Dosing someone with coffee or another strongly caffeinated drink may make them more susceptible to persuasion, according to a recent study, reported in New Scientist.
Previous studies have show that consuming caffeine can improve one’s attention and enhance cognitive performance, with 200 milligrams (equivalent to two cups of coffee) being the optimal dose.
Moderate doses of caffeine can also make you more easily convinced by arguments that go against your beliefs, say Pearl Martin of the University of Queensland in Brisbane, Australia, and her colleagues.
In 2005, her team published a paper suggesting that the compound primes people to agree with statements that go against their typical views because it improves their ability to understand the reasoning behind the statements.
After a bit of a search, it seems the full paper is freely available online.