People’s personalities can be changed with effort over time

People’s personalities can change with age, but research shows they can also be changed with effort too. It just takes quite a bit of time.

Listener (Noted): Dunedin Study head reveals how you can change your personality

Decades of self-help books, some of them even with a bit of science at their command, suggest we can, if we put our minds to it, cherry-pick at will from among the Myers-Briggs Type Indicator’s 16 personality types or change our attachment type from preoccupied avoidant to secure.

It turns out there’s some truth among the mumbo jumbo.

Central to the nature-versus-nurture debate is whether one’s personality is fixed or mutable, and the latest word is, it’s mutable – just not quickly. The world-leading longitudinal Dunedin Multidisciplinary Health & Development Study at the University of Otago has found that personality traits have a tendency to deepen as we get older, and they can be affected by life experiences.

After analysing data from a cohort of young adults at age 26, whom researchers have been tracking since birth, a landmark report from the study found work had an effect on personality.

A lot of notable research has been done as a part of the world-renowned Dunedin Study.

It found distinctive changes in personality traits between adolescence and entry into the workforce, and not always the expected ones. For instance, the much-vaunted “constraint” weighting, which measures how much self-control and conscientiousness an individual has – which is believed to be a strong precursor to a successful, well-adjusted life – was not as big a factor in affecting how people got on as young adults as their emotional maturity and outlook on life.

It was already known that people tend to become more self-disciplined and positive as they move from the teenage years into adulthood. But what the study has added to this picture is that a person’s work experiences can have a big effect on the extent and nature of those changes.

Many of us spend a big chunk of our lives at work, so it is not surprising that we can be affected by work experiences and work relationships.

The head of the “Dunedin Study” at the National Centre for Lifecourse Research, Professor Richie Poulton, says this does sound a bit obvious and there are “normative” factors in personality change, such as the effect of becoming independent, having to submit to work requirements, forming a long-term relationship and becoming a parent. Also, he says, we now know that brain development, particularly that which modifies impulsiveness, is not complete until about the age of 24. “I was still an adolescent at 26. A lot of people are, so that’s a factor here, too.”

But, Poulton says, the data’s confirmation that personality is not, as was once widely thought, unchanging is extremely reassuring. “Personality study is the field of how we deal with things and it’s helpful to know that it’s far more dynamic than we might have thought.”

This has welcome policy-formation implications, which, handily enough, Poulton is helping to shape as chief science adviser to the Ministry of Social Development, and to the Prime Minister in her role as Minister for Child Poverty Reduction.

The research has obvious implications for trying to break inter-generational cycles of poverty.

Poulton says the key time for positive change remains in early childhood, where individual temperaments can most easily be moulded to improve future well-being. Young children with a tendency to be aggressive or impulsive can be conditioned over time into more positive traits – not least because such change brings immediate benefits.

“The world rewards you when you have those positive traits, when you don’t hit people or act up or shout and you can share and communicate.”

The report says those who start life with a high score for “niceness”, meaning positive and pleasing interpersonal skills, such as sociability, did better younger and earned more.

There will obviously be exceptions, but it’s good to know that niceness is often rewarded by success in life.

Life’s difficulties only compound for people the further they get towards adulthood with negative traits such as anxiety, aggression and a sense of alienation still in the ascendancy. The study has found that those who had a higher proportion of these negative traits at 18 went on to have poorer work experiences. By 26, they had lower-prestige jobs, reported less satisfaction with their working lives and had trouble making ends meet.

“Alienated and hostile adolescents appear trapped in a self-fulfilling and vicious cycle,” says Poulton. “Their personality disposition leads them to work experiences that undermine their ability to make a successful and rewarding transition to the adult world.”

That also seems logical.

Poulton says the recent spate of self-help books on the subject of willpower are generally close to the mark in saying that long-established habits, manifestations of personality traits, can be changed – but not all at once and not quickly.

“You have to keep chipping, chipping, chipping away. And there’s the ‘nudge theory’ that your environment can encourage you towards positive behaviour and away from what you’re trying to change. But it does have to be a bit challenging, too, so you build resilience. And the other important thing is that, as your nana also said, ‘If you fall over [or] make a mistake, get up and try again.’ Mistakes, going two steps forward and one back, are inevitable. You have to keep chipping away.”

So positive personality change is possible, with time and effort.

I guess that negative change is also possible, depending on circumstances and who you associate with.