Vegetative patients 'still learn' 植物人“仍然有学习能力”
文章来源:未知 文章作者:meng 发布时间:2009-09-22 03:20 字体: [ ]  进入论坛

Patients with severe brain damage who do not appear to have signs of consciousness still seem able to learn, a Cambridge University study suggests.


Researchers hope the test will help determine which patients may recover
Researchers hope the test will help determine which patients may recover

Researchers tested for Pavlovian-like responses in 22 people in a persistent1 vegetative state by playing a noise prior to a puff2 of(一阵) air to the eye.

Some subjects learnt to anticipate the puff of air causing the eye muscles to twitch3, Nature Neuroscience reported.

The team hopes it may lead to tests to determine which patients could recover.

Study leader Dr Tristan Bekinschtein from the University of Cambridge said the consensus4 had been that learning to link one stimulus5 with another - in this case a noise and a puff of air - was dependent on explicit6(明确的,详述的) awareness7 of the association.

But the study, where up to 70 puffs8 of air were delivered over a 25 minute period, showed that this sort of conditioning is possible even in patients who, by all other measures, are not conscious.

Electrodes positioned by the eyes picked up whether the muscles began to respond or not.

And a control experiment doing the same tests on people under general anaesthesia(麻醉,麻木) did not produce the same responses, suggesting that the learning does not happen when truly unconscious, and that some patients may have some level of consciousness not apparent on traditional tests.

Sign of recovery

Dr Bekinschtein, who began the work as a PhD student in Argentina, said they also found that patients who started to anticipate(预期,期待) the puff of air were more likely to show signs of recovery later on, in terms of increased ability to communicate.

Although the results are reported in 22 patients, some of whom were in what is termed a "minimally9 conscious state", the team has since used the test in many more and is planning a large clinical trial with colleagues in the US and Belgium.

"These were classic Pavlovian experiments and some patients, but not all of them, started to respond.

"They were clearly anticipating the stimulus would come, so there is some kind of perception and from the point of view of the patient who is allegedly unconscious this could have profound implications," he said.

He said an exciting aspect of the study was that the test was easy to do and could be carried out without specialist equipment.

"This is potentially a test that could be used to test the consciousness of the patient.

"Interestingly about 80% of those who showed learning had some improvement so it gives us some confidence that we can predict those who will show some level of recovery," he added.

Professor Christopher Yeo, an expert in behavioural neuroscience(神经系统科学) at University College London, said the results looked interesting although the effects seen were small.

"All the data is extremely subtle(微妙的,敏感的) so a study in a bigger group will improve the reliability10 of the findings," he said.

"The only thing I would say in terms of practical relevance11 is the subjects who don't learn are the ones who don't improve their condition but among those who do learn there is even distribution(分配,散布) between those who do and do not improve."


1 persistent BSUzg     
  • Albert had a persistent headache that lasted for three days.艾伯特连续头痛了三天。
  • She felt embarrassed by his persistent attentions.他不时地向她大献殷勤,使她很难为情。
2 puff y0cz8     
  • He took a puff at his cigarette.他吸了一口香烟。
  • They tried their best to puff the book they published.他们尽力吹捧他们出版的书。
3 twitch jK3ze     
  • The smell made my dog's nose twitch.那股气味使我的狗的鼻子抽动着。
  • I felt a twitch at my sleeve.我觉得有人扯了一下我的袖子。
4 consensus epMzA     
  • Can we reach a consensus on this issue?我们能在这个问题上取得一致意见吗?
  • What is the consensus of opinion at the afternoon meeting?下午会议上一致的意见是什么?
5 stimulus 3huyO     
  • Regard each failure as a stimulus to further efforts.把每次失利看成对进一步努力的激励。
  • Light is a stimulus to growth in plants.光是促进植物生长的一个因素。
6 explicit IhFzc     
  • She was quite explicit about why she left.她对自己离去的原因直言不讳。
  • He avoids the explicit answer to us.他避免给我们明确的回答。
7 awareness 4yWzdW     
  • There is a general awareness that smoking is harmful.人们普遍认识到吸烟有害健康。
  • Environmental awareness has increased over the years.这些年来人们的环境意识增强了。
8 puffs cb3699ccb6e175dfc305ea6255d392d6     
n.吸( puff的名词复数 );(烟斗或香烟的)一吸;一缕(烟、蒸汽等);(呼吸或风的)呼v.使喷出( puff的第三人称单数 );喷着汽(或烟)移动;吹嘘;吹捧
  • We sat exchanging puffs from that wild pipe of his. 我们坐在那里,轮番抽着他那支野里野气的烟斗。 来自辞典例句
  • Puffs of steam and smoke came from the engine. 一股股蒸汽和烟雾从那火车头里冒出来。 来自辞典例句
9 minimally 0e3844f43172f471e75a897f7b3116da     
  • Food spoilage problems occur with minimally processed, concentrated frozen citrus products. 食品的变质也发生在轻微加工的、浓缩冷冻的柑橘制品中。
  • So, minimally, they are responsible for such actions and omissions. 所以,至少来说,他们要对这样的行为和忽略负责。
10 reliability QVexf     
  • We mustn't presume too much upon the reliability of such sources.我们不应过分指望这类消息来源的可靠性。
  • I can assure you of the reliability of the information.我向你保证这消息可靠。
11 relevance gVAxg     
  • Politicians' private lives have no relevance to their public roles.政治家的私生活与他们的公众角色不相关。
  • Her ideas have lost all relevance to the modern world.她的想法与现代社会完全脱节。
TAG标签: damage patient brain learn