Italian Validation of the dNA Scale and Its Correlation With Neurocognitive Variables

Italian Validation and Factor Structure of the dynamic Neurocognitive Adaptation Scale (dNA)

The primary outcome of this study is the successful Italian validation of the dNA scale. Specifically, investigators expect to replicate the results of the English-language version (Cieri et al., accepted), with a four-factor structure, no multicollinearity (r \< 0.95) or insufficient common variance (r \< 0.3), satisfactory Kaiser-Meyer-Olkin (KMO) indices (\>0.70), significant Bartlett's sphericity test (\<0.01), and high internal consistency as indicated by Cronbach's alpha (\>0.80).

Association Between Activity Engagement, Temporal Maintenance, and Educational Attainment

Investigators expect that greater engagement in the activities under investigation, as well as their dynamic maintenance over time, reflected in higher dNA scale scores, will be positively associated with higher educational attainment.

Association Between dNA scale and Neuropsychological Measures

Investigators expect that higher dNA scale scores will be positively associated with better neuropsychological performance, particularly in episodic memory and executive function domains. Specifically, cognitive performance will be assessed using a standardized battery, including the MMSE (or MoCA) for global cognition, Rey Auditory Verbal Learning Test (RAVLT) for verbal long-term memory, Trial Making Test (TMT) Form B for executive functioning, Digits Forward and Backward subtests (WAIS or WAIS-III) for working memory, Wechsler Memory Scale Logical Memory II (or Prose Memory), and Stroop Test for cognitive inhibition and information processing speed. These measures will provide both an overall cognitive assessment and domain-specific outcomes, which will be further explored for their expected association with the dNA scale scores.

Association Between dNA scale and Structural and Functional Brain Organization

This outcome measure evaluates the relationship between dNA scale scores and functional brain network activity and organization derived from functional magnetic resonance imaging (fMRI). Within diagnostic groups (SMC, MCI, AD), higher scores on the dNA scale are hypothesized to be associated with increased activation and greater functional segregation within the task-negative network (default network, DN), alongside greater deactivation in task-positive networks, including the dorsal attention network (DAN) and the frontoparietal control network (FPCN). Functional connectivity analyses will be used to quantify both within-network segregation and between-network integration. These neuroimaging-derived metrics will be statistically associated with dNA scale scores using appropriate regression models within each diagnostic group.

Association Between dNA scale and Biomarkers of Pathological Aging

This additional outcome measure will evaluate the relationship between dNA scale scores and previously collected biomarkers, contingent upon data availability. Indeed, participating centers that have the capability may also retrieve information from the participant's medical record regarding biomarkers of pathological aging (e.g., APoE). Potential association between dNA scale scores and previously collected biomarkers will be further explored, within the healthy elderly sample and each diagnostic group (SMC, MCI, AD).