John Duncan

University of Cambridge, UK
Thought, intelligence and the brain

Educated at the University of Oxford (1970-1976), John Duncan spent two years at the University of Oregon working with Michael Posner before taking up a research position with the Medical Research Council. Currently he is a Programme Leader at the MRC Cognition and Brain Sciences Unit, University of Cambridge, with an adjunct appointment at the University of Oxford.  Trained in cognitive psychology and physiology, he now has research programmes in neuropsychology, neuroimaging, and single cell electrophysiology, addressing problems of attention, intelligence, cognitive control, impairment and recovery following brain damage, and frontal lobe functions.  He is a Fellow of the Royal Society and the British Academy, and winner of the 2012 Heineken Prize in Cognitive Science.

Thought, intelligence and the brain

Simple tests of problem solving – often called tests of “intelligence” – measure something of vital importance in our mental lives. People who solve these problems easily do better in education, earn better salaries, have better mental health and live longer. So what cognitive and brain functions are measured in simple problem solving? Recent experiments show the central importance of selective attention – focusing on simple, solvable sub-problems within a complex whole. Brain imaging experiments relate attention to a specific brain network, whose widely distributed parts communicate closely to construct mental operations, and in patients with damage to this network, individual aspects of cognition such as perception, memory, speech and movement are intact, but cannot be combined into coherent, organized mental programs. Single neurons in the network themselves “attend”, changing their properties to encode just the information needed in current thought and behaviour. Putting together experimental psychology, brain imaging, neurophysiology and computer science, we begin to see how it is that the brain constructs organized, “intelligent” mental activity.