Neurobehavioral Mechanisms Influencing the Association Between Generativity, the Desire to Promote Well-Being of Younger Generations, and Purpose in Life in Older Adults at Risk for Alzheimer's Disease

Abstract

Objectives: Generativity, the desire and action to improve the well-being of younger generations, is associated with purpose in life among older adults. However, the neurobehavioral factors supporting the relationship between generativity and purpose in life remain unknown. This study aims to identify the functional neuroanatomy of generativity and mechanisms linking generativity with purpose in life in at-risk older adults.

Methods: Fifty-eight older adults (mean age = 70.8, SD = 5.03, 45 females) with a family history of Alzheimer's disease (AD) were recruited from the PREVENT-AD cohort. Participants underwent brain imaging and completed questionnaires assessing generativity, social support, and purpose in life. Mediation models examined whether social support mediated the association between generativity and purpose in life. Seed-to-voxel analyses investigated the association between generativity and resting-state functional connectivity (rsFC) to the ventromedial prefrontal cortex (vmPFC) and ventral striatum (VS), and whether this rsFC moderated the relationship between generativity and purpose in life.

Results: Affectionate social support mediated the association between generative desire and purpose in life. Generative desire was associated with rsFC between VS and precuneus, and, vmPFC and right dorsolateral prefrontal cortex (rdlPFC). The vmPFC-rdlPFC rsFC moderated the association between generative desire and purpose in life.

Discussion: These findings provide insight into how the brain supports complex social behavior and, separately, purpose in life in at-risk aging. Affectionate social support may be a putative target process to enhance purpose in life in older adults. This knowledge contributes to future developments of personalized interventions that promote healthy aging.

Keywords: Prosociality; Resting-state fMRI; Self-transcendence; Ventral striatum; Ventromedial prefrontal cortex.

Figure 1.

Diagram of the mediation model results between generative desire and purpose in life. The a path represents the effect of generative desire on affectionate social support; the b path represents the effect of affectionate social support on purpose in life; the c path represents the total effect of generative desire on purpose in life; the cʹ path represents the direct effect of generative desire after controlling for affectionate social support; and the ab path represents the indirect effect. *p < .05. **p < .01.

Figure 2.

Ventromedial prefrontal cortex (vmPFC) to right dorsolateral prefrontal cortex (rdlPFC) resting-state functional connectivity (rsFC) moderating the effect of generative desire on purpose in life. Panel A shows a diagram of the model and Panel B shows the interaction effect. Generative desire and resting-state connectivity values are centered to their means. Purpose in life was regressed on generative desire at low (−1 standard deviations), moderate (mean), and high (+1 standard deviations) levels of resting-state functional connectivity.

Figure 3.

Ventromedial prefrontal cortex (vmPFC) to right dorsolateral prefrontal cortex (rdlPFC) and ventral striatum (VS) to right precuneus resting-state functional connectivity (rsFC) is associated with generative desire. Panel A displays the ventromedial prefrontal cortex seed (blue) to right dorsolateral prefrontal cortex connectivity (yellow). Panel B displays the VS seed (blue) to right precuneus connectivity. Clusters are overlaid on a standard template and are corrected for multiple comparisons.