Forget your keys, remember your words!
The link between intelligence and longevity has been a subject of ongoing scientific inquiry. While general intelligence is known to predict survival, the specific contributions of different cognitive abilities in old age remain poorly understood. The Developmental and Educational Psychology Group (Denis Gerstorf) addressed this gap by analyzing longitudinal data from the Berlin Aging Study, focusing on a range of cognitive tasks including perceptual speed, episodic memory, verbal fluency, and verbal knowledge. Using a sophisticated joint multivariate longitudinal survival model, they investigated the unique predictive power of each cognitive ability on mortality risk, while controlling for various demographic and health-related factors. They revealed that, among the diverse cognitive measures, only verbal fluency demonstrated a significant and unique association with survival, suggesting a more salient role for this specific ability in predicting mortality in older adults. Find out more in their Psychological Science Article!
Abstract
Intelligence is known to predict survival, but it remains unclear whether cognitive abilities differ in their relationship to survival in old age. We analyzed longitudinal data of 516 healthy adults (age: M = 84.92 years, SD = 8.66 years at Wave 1) from the Berlin Aging Study (Germany) on nine tasks of perceptual speed, episodic memory, verbal fluency, and verbal knowledge, and a general composite intelligence score. There were eight waves, with up to 18 years of follow- up; all participants were deceased by the time of analysis. We used a joint multivariate longitudinal survival model to estimate the unique contribution of each cognitive ability in terms of true (i.e., error-free) current value and current rate of change when predicting survival. Additional survival covariates included age at first occasion, sex, sociobiographical status, and suspected dementia. Only the two verbal-fluency measures were uniquely predictive of mortality risk. Thus, verbal fluency showed more salient associations with mortality risk than did measures of perceptual speed, episodic memory, and verbal knowledge.