In this dissertation, we wanted to review the stability of the Big Five personality traits in relation to life events that might cause change. This topic came to our interest because few articles had tried to bring a consensus on when such changes might happen and whether they appear under specific circumstances. The dissertation therefore targeted to determine the influence of exercise, body weight, ecstasy, mental illnesses, diseases and traumatic experiences on the Big Five personality traits over the lifetime.
The Five-factor model of Costa & McCrae (1992) includes neuroticism, extraversion, openness to experience, conscientiousness and agreeableness, often called OCEAN in short. Neuroticism is the emotional stability aspect of personality whereas extraversion refers to social vitality and affiliation. Openness to experience is being curious and open-minded, agreeableness is compassion and friendliness to others. Conscientiousness refers to self-discipline.
Costa and McCrae (1992) understands personality in form of traits that become stable at 30 years of age. A trait is a pattern of behavior that corresponds more or less to a set personality in any given situation. Contrary to a state, a trait is considered stable over time and could be used to predict future behavior. In modern psychology, research on personality has become a widespread domain that targets areas such as child development, personal coping, well-being and self-esteem. There are two main reasons that personality research has become increasingly popular: 1) it could allow a prediction of criminal behavior, a clarification of recruitment issues and a prediction of addictions and 2) it could facilitate an early identification and prevention of many kinds of human suffering (i.e. mood disorders, suicide).
The two founding authors believe that personality traits are rooted in biological factors which are only marginally (if anything) influenced by environmental factors. However, twin studies have shown that 60-65 % of the variance observed in personality cannot be accounted for by genetic factors. Other similar studies have shown that personality is mostly influenced by the environment outside the family (i.e. not shared with siblings). Unfortunately, this approach cannot give us clear answers as to which environmental factors are liable to influence personality, thus it is necessary to look at changes across the lifespan and in response to specific events.
If looking at how personality traits evolve for an individual over time, the curve is neither linear nor stable. This is one of the most important evidence that personality does not seem to settle at the age of 30, but rather continues to change subtly at all ages and especially between the age of 20 and 40. Also in this field there are many discrepancies in between studies reporting different findings. It is therefore important to note that although both a certain stability and evolution have been found, it could be that the environment impacts individual differences in stability over time. Evidence was therefore drawn from studies that had looked at personality change in relation to health, poverty, work situation, illnesses and traumatic experiences. Here is a short summary of what was found:
One large study by Sutin et al. (2013) drew on data from a 10-year-long study on weight gain and personality. With almost 2000 participants, they showed that increased weight gain over this period was associated with an increased impulsivity. Similar, a study by Brown et al. (1994) found that females that followed an exercise program decreased in measures of neuroticism. Unfortunately, these two studies did not include the same parameters. We therefore cannot conclude that while controlling for exercise or weight gain / loss the results would be the same.
Looking at drug use, the drug 3,4 Methylenedioxymethamphetamine (MDMA) or ecstasy is the most commonly studied. Common side effects of taking this drug is mood disturbances and reduced cognitive abilities (Fox, Parrott & Turner, 2001). A unique study by Morgan (1998) showed on a small sample of ecstasy users versus non-users that the former had higher impulsivity and one facet of neuroticism (anger-hostility). However, there are still many limitations with research on drug use because it is very difficult to find mono-drug users and selection effects will likely influence the results (people higher in impulsivity are more likely to take drugs).
Furthermore, we saw that for children at the ages between 3 and 16 growing up in poverty had a negative evolution in personality traits even when controlling for maternal education level, family income, and support in the family environment. Looking at a more positive change, we saw that people between the ages 16 and 70 that choose to commit to a relationship showed decreases in neuroticism and increases in extraversion, conscientiousness and self-esteem (Neyer & Lenhart, 2007; Schollen & Diener, 2006). A small negative effect was seen for adverse relationships as well, however it importantly depends on how it is perceived by the person. If an adverse event is perceived to be more difficult by the person, he or she is more likely to be scarred by it (Simms & Bock, 2012).
Moreover, we could see some slight changes in personality when going to university and when getting a new job. This was especially true for those satisfied with their careers who most likely identified more with their job. Also changes in personality on a day-to-day basis was observed Judge, Simon, Hurst and Kelley (2013).
The correlation between “negative” personality traits and illnesses was noted for some mental illnesses (i.e. anxiety disorder, depressive disorder) but not in medical illnesses (i.e. coronary heart disease, irritable bowel disease). Further, self-reported extreme adverse events could, in retrospect, predict greater neuroticism and decreased agreeableness. However, in general, there are not many studies controlling for the person’s pre-trauma personality.
We have demonstrated that Big five personality traits can be affected by body weight, exercise, ecstasy, mental illnesses, diseases and traumatic experiences. So, even if a trait is considered stable through the lifespan, the environment impacts individual differences in stability over time. We note that a lot of studies focus on negative personality traits such as impulsivity and lower neuroticism. In a perceptive of prevention, furthers studies should investigate what kind of behavior can positively affect personality, like Brown et al. in 1994.
(Written by Ramona and Pierre)
References:
Brown, D., Wang, Y., Ward A., Ebbeling, C., Fortlage L., Puleo, E., Benson, H., & Rippie, J. (1994). Chronic psychological effects of exercise and exercise plus cognitive strategies. Medicine and Science in Sports and Exercise, 27, 765 – 775.
Costa, P. T., & McCrae, R (1992). Four ways five factors are basic. Personality and Individual Differences, 13, 653 – 665.
Fox, H., Parrott, A., & Turner, J. (2001). Ecstasy use: Cognitive deficits related to dosage rather than self-reported problematic use of the drug. Journal of Psychopharmacology, 15, 273 – 281.
Judge, T. A., Simon, L.S., Hurst, C., & Kelley, K. (2013). What I Experienced Yesterday Is Who I Am Today: Relationship of Work Motivations and Behaviors to Within-Individual Variation in the Five-Factor Model of Personality. The Journal of applied psychology, PMID: 24099348.
Morgan, M. (1998). Recreational use of ”Ecstasy” (MDMA) is associated with elevated impulsivity. Neuropsychopharmacology, 19, 252 – 264.
Neyer, F. J., & Lenhart, J. (2007). Relationships matter in personality development: Evidence from an 8-year longitudinal study across young adulthood. Journal of Personality, Journal of Personality, 75, 535–568.
Schollon, C.N., & Diener, E. (2006). Love, work, and changes in extraversion and neuroticism over time. Journal of Personality and Social Psychology, 91, 1152 – 1165.
Simms, K. and S. Bock, 2012. The explanatory power of adverse relationship experiences in predicting neuroticism. Curr. Res. Psychol., 3: 43-48.
Sutin, A., Costa, P. T., Chan, W., Milaneschi, Y., Eaton, W., Zonderman, A., Ferrucci, L., & Terracciano, A. (2013). I know not to, but I can’t help it: Weight gain and changes in impulsivity related personality traits. Psychological Science, 24, 1323 – 1328.
