Research suggests that even momentary mood changes can significantly increase the brain's response to pleasure in individuals with bipolar disorder.
Individuals with this mental condition, characterised by extreme shifts in moods and energy levels, are more susceptible to what researchers term as "mood bias." This phenomenon occurs when a person's good mood leads them to view everything more favourably, thus gaining momentum in their mood.
Liam Mason, co-lead author of the study published in the journal Biological Psychiatry Global Open Science and affiliated with University College London's Psychology and Language Sciences, explained, "Imagine going to a new restaurant for the first time. If you happen to be in a fantastic mood, you're likely to perceive the experience as being even better than it actually is."
The findings shed light on why individuals with bipolar disorder often find themselves caught in a "vicious cycle," where mood escalation can lead to taking bigger risks than usual, the researchers noted.
In the study, researchers scanned the brains of participants while they played a computerised version of the Roulette game. The study involved 21 participants with bipolar disorder and 21 without. During the game, participants made bets on which compartment of a revolving wheel a small ball would land in.
Using functional Magnetic Resonance Imaging (fMRI), the researchers tracked the participants' brain responses to winning and losing. They utilised computer models to measure how mood changes affected the "reward signals" in the brain within seconds. The results revealed heightened activity in the brain's anterior insula, a region associated with mood changes, in both groups of participants during the game.
