Feeling blue can help some people to focus, manage their time and better prioritise tasks, research suggests.
In fact, researchers found being in a good mood may hamper time-keeping and organisational skills.
However, this was only true for extroverts - introverts ground to a halt when they felt gloomy.
The study, carried out by Tara McAuley, a psychology professor at the University of Waterloo in Canada, and Martyn Gabel, a PhD candidate; explored how 95 people coped with demands and stresses daily, depending on their mood.
Researchers focused on emotional reactivity - the sensitivity, intensity and duration of emotional responses associated with our mood. These are the defining factors that influence our ability to carry out tasks.
They categorised the group in terms of emotional reactivity - high-reactive people and low-reactive people.
High-reactive people (extroverts) have rapid, intense, and enduring emotional responses, while low-reactive people (introverts) are more relaxed.
In the research, extroverts performed better on executive function tasks when they were in a bad mood.
Meanwhile, low-reactive people showed the opposite effect: their abilities would grind to a halt when they were in a bad mood.
"Our results show there are some people for whom a bad mood may actually hone the kind of thinking skills that are important for everyday life," said McAuley.
"We know that emotional reactivity differs from person to person starting at a very early age and that these individual differences have implications for mental health later in development."