Impact of Chatbot-Based Cognitive Training on Cognitive Function and White Matter Integrity in Cognitively Unimpaired Older Adults: Randomized Controlled Trial

BACKGROUND: Cognitive training may enhance cognition and support brain health during aging, but few trials have evaluated readily accessible chatbot-based programs with neuroimaging outcomes. OBJECTIVE: This study aimed to evaluate the effects of a chatbot-based cognitive training program on white matter microstructural organization and cognition in cognitively unimpaired older adults. METHODS: In a single-blind randomized controlled trial, 72 cognitively unimpaired older adults were assigned to chatbot-based cognitive training (30 min/day, 5 days/week for 12 weeks; n=37) or a no-intervention control (n=35). Diffusion tensor imaging at baseline and 12 weeks quantified fractional anisotropy (FA) in predefined white matter tracts, and cognition was assessed with the Cambridge Neuropsychological Test Automated Battery. RESULTS: Groups were comparable at baseline. After 12 weeks, the training group showed significantly less FA reduction than controls in the bilateral tapetum and right posterior thalamic radiation, surviving false discovery rate control (P<.05). The training group also improved on Paired Associates Learning (PAL), an episodic memory measure (P=.04). PAL improvement was positively associated with FA change in the right posterior thalamic radiation and right sagittal stratum (false discovery rate-adjusted P=.04 for each). CONCLUSIONS: These findings suggest that a 12-week chatbot-based cognitive training program may support episodic memory and the relative maintenance of white matter microstructural organization in selected pathways in cognitively unimpaired older adults, consistent with a brain-maintenance framework. TRIAL REGISTRATION: CRIS KCT0004630; https://tinyurl.com/4xfesb68.