Flexible coding of task rules in frontoparietal cortex

Abstract

Event Abstract Back to Event Flexible coding of task rules in frontoparietal cortex Alexandra Woolgar1*, Soheil Afshar1, Mark A. Williams1 and Anina N. Rich1 1 Macquarie University, Department of Cognitive Science and ARC Centre of Excellence in Cognition and its Disorders, Australia Background Humans are characterised by diverse and flexible behaviour. How does the brain achieve the flexible cognitive control that is required? Several theories implicate frontoparietal cortex, which is thought to represent the information needed for current behaviour and to bias processing towards task-relevant information elsewhere in the brain. In particular, frontoparietal cortex is thought to structure and maintain task sets or rules. For behaviour to be flexible, however, the system must rapidly reorganise as mental focus changes. We have previously demonstrated this reorganisation, or “adaptive coding”, in the visual domain, with frontoparietal cortex adjusting to code perceptual information more strongly when visual input is weak. Here, we test whether this rapid reorganisation is also seen in the conceptual domain, for task rules. Methods 20 participants learnt 4 rules determining which of 4 buttons should be pressed in response to a blue square shown in one of 4 possible horizontal locations on a screen. Two of the rules were conceptually simple (“easy”) while the other two rules were more complex (“hard”). On each trial, the current rule was cued by the background colour of the screen. Functional magnetic resonance imaging (fMRI) data were acquired on a 3T Siemens Verio scanner while participants performed alternating blocks of easy and hard rules. We used Multivoxel Pattern Analysis (MVPA) to characterise the extent to which activity patterns in frontoparietal cortex discriminated between (“coded”) the task rules, stimulus positions, and button press responses, in easy and hard blocks separately. Results Participants were significantly slower and less accurate for the hard compared to easy rules. In a restricted set of frontal and parietal “multiple-demand” (MD) brain regions, chosen a priori for their common response to a range of cognitive demands, coding dynamically adjusted between easy and hard blocks. MD coding of rule increased in hard compared to easy blocks, suggesting increased focus on this task element as it became more cognitively demanding. At the same time, MD coding of responses decreased in hard blocks, suggesting a redistribution of response information as focus on task rules increased. Discussion The results suggest an adaptive frontoparietal system that rapidly reorganises in response to changing conceptual demands. This system may provide the neural basis for flexible control of human behaviour. Acknowledgements This work was supported under the Australian Research Council (ARC)’s Discovery Projects funding scheme (DP12102835). AW, MAW and AR are recipients of ARC Fellowships (Discovery Early Career Researcher Award, DECRA, DE120100898, Queen Elizabeth II Research Fellowship DP0984919, and Australian Postdoctoral Fellowship DP0984494, respectively). Keywords: cognitive control, fMRI, MVPA, rules, frontoparietal, pattern analysis, Attention Conference: ACNS-2013 Australasian Cognitive Neuroscience Society Conference, Clayton, Melbourne, Australia, 28 Nov - 1 Dec, 2013. Presentation Type: Oral Topic: Executive Processes Citation: Woolgar A, Afshar S, Williams MA and Rich AN (2013). Flexible coding of task rules in frontoparietal cortex. Conference Abstract: ACNS-2013 Australasian Cognitive Neuroscience Society Conference. doi: 10.3389/conf.fnhum.2013.212.00161 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: 15 Oct 2013; Published Online: 25 Nov 2013. * Correspondence: Dr. Alexandra Woolgar, Macquarie University, Department of Cognitive Science and ARC Centre of Excellence in Cognition and its Disorders, Sydney, NSW, 2109, Australia, alexandra.woolgar@mrc-cbu.cam.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 Alexandra Woolgar Soheil Afshar Mark A Williams Anina N Rich Google Alexandra Woolgar Soheil Afshar Mark A Williams Anina N Rich Google Scholar Alexandra Woolgar Soheil Afshar Mark A Williams Anina N Rich PubMed Alexandra Woolgar Soheil Afshar Mark A Williams Anina N Rich 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.