Sciencespeaking topic

Caffeine doesn't cut off sleepiness, it 'hides' it: it blocks the adenosine receptors in the brain while adenosine keeps building up. Why are we twice as tired once the coffee wears off?

— adenosine receptor antagonism

practice with this topic

Set the timer (5-30 min), take 20 seconds of prep if you like, start talking. Jot your thoughts onto the sticky-note board.