Intra-Person Dynamics Across the Lifespan

The overarching objective of this project is to test theories and explore research designs that articulate human development across different timescales, levels of analysis, and functional domains. The project is based on the premise that a comprehensive understanding of behavioral development across the lifespan requires a person-oriented, multivariate, and longitudinal approach. Only a high density of observations within individuals allows researchers to distinguish among different forms and functions of variability and change. Such high-density data offer great opportunities, but also pose new theoretical and methodological challenges. The project meets these challenges by a strong emphasis on methodology, understood as the productive interplay between substantive research and method development. Regarding the latter, the project collaborates closely with the Formal Methods project.


Gruppe Intra Person Dynamics
© MPI fuer Bildungsforschung

Research Foci

Relationships Between Intraindividual Variability and Change Across Different Domains and Timescales

Investigations with data from the COGITO study (see below) address intraindividual variability and change at timescales that range from moment-to-moment variability in reaction times, day-to-day fluctuations in cognitive performance, to changes over years—like the long-term effects of COGITO’s extensive cognitive training on cognitive abilities and personality traits. Analyses focus on the ways in which constructs are linked within persons over time, such as couplings between day-to-day fluctuations in positive affect and working memory performance.

Using Continuous Time and Moderated Time-Series Models to Analyze Human Development Across Different Timescales and Contexts

While most psychological processes develop continuously over time, we need to rely on discrete measurement occasions to infer them. The goal is thus to reconstruct the mechanisms underlying a continuously unfolding process, such as human development, based on few discrete snapshots in time. Continuous-time models are well suited to achieve this goal. In contrast to popular discrete-time methods, continuous-time models link discrete-time observations to underlying continuous-time parameters by stochastic differential equations. This may not only remove bias due to variability in sampling time and improve comparability across different research designs, it also yields valuable information about the nature of change.

Integrating Within-Person and Between-Person Information in the Search for Causal Mechanisms

Most empirical research in psychology is based on analyzing between-person variation. In contrast, most applied psychology is concerned with variation within individuals. In addition, the mechanisms specified by psychological theories generally operate within, rather than across, individuals. This disconnect between research practice, applied demands, and psychological theories constitutes a major threat to the conceptual integrity of the field. This project is working on reconciling these extreme positions, both conceptually and methodologically.


Logo of the COGITO-Study

In the COGITO study, 101 younger adults (20–31 years of age) and 103 older adults (65–80 years of age) participated in 100 daily sessions in which they worked on cognitive tasks measuring perceptual speed, episodic memory, and working memory, as well as various self-report measures (see Schmiedek, Lövdén, & Lindenberger, 2010). All participants completed pretests and posttests with baseline measures of cognitive abilities and transfer tasks for the practiced abilities. Brain-related measures were taken from subsamples of the group, including structural magnetic resonance imaging (MRI), functional MRI, and electroencephalo-graphic (EEG) recordings. A central goal of the COGITO study was the comparison of between-person and within-person structures of cognitive abilities. Further, the COGITO study qualifies as a cognitive training study of unusually high dosage and long duration because of its 100 sessions of challenging cognitive tasks.

Recent Publications

Lydon-Staley, D. M., Ram, N., Brose, A., & Schmiedek, F. (in press). Reduced impact of alcohol use on next-day tiredness in older relative to younger adults: A role for sleep duration. Psychology and Aging.

Mueller, S., Wagner, J., Voelkle, M. C., Smith, J., & Gerstorf, D. (in press). The interplay of personality and functional health in old and very old age: Dynamic within-person interrelations across up to 13 years. Journal of Personality and Social Psychology.

van Montfort, K., Oud, J., & Voelkle, M. C. (Eds.). (in press). Continuous time modeling in the behavioral and related sciences. New York: Springer.

Adolf, J. K., Voelkle, M. C., Brose, A., & Schmiedek, F. (2017). Capturing context-related change in emotional dynamics via fixed moderated time series analysis. Multivariate Behavioral Research, 52, 499–531. doi: 10.1080/00273171.2017.1321978

Sander, J., Schmiedek, F., Brose, A., Wagner, G. G., & Specht, J. (2017). Long-term effects of an extensive cognitive training on personality development. Journal of Personality, 85, 454–463. doi: 10.1111/jopy.12252

Voelkle, M. C., & Adolf, J. (2017). History of longitudinal statistical analyses. In N. A. Pachana (Ed.), Encyclopedia of geropsychology (pp. 1094–1102). New York: Springer.


Manuel C. Voelkle (adjunct researcher)

Annette Brose (adjunct researcher)
Ulman Lindenberger
Florian Schmiedek (adjunct researcher)

Janne Adolf
Charles C. Driver (postdoctoral fellows)

Key References

Brose, A., Schmiedek, F., Koval, P., & Kuppens, P. (2015). Emotional inertia contributes to depressive symptoms beyond perseverative thinking. Cognition and Emotion, 29, 527–538. doi: 10.1080/02699931.2014.916252

Driver, C. C., Oud, J. H. L., & Voelkle, M. C. (2017). Continuous time structural equation modeling with R package ctsem. Journal of Statistical Software, 77:5. doi: 10.18637/jss.v077.i05

Hertzog, C., Lövdén, M., Lindenberger, U., & Schmiedek, F. (2017). Age differences in coupling of intraindividual variability in mnemonic strategies and practice-related associative recall improvements. Psychology and Aging, 32, 557–571. doi: 10.1037/ pag0000177

Schmiedek, F., Lövdén, M., & Lindenberger, U. (2010). Hundred days of cognitive training enhance broad cognitive abilities in adulthood: Findings from the COGITO study. Frontiers in Aging Neuroscience, 2:27. doi: 10.3389/fnagi.2010.00027

Voelkle, M. C., Brose, A., Schmiedek, F., & Lindenberger, U. (2014). Towards a unified framework for the study of between-person and within-person structures: Building a bridge between two research paradigms. Multivariate Behavioral Research, 49, 193–213. doi: 10.1080/ 00273171.2014.889593

COGITO Conference 2016

An international conference entitled "The COGITO Study: Looking at 100 Days Ten Years After“ took place in October 2016. Various world-leading behavioral scientists participated. More information can be found here.

Cover Programmheft
© Foto: David Ausserhofer

Lifespan Neural Dynamics Group

The Lifespan Neural Dynamics Group, headed by Douglas Garrett, began its work within this project and is now part of the Max Planck UCL Centre for Computational Psychiatry and Ageing Research. For more information, click here.

Lifespan Neural Dynamics Group
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