Improving Methodological Standards in Behavioral Interventions for Cognitive Enhancement
There is substantial interest in the possibility that cognitive skills can be improved by dedicated behavioral training. Yet despite the large amount of work being conducted in this domain, there is not an explicit and widely agreed upon consensus around the best methodological practices. This document seeks to fill this gap. We start from the perspective that there are many types of studies that are important in this domain—e.g., feasibility, mechanistic, efficacy, and effectiveness. These studies have fundamentally different goals, and, as such, the best-practice methods to meet those goals will also differ. We thus make suggestions in topics ranging from the design and implementation of control groups, to reporting of results, to dissemination and communication, taking the perspective that the best practices are not necessarily uniform across all study types. We also explicitly recognize and discuss the fact that there are methodological issues around which we currently lack the theoretical and/or empirical foundation to determine best practices (e.g., as pertains to assessing participant expectations). For these, we suggest important routes forward, including greater interdisciplinary collaboration with individuals from domains that face related concerns. Our hope is that these recommendations will greatly increase the rate at which science in this domain advances.
KeywordsCognitive enhancement Behavioral intervention methodology
National Science Foundation (DRL-1641280) to Dr C. Shawn Green; Office of Naval Research grant to Dr. Daphne Bavelier.
Compliance with Ethical Standards
Conflict of Interest
The following authors have declared conflict(s) of interest. Bavelier is a founding partner and on the scientific advisory board of Akili Interactive, Boston; Vinogradov is a consultant for Posit Science Corp, Alkermes, Inc., and Mindstrong, Inc.; Ball owns stock in the Visual Awareness Research Group (formerly Visual Awareness, Inc.) and Posit Science, Inc., the companies that market the Useful Field of View Test and speed of processing training software (now the Double Decision exercise in BrainHQ), and is a member of the Posit Science Scientific Advisory Board; Gazzaley is a co-founder, scientific advisor, and BOD member for Akili Interactive Lab and has several patents filed at UCSF for video game enhancement technologies; Jaeggi has an indirect financial interest in the MIND Research Institute, Irvine, CA, whose interests are related to this work; Levi is a member of the Scientific Advisory Board of NovaSight; Morris is on the scientific advisory boards of Neurotrack and of the AARP Global Council on Brain Health; Nahum is a paid consultant for Posit Science; Panizzutti is the founder of NeuroForma LTDA, a company with a financial interest in computerized cognitive training; Seitz is a founder and stakeholder in Carrot Neurotechnology, a company that sells a vision brain game called ULTIMEYES. The other authors declare that they have no conflict of interest.
- Acosta, A., Adams, R.B., Jr., Albohn, D.N., Allard, E.S., Beek, T., Benning, S. D., … Zwaan, R. A. (2016). Registered replication report: Strack, Martin, & Stepper (1988). Perspectives on Psychological Science, 11(6), 917–928. doi: https://doi.org/10.1177/1745691616674458.
- Anguera, J.A., Boccanfuso, J., Rintoul, J.L., Al-Hashimi, O., Faraji, F., Janowich, J., … Gazzaley, A. (2013). Video game training enhances cognitive control in older adults. Nature, 501(7465), 97–101. doi: https://doi.org/10.1038/nature12486.
- Ball, K., Berch, D. B., Helmers, K. F., Jobe, J. B., Leveck, M. D., Marsiske, M., … Group, A. S. (2002). Effects of cognitive training interventions with older adults: a randomized controlled trial. JAMA, 288(18), 2271–2281.Google Scholar
- Baniqued, P., Allen, C.M., Kranz, M.B., Johnson, K., Sipolins, A., Dickens, C., …, Kramer, A.F. (2015). Working memory, reasoning, and task switching training: transfer effects, limitations, and great expectations?. PLoS One. doi: https://doi.org/10.1371/journal.pone.0142169.
