A study by Lancaster University showed that how people interpret everyday experience affects their behaviour and hence mood.

The research "Response styles, bipolar risk and mood in students: The Behaviours Checklist"published in Psychology and Psychotherapy: Theory, Research & Practice is by Dr Alyson Dodd, Claire Fisk and Dr Alan Collins.

They asked students to complete a Behaviours Checklist, which assessed goal-focused ‘ascent’ and ‘descent’ behaviours. Ascent behaviours include taking on more and risk-taking, whereas descent behaviours include withdrawing from other people and mulling over things. This was completed alongside measures of beliefs people have about how they are feeling, response styles to positive and negative mood, mania, depression, and hypomanic personality (bipolar risk).

They found that positive thoughts like “I will excel in whatever I’m doing” or negative like “I’m going to have a breakdown” influence mood in a way in which a more neutral thought  such as “I have a lot on and need to wind down” does not.

Dr Dodd said: “These appraisals trigger attempts to control or enhance internal states, known as ascent and descent behaviours, which drive mood and activation levels upwards and downwards respectively.”

The resulting behaviours further worsens their mood.

“These goal-focused behaviours are ways in which people respond directly to appraisals of their internal states, in order to regulate their mood. However, they are maladaptive coping strategies such that they disrupt effective mood regulation.”

The study found that both thoughts and ascent behaviours predicted bipolar risk, characterised by a hypomanic personality style, while negative thoughts and descent behaviours were associated with depression.