Virtual reality video game improves high-fidelity memory in older adults
Authors: Adam Gazzaley
Roger Anguera-Singla
Peter E Wais
Melissa Arioli
Journal: Scientific Reports (2021)
Discipline: Multidisciplinary
Keywords: Therapeutic interventions; long-term memory; virtual reality; spatial wayfinding game; cognitive intervention
Affiliations: Department of Neurology, Neuroscape and Weill Institute for Neurosciences, University of California, San Francisco, UCSF-MC0444, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA. ., Department of Neurology, Neuroscape and Weill Institute for Neurosciences, University of California, San Francisco, UCSF-MC0444, 675 Nelson Rising Lane, San Francisco, CA, 94158, USA., Departments of Physiology and Psychiatry, University of California, San Francisco, San Francisco, USA.

Abstract:  Therapeutic interventions have not yet been shown to demonstrate restorative effects for declining long-term memory (LTM) that affects many healthy older adults. We developed a virtual reality (VR) spatial wayfinding game (Labyrinth-VR) as a cognitive intervention with the hypothesis that it could improve detailed, high-fidelity LTM capability. Spatial navigation tasks have been used as a means to achieve environmental enrichment via exposure to and learning about novel and complex information. Engagement has been shown to enhance learning and has been linked to the vitality of the LTM system in the brain. In the current study, 48 older adults (mean age 68.7 ± 6.4 years) with average cognitive abilities for their age were randomly assigned to 12 h of computer game play over four weeks in either the Labyrinth-VR or placebo control game arms. Promptly before and after each participant's treatment regimen, high-fidelity LTM outcome measures were tested to assess mnemonic discrimination and other memory measures. The results showed a post-treatment gain in high-fidelity LTM capability for the Labyrinth-VR arm, relative to placebo, which reached the levels attained by younger adults in another experiment. This novel finding demonstrates generalization of benefits from the VR wayfinding game to important, and untrained, LTM capabilities. These cognitive results are discussed in the light of relevant research for hippocampal-dependent memory functions. 

Retracted: No

PubPeer comments:
 I hope the authors can clarify a few questions about this paper and its relation to their preregistration. u2022 The paper was registered at clinicaltrials.gov, with an analysis plan dated 8-22-2019 but that was first posted on 2-5-2020. The study apparently started on 10-1-2019. The paper was submitted on 5-21-2020. Was this preregistered or was the registration posted after completion? The paper also cites an NIH grant that appears to have ended in 2019, and it s not clear how this project is related to that grant or to the registration. If the project was funded by a different grant post 2018, the study would have needed to be in clinicaltrials.gov within 21 days of enrollment of the first participant. It s not clear exactly how the reported study is related to the already completed grant or to the cited the clinicaltrials.gov registration. u2022 There are a number of differences between the cited registration and the reported study. The paper did not give explanations for the differences. Those included: --- The registration specified 300 participants, but the paper had 49. This might be the pilot study mentioned in the registration, but the results in the registration don t seem to match up with the pilot study in all respects. --- the registration mentions another outcome measure (TOVA) that was not reported in the paper. It also mentions followup assessments after 90 days that weren t reported. And, it mentioned neuroimaging methods that aren t reported. --- The registration mentioned 3 arms for this study (two intervention conditions and a control condition), but only one of the two intervention conditions is reported. --- The analysis plan in the registration says  Each of the independent cognitive measures will be analyzed with three-factor repeated-measures ANOVA as 2 Times (T 1 | T2) X 3 Conditions (Game manipulation 1 | Game manipulation 2 | Placebo Control. Results showing are greater for either training condition than for the placebo control condition, will show target engagement and the beneficial effect from the training intervention on cognitive performance for participants. Statistical comparisons in each ANOVA will use the threshold 0.05 for reliable differences between factors. Each outcome measure is independent of the others and could be considered a sign of training effects in its own right. As follow- up comparisons, the analyses will also be based on ANCOVA, which may better account for variability in the groupsu2019 baseline performance that can dilute the statistical significance of training-induced gains evident in change scores T2-T1. -- The paper didn t report an ANCOVA. Also, if any of the outcome measures would have been treated as evidence for far transfer, then they merit correction for multiple tests and shouldn t be treated as independent. If the paper had tested 20 outcome measures and would have counted any p .05 result as evidence of far transfer, then we would expect one significant result by change (on average). It is necessary to correct for multiple tests if each would be counted as evidence for the key hypothesis. There were no correction for multiple tests across the different outcome measures, and only one outcome measure showed an interaction effect at p .05. u2022 There were 49 participants in total with 4 dropped from the intervention and 3 from the control, which should give 21 group if they were evenly split. The paper doesn t specify if they were. u2022 The analysis is described as a mixed-design with condition as a between-group factor, but the critical ANOVA lists 20 degrees of freedom in the denominator. With 21 people in two groups, it s not clear how they arrived at that number. The analysis suggests that there was some form of pairing or repeated measures grouping, but it s not clear what that would be. u2022 The last author (Adam Gazzaley) founded and runs a Akili Interactive, a company that produces and markets a computer-based brain training product. Whether or not that should be considered a COI is unclear. The authors declared no conflicts of interest related to this paper. ,