Cortical grey matter mediates increases in model-based control and learning from positive feedback from adolescence to adulthood

Abstract

Adolescents undergo maturation in cognition and brain structure. Model-based (MB) control is known to increase from childhood to young adulthood, which is mediated by cognitive abilities. Here, we asked two questions unaddressed in previous developmental studies: Firstly, what are the brain structural correlates of age-related increases in MB control? Secondly, how are age-related increases in MB control from adolescence to adulthood influenced by motivational context? A developmental sample (n=103, age: 12-42) completed structural MRI and an established task to capture MB control. The task was modified with respect to outcome valence by including (1) reward and punishment blocks to manipulate the motivational context and (2) an additional choice test to assess learning from positive vs. negative feedback. After replicating that an age-dependent increase in MB control is mediated by cognitive abilities, we demonstrate first-time evidence that grey matter density (GMD) in the parietal cortex mediates the increase of MB control with age. While motivational context did not relate to age-related changes in MB control, learning from positive feedback improved with age. Meanwhile, negative feedback learning showed no age effects. We present a first report that an age-related increase in learning from positive feedback was mediated by reduced GMD in the parietal, medial and dorsolateral prefrontal cortex. Our findings indicate that efficient brain maturation, as putatively reflected in lower GMD, in distinct and partially overlapping brain regions is a key developmental step towards age-related increases in planning and value-based choice.

Impaired flexible reward learning is associated with blunted reinforcement sensitivity and attenuated learning and choice signals in ventral striatum and parietal cortex of ADHD patients

“…The copyright holder for this preprint this version posted April 17, 2023. ; https://doi.org/10.1101/2023.04.14.23288555 doi: medRxiv preprint reversal learning . Reinforcement learning has been shown to undergo substantial neurodevelopmental changes (Nussenbaum and Hartley 2019, Weiss, Kruppa et al 2021, Scholz, Waltmann et al 2023, and has been used to study a wide range of psychiatric disorders (Chantiluke, Barrett et al 2015, Geisler, Ritschel et al 2017). Yet, there is only one study available that directly examined RL in adolescent ADHD patients during fMRI (Hauser, Iannaccone et al 2014).…”