- Barry, A. E., Szucs, L. E., Reyes, J. V., Ji, Q., Wilson, K. L., & Thompson, B. (2016). Failure to report effect sizes: the handling of quantitative results in published health education and behavior research. Health Education & Behavior, 43(5), 518–527. https://doi.org/10.1177/1090198116669521.CrossRefGoogle Scholar
- Beaumont, J. L., Havlik, R., Cook, K. F., Hays, R. D., Wallner-Allen, K., Korper, S. P., …, Gershon, R. (2013). Norming plans for the NIH toolbox. Neurology, 80(11 Suppl 3), S87–92. doi: https://doi.org/10.1212/WNL.0b013e3182872e70.
- Biagianti, B., & Vinogradov, S. (2013). Computerized cognitive training targeting brain plasticity in schizophrenia. Progress in Brain Research, 207, 301–326. https://doi.org/10.1016/B978-0-444-63327-9.00011-4.CrossRefPubMedGoogle Scholar
- Boot, W. R., Simons, D. J., Stothart, C., & Stutts, C. (2013). The pervasive problem with placebos in psychology: why active control groups are not sufficient to rule out placebo effects. Perspectives on Psychological Science, 8(4), 445–454. https://doi.org/10.1177/1745691613491271.CrossRefPubMedGoogle Scholar
- Colzato, L. S., van den Wildenberg, W. P., & Hommel, B. (2014). Cognitive control and the COMT Val(1)(5)(8)Met polymorphism: genetic modulation of videogame training and transfer to task-switching efficiency. Psychological Research, 78(5), 670–678. https://doi.org/10.1007/s00426-013-0514-8.CrossRefPubMedGoogle Scholar
- Diao, D., Wright, J. M., Cundiff, D. K., & Gueyffier, F. (2012). Pharmacotherapy for mild hypertension. Cochrane Database of Systematic Reviews(8). doi: https://doi.org/10.1002/14651858.CD006742.pub2.
- Dweck, C. (2006). Mindset: the new psychology of success. New York: Random House.Google Scholar
- Eldridge, S. M., Lancaster, G. A., Campbell, M. J., Thabane, L., Hopewell, S., Coleman, C. L., & Bond, C. M. (2016). Defining feasibility and pilot studies in preparation for randomised controlled trials: development of a conceptual framework. PLoS One, 11(3), e0150205. https://doi.org/10.1371/journal.pone.0150205.CrossRefPubMedPubMedCentralGoogle Scholar
- Erickson, K. I., Voss, M. W., Prakash, R. S., Basak, C., Szabo, A., Chaddock, L., et al. (2011). Exercise training increases size of hippocampus and improves memory. Proceedings of the National Academy of Sciences of the United States of America, 108(7), 3017–3022. https://doi.org/10.1073/pnas.1015950108.CrossRefPubMedPubMedCentralGoogle Scholar
- Fassler, M., Meissner, K., Kleijnen, J., Hrobjartsson, A., & Linde, K. (2015). A systematic review found no consistent difference in effect between more and less intensive placebo interventions. Journal of Clinical Epidemiology, 68(4), 442–451. https://doi.org/10.1016/j.jclinepi.2014.11.018.CrossRefPubMedGoogle Scholar
- FEDERAL TRADE COMMISSION, (2016) Plaintiff, V.. Lumos Labs, Inc., a corporation d/b/a Lumosity and Kunal Sarkar, and Michael Scanlon, Individually and as officers of LumoS Labs, Inc. Defendants. , No. Case No. 3:16-cv-00001-sk (United StateS DistricT Court for the Northern District of California, San Francisco Division.Google Scholar
- Hallock, H., Collins, D., Lampit, A., Deol, K., Fleming, J., & Valenzuela, M. (2016). Cognitive training for post-acute traumatic brain injury: a systematic review and meta-analysis. Frontiers in Human Neuroscience, 10, 537. https://doi.org/10.3389/fnhum.2016.00537.CrossRefPubMedPubMedCentralGoogle Scholar
- Health, N. I. o. (2014). Notice of Revised NIH Definition of “Clinical Trial”. (NOT-OD-15-015). Retrieved from https://grants.nih.gov/grants/guide/notice-files/NOT-OD-15-015.html. Accessed 1 Nov 2018.
