Efficacy of smartphone application–based multi-domain cognitive training in non-demented older adults

Background. As the elderly population and the prevalence of dementia increase, the importance of cognitive training for dementia prevention is being emphasized. To increase accessibility to cognitive training programs among elderly individuals, the InBrain Trainer (IBT), a smartphone application–based cognitive training including 12 cognitive tasks covering language, calculation, memory, attention, visuospatial function, and frontal/executive function was developed. The purpose of this study was to examine the effectiveness of the IBT by investigating cognitive improvement and prefrontal cortex activation in non-demented older adults using functional near-infrared spectroscopy (fNIRS). Methods. The IBT, an android-based cognitive training software program, was downloaded to the participant’s smartphone or tablet computer and administered at home. Non-demented older adults (51 intervention participants, 50 control participants) were enrolled in this study. The IBT consisted of 12 tasks derived from two tasks each for six cognitive domains. Each task has 4 difficulty levels, and 48 blocks (12 tasks × 4 levels) were used to frame the amount of cognitive tasks for ≥1.5 hours per day, 5 days per week, for 16 weeks. The intervention group received gradually increasing difficulty tasks as homework through a mobile phone application for 16 weeks. To verify the effectiveness of the IBT as the outcome measure, the InBrain Cognitive Screening Test (CST), fNIRS, and various scales were compared between the intervention and control groups at two time points (baseline and after 16 weeks of cognitive training). Results. Among 101 participants, 85 non-demented older adults (84.1%) completed the study protocol and were included in the final analysis, including 41 (80.3%) in the cognitive intervention group and 44 (88.0%) in the control group. The group-by-time interaction effect was significant only in the language domain score of the InBrain CST. When the language domain subtest scores were analyzed, significant interaction effects were presented in the phonemic generative naming test but not in the semantic generative naming test or the Difficult Naming Test. In the hemodynamic response of the prefrontal cortex measured by all channels of fNIRS, the group-by-time interaction effect was significant only in the dorsolateral prefrontal cortex during the Stroop incongruent task. There were no group-by-time interaction effects in the second outcome measures of various scales. Conclusion. Our study is meaningful in that cognitive training software implemented as an application on personal devices such as smartphones and tablet computers led not only to cognitive enhancement, but also increased prefrontal lobe activation. Therefore, cognitive training applications including the IBT are expected to provide effective cognitive intervention without time or space constraints both in a clinical setting and at home.