Today’s video is called “One More Reason to Get a Good Night’s Sleep,” and is given by Jeff Iliff – a neuroscientist. This video contains a lot of difficult vocabulary, and the focus of this lesson is to train you for a valuable IELTS Listening skill – focusing on the question, and not getting overwhelmed by difficult words and ideas.


We’re going to use a very difficult video today to teach a simple idea. That is – You don’t need to understand everything! Today’s speaker is Jeff Iliff, a neuroscientist talking about brain functions. Does the average native English speaker understand the jargon of neuroscience? Of course not. But we can still get the gist of what is being said, if we listen carefully.

An important IELTS Listening skill is paying attention to main ideas, and to listen for key details. You are not being tested on your knowledge, and you will not be expected to know difficult scientific terminology. In the listening exam you will be expected to ignore the difficult parts and get the answers you need. That means staying cool under pressure and not being intimidated by jargon.


Let’s start by looking at some useful vocabulary from the video. We will not pay attention to words and phrases which are too obscure.

Prominent adj. – foremost, or obvious

Nutrients n. – a substance which provides nourishment

Rehydrating v.  – after water is lost from the body, it should be returned through rehydration

Byproduct n. – in the process of creating one thing, a byproduct may be produced

Murky adj. – the opposite of clear – used literally in describing water, or figuratively regarding a situation

Ingenious adj. – very clever

Restorative adj. – having the properties necessary to return something to its original levels

Repurpose v. – to give something a new use

Blood vessels n. – the network that carries blood through a living body

Alzheimer’s n. – a disease affecting the human brain

Vocab Test

Use the above vocabulary to fill in the blanks. (Answers are at the bottom of this page.)

  1. My grandfather is often irritable and confused because he has __________.
  2. Jack Kerouac was one of the ________ authors of the 1950s.
  3. The athlete was exhausted after the marathon and spent hours _________.
  4. We thought it was an __________ invention.
  5. Everybody knows the ___________ effects of sleep.
  6. The water was __________ so we didn’t dare drink it.
  7. “Eat this,” she said. “It’s full of _________ so it’s good for you.”
  8. It seemed like a waste until we found a way to _________ the old computing equipment.
  9. Arteries and veins are both kinds of _________________.
  10. He saw poverty as a ___________ of prosperity.

Listening Practice

Watch the following video. It will last 11:45. Try to answer the following questions to test your comprehension. If necessary, watch the video twice. Make notes to help develop your note-taking skills.




Comprehension Questions

  1. What is the main idea of this lecture?
  2. Who was Galen?
  3. How much energy does the brain use?
  4. How does the brain clean itself?
  5. When does this process occur?
  6. What does this cleaning process prevent?


Watch the first 01:17 minutes of the video again and fill in the blanks:

Two thousand years ago, Galen, one of the most ____1____ medical researchers of the ancient world, proposed that while we’re awake, our brain’s motive force, its juice, would ____2____ to all the other parts of the body, animating them but leaving the brain all dried up, and he thought that when we sleep, all this ____3____ that filled the rest of the body would come rushing back, ____4_____ the brain and refreshing the mind. Now, that sounds completely ridiculous to us now, but Galen was simply trying to explain something about sleep that we all deal with every day. See, we all know based on our own experience that when you sleep, it _____5_____, and when you don’t sleep, it leaves your mind murky. But while we know a great deal more about sleep now than when Galen was around, we still haven’t understood why it is that sleep, of all of our activities, has this incredible ____6_____ function for the mind.

True or False?

Listen to the material and answer true or false to the following statements:

  1. His presentation is based upon old research.
  2. It is critical for the brain to receive a constant supply of nutrients
  3. Every cell produces waste
  4. The brain’s waste clearance solution was unexpected for the researchers
  5. CSF is pumped into the brain on the inside of blood vessels
  6. Galen’s theory was completely wrong
  7. Worsening sleep quality may increase the chance of developing Alzheimer’s
  8. Our brains rest when we sleep


Questions you might hear in the IELTS speaking exam on the topic of sleep, from part one.

  • How many hours do you sleep each night?
  • Why is it important to get a good night’s rest?
  • Do you take a nap during the day?
  • Do you get the same amount of sleep every night?
  • How much sleep do you get on weekends?
  • Do you think you get enough sleep?
  • Do you like getting up early in the morning?
  • Do people sleep more when they are children or elderly?
  • Do you remember your dreams?
  • What do you dream about?
  • Do you find it easy to fall asleep at night?

Model Answer:

Q: Do you think you get enough sleep?

A: Well, that depends on the day. During the week I study late and get up for class early, so I probably don’t get enough sleep. However, on weekends I make up for it by sleeping in late. Sometimes I take a nap in the afternoon to catch up on some rest.

A question you might hear in the IELTS speaking exam on the topic of sleep, from part two:

“Describe a time you didn’t get enough sleep.

You should say:

Why you weren’t able to sleep enough

What happened during that time

How you caught up on sleep

How you can ensure you get enough sleep in future.”

Model Answer

I remember when I was studying for my high school exams and I was very stressed. I felt that I wouldn’t be able to pass them with my regular study schedule, so I stayed up particularly late at night for two weeks in order to fit in more study time. The result was that I only slept about four hours each night. To be honest, I didn’t feel too bad after the first week, and I got used to functioning with less sleep than optimal. However, although I didn’t notice it at first, I began to make stupid mistakes and found myself forgetting too many things, so the self-deprivation was obviously affecting me. I resolved to sleep more, and found that even though I spent less time study, the quality of my studying was higher. In future I’ll always try to get more rest because it’s worthwhile to have your brain functioning better, even if you have fewer hours awake.



Vocab test

  1. Alzheimer’s
  2. Prominent
  3. Rehydrating
  4. Ingenious
  5. Restorative
  6. Murky
  7. Nutrients
  8. Repurpose
  9. Blood vessels
  10. Byproduct


  1. It is about the process through which the brain cleans itself – how it receives and disposes of nutrients
  2. He was a prominent medical researcher of the ancient world
  3. It uses one quarter of the body’s energy, despite only being 2% of its mass
  4. It cleans itself using cerebrospinal fluid, known as CSF
  5. It occurs while we sleep
  6. It can help to prevent Alzheimer’s


  1. Prominent
  2. Flow out
  3. Moisture
  4. Rehydrating
  5. Clears your mind
  6. Restorative

True or False

  1. F – it is based upon recent research
  2. T
  3. T
  4. T
  5. F – on the outside of blood vessels
  6. F – he may have been correct
  7. T
  8. F – they never rest