You will hear a recording. Select the paragraph that best relates to the recording.
(1) Modern classrooms and offices don’t help people’s brains to work well. This is because they discourage exercise. Exercise boosts brainpower because during exercise the brain produces a protein that encourages brain development. Our ancestors did a lot more exercise than us and this helped them to survive.
(2) Brainpower is a survival technique that helped our ancestors. They had to do a lot of exercise and this creates proteins called BDNFs, which help the brain to develop. This is how humans have survived for so long and been so much more successful than other species.
(3) Our brains produce a special protein when we exercise, which helps the brain to grow and develop. This chemical was important for our ancestors due to the unstable and fast-moving environment in which they lived. However, in our current environment, we get this protein in other ways.
(4) People who work or study in modern classrooms or offices don’t get much exercise. Nowadays many people do little except sit and lie down, which isn’t good for proteins in the brain. This contrasts with our ancestors, who walked around 12 miles each day in their struggle for survival.