PhD student Nancy Tsai is first author of an article in Journal of Applied Research in Memory and Cognition: "(Un)Great Expectations: The Role of Placebo Effects in Cognitive Training." Co-authors are Martin Buschkuehl, Snigdha Kamarsu, Priti Shah, John Jonides, and Susanne Jaeggi.
A growing body of literature demonstrating the malleability of critical higher-order cognitive functions by means of targeted interventions has incited widespread scientific interest, most notably in the form of cognitive training programs. The results are mixed and a point of contention: It has been argued that gains observed in cognitive training are mainly due to placebo effects. To address this, we examined the effect of participant expectations on one type of cognitive training that has been central to the controversy, namely n-back training, by inducing beliefs about expected outcomes. Participants receiving n-back training showed improvements in non-trained n-back performance regardless of expectations, and furthermore, expectations for positive outcomes did not result in any significant gains in an active control group. Thus, there was no detectable expectancy effect in either direction as a function of the cognitive intervention used, suggesting that training-related improvements are unlikely due solely to a placebo effect.
Tsai, N., Buschkuehl, M., Kamarsu, S., Shah, P., Jonides, J., & Jaeggi, S. (2018), (Un)great expectations: The role of placebo effects in cognitive training. Journal of Applied Research in Memory and Cognition. https://doi.org/10.1016/j.jarmac.2018.06.001