Amygdala Persistence in Aging: Replication and Extension of Puccetti et al. (2021)

Age-related differences in affect are well established, but their neural mechanisms remain unclear. In a preregistered replication of Puccetti et al. (2021) and extension, we examined age, affect, left-amygdala negative persistence, and amygdala-ventromedial prefrontal cortex (vmPFC) task-based connectivity using MIDUS 3 daily diary and fMRI data. Older age predicted higher positive and lower negative affect in the daily diary sample (N = 1,168; ps < .001). In the primary diary + fMRI sample (N = 81; ages 48-95, 61.7% female, 82.7% White), greater persistence predicted higher raw negative affect ({beta} = 0.278, 95% CI [0.012, 0.544], p = .020); associations with positive and log-transformed negative affect were nonsignificant (ps [≥] .063). Older age predicted lower persistence in the final fMRI sample (N = 127; {beta} = -0.00260, 95% CI [-0.00504, -0.00016], p = .018), but this association was weaker in the primary diary + fMRI sample (p = .200), with no evidence of mediation. Greater anterior vmPFC connectivity predicted lower raw negative affect ({beta} = -0.106, 95% CI [-0.223, 0.012], p = .039) and log-transformed negative affect (p = .014). In MIDUS Refresher 1, affect estimates were directionally similar but nonsignificant (N = 48; ps [≥] .081), whereas the age-persistence estimate reversed direction. These findings provide partial support for amygdala persistence and task-based connectivity as neural correlates of daily affect, while highlighting variability in the magnitude and replicability of fMRI-behavior associations.