Situations shape personality, just as personality shapes situations

It's easy to think of ways that personality affects how we approach situations. But a new study looks at the other side of the coin: how situations alter our personality. This research suggests that while our personality at work has a stable, predictable quality, experience of meaningful events produces 'personality states' that deviate from our baseline traits.

Timothy Judge's team recruited 122 participants in full employment into this online study, measuring their general personality traits at the outset using a combination of scales that all focused on the 'Big 5' traits (extraversion, conscientiousness, openness to experience, agreeableness and neuroticism) that comprise our best understood model of personality. Over the next ten days, participants made daily recordings of their experiences at work, as well as rating personality states – how they saw themselves as being on that particular day – again using Big 5 scales. Participants were asked to make these daily entries as close to the end of the day as possible, and the online survey was only available for completion between 3 and 11pm.

Judge was interested in how personality states on one day are influenced by events on the previous day. Research suggests that the day is a meaningful unit for investigation, possibly because of the way sleep functions to consolidate experiences into learning; it also makes claims about causality more credible than looking at variables simultaneously. Here is a summary of the key findings: 

Engaging in helpful, proactive organisational citizenship behaviours led to higher next-day extraversion, openness to experience and agreeableness. Engaging in personal goalsetting was associated with higher next-day conscientiousness; and high levels of intrinsic motivation – e.g. "Today, I've not needed a reason to work; I've worked because I want to" – was related to next-day agreeableness, conscientiousness and openness. On the negative side,  work conflict on one day left participants in a heightened neurotic state the next.

Two things important to note. First personality state often influenced likelihood of next-day events: for instance, a higher state of openness was associated with more intrinsic motivation the following day. When you consider this, the data sounds a bit of a tangle – if motivation and openness climb for days, what's driving what? – but the analysis used specific technical controls to separate out the effects. And of course, if personality were having no effect on how we behave, it wouldn't be a very useful thing to measure in the first place. But it's pertinent that the effects of event on state tended to be stronger than the reverse.

Secondly, personality states were always strongly associated with personality traits. Who we are still has a consistent quality, it's just that we vary around this. As with previous research (eg on affect spin http://bps-occupational-digest.blogspot.de/2011/08/some-of-us-experience-bigger-emotional.html), it appears that we each differ in how much we vary from our baseline. This study suggests that higher variability in our personality states may be associated with higher levels of trait neuroticism, and an up-one-day, down-the-next volatility certainly fits that profile.

Understanding that personality isn't merely a static predisposition but involves interaction with the environment is a key part of 'whole trait theory,' an important advance in individual difference research. And it has practical applications: we often think about conscientious people as being those who tend to set goals. But it's empowering to flip it, and know that setting goals is part of what makes us conscientious. It helps us better understand virtuous cycles, where one good turn produces the state that can lead to another, and keeps us aware of the power of dynamics in a working environment.

Judge TA, Simon LS, 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

Further reading:
Fleeson, W. (2001). Toward a structure- and process-integrated view of personality: Traits as density distributions of states. Journal of Personality and Social Psychology, 80, 1011-1027.