By Emma Young

Are you an evening person — an owl? Or a morning person — a lark? No end of studies have reported variations in the functioning of people who like to wake and go to bed late, versus those who are early to bed and early to rise. And now a new study, published in PLoS One, has found links between our “chronotype” and the way we handle emotions, reflect on our thoughts and feelings, and assert ourselves. Overall, owls do worse. And this, argues Juan Manuel Antúnez at the University of Malaga, Spain, could help to explain links between being an owl and poorer psychological well-being.

Antúnez recruited 2,283 healthy Spanish men and women, aged 18-60 years, to complete a series of online questionnaires. First, their chronotype was assessed. This revealed that about 28% were owls, about 23% were larks, and the rest were neither. (This is similar to the estimated spread in the general population, with about 20% of us falling into each of the extreme groups and the remaining 60% in the middle.)

The participants also completed a questionnaire that explored their use of two different strategies for emotional regulation: “cognitive reappraisal”, which involves reframing a stressful situation to lessen its emotional impact and is related to greater well-being; and emotion suppression, which is maladaptive and is related to psychological problems like depression.

Another scale assessed participants’ meta-cognitions — the way they think about their thoughts and feelings. This scale included measures of maladaptive thought processes about feelings (for example, thinking that worry is useful for avoiding future problems) and thoughts (such as: “I should be controlling my thoughts all of the time” and “I am constantly aware of my thinking”).

The final measure asked the participants to report their own level of assertiveness — their tendency to (non-aggressively) affirm a right or a point of view.

The responses showed that chronotype was indeed related to these measures. The closer a participant was to the lark extreme, the more likely they were to use (beneficial) cognitive reappraisal to regulate their emotions. Those who were closer to the owl extreme were more likely to use suppression, however. This strategy has been related to all kinds of problems, including depression and decreased well-being, self-esteem, and social functioning.

Owls also scored highest for maladaptive ways of thinking about their thoughts and feelings. And they reported the lowest levels of assertiveness, while larks reported the highest. Assertiveness is a core skill for well-being, Antúnez notes, so could protect against psychological problems.

These results held even after controlling for gender and age-related differences. And for all the measures, those with an intermediate chronotype — who were neither owl nor lark — scored in the middle zone.

Because, biologically-speaking, owls only “wake up” later in the day, after normal school and work start times, they are out of sync with most countries’ daily routines. This “social jetlag” has been linked to greater fatigue. Perhaps that fatigue drives the poorer owl results on the measures in his study, Antúnez suggests. But, as he says, studies that follow people over time will be required to explore this.

Still, “although future longitudinal studies are needed,” he writes, “[the] results emphasize evening-type as a risk factor for the development of psychological disturbances and morning-type as a protective factor against those.”

– Circadian typology is related to emotion regulation, metacognitive beliefs and assertiveness in healthy adults

Emma Young (@EmmaELYoung) is a staff writer at BPS Research Digest