Adaptive visuospatial n-back training improves audiovisual integration and executive control in older adults

Age-related declines in visuospatial working memory (WM), associated with the visuospatial sketchpad in Baddeley's WM model, may impair cognitive functions including spatial orientation and visuospatial integration. Understanding these declines is important for designing interventions to support older adults' functional independence. Although WM training has shown potential to improve WM performance and produce near transfer effects, its far transfer effects, particularly on audiovisual integration and attention, remain unclear. In this study, the training group (TG) completed five sessions of adaptive visuospatial n-back training, while the control group (CG) served as a non-contact CG. Cognitive assessments of WM, audiovisual integration, and attention were conducted before and after training for both groups. Across training sessions, task difficulty increased in the TG, suggesting learning and adaptation within the trained task. The trained 1-back task further elicited greater P200 amplitudes in the fronto-central, central, and centro-parietal regions during match trial processing in the TG, but not in the CG, indicating that adaptive visuospatial n-back training may induce task-specific learning and neural modulation. The TG also performed better than the CG on the untrained Corsi block test at posttest, suggesting a potential near transfer effect on visuospatial WM. Additionally, in the audiovisual discrimination task, the TG showed reduced audiovisual integration behaviorally after training, whereas P300-related audiovisual integration increased. In the attention network test, the TG showed greater parietal P300 amplitudes during conflict stimulus processing at posttest, despite the absence of reliable behavioral improvement. These findings suggest potential far transfer of WM training to audiovisual integration and attention, although the behavioral and electrophysiological evidence was not fully consistent across outcomes. Overall, these results suggest the plasticity of the aging brain and the feasibility of non-pharmacological cognitive interventions in mitigating age-related cognitive decline.