Replicating the 1991 Ulrich et al. study

Photo of Roger Ulrich

The landmark 1991 study by Roger Ulrich and colleagues ( ) —pivotal for its findings on the psychological benefits of contact with nature—confirmed the scientific status of stress reduction theory as a major paradigm in environmental psychology. Considering the major scientific and societal impacts of that study, it is important to determine whether these findings are empirically robust.

However, no direct replication of this study has yet been conducted. Follow-up research up to now has used different designs and methods than those in the original 1991 experiment and thus represent conceptual replications rather than close replications.

Therefore, the Center is collaborating part on a multi-laboratory global effort to replicate the 1991 Ulrich et al. study. In total, 11 labs from the Netherlands, UK, USA, and Sweden are collaborating, following identical protocols and using identical research materials and equipment. Like the original study, participants will have stress induced by way of watching a stressful video, after which they will be exposed to footage of different natural and urban environments. Various physiological measurements, such as cardiovascular activity, will be used to measure participants’ stress levels. While the methods used will remain faithful to the original study, the research teams will take advantage of advanced physiological monitoring technology to yield even more precise and insightful results.

For more information, contact Jenny Roe ( or Chris Neale (