who identify themselves as dog lovers tend to be more extroverted, while those who consider themselves cat people tend to be more introverted.
Plenty of psychological and mental health studies have demonstrated that certain forms of psychotherapy or medication treatment can benefit a range of mental states such as depressive episodes, panic attacks, or psychotic breaks. However, relatively few studies have targeted stable personality traits like conscientiousness or agreeableness. The researchers at the University of Illinois included only well-controlled investigations that specifically focused on measures of personality as outcomes of the interventions.
They systematically searched for the best-controlled studies that asked whether different interventions changed personality. The scientists searched for not only studies of therapies involving mental health professionals but self-help strategies as well. They wanted to include investigations and interventions that used control groups (i.e., volunteers who received no interventions at all) because patients often respond well to an inactive placebo treatment or by simply getting on a waiting list to receive a treatment. Those nonspecific influences on personality change needed to be factored out of the equation.
After an extensive search, they identified more than 200 studies that were of high enough quality to include in the meta-analysis. Each of the studies contained enough subjects to draw meaningful conclusions. And they all assessed one or more of the Big Five personality categories as outcome measures.
The number of volunteers totaled more than 20,000. Study subjects were mostly women (63 percent) and ranged in age from 19 to 73 years (on average, 36 years). Although personality change was the focus of the new meta-analysis, many of the research subjects were being treated for other mental conditions such as anxiety, depression, or substance abuse, while others had no specific mental disorder during the course of the study. Interventions also varied from medication treatments to various forms of psychotherapy and self-help approaches. Many of the interventions consisted of one-on-one therapies, while others involved group treatments or do-it-yourself methods.
Types of Interventions That Can Change Personality
• Cognitive behavioral therapy
• Mindfulness intervention
• Psychoanalytic/psychodynamic therapy
• Psychopharmacological treatment
• Relaxation training
• Social skill training
• Supportive psychotherapy
Because the various studies and types of interventions differed, the researchers needed to use a measure that would level the playing field in order to make their comparisons. They employed a statistical calculation known as the effect size to compare the benefits of all the various interventions. The effect size is essentially a number from 0 to 1 that indicates how much more effective a treatment is in a group of subjects when compared to a control group receiving placebo or no treatment at all. An effect size of 0.2 or less is considered small; the 0.3 to 0.5 range is thought of as medium; and anything at 0.6 or above is categorized as a large effect.
When the scientists systematically pooled all the results from this large meta-analysis, they drew a remarkable conclusion: both clinical (involving treatment from a mental health professional) and nonclinical self-help interventions (such as internet-based cognitive therapy or meditation) resulted in positive improvements in personality traits over a relatively brief period of time. Also, for the subjects who were followed a year or more after the treatment was completed, researchers found that the personality benefits resulting from the interventions were sustained.
The type of therapy didn’t seem to matter much when it came to improving personality traits in the subjects. Supportive psychotherapy, psychodynamic therapy, and cognitive behavior therapy demonstrated comparable levels of benefits, while hospitalization and psychopharmacology were only slightly less effective. Whether or not the research volunteers were being treated for depression, anxiety, or no particular disorder at all also had no influence on the results: personality traits consistently improved in the full range of people who were studied.
Some personality traits were more sensitive to treatment than were others. The greatest personality changes were observed for emotional stability followed by extraversion, agreeableness, conscientiousness, and openness.
How Fast Can Change Happen?
Professor Roberts and his colleagues assumed that very short interventions would not do much to change personality—they expected that one hour, one day, or one week of intervention couldn’t budge the long-term dispositions of the study subjects—so they also included studies that involved long-term therapies lasting many months.
To determine how long someone has to continue an intervention like therapy before it has a positive effect on personality, the researchers plotted each treatment’s degree of impact according to its duration. When they charted the effect size versus the duration of a treatment, another unexpected discovery was revealed: Most positive changes in personality were achieved within the first month of therapy. After that, the rate of change leveled off and the benefits plateaued.
Additional treatment didn’t provide any incremental improvement, but the original personality benefits achieved during the first 30 days remained stable and continued long after the treatment ended. The graph below shows the increase from neuroticism to emotional stability according to the number of weeks in treatment.
The surprising conclusion from this science is clear: We can change our personalities if we choose to, and meaningful change can be achieved as quickly as 30 days. Also, a variety of self-help therapies work, so meaningful personality improvements don’t necessarily require the help of a trained professional.
Your Personality Impacts Your Life
Some individuals readily accept who they are and how their life is going, good or bad. They have no desire or drive to change anything about themselves, especially their personality. Many people, however, feel that one or more of their character traits are holding them back—affecting their relationships, careers, and all-around life satisfaction. If you are someone who wishes to change, there is good reason to do so. Compelling scientific evidence indicates that your personality predicts many important outcomes in your life, including your physical health, success in relationships, and financial security.
Your personality traits also influence your life-span expectancy. Extroverts who tend to be friendlier and more socially connected enjoy greater longevity than introverts. People who are more neurotic have a shorter life expectancy than do more emotionally stable individuals. A large British study showed that cardiovascular illnesses contributed to the increased risk of death in neurotic people. Less conscientious people don’t live as long as those who are more conscientious, and it’s not surprising that those prone to taking risks may live more exciting lives, but on average their life-spans are shorter.
Your brain health and risk for several age-related illnesses can be affected by your personality style. Developing memory loss is one of the greatest concerns that people have as they age, and when that memory loss interferes with an individual’s independence, it is called dementia. We know that healthy lifestyle strategies—exercising regularly, eating right, managing stress, and remaining social—can reduce the risk of dementia, but your personality style has an influence as well. Investigators at the
