Medial prefrontal activation as a neural predictor of cognitive training gains in older adults with amnestic mild cognitive impairment: exploratory evidence

Background Not all individuals benefit equally from cognitive training, making it essential to identify neural markers that can predict individual responsiveness, particularly among those at the early stages of cognitive impairment. Methods This study investigated whether prefrontal activation measured by functional near-infrared spectroscopy (fNIRS) during three categories of training tasks (attentional, imagery, and associative) predicts cognitive gains in older adults. Twenty-two older adults with amnestic mild cognitive impairment (aMCI) completed a 12-week digital-device–based cognitive training program comprising 12 tasks (6 attentional, 3 imagery, 3 associative). Prefrontal activation was recorded via fNIRS during each task. Cognitive improvement was assessed using the Alzheimer's Disease Assessment Scale–Cognitive Subscale at baseline and 3 months ( n = 22). Results Among the three task categories, only attentional training was associated with prefrontal activation patterns that significantly predicted cognitive improvement at 3 months. Specifically, greater activation in the left mPFC during attentional training was negatively associated with ADAS-Cog scores (β = –.443, p = 0.039), indicating that individuals with higher activation exhibited greater cognitive improvement. Conclusion The findings suggest that increased medial prefrontal activation during attentional training reflects compensatory engagement and task-related control processes, which in turn predict larger cognitive gains in individuals with aMCI. These results indicate that neural activation measured during training can serve as a reliable predictor of subsequent cognitive gains, offering a potential foundation for designing personalized and adaptive educational programs.