Journal of Child and Adolescent Behavior
Open Access

Research Article

Discounting and VBM

Department of Neurology, Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, London, UK

*Corresponding Author:

Bernal-Casas David
Department of Neurology
Wellcome Trust Centre for Neuroimaging
Institute of Neurology, University College London
12 Queen Square - London - WC1N 3BG, UK
Tel: ++44 (0) 20 3448 4362
Fax: ++44 (0) 20 7813 1420
E-mail: bernalgps@gmail.com

Received Date: August 27, 2015 Accepted Date: October 05, 2015 Published Date: October 13, 2015

Citation: Bernal-Casas D, Ziegler G, Moutoussis M, Prabhu G, Dolan R (2015) Discounting and VBM. J Child Adolesc Behav 3:251. doi:10.4172/2375-4494.1000251

Copyright: © 2015 Bernal-Casas D, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Adolescence is a period of significant development in cognition, behavior, and the brain. Neural development during human adolescence involves highly coordinated and sequenced events, characterized by both progressive and regressive processes. In this study we were interested in the emergence of self-control as indexed by impulsivity, and the malleability to change their own preferences, a trait linked to pro-social behavior. We used a computationally derived measure of impulsivity based on an inter-temporal choice task, to examine how its trajectory over adolescence related to maturational morphological brain changes estimated by voxel based morphometry (VBM). We observed a global decrease in grey matter volume over the course of adolescence. Over and above these changes greater impulsivity as indexed in a higher self-discounting parameter was linked to greater grey matter volume within right dorsomedial prefrontal cortex (DMPFC). Likewise we observed that greater choice stochasticity, indexed by a higher decision-variability parameter (reflecting more “noisy” and “exploratory” choices) was linked to greater grey matter volume within bilateral dorsal striatum. We interpret these findings as suggestive that delay in cortical maturation within impulsivity-related brain areas, possibly linked to sluggish neuronal pruning, is a key mediator of impulsivity. Finally, the ability to shift towards other’s behavior was positively correlated to grey matter volume within right dorsolateral prefrontal cortex (DLPFC). This result seems to contradict previous findings but does not; DLPFC undergoes a normal pruning across adolescence, however the more grey matter participants had at the onset of the puberty, the more malleable were in shifting towards other’s behaviour. This finding supports the idea that pro-social traits are developed in childhood.

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