Number Letter Task

Alternate Names: Category Switch Task

FREE for use with an Inquisit Lab or Inquisit Web license.

Available Test Forms

Number Letter Task

A task switching paradigm in which participants must switch in a predictable fashion between categorizing letters or numbers as described by Miyake et al (2000).
Duration: 8 minutes
(Requires Inquisit Lab)
(Run with Inquisit Web)
Last Updated


Google ScholarSearch Google Scholar for peer-reviewed, published research using the Inquisit Number Letter Task.

Rogers, R. D., & Monsell, S. (1995). The costs of a predictable switch between simple cognitive tasks. Journal of Experimental Psychology: General, 124, 207–231.

Miyake, A., Friedman, N. P., Emerson, M. J., Witzki, A. H., Howerter, A., & Wager, T. D. (2000). The unity and diversity of executive functions and their contributions to complex “frontal lobe” tasks: A latent variable analysis. Cognitive Psychology, 41, 49–100.