Interventions aiming to enhance cognitive functions (e.g., computerized cognitive training and non-invasive brain stimulation) are increasingly widespread for the treatment and prevention of cognitive decline. Drawing on the allure of neuroplasticity, such programs comprise a multi-billion dollar industry catering to researchers, clinicians, and individual consumers. Nevertheless, cognitive enhancement interventions remain highly controversial due to uncertainty regarding their mechanisms of action. A major limitation in cognitive enhancement research and practice is the failure to account for expectations of outcomes, which can influence the degree to which participants improve over an intervention (i.e., the placebo effect). Here, we sought to evaluate the psychometric properties of the Expectation Assessment Scale (EAS), a questionnaire we created to measure the perceived effectiveness of cognitive enhancement interventions. We delivered a web-based version of the EAS probing expectations of either computerized cognitive training or non-invasive brain stimulation. We assessed uni-dimensionality of the EAS using principal component analysis and assessed item properties with a graded item response model. Responses on the EAS suggest good validity based on internal structure, across all subscales and for both computerized cognitive training and non-invasive brain stimulation. The EAS can serve as a reliable, valid, and easily incorporated tool to assess the validity of cognitive enhancement interventions, while accounting for expectations of intervention outcomes. Assessing expectations before, during, and after cognitive enhancement interventions will likely prove useful in future studies.
展开▼
