We talk sometimes about someone’s laugh being infectious – did you know that it really is? I love this bit of science, because it says so much about what we’re really like as humans.

So, in our brains, we all have something called mirror neurons. Thye detect the facial expression of others and switch on our facial muscles to mirror their expression. We may not exactly reproduce their smile or frown, but the micro-muscles that create that expression are switched on and begin to move. And the micro-muscular movement in our faces is directly driven by our emotions at the time – it can’t be disguised. We all know that we can tell the difference between a false smile and a real one, and our mirror neurons are what detect the difference for us – we mirror it and then feel the difference in ourselves.

This is a level of biological empathy that we may not be aware of, but it is built into us. Scientists believe that it is part of our survival mechanism: we need to relate to and understand others in order to thrive, and by re-creating their facial expressions in ourselves, we get a sense of what they’re feeling and therefore how to respond to them.

This is one of the reasons why communication is so much more effective when it’s face-to-face – we are much more aware of what is going on with the other person, because we are replicating it in our bodies. It also explains why moods are ‘catching’, and whole groups of people can be affected by someone’s mood at the time.

So since we are so powerful, let’s use it for the good! If I know that others will pick up on my facial expression and therefore my mood, I can consciously choose to shift my state to a good one. If I am feeling frustrated standing in a queue, I can choose instead to use the time to spread some friendliness to those around me. If I am feeling fed up today, I can look for someone who looks happy, and let them infect me! And when I’m feeling good, then I can catch the eye of others and give them a dose of my good mood!

Come on, let’s infect the world with our good moods, and lighten our life!