Hello, it's your host, Andrew here. If you're enjoying Send Me to Sleep so far and you'd like to

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before the show begins. It's really fascinating to me the reason why it is that caffeine keeps us awake, when

consumed in a particular amount, of course. And I can't actually remember when I first learned about this but I don't know I think there's

something curious about it and if you're not familiar let me see if I can try and explain a little bit

about it so when we feel tired, what builds up in our brains is referred to in sleep science as

sleep drive or sleep pressure.

And that sleep pressure is a literal build-up of a particular neurotransmitter called adenosine.

And there are receptors in the brain for adenazine specifically. And there is a correlation

between the amount of adenazine that has built up and been received by these receptors, and how tired we feel at night,

or indeed at any time that we feel tired or have lacked sleep.

And of course, this is not the only thing that makes us sleepy. It's quite a complicated.

Part of our biology, there are many other factors that need to combine to create sleepiness as we know it.

But this is certainly one of the bigger parts

that contributes towards the feeling of sleepiness

and the reason that caffeine keeps us awake

is because it is actually

molecularly rather similar to a genocene in shape as such that it is actually capable of fusing with the adenosine

receptors in the brain, effectively clogging them up and blocking the ability of the actual adenosine

to connect and send these signals to our brain to let us know that we are, in fact, tired.

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