- Hendershot, T., Pan, H., Haines, J., Harlan, W. R., Marazita, M. L., McCarty, C. A., …, Hamilton, C. M.. (2015). Using the PhenX toolkit to add standard measures to a study. Curr Protoc Hum Genet, 86, 1 21 21–17. https://doi.org/10.1002/0471142905.hg0121s86.
- Holtzer, R., Shuman, M., Mahoney, J. R., Lipton, R., & Verghese, J. (2011). Cognitive fatigue defined in the context of attention networks. Neuropsychology, Development, and Cognition. Section B, Aging, Neuropsychology and Cognition, 18(1), 108–128. https://doi.org/10.1080/13825585.2010.517826.CrossRefPubMedGoogle Scholar
- Howard, J. (2016). Do brain-training exercises really work? CNN. Retrieved from https://www.cnn.com/2016/10/20/health/brain-training-exercises/index.html. Accessed 1 Nov 2018.
- Hrobjartsson, A., Forfang, E., Haahr, M. T., Als-Nielsen, B., & Brorson, S. (2007). Blinded trials taken to the test: an analysis of randomized clinical trials that report tests for the success of blinding. International Journal of Epidemiology, 36(3), 654–663. https://doi.org/10.1093/ije/dym020.CrossRefPubMedGoogle Scholar
- Jones, R. N., Marsiske, M., Ball, K., Rebok, G., Willis, S. L., Morris, J. N., & Tennstedt, S. L. (2013). The ACTIVE cognitive training interventions and trajectories of performance among older adults. Journal of Aging and Health, 25(8 Suppl), 186S–208S. https://doi.org/10.1177/0898264312461938.CrossRefPubMedGoogle Scholar
- Kaptchuk, T. J., Friedlander, E., Kelley, J. M., Sanchez, M. N., Kokkotou, E., Singer, J. P., et al. (2010). Placebos without deception: a randomized controlled trial in irritable bowel syndrome. PLoS One, 5(12), e15591. https://doi.org/10.1371/journal.pone.0015591.CrossRefPubMedPubMedCentralGoogle Scholar
- Katz, B., Jaeggi, S. M., Buschkuehl, M., Shah, P., & Jonides, J. (2018). The effect of monetary compensation on cognitive training outcomes. Learning and Motivation, 63(77–90).Google Scholar
- Kramer, A. F., Larish, J., & Strayer, D. L. (1995). Training for attentional control in dual-task settings: a comparison of young and old adults. Journal of Experimental Psychology: Applied, 1, 50–76.Google Scholar
- Mayer, R. E. (Ed.). (2014). Computer games for learning: an evidence-based approach. Cambridge: MIT Press.Google Scholar
- Merzenich, M. M., Nahum, M., & Van Vleet, T. M. (2013). Neuroplasticity: introduction. Progress in Brain Research, 207, xxi–xxvi. https://doi.org/10.1016/B978-0-444-63327-9.10000-1.CrossRefPubMedGoogle Scholar
- Mohr, D. C., Schueller, S. M., Riley, W. T., Brown, C. H., Cuijpers, P., Duan, N., et al. (2015). Trials of intervention principles: evaluation methods for evolving behavioral intervention technologies. Journal of Medical Internet Research, 17(7), e166. https://doi.org/10.2196/jmir.4391.CrossRefPubMedPubMedCentralGoogle Scholar
- Nahum, M., Lee, H., & Merzenich, M. M. (2013). Principles of neuroplasticity-based rehabilitation. Progress in Brain Research, 207, 141–171. https://doi.org/10.1016/B978-0-444-63327-9.00009-6.CrossRefPubMedGoogle Scholar
- Nosek, B. A., Ebersole, C. R., DeHaven, A. C., & Mellor, D. T. (2017). The preregistration revolution. OSF Preprints. doi: https://doi.org/10.17605/OSF.IO/2DXU5.
