Are you introverted or extroverted? To answer this question, most people take into consideration if they are having fun at parties, problems to strike up conversations with strangers or if they can speak in public without stress.
But the problem with this approach is that is not much objective. We should answer honestly, and it is difficult not to fall into self-deception and reconfirm the ideal image we have of ourselves.
A completely different approach to answering this question involves the use of a lemon, or better, of a concentrated lemon juice. In fact, it is a test that has a long history in the context of Personality Psychology, and is very easy to do at home.
You only need a cotton swab (cotton buds), to which you will have to tie a wire exactly in the center. Now you have to put one of the ends of the cotton swab on the tongue for 20 seconds. Now remove the stick and put five drops of concentrated lemon juice on the tongue, swallow and put the other end of the cotton bud on the tongue for 20 seconds. Finally, take the cotton swab and leave it suspended by holding it with the wire.
At this point you will see if it remains more or less in an horizontal position, or if the tip that you used after swallowing the juice of lemon hangs lower down, meaning that is heavier. If this ends hangs down it will be because the lemon juice made you salivate more than usual, which is a physiological signal that you are an introverted person. Conversely, if the cotton swab remains relatively horizontal, it means that you have not reacted very strongly to the lemon juice and you’re probably an extroverted person. Why? How it is explained this phenomenon?
Introverted people react more strongly to stimuli
In reality, this simple experiment dates back to the mid-1960s, and was carried out by the pioneers of Personality Psychology, Hans Eysenck and Sybil Eysenck.
In the original experiment, psychologists used these tools to measure the amount of saliva absorbed by cotton before and after people were exposed to lemon juice. These researchers wanted to confirm the “theory of cortical arousal” about extroversion and introversion.
According to psychologists, these characteristics of the personality have a physiological basis, so that introverted people have a higher baseline cortical excitation, which makes they react more intensely to stimuli. In practice, introverts have higher cortical activation, which would explain why they tend to be more persevering and prefer to avoid social activities that cause excitement.
In contrast, extroverts have lower cortical activation, for this reason they’re constantly looking for situations and activities that generate excitement. Thus, the Eysenck discovered that introverts tend to salivate more in response to lemon juice and that the extroverted did it less.
However, today we know that although extraversion and introversion have a biological and genetic component, the arousal theory is only half true. There is ample evidence to suggest that introverts tend to respond more strongly to loud noises and other sensory stimuli. But contrary to Eysenck’s theory, there is little evidence that introverts have a higher level of baseline arousal.
Therefore, although the Lemon test can not accurately predict whether you are extroverted or introverted, it gives you some clues about your physical sensitivity. If want to try it, you should repeat it at least a couple of times to get the most reliable results.
Your reaction to the lemon reveals your degree of empathy
In any case, the lemon test can also give other clues about your personality. A recent research conducted at the University of Zurich has used lemon to determine the level of empathy. These psychologists asked participants to put three pieces of cotton in their mouth to collect saliva.
Meanwhile, they had to see two videos of one minute each, the first showed a man moving colored balls, in the second they saw a man who cut and ate a lemon.
After analyzing the cotton pieces psychologists have found that participants drooled more seeing the man who was eating lemon, a reaction known as “self-resonance”, ie, we have a tendency to automatically mimic the physiological states of others, such as when we yawn when we see someone yawning. In fact, with MRI we have seen that when we see a person suffering in our brain are activated the same areas related to pain, which is due, among other things, to the activation of mirror neurons.
However, people differ in the degree of sensitivity, that was found from the amount of saliva. Psychologists have found that more empathic people drooled more.
Of course, doing this test at home is more complicated because it would be necessary to have evidence of others to compare the results. Yet, they are interesting experiments that help us to understand that the body and mind are an indissoluble unity.
Sources:
Jarret, C. (2016) What can a lemon tell you about personality? BBC.
Hagenmuller, F. et. Al. (2014) Juicy lemons for measuring basic empathic resonance. Psychiatry Research; 219(2): 391–396.
Sybil, B. G. Y Eysenck, H. J. (1967) Salivary response to lemon juice as a measure of introversion. Perceptual and Motor Skills; 24: 1047-1053.
