Jaap Denissen

Humboldt-University Berlin, Germany

www.psychology.hu-berlin.de/staff/1682036

What does your research focus on?

I am interested in longitudinal transactions between persons and situations. How do people change their behavior in response to situational demands, both in the short term (e.g., on a day-to-day level) and in the longer term (e.g., during an important life transition)? How do people differ in these responses? What effects do these differences have on important life outcomes, such as well-being and friendship formation?

What drew you to this line of research? Why is it exciting to you?

People tend to underestimate how different we are from each other. When we are born, we begin life with certain biological and genetic foundations, but we also change as a response to social demands and experiences. It is fun to watch people develop and change! It is also fascinating to see how people react to these emerging individual differences. For example, can they accept being different from each other and still be good friends? And do people have an accurate view of these individual differences in themselves and others? To me, these topics are truly fascinating because they touch existential questions about the value of self-insight and the importance of similarity.

Who were/are your mentors or psychological influences?

Dan McAdams has sparked a continuing fascination about the complexity and richness of personality, both with his research and his textbook on personality psychology that I read when I was a student. Moreover, Jens Asendorpf, my former PhD advisor, has taught me to always question the validity and boundaries of my knowledge.

To what do you attribute your success in the science?

Science is both a collective and individual enterprise, so it can be difficult to separate the two in figuring out what has contributed to a career. I definitely benefited from contacts and conversations with great colleagues and mentors. Also, I guess I always try to push the limits of my own knowledge and think outside of the box.

What’s your future research agenda?

Together with my colleague, Michael Dufner, I am trying to learn more about the consequences of self-insight. Is “knowing thyself” beneficial in terms of life satisfaction and niche selection? And what kinds of personality traits can explain that some people have more of it than others? In addition, with Wiebke Bleidorn, I am embarking on an in-depth investigation of what happens when people become parents. What kind of demands does this place on their self-regulation skills, and how do they cope with that? How does the experience of being a mom or a dad change the way we tell our life story to ourselves and others?

Any advice for even younger psychological scientists? What would you tell someone just now entering graduate school or getting their PhD?

Try to stay intrinsically motivated! If you think science focuses too much on external criteria (number of papers, grants, network connections), don’t turn your back on it but try to be different instead. Focus on the topics that really fascinate you instead of trying to adopt every methodological or conceptual fashion. This will give you the energy for hard work and creative thinking. Besides, it’s more fun that way.

What publication are you most proud of or feel has been most important to your career?

Selfhout, M., Denissen, J. Branje, S., & Meeus, W. (2009). In the eye of the beholder: perceived, actual, and peer-rated similarity in personality, communication, and friendship intensity during the acquaintanceship process. Journal of Personality and Social Psychology, 96, 1152-1165.

It’s a paper I co-authored with Maarten van Zalk (formerly Selfhout) in 2009 entitled “In the eye of the beholder: Perceived, actual, and peer-rated similarity in personality, communication, and friendship intensity during the acquaintanceship process.” It followed up on largely unsuccessful efforts to study the effects of personality similarity on communication during my dissertation. I am proud of this publication because I did not give up after initial disappointments, but instead tried harder to come up with a more informative study, which ended up getting published in my field’s flagship journal, JPSP.