Coding dichotomy in lateral intraparietal cortex (LIP) of the macaque monkey and its role in spatial attention

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Event Abstract Back to Event Coding dichotomy in lateral intraparietal cortex (LIP) of the macaque monkey and its role in spatial attention Trichur Vidyasagar1*, Ekaterina Levichkina1 and Yuri Saalmann2 1 University of Melbourne, Optometry & Vision Sciences, Australia 2 University of Wisconsin – Madison, Psychology, United States Introduction: Lateral intraparietal cortex (LIP), a part of posterior parietal cortex, is known to be involved in top-down modulation of responses to visual stimuli at earlier stages of the visual pathway1. Many of its neurons show enhancement of responses for stimuli at attended locations and many also show selectivity to the stimulus orientation1. We investigated whether there is a relationship between these two properties in LIP cells, since it has important implications for models of selective attention and the binding problem2. Methods: Two macaques were trained on a delayed match to sample task. They had to match both the location and orientation of two gratings presented with 800 ms delay between them. We measured orientation selectivity of 56 cells in LIP and also the degree of the attentional enhancement in both correct and error trials. Results: Orientation selectivity and attentional enhancement both varied considerably between LIP neurons. However, the cells (N = 25) with significant attentional enhancement (ratio of response to the second presentation of a stimulus at the same location as the first to that of the response to the first stimulus) have significantly lower orientation selectivity (Wilcoxon T-test, p<0.05). Furthermore, the population of attention-selective cells showed around 35% enhancement in correct match trials but only 27% in error trials (Wilcoxon T-test, for the group of 16 cells from sessions with sufficient errors, p<0.05). Conclusion: The results indicate that LIP may be a priority map where salient or preferred spatial locations are selected for further processing, but consequent to a first stage of selection that is sensitive to feature-sensitive inputs. Such an attentional mechanism is ideally suited for detecting targets as in the 2-stage Guided Search model2,3. 1Saalmann YB et al. (2007) Science, 316:1625. 2Vidyasagar TR (1999) Brain Res Rev., 30,66. 3Wolfe JM (1994) Psychonomic Bull. 15, 419. Keywords: macaque, spatial attention, parietal cortex, feature selectivity, guided search Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Attention Citation: Vidyasagar T, Levichkina E and Saalmann Y (2015). Coding dichotomy in lateral intraparietal cortex (LIP) of the macaque monkey and its role in spatial attention. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00381 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: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Prof. Trichur Vidyasagar, University of Melbourne, Optometry & Vision Sciences, Melbourne, Australia, trv@unimelb.edu.au 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 Trichur Vidyasagar Ekaterina Levichkina Yuri Saalmann Google Trichur Vidyasagar Ekaterina Levichkina Yuri Saalmann Google Scholar Trichur Vidyasagar Ekaterina Levichkina Yuri Saalmann PubMed Trichur Vidyasagar Ekaterina Levichkina Yuri Saalmann 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.