THINK YOU’RE INTROVERTED? TRY LICKING A LEMON!

THIS unique introversion test was first devised in the 1960s by a German psychologist called

Hans Eysenck and his wife Sybil.

Since introverts are more sensitive to external stimuli than extroverts, Eysenck guessed they should produce more saliva after drinking acidic, tangy lemon juice.

Participants in his study drank a few drops of lemon juice and the amount of resulting saliva was measured using a ball of cotton wool – the heavier the ball, the more saliva had been produced.

But there’s a far simpler approach – using a sheet of A4 paper and a lemon. Lick the paper continuously, lengthways, from one end of the paper to the other, until you run out of saliva and your tongue starts to stick. Stop and mark this point using a pen.

Next, squeeze three to four drops of lemon juice on to your tongue and repeat the licking exercise on another sheet of paper.

How much further can you go before you tongue dries out? In my case, it would seem Eysenck’s prediction was correct: I went three times longer after applying the lemon juice.

My wife, Clare, the extrovert, went only twice as far.