- Onken, L. S., Carroll, K. M., Shoham, V., Cuthbert, B. N., & Riddle, M. (2014). Reenvisioning clinical science: unifying the discipline to improve the public health. Clinical Psychological Science: A Journal of the Association for Psychological Science, 2(1), 22–34. https://doi.org/10.1177/2167702613497932.CrossRefGoogle Scholar
- Owen, A. M., Hampshire, A., Grahn, J. A., Stenton, R., Dajani, S., Burns, A. S., … Ballard, C. G. (2010). Putting brain training to the test. Nature, 465(7299), 775–778.Google Scholar
- Pek, J., & Flora, D. B. (2017). Reporting effect sizes in original psychological research: a discussion and tutorial. Psychological Methods. doi: https://doi.org/10.1037/met0000126.
- Rebok, G. W., Ball, K., Guey, L. T., Jones, R. N., Kim, H. Y., King, J. W., … Group, A. S. (2014). Ten-year effects of the advanced cognitive training for independent and vital elderly cognitive training trial on cognition and everyday functioning in older adults. Journal of the American Geriatrics Society, 62(1), 16–24. doi: https://doi.org/10.1111/jgs.12607.
- Redick, T. S., Shipstead, Z., Harrison, T. L., Hicks, K. L., Fried, D. E., Hambrick, D. Z., … Engle, R. W. (2013). No evidence of intelligence improvement after working memory training: a randomized, placebo-controlled study. Journal of Experimental Psychology: General, 142(2), 359–379.Google Scholar
- Roberts, G., Quach, J., Spencer-Smith, M., Anderson, P. J., Gathercole, S., Gold, L., … Wake, M. (2016). Academic outcomes 2 years after working memory training for children with low working memory: a randomized clinical trial. JAMA Pediatrics, 170(5), e154568. doi: https://doi.org/10.1001/jamapediatrics.2015.4568.
- Ross, L. A., Edwards, J. D., O’Connor, M. L., Ball, K. K., Wadley, V. G., & Vance, D. E. (2016). The transfer of cognitive speed of processing training to older adults’ driving mobility across 5 years. The Journals of Gerontology. Series B, Psychological Sciences and Social Sciences, 71(1), 87–97. https://doi.org/10.1093/geronb/gbv022.CrossRefPubMedGoogle Scholar
- Rothbaum, B. O., Price, M., Jovanovic, T., Norrholm, S. D., Gerardi, M., Dunlop, B., … Ressler, K. J. (2014). A randomized, double-blind evaluation of D-cycloserine or alprazolam combined with virtual reality exposure therapy for posttraumatic stress disorder in Iraq and Afghanistan War veterans. The American Journal of Psychiatry, 171(6), 640–648. doi: https://doi.org/10.1176/appi.ajp.2014.13121625.
- Rubin, M. (2016). The Perceived Awareness of the Research Hypothesis Scale: assessing the influence of demand characteristics. In.Google Scholar
- Schlickum, M. K., Hedman, L., Enochsson, L., Kjellin, A., & Fellander-Tsai, L. (2009). Systematic video game training in surgical novices improves performance in virtual reality endoscopic surgical simulators: a prospective randomized study. World Journal of Surgery, 33(11), 2360–2367.CrossRefGoogle Scholar
- Schmiedek, F., Lövdén, M., & Lindenberger, U. (2010). Hundred days of cognitive training enhance broad abilities in adulthood: findings from the COGITO study. Frontiers in Aging Neuroscience, 2.Google Scholar
- Sidman, M. (1966). Tactics of scientific research: evaluating experimental data in psychology. Oxford: Basic Books.Google Scholar
- Smith, G. E., Housen, P., Yaffe, K., Ruff, R., Kennison, R. F., Mahncke, H. W., & Zelinski, E. M. (2009). A cognitive training program based on principles of brain plasticity: results from Improvement in Memory with Plasticity-based Adaptive cognitive Training (IMPACT) study. Journal of the American Geriatrics Society, 57(4), 594–603.CrossRefGoogle Scholar
- Stierlin, A. S., Herder, K., Helmbrecht, M. J., Prinz, S., Walendzik, J., Holzmann, M., … Kilian, R. (2014). Effectiveness and efficiency of integrated mental health care programmes in Germany: study protocol of an observational controlled trial. BMC Psychiatry, 14, 163. doi: https://doi.org/10.1186/1471-244X-14-163.
