Objective The perception of complex visual scenes requires active processing by the brain. The visual cortex is hierarchically organized in several areas which are linked by connections projecting from lower to higher areas (feedforward) and connections projecting from higher to lower areas (feedback). More complicated processing occurs in higher areas such as V4, where neurons encode which side of a border belongs to a figure. Feedback connections are large in number but their function is poorly understood. An important role for feedback has been proposed in probabilistic inference, whereby cortical areas “infer” the reality in the external world based on the sensory information they receive from lower areas, combined with prior hypotheses projected down from higher areas. In this project we propose a causal study of the role of feedback connections from area V4 to lower areas in the inference of figure location. We will record neural activity simultaneously in V4 and V1, and V4 and V2, using microelectrodes in the awake rhesus macaque, during the presentation of figures on a background, while we reversible activate or suppress a well-defined patch in V4 using an opsin. By training the animal to perform a figure detection task we can link the perturbation of neural activity to perception.The beneficiary is the Netherlands Institute for Neuroscience, where the researcher will be advised by Prof. Pieter Roelfsema, an internationally recognized expert in visual neuroscience with experience with neurophysiology, behavioral studies and computational neuroscience. There will be an outgoing phase of two years, during which the researcher will perform animal experiments in the laboratory of Prof. John Reynolds in the Salk Institute for Biological Studies, who has extensive experience with optogenetics and viral targeting. Fields of science social sciencespsychologybehavioural psychologynatural sciencesbiological sciencesneurobiologycomputational neuroscience Keywords feedback optogenetics visual border-ownership Programme(s) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Topic(s) MSCA-IF-2016 - Individual Fellowships Call for proposal H2020-MSCA-IF-2016 See other projects for this call Funding Scheme MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF) Coordinator KONINKLIJKE NEDERLANDSE AKADEMIE VAN WETENSCHAPPEN - KNAW Net EU contribution € 242 929,80 Address Kloveniersburgwal 29 het trippenhuis 1011 JV Amsterdam Netherlands See on map Region West-Nederland Noord-Holland Groot-Amsterdam Activity type Other Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 0,00 Partners (1) Sort alphabetically Sort by Net EU contribution Expand all Collapse all Partner Partner organisations contribute to the implementation of the action, but do not sign the Grant Agreement. THE SALK INSTITUTE FOR BIOLOGICAL STUDIES United States Net EU contribution € 0,00 Address North torrey pines road 10010 92037 La jolla See on map Activity type Research Organisations Links Contact the organisation Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Other funding € 160 130,40