The temporal dynamics of decision under risk

Abstract

Event Abstract Back to Event The temporal dynamics of decision under risk Laurence Hunt1*, Matthew Rushworth2 and Tim Behrens1 1 University of Oxford, FMRIB Centre, United Kingdom 2 University of Oxford, Department of Experimental Psychology, United Kingdom The functional neuroanatomy of value-based decision has been widely investigated using functional MRI and lesion methods. Neither of these techniques provides sufficient temporal resolution to investigate brain activity as a decision unfolds. We therefore measured simultaneous M/EEG in 19 subjects as they performed a simple economic decision-making task. Subjects weighed the probability of receiving monetary reward on two options with the magnitude of reward that could be attained. Subject choices matched predictions from descriptive economic models of behaviour, and reaction times correlated negatively with the difference in value (=reward magnitude x probability) between the two options. When making the decision, a component correlating with this value difference was identified over frontal EEG electrodes, peaking 350ms before the subject responded. A similar component was also found in MEG magnetometers at the same timepoint. At the time of feedback, a feedback-related negativity (FRN) component was identified in EEG sensors over frontal midline electrodes, approximately 250ms after feedback was received. Again, a similar component was found in MEG magnetometers. We employed the multiple sparse priors (MSP) source reconstruction algorithm implemented in SPM8 to investigate the neuroanatomical basis of these signals. FRN signals were localised to anterior cingulate cortex, and buttonpresses localised to primary motor cortex, validating the accuracy of forward modelling and MSP source reconstruction. Source reconstruction of the value difference signal at the time of the decision localised to a ventromedial portion of prefrontal cortex (VMPFC), frequently identified as signalling this metric in FMRI studies of value-based decision. Immediately prior to this, source reconstruction of a signal corresponding to the sum of both option values also localised to VMPFC. This result suggests that the metric signalled by VMPFC may evolve through time as a decision is made. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Neurocognition and Functional Connectivity Citation: Hunt L, Rushworth M and Behrens T (2010). The temporal dynamics of decision under risk. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00350 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 07 Apr 2010; Published Online: 07 Apr 2010. * Correspondence: Laurence Hunt, University of Oxford, FMRIB Centre, Oxford, United Kingdom, lhunt@fmrib.ox.ac.uk Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Laurence Hunt Matthew Rushworth Tim Behrens Google Laurence Hunt Matthew Rushworth Tim Behrens Google Scholar Laurence Hunt Matthew Rushworth Tim Behrens PubMed Laurence Hunt Matthew Rushworth Tim Behrens Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.