JMIR Publications

ABSTRACT

Background:

Gamified digital training may support long-term engagement in aging populations, yet randomized evidence linking behavioral effects to convergent neuroimaging outcomes remains limited.

Objective:

To test whether a home-based digital Mahjong (DMG) program enhances cognition in community-dwelling older adults and to characterize training-related brain changes using multimodal MRI.

Methods:

We conducted a single-blind, parallel-group randomized controlled trial in Taipei, Taiwan (July 2020–November 2021). Community-dwelling adults aged ≥55 years were randomized (1:1) to a 6-month DMG intervention or to no intervention. The intervention consisted of two 30-minute sessions per week delivered via an iPad app, in which participants played against three computer-controlled opponents, and included an incentivized walking component (Mi Band step tracking with in-game tokens). Primary MRI outcomes were gray matter volume (GMV), regional homogeneity (ReHo), fractional amplitude of low-frequency fluctuations (fALFF), and global brain connectivity (GBC). Secondary outcomes included cognition (Montreal Cognitive Assessment), physical activity (IPAQ), mental health (Brief Resilience Scale; Demoralization Scale–Mandarin Version), quality of life (EQ-5D with VAS), physical fitness/body composition, and blood biomarkers. Per-protocol analyses were performed. Voxel-wise imaging analyses used ANCOVA in SPM12 with FWE correction at the cluster level (p<.05).

Results:

Sixty participants were enrolled (30 per group); 29 in the intervention and 27 in the control group completed primary endpoint assessments. Compared with controls, the DMG group showed a greater improvement in MoCA delayed recall (between-group difference -0.79 points; 95% CI -1.538 to -0.042; p=.04). Neuroimaging revealed increased ReHo in the right insula (FWE-corrected p<.05) and decreased GMV in the left frontal pole/orbitofrontal cortex, with reduced fALFF in the left frontal pole. Changes in delayed recall were positively associated with right insular ReHo and also showed significant associations with right anterior cingulate gyrus (ReHo) and with left inferior frontal gyrus and right paracingulate gyrus (fALFF) (all FWE-corrected p<.05). In exploratory dose analyses, right insular ReHo correlated with total practice sessions (r=0.48, p=.009). Among physiological outcomes, the intervention group had a larger reduction in diastolic blood pressure (e.g., -3.50 mmHg; 95% CI -6.91 to -0.09; p=.04), while thyroid-stimulating hormone decreased but remained within the normal range.

Conclusions:

A 6-month home-based digital Mahjong program with scheduled twice-weekly practice improved delayed recall in older adults and induced targeted functional brain changes—most prominently increased right-insular homogeneity—whereas structural frontal alterations did not mirror cognitive gains. Gamified training is a feasible approach to engage salience- and control-related networks and support memory; larger multi-arm studies with preregistered dose–response tests are warranted. Clinical Trial: ClinicalTrials.gov NCT05808426