Model-based spatio-temporal dynamics Running Title: Model-based spatio-temporal dynamics Computational EEG Modelling of Decision Making Under Ambiguity Reveals Spatio- Temporal Dynamics of Outcome Evaluation Lee Jollans 1* , Robert Whelan 1* , Louise Venables 2 , Oliver H. Turnbull 3 , Matteo Cella 2,4 and Simon Dymond† 2,5 1 School of Psychology, Trinity College Dublin, Dublin 2, Ireland. 2 Department of Psychology, Swansea University, Singleton Campus, Swansea SA2 8PP, United Kingdom (s.o.dymond@swansea.ac.uk ). 3 School of Psychology, Bangor University, Bangor, Gwynedd, LL57 2DG, United Kingdom. 4 Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, De Crespigny Park, SE5 8AF, London, United Kingdom. 5 Department of Psychology, Reykjavík University, Menntavegur 1, Nauthólsvík, 101 Reykjavík, Iceland. † Corresponding author *Equal contribution 1