Huffington Post: In your opinion, do you have to be proactive about positivity?

One of the sayings in neuroscience is 'neurons that fire together wire together'. Another way of saying this is 'what we dwell on we become'. This is all based on the understanding that our minds and brains are highly plastic - that is they are changing all the time. We can learn to direct the course of that change by taking some control over how we use our minds and what we pay attention to. If you pay attention to things that boost positivity then you will,quite naturally, become more positive. If you dwell on difficult things and brood - ruminate to use the technical term - then this will become a habit. Why not create habits that are moving towards the positive as this will lead to a much better life both for yourself and those you relate to (as they will in turn be positively affected by your positivity!)?

It also is a way to overcome the 'negativity bias' which is part of our evolutionary heritage. Our ancestors needed to be very alert to dangers in order to survive, whereas positive experiences were less crucial to survival. This means we carry the tendency into the modern world of tending to focus more on the negative than the positive. Being proactive about noticing and dwelling upon positive things will gradually change the negativity bias so it has less of a hold upon us.

What benefits does being positive bring to your life?

Being positive will make your experience of life far more joyful and pleasurable. Perhaps as importantly, it will make your encounters with others more joyful and satisfying and this will lead to a much richer and happier social life. If you are grumpy and irritable then others will tend to avoid you; if you are a positive person then you will be like a magnet to others and your life will expand and become more interesting and satisfying. This will mean you attract other positive people into your life which will in turn feed your own positivity in a virtuous spiral. And so it will go on and, over time, your quality of life can change for the better to an extraordinary degree.

Why do positivity challenges help?

They focus our attention and encourage us to notice positive things. Life in general contains a whole variety of experiences - some difficult, some positive - and if we don't make the effort to notice positive things they can get lost in the general noise of life. At the end of the day we may have some vague awareness of positive experiences having been part of the day but they will be indistinct and just part of the general soup of experience. So, positivity challenges are a very good way to make sure we actually notice positive experiences when they happen. And that noticing will mean the positive experiences also have more of an impact upon us - they will actually feel more positive!

What does gratitude about the good things in our live bring to us?

Gratitude is a very important emotion and studies have shown that practising gratitude is very good for us. It means we feel more connected to others as well, and connection is also very good for us. We can feel isolated from others, when, in reality, every moment of every day we are deeply interconnected with the world around us. If I express gratitude to you, then you will feel valued and your positivity will increase. This means you will affect the people you come into contact with in a more positive way. And they will, in turn, be more positive and affect the people they come into contact with. And so the world is changed. There is the saying "change your mind, change the world" and this is how it works. Each moment of gratitude ripples out and changes the world.

Can being positive genuinely affect our happiness levels?

Positivity and happiness are very closely linked. Myriad studies show that being positive makes us more happy, and being happier makes us more positive. Perhaps you could say they are like two sides of a coin. Being more positive as an action leads to happiness as a feeling. You can't really have one without the other. And they are of course mutually reinforcing - happiness leads to more positive action which leads to more happiness. When positivity becomes a habit then happiness becomes a habit.