Deleting memories
删除记忆
我们都会有想要忘记的伤心回忆。不过，科技的发展真的能帮助我们删除掉那些不想要的记忆吗？新研究结论指出这样的猜想将成为可能。
今天，Rob和Finn将会在节目中和大家一起聊聊关于这个新研究结论，以及学习和大脑相关的词汇。
本期问题：
科学家认为我们人类的大脑有多少的神经细胞呢？有：
a) 8百万到1千万
b) 8千万到10亿
c) 80亿到100 亿
让我们一起听节目，找答案吧。
听力内容：
Deleting memories
NB: This is not a word-for-word transcript
Finn: Hello and welcome to 6 Minute English. I'm Finn.
Rob: And I'm Rob.
Finn: Rob, I'm going to ask a personal question – do you have any bad memories?
Rob: Yes. When I was young I was bitten by a dog. And he bit my arm. Not nice.
Finn: Really? Do you ever wish you could delete – or remove – that memory?
Rob: Oh yes, absolutely. Yes. I don't want to remember that.
Finn: OK. Well, today we'll be talking about new research that has successfully deleted memories. We'll also explain some vocabulary related to the brain. But, as always, first let's start with a question.
Rob: A good idea Finn.
Finn: We're talking about the role of neurons in the brain – these are the cells that transmit information. So, roughly how many neurons do scientists think we have? Is it:
a) 8-10 million
b) 8-10 billion
c) 80-100 billion
Rob: Wow. I know we have a lot of neurons; however, a 100 billion would be a lot to get into your brain, so I'm going for the small number, 8 to 10 million.
Finn: OK, Rob. We’ll find out if you are right or wrong at the end of the programme. So, how have scientists managed to remove specific memories? Well, the research was carried out in the Netherlands at Radboud University, Nijmegen.
Rob: Yes, they've been using something called ECT – electroconvulsive therapy – this treatment involves electric pulses through the brain.
Finn: Yes – it's quite a controversial treatment, partly thanks to films like One Flew over the Cuckoo's Nest, where a terrified patient is strapped to a table and forced to receive these shocks…
Rob: But it's used as a last resort – a last option - for people with severe depression. Now, in this study they've been looking at neurons – and memories are actually stored in the connections between these neurons, according to Dr Martin Kroes on the team.
Finn: He says these connections take some time to become permanent, and "if you disturb this process, you lose the connection between the brain cells altogether".
Rob: So, if you lose the connection – you lose the memory. That was the idea. Could they make it work in an experiment? Listen to BBC reporter Anna Holligan talking about what happened to the patients.
BBC reporter Anna Holligan:
Participants were patients already being treated with ECT. They were shown two sets of picture cards each telling a story. Then just before an ECT session they were shown one of the stories again to reactivate that particular memory. The results were remarkable, after the ECT they forgot the story they just looked at, while the memory of the other story was unaffected.
Finn: So – patients were shown two sets of cards. Then, just before ECT, they were shown one of the sets again to reactivate it – to make it active again.
Rob: They then had ECT – and when they woke up, they forgot the memory of the card they had just looked at – the one that had just been reactivated.
Finn: Yes. Now, we should mention that one of the side-effects of ECT is memory loss – so why is this surprising? It's because they were able to target specific memories.
Rob: OK. Well, it's thought that this new technique could help people with PTSD – post-traumatic stress disorder. It's a memory-related illness where people who experience something very stressful and upsetting, something traumatic, such as war, continue to be affected by it psychologically.
Finn: Yes, the hope is that these traumatic memories could be deleted.
Rob: Which would be an exciting development. Now, before we forget, let's remind everyone of today's question.
Finn: Yes, very good. Well, it was about the number of neurons in the human brain. Now, are there:
a) 8-10 million
b) 8-10 billion
c) 80-100 billion
Rob: And I thought it was just a mere 8 to 10 million.
Finn: Well there are, supposedly, 80 to 100 billion of these things in our brains. Not all scientists agree on the exact number. But still it's about as many as there are stars in the whole Universe.
Rob: It would take forever to count those!
Finn: I don't know who's counting – one by one! Now, Rob, can you remind everyone about today's vocabulary?
Rob: I think that memory has been removed!
Finn: Oh, it's been deleted? OK!
Rob: Only joking.
Finn: You have it?
Rob: Yes, I have it now, it's come back to me! We heard:
delete
neurons
pulses
controversial
a last resort
depression
reactivate
PTSD (post-traumatic stress disorder)
traumatic
Finn: Thank you very much Rob. And that's it for this week's 6 Minute English. We hope you’ve enjoyed today’s programme. Please join us again soon.
Rob: Bye.
Finn: Bye.
词汇学习：
1. delete 删除
2. neurons 神经细胞
3. pulses 脉冲
4. controversial 有争议的；有争论的
5. a last resort 最后一招
6. depression 抑郁（症）
7. reactivate （使）恢复活力
8. PTSD (post-traumatic stress disorder) 创伤后压力症候群
9. traumatic 创伤的
耀世紫辰
Wow great