Processing speed and working memory are predicted by components of successful aging: a HUNT study

Area of Science:

• Gerontology
• Cognitive Neuroscience
• Public Health

Background:

• Cognitive heterogeneity is a known phenomenon in aging, varying both within and between individuals.
• Understanding the factors contributing to cognitive heterogeneity is crucial for promoting healthy aging.

Purpose of the Study:

• To investigate the relationship between cognitive heterogeneity in aging and subgroups of successful aging.
• To determine if different definitions of successful aging correlate with specific cognitive functions.

Main Methods:

• A representative sample of 65 older adults (aged 70-89) from the Nord-Trøndelag Health Survey (HUNT3) participated.
• Cognitive functions were assessed using the Wechsler Memory Scale (WMS-III) and Wechsler Adult Intelligence Scale (WAIS-III).
• Successful aging was defined by absence of disease, high functioning, active engagement, or a combination thereof; linear regression analyzed cognitive domains against aging groups, controlling for age, sex, and education.

Main Results:

• Processing speed was associated with absence of disease, younger age, and being female.
• Working memory correlated with absence of disease and higher education.
• Other cognitive domains (verbal, visuospatial, episodic memory) showed no significant relationship with any successful aging definition.

Conclusions:

• Successful aging, defined by absence of disease, is domain-specifically linked to processing speed and working memory.
• Other components of successful aging did not show domain-specific cognitive associations.
• These findings highlight the importance of disease absence in maintaining specific cognitive functions during aging.