted.

Another 24 hours might
really push that over the edge.

The long hours without stimulation
are creating some very
strange experiences.

Oh, God, I'm hallucinating now.
Tim, I'm hallucinating, cos
I can see a pile of...

of oyster shells,

like 5,000 oyster shells in a pile.

Oh, God.

Empty shells, to represent all
the food, nice food I could have
eaten while I've been inside here!

I go and touch them.

It's gone.

It's starting to appear now,
come back to me.

I hope someone can hear me.
I'm hallucinating.

'You would just see moving shapes,
lights, saw some little tiny cars,
zebras. You know, it was quite nice.

'The only things that were a
bit scary were the things

'that kind of tricked you that they were
real, like that there was somebody
in the room or something like that.

'That was a bit scary.'

'It was weird. I started imagining
things and thought the room was
taking off at one time as well.

'There was a load of fighter planes
buzzing round and that,
a swarm of mosquitoes.'

In the dark room people would
hallucinate because there's absolutely
nothing to focus attention on.

Now in the absence of information
the human brain carries on working

and processing information, even if
there's no information to process.

After a while it starts to
create that information itself.

Held in the dark for months,
Brian Keenan experienced
the most terrible hallucinations.

I can remember one distinctly,
because it was dreadfully
lucid and clear.

It was about being alone
and in a desert

and being very, very hot

and then being instantly

bone-numbingly cold.

Having the...the winds of the desert
stripping away,

as if you could feel
your flesh falling off you.

And so you were left as a bony hulk
shivering in the corner.

But they were not just
visual hallucinations
from which he was suffering.

I heard music

and it seemed to be coming
into the cell.

But I knew it wasn't, but I heard it.

It was all sorts of
instruments being played.

I heard bagpipes,
I heard African drums,

I heard zithers, flamenco guitars.

And it was really interesting

and then,
when it wouldn't go away after a few
minutes, it got really frightening.

And when I was frightened by it

the tempo of it lifted
and the volume of it lifted

and there were more instruments, and
cellos were playing and
orchestras, pianos,

and everything was happening
louder and louder and louder.

And then I got really afraid

and that's when I kind of started
banging my head against the wall,
just to make this go away.

It's a way you would try and engage
your mind forcefully on something
else, but it wouldn't go away.

And the intoxication of it was
not comforting

and it went on for
a very, very long time
until I was really frightened of it,

more frightened of the music in my
head than the man with a gun,
I'd say it myself.

Brian was finally released
four years later.

It took him many months
to rebuild his mind

and many more years
to rebuild his life.

It's the 47th hour, and amazingly
everyone has stayed the course.

The last sort of while has been
rather heavy and...

feeling the...pressure of...
being here.

Oh, I'm losing the will to think.

I'm losing... I don't have...

I'm just feeling numb now.

I don't want to talk to you.

At last, the long wait is over.

Hello, Clare. It's Ian.

Your 48 hours are up and
we're coming to get you.

OK. Thanks.

Hello, it's Tim. Oh! Oh!

Oh, you scared the life out of me!
Hello.

Sorry about that. Oh, God.

Adam, I'm speaking to you
because the 48-hour period of
the experiment has come to an end.

Ohhhh-ho-ho!

Oh, thank God!

I can't tell you, you've got
no idea how good this feels.

I thought you might be pleased.
Oh, I want to kiss you.

Hello, Judy.

Ahh. Excellent.

For some of the subjects
the past 48 hours have been
a dreadful experience.

Now the scientists will discover
just how the ability to do even
the simplest tasks has deteriorated.

The series of tests
carried out earlier is repeated.

The visual memory test.

The drawing that you drew earlier,

I'd like you to draw it
for me again, if you could.

Mickey really struggled to
recall the design after 30 minutes.

His memory's capacity
has fallen by 36%.

Several other subjects also
had their memories impaired.

But the effect on the central
executive, which controls the higher
functioning of the brain,

seems to have been more pronounced.

So I say the colour of these,
not the word? OK.

