That's men for you: Padraig O'Morain's guide to men's health.
Why is it that when you snap at your significant other, she snaps back?
And why is it that when she whispers sweet nothings in your ear, you purr like a marmalade cat?
Part of the answer to these questions - and some hints as to how we might improve our relationships - can be found in the existence of "mirror neurons" in our brains.
Put simply, mirror neurons ensure if I see you being angry, my brain will "mirror" your anger. If I see you being pleasant and comforting, then those parts of my brain that create the feeling of pleasantness and of comfort will be activated.
You can study this phenomenon with MRI scans or by attaching electrodes to neurons in your brain although it is not generally recommended to try this at home.
Mirror neurons have been studied quite intensively for more than 10 years now and I suspect that they are about to become the next big thing.
I suspect this because Daniel Goleman, whose book, Emotional Intelligence, was one of the big things of the past 10 years, has made mirror neurons the subject of his new book, Social Intelligence.
Each thought, emotion or action we perform requires certain neurons (nerve cells) to activate. Ten years ago, researchers at the University of Parma in Italy discovered that if you watch somebody performing an activity, the same nerve cells will activate in your brain as in theirs.
Further work in Italy, France and the United States even suggests that when you watch or hear a person expressing an emotion, the network of neurons that corresponds to that emotion activates in your own brain.
Have you ever noticed that there are people who can "bring you down" with their moaning and groaning?
This is, at least partly, because as you observe their gloom, your "gloom" neurons activate and the other person's gloom becomes part of your own experience.
But there are also people in your life, I hope, whose good humour takes you "out of yourself" and you feel better when you are with them.
As you observe their good humour, your "good humour" neurons activate and you thereby get into a good mood yourself.
How does it help to know this? I would suggest that this information is extremely valuable in helping us to improve relationships.
If your partner is being a bit tetchy, you can realise that your brain is about to begin mirroring her tetchiness. You can then make a choice to stay calm or to follow her into a row.
If you remain calm, good-
humoured or sympathetic long enough for her brain to mirror your good humour, then there is a better chance that she will get out of her bad mood.
If you want to get her into a good mood, your best chance of succeeding is to be in a good mood yourself and to persist in that good mood.
Don't push this thing too far, though. If her tetchiness is due to you landing home from the office Christmas party at six in the morning with lipstick on your collar, then mirror neurons might not save you.
Still, this information explains, I think, the value of emotional support. Giving emotional support to someone else actually changes what is going on in that other person's brain.
This might explain why criticism annoys people so much. While you are expressing your criticism, the other person's brain is mirroring your anger. Therefore, there is little chance of your criticism being welcomed by your listener.
Mirror neurons may even help explain why the bully in the workplace can have such a devastating effect on his or her victim.
The contempt being expressed by the bully is actually mirrored in the victim's brain and becomes part of the victim's experience.
The victim needs to learn to interrupt the mirroring by deliberately thinking different thoughts while the bully is speaking.
The basic lesson from this information is that you are more influential than you think you are: you get back what you give out.
Padraig O'Morain is a journalist and counsellor accredited by the Irish Association for Counselling and Psychotherapy