Cognitive Science

Discs avec Spriales — Marcel Duchamp.

In a nutshell: I am simply in love with cognitive science.

I have become interested in the problems of cognitive sciences before I’ve entered the Department of Psychology at the University of Belgrade. In 1992/93, I studied mathematics, interested mostly in logic and foundational problems (say, philosophy of mathematics). And before that, back in high school, I was devoted to computer science, making my first steps in science in the Petnica Research Center, together with many great (and crazy) guys. Under such influences, I already learned something about research in the area of artificial intelligence. What had happened when I turned to psychology is that I have realized how my background in natural sciences and math was nicely suited to deal with problems of cognitive psychology. I already knew something about formal systems and was able to quickly grasp the writings of Fodor, Chomsky and other influential authors in cognitive science; I was also motivated to learn about connectionism and probabilistic approaches (rational Bayesian modeling is currently my preferred methodology) . I learned all that I needed to know about experimental methodology in the Laboratory for Experimental Psychology at our Department and very soon started doing research on my own. The support of my professors - Predrag Ognjenović, whose lectures helped me understand psychophysics and introduced me to experimental psychology in general, visual scientist Dejan Todorović, and experimental psycholinguist Aleksandar Kostić was of invaluable help to me.

My research interests in cognitive science are roughly grouped in three areas: (a) concepts, meaning and categorization, (b) causality and causal learning and (c) choice under risk and uncertainty. Methodologically, I develop Bayesian probabilistic models of human behaviour, generally working in the framework of rational analysis of cognition, but I am also very critical of this methodological approach: my PhD thesis (currently working on it) presents a critical examination of the rationality debate and questions the validity of rational analysis.

In the field of concepts, categorization and semantics I have mostly focused on the study of geometrical and probabilistic representation of semantic structures. Experimentally, I have mostly worked on models of similarity scaling and sentence verification. I am interested in how people represent the meaning and categorize ecologically relevant verbal conceptual stimuli, in sharp contrast with the tradition in the field of category learning where most experimental tasks are carried on with simple and artificial schematic visual stimuli. I have had the pleasure to work two years in Gregory Murphy’s lab on NYU and study category learning there.

I have learned about the field of causality and causal learning (causal induction) during my first two years of PhD studies at the New York University, USA, from prof. Bob Rehder. Bob and I have worked together on a Bayesian model of causal belief revision, exploring the interaction between the representation of theoretical causal information (causal structures, or causal networks) and the empirical, covariation data presented to our subjects. You can learn more about our results from http://csjarchive.cogsci.rpi.edu/proceedings/2007/docs/p1843.pdf

A few years ago, I have started developing models and measurements of monetary equivalents in the field of choice under risk and uncertainty. Some of the findings are summarized in the abstract of the lecture I gave in May 2009. on a new mathematical theory of human choice under risk, the Confidence theory. I still have a plenty of experimental work to do here (choice experiments, or gamble tasks if you prefer; these tasks are as useful as they are boring for both the programmer and the human subject) and I expect the future work in this field to bring me many exciting moments.

I am currently writing up my my PhD Thesis, which is of both a theoretical and experimental character, with the goal to provide an as thorough as possible analysis of the way we use and understand the concept of rationality in contemporary cognitive psychology. The motivation for this work lies in my interest in the rationality debate, namely: I am trying to figure out whether one can develop a coherent set of criteria according to which one can decide upon the validity of normative vs. descriptive models in those fields of psychology where exact mathematical models are used to model and predict human behavior. My thesis advisor is prof. Gordana Jovanović, Department of Psychology, Faculty of Philosophy, University of Belgrade.