In the information processing test,
all the subjects found it difficult
to resist their first impulse,

to read the words written,
rather than the colour of the ink
in which they are printed.

Blue. Black!

But Adam does significantly worse.

Oh, it's so much harder.

It took him
69% longer to complete the test and
he made six times as many mistakes.

Red. Black!

Gosh.
This is painful!

You're nearly there.

Green, black.

Black, red.

That was just...

really hard.

Adam did particularly badly on
the tests of information processing.

Now, this could be down simply to
individual difference

but it could also be explained
by the fact that
Adam's particularly extrovert.

Extroverts set up their lives in a
way where they're constantly seeking
and receiving lots of information.

In the absence of the information
that ability
to process it was reduced.

Now I'm going to give you a letter
of the alphabet

and I want you to list as many words
as possible that begin with that letter.

So the first letter is F.

Fertiliser.

Bill struggles on
the verbal fluency.

In just 48 hours his central
executive's ability to pull together

memory and language to create
a category has been badly affected.

Er...er...

Gosh.

And the same has
happened to several others.

Er...

OK.

One Tuesday morning in July
the couple were leaving
the house to go to work.

For the scientists,
the most important test of all
is the suggestibility test.

Anna and John ran after the boy
and John caught hold of the
bicycle and brought it to a halt.

It reflects how sensory deprivation
makes subjects more vulnerable
to outside influence.

I'll ask you some
prompt questions, OK? Some prompts.

Was the boy frightened of
the big van coming up the hill?

I don't remember the big van,
coming up the hill either.

Was the boy frightened of
the big van coming up the hill?

Yes.

Did John grab
the boy's arm or shoulder?

I think he grabbed the bike.

Did John grab the boy's
arm or shoulder?

Arm.

On the suggestibility test
we see an increase in
the level of suggestibility

on the part of the men.

- Was the boy frightened of the big
van coming up the hill?
- Yes.

Both women didn't show any increase
in suggestibility whatsoever,

but the men all had quite
a marked increase in suggestibility.

This leads me to think that when
put under that sort of stress of
reduced sensation,

this particular group of men
were more likely to start to
question their own recall,

question their own beliefs
and be willing to
take somebody else's viewpoint.

It's a controversial conclusion,
throwing doubt over evidence

gathered from people held
in sensory deprivation.

I think it's very important,
this increase in suggestibility when
exposed to sensory deprivation,

because in many parts of
the world people are held in
situations of sensory deprivation.

That means that the evidence that is
accumulated in those places must be
considered very unreliable

because people will, after a while,
start to take on board the views of
their interrogators.

Overall, the tests show for
the first time the critical impact

of such conditions on
the functioning of the
central executive.

We see a reduction in the speed
of information processing.

We see a reduction in ability
to abstract and verbal fluency.

And we see an increase
in suggestibility.

All those would suggest
a deterioration in the functioning
of the central executive.

After two days underground,
the subjects are finally released.

How does it feel to be out?

Fantastic. Absolutely fantastic.

God, I think I'll see this
for a while.

Emotional.

God, sunlight.

Lovely day, innit? Beautiful.
Absolutely beautiful.

How does it feel to be out?
Unbelievable.

God, I never thought a nuclear
bunker would look so beautiful.

It's actually amazing.
Is that all the flowers?

When we arrived I saw the ugliness
and now, now I'm seeing all the...

I'm hearing the birds, I'm seeing
the clouds and the green and
the yellow, the buttercups.

Two days is actually
an incredibly long time to not
see any sunlight, isn't it?

It's the longest in
my life I've ever gone.

That's just great. Ohh!

Our volunteers were in a sensory
deprivation environment for 48
hours, and being treated humanely,

and if they can have quite
marked effects on their memory
and concentration

it gives us a great insight
into what can happen to people

kept in solitary confinement over
possibly many months or even years.

Four decades after the last
examination of sensory deprivation,

these findings suggest just how
fragile the human mind can be

when confronted with the simple
reality of being left truly alone.

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