When Should Introverts not Drink Coffee

Have a quick coffee before the conference to improve concentration – this could backfire for introverts, researchers say. Why?

When an important meeting or presentation is due at work, we often empty a cup of coffee shortly before to spur our brains to peak performance with a caffeine kick. For people who tend to have an inward-looking personality, however, this strategy could be counterproductive, writes psychologist Brian Little in his recently published book

After about two cups of coffee, extraverts perform tasks more efficiently, whereas introverts perform worse afterwards. This effect increases when numbers and data are involved and there is time pressure.

A strange thesis at first sight – which Brian Little, lecturer at the renowned University of Cambridge, the now explained in more detail. His observation is based on the theory of extraversion established by Hans Jürgen Eysenck and on studies by the psychologist William Revelle of Northwestern University. “Introverts and extraverts have differently active cells in their cerebral cortex and therefore interact differently with their environment,” said Little. According to Eysenck’s theory, these cells tend to be over-stimulated in introverts, while they are usually under-stimulated in extraverts.

“If introverts find themselves in situations associated with excitement or nervousness, or take a pick-me-up like coffee, they move even further away from optimal cell stimulation – which in turn impairs their performance,” Little continues. He therefore recommends that introverted people avoid caffeine before important appointments. A noisy, bustling place has the same negative effect, by the way, because the central nervous system of introverts is quickly over-stimulated. So if you have a more reserved personality, treat yourself to a moment’s rest in the fresh air before your next business meeting – without a coffee cup. It’s worth a try.