When it comes to managing our wellbeing, we're told to count our blessings. Self-help books swear by the practice -- and increasingly, so does science.
So how does gratitude actually help us?
Gratitude is a powerful yet unusual emotional state and one that continues to attract investigation.
Ask somebody about their life's work. It's the quality of their social relationships and the purposefulness of their activity through which they derive satisfaction.
"Psychologists and neuroscientists love to break down these kinds of constructs to differentiate them and describe the emotional states that go with them," Ian Hickie, Professor of Psychiatry and co-director of the Sydney Brain and Mind Centre told The Huffington Post Australia.
"With modern brain imaging techniques, we can see how the brain whizzes around whilst we experience these states and analyse them. What I think is more important is how humans are interacting... and that's where the conversation is heading."
Let's take a few strides back.
Put simply, gratitude is a state of being thankful or a readiness to show appreciation for and to return kindness. This can arise following help from others but also as a habitual focusing on the positive aspects of one's life.
According to Professor Hickie, it is built into our social behaviour.
"Humans are not individual animals -- we're social beings. If we do something that is good for us -- or good for the group -- and we experience an emotion that is positive, that emotion reinforces the behaviour and makes us more likely to do it again," Hickie said.
One of the most positive emotions that humans experience is feeling good. We all, for the state of our wellbeing, rely on those positive emotional states.
"In evolutionary terms, there is a great deal of interest into what those social behaviours are and what are the emotions that reinforce them. One of those is gratitude: the idea that if someone does something for you, you feel pleasure, and an instinct in some way to return to the favour."
Gratitude expression and the brain
There are countless studies that show performing simple gratitude exercises can bring a range of benefits including increased wellbeing and reduced depression. And then, more recently, there are those that use brain-scanning to help us understand these effect of these on brain activity.
"Most of the evidence that we have show that these strategies offer a small but significant effect, and that has something to do with pro-social behaviours that are tied to them," Hickie said.
Professor Hickie is internationally renowned for his research into clinical psychiatry that in part focuses on the use of neuro-imaging to understand the cause of depressive disorders.
"There has always been a school of positive psychological therapy in depression that encourages experiences that will precipitate or re-engage positive emotional states," Hickie said.
His interest lies in the return to focus on social cognition and 'social hormones' or neurochemicals.
What is happening in neurochemistry is we are trying to understand how these chemicals operate in humans in relation to social behaviours.
Often referred to as the cuddle hormone, oxytocin is released by mothers during childbirth and breastfeeding. Animals will reject their offspring when the release of oxytocin is being blocked.
"These are 'feel good' hormones which are not simple hits of hedonistic pleasure. They are associated with a warm positive emotion and they are only elected in social interaction," he said.
"There is a great deal of interest around whether the oxytocin hormones are relevant to a whole range of psychological states -- both in a positive sense and a therapeutic one.
"We're now asking, can we use this in certain situations? Only recently has this work translated to humans in a serious way."
Common behaviours tied to depressive disorders:
1. Withdrawal from social interactions
"In abnormal states like depression, people find social situations that require a great deal of social awareness of what is going on in social groups. When people are depressed, they tend not to function at that level so they withdraw from those interactions and their key relationships," Hickie said.
"This is associated with a loss of these positive feedback loops and reinfroces a vicious cycle."
2. Internal preoccupation
"This comes down to ignoring, misinterpreting or failing to recognise the good things that are happening around you. You're preoccupied with your internal world," Hickie said.
"The exercise of both doing positive things but also recording when good things happening to you is part of a cognitive therapy approach which is to try to maintain a balanced view of what is actually happening."
The pitfalls of positive psychology
Discussion around gratitude is part of a wave of research falling under the branch of psychology known as 'positive psychology'. It is one that continues to divide experts based on the deeply embedded premise that 'happiness heals'.
According to Professor Hickie, positive psychology has taken both steps forwards and back.
"Like everything, there has been a commodification of it that I think is unhelpful as distinct from the more profound concept that lies behind it: wellbeing," Hickie said.
Wellbeing is not a state of happiness.
"There's a misunderstanding that we just promote happiness and this just isn't the case. I have real problems with the notion of happiness as an individual commodity in isolation -- I'm much more attracted to the notion of wellbeing," Hickie said.
"Most people's sense of wellbeing is tied up in these pro-social behaviours and being engaged with their world. It isn't a constant emotional high.
"It's all of these social behaviours that elevate gratitude that I would argue are much more important in keeping groups functioning."
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