Individual differences in the neurobiology of fluid intelligence predict responsiveness to training: Evidence from a comprehensive cognitive, mindfulness meditation, and aerobic exercise intervention.

BACKGROUND: Fluid intelligence (Gf) is a critical cognitive ability that is predictive of real-world outcomes, and it has been a persistent aim to characterize its neural architecture. PROCEDURE: We advance our prior research by applying latent class analysis to evaluate individual differences in the neural and cognitive foundations of Gf over the course of a 16-week randomized, multi-modal intervention trial in neurologically healthy, younger adults (N = 424). RESULTS: Controlling for pre-intervention ability, three latent classes described individual performance at post-intervention and one group (n = 71) showed greater gains in visuospatial reasoning and high performance at post-intervention. The high performance group was predicted by larger anterior cingulate cortex, caudate and hippocampus volumes, and smaller middle frontal, insula and parahippocampal cortex volumes. CONCLUSION: Regions that support cognitive control, working memory, and relational processes differentiated individuals who had higher Gf ability at pre-intervention and demonstrated a cumulative better response to the intervention.