- Strobach, T., & Karbach, J. (Eds.). (2016). Cognitive training: an overview of features and applications. New York: Springer.Google Scholar
- Subramaniam, K., Luks, T. L., Garrett, C., Chung, C., Fisher, M., Nagarajan, S., & Vinogradov, S. (2014). Intensive cognitive training in schizophrenia enhances working memory and associated prefrontal cortical efficiency in a manner that drives long-term functional gains. NeuroImage, 99, 281–292. https://doi.org/10.1016/j.neuroimage.2014.05.057.CrossRefPubMedPubMedCentralGoogle Scholar
- Tang, Y. Y., Ma, Y., Wang, J., Fan, Y., Feng, S., Lu, Q., et al. (2007). Short-term meditation training improves attention and self-regulation. Proceedings of the National Academy of Sciences of the United States of America, 104(43), 17152–17156. https://doi.org/10.1073/pnas.0707678104.CrossRefPubMedPubMedCentralGoogle Scholar
- Tsai, N., Buschkuehl, M., Kamarsu, S., Shah, P., Jonides, J., & Jaeggi, S. M. (2018). (Un)Great expectations: the role of placebo effects in cognitive training. Journal of Applied Research in Memory and Cognition, 7(4), 564–573. https://doi.org/10.1016/j.jarmac.2018.06.001.
- Valdes, E.G., Andel, R., Lister, J.J., Gamaldo, A., & Edwards, J.D. (2017). Can cognitive speed of processing training improve everyday functioning among older adults with psychometrically defined mild cognitive impairment? Journal of Aging and Health, 898264317738828. https://doi.org/10.1177/0898264317738828.
- Van Dam, N. T., van Vugt, M. K., Vago, D. R., Schmalzl, L., Saron, C. D., Olendzki, A., et al. (2018). Mind the hype: a critical evaluation and prescriptive agenda for research on mindfulness and meditation. Perspectives on Psychological Science, 13(1), 36–61. https://doi.org/10.1177/1745691617709589.CrossRefPubMedGoogle Scholar
- Voss, M.W., Prakash, R.S., Erickson, K.I., Basak, C., Chaddock, L., Kim, J. S., … Kramer, A. F. (2010). Plasticity of brain networks in a randomized intervention trial of exercise training in older adults. Frontiers in Aging Neuroscience, 2. https://doi.org/10.3389/fnagi.2010.00032.
- Walton, A.G. (2016). Do brain training games work, or is it the placebo effect? Forbes.com. Retrieved from https://www.forbes.com/sites/alicegwalton/2016/06/21/does-brain-training-work-or-is-it-all-placebo/#3b654dc67497. Accessed 1 Nov 2018.
- Weintraub, S., Dikmen, S.S., Heaton, R.K., Tulsky, D.S., Zelazo, P.D., Bauer, P.J., … Gershon, R.C. (2013). Cognition assessment using the NIH toolbox. Neurology, 80(11 Suppl 3), S54–64. https://doi.org/10.1212/WNL.0b013e3182872ded.
- Wexler, B.E., Iseli, M., Leon, S., Zaggle, W., Rush, C., Goodman, A., … Bo, E. (2016). Cognitive priming and cognitive training: immediate and far transfer to academic skills in children. Scientific Reports, 6, 32859. doi: https://doi.org/10.1038/srep32859.
- Willis, S.L., Tennstedt, S.L., Marsiske, M., Ball, K., Elias, J., Koepke, K.M., … Group, A.S. (2006). Long-term effects of cognitive training on everyday functional outcomes in older adults. JAMA, 296(23), 2805–2814.Google Scholar
- Zhao, W., Hill, M.D., & Palesch, Y. (2012). Minimal sufficient balance—a new strategy to balance baseline covariates and preserve randomness of treatment allocation. Statistical Methods in Medical Research https://doi.org/10.1177/0962280212436447.
- Zwaan, R.A., Etz, A., Lucas, R.E., & Donnellan, M. B. (2017). Making replication mainstream. The Behavioral and Brain Sciences, 1–50. https://doi.org/10.1017/S0140525X17001972.