At work, are you noticed first or perhaps it is the other people around you? Do you feel compelled to take centre-stage or are you more comfortable back-stage?

If it's the former, then you are usually eager for contact — warm and happy human relations. If it's the latter, then solitude suits and stimulates you more, and hell can be other people…

Notice the qualifying words in the statement above – usually, more, can be. You probably have guessed we are talking about introverts and extraverts.

Common knowledge dictates that introverts are quieter and tend to feel more energised from spending time alone while extroverts are louder and gain reinforcement and energy from being with others. Extroverts often exhibit qualities of charm, charisma and persuasion, while introverts tend to be creative and prefer to work alone. But is it true? Could it be that that some people are noisy pains in the arse, and some are just witheringly withdrawn?

To some extent they answer is yes but some indications from neuroscience have shown that the brains of introverts and extroverts are activated differently depending on their circumstances, and it has a lot to do with dopamine, a neurotransmitter that controls the brain's reward and pleasure systems. Those that are slower to be activated need to expend more energy for reward and they we find are extraverts. There are also some structures in the brain that are different. A 2012 study completed by Randy Buckner of Harvard University discovered that introverts tended to have larger, thicker grey matter in their prefrontal cortex — a region of the brain that is linked to abstract thought and decision-making — while extroverts had less grey matter. Buckner concluded that this might be accountable for introverts' tendencies to sit in a corner and ponder things thoroughly before making a decision, and extroverts' ability to live in the moment and take risks without fully thinking everything through (which has its pros and cons, of course). One issue is that these things are not in isolation. How much of a difference is there and are there other neuro-biological effects and structures? Do self-answered questionnaires really indicate the differences between people particularly if they have been raised in different cultures or societies? We know, for example that Finns are more introverted than Americans, or so it would seem. We also know as soon as we start to explore the brain that the grey matter concentration, for example, with a special focus on the amygdala, indicate relationships between extraversion and neuroticism. Not something talked about. I raise it as every part of the brain at some stage is in contact with every other part and the patterns of resulting behaviour is both individual and ever developing.

Just to try to put some balance into the split between E's and I's. A questionnaire such as the Myers-Briggs tends to split the population 55% E and 45% I. Other tests such as 16pf or the Big 5 tend to split them Extraverts (75%) and Introverts (25%) of population. Research designed specifically to explore the proportions of E's and I's give ambiguous results but a general finding is that most people are ambiverts with a small but persistent bias to E or I, more usually to E. This bias may be due to cultural or social factors but the latest research does indicate some neurobiological differences.

Having raised the doubts and the indications we have, let us define what we mean and work from there for good or ill.

Introverts (or those of us with introverted tendencies) tend to recharge by spending time alone. They lose energy from being around people for long periods of time, particularly large or noisy crowds.

Extroverts, on the other hand, gain energy from other people. Extroverts find their energy sapped when they spend too much time alone. They recharge by being social.

Which one are you? Me, easy, I am an introvert. I can, and do spend hours researching stuff. Has this affected my working life? Um no. Royal Navy (Licenced Aircraft Engineer) plus a degree in psychology, BOAC (British Airways) training, pilots, engineering officers and ground engineers to meet CAA licence standards; management and general training manager; manager organisation development; HR manager; director European Learning Institute; director at Learning Partners Limited and fiction author. The final role you will note is a classic role for an introvert, but I am now also a non-executive director keeping me in touch with friends and industry. A lifeline, introverts are not isolates.

Look over your life and ask the questions such as has my personality helped or hindered my career? What have you considered and has that reflected the education and training you have had? Have factors such as intelligence helped or hindered you. What difference do you think mum and dad had?

Lastly, why on earth would I ask these questions?