During intertemporal choice (IT) future outcomes are usually devaluated as a function of the delay, a phenomenon known as temporal discounting (TD). Based on task-evoked activity, previous neuroimaging studies have described several networks associated with TD. However, given its relevance for several disorders, a critical challenge is to define a specific neural marker able to predict TD independently of task execution. To this aim, we used resting-state functional connectivity MRI (fcMRI) and measured TD during economic choices several months apart in 25 human subjects. We further explored the relationship between TD, impulsivity and decision uncertainty by collecting standard questionnaires on individual trait/state differences. Our findings indicate that fcMRI within and between critical nodes of task-evoked neural networks associated with TD correlates with discounting behavior measured a long time afterwards, independently of impulsivity. Importantly, the nodes form an intrinsic circuit that might support all the mechanisms underlying TD, from the representation of subjective value to choice selection through modulatory effects of cognitive control and episodic prospection.
Interindividual Variability in Functional Connectivity as Long-Term Correlate of Temporal Discounting
Public Library of Science, San Francisco, CA , Stati Uniti d'America
PloS one 10 (2015). doi:10.1371/journal.pone.0119710
info:cnr-pdr/source/autori:Calluso, Cinzia; Tosoni, Annalisa; Pezzulo, Giovanni; Spadone, Sara; Committeri, Giorgia/titolo:Interindividual Variability in Functional Connectivity as Long-Term Correlate of Temporal Discounting/doi:10.1371/journal.pone.01197