John Duncan has focused on the psychological abilities in which humans excel — such as selective attention and intelligent decision-making — and developed explanatory theories based on underlying brain activity. His ideas extend from patterns of firing in individual neurons to patterns of human behaviour.

He has examined our capacity to pay attention to some features of our environment and ignore others, leading to selective conscious awareness. He has also identified a brain system in the frontal and parietal lobes that organises intelligent, goal-directed thought and behaviour.

John is the author of How Intelligence Happens (2010), a popular book that asks how human brains can do much more than the brains of other mammals with the same basic components. He was elected a Fellow of the British Academy in 2009, and won the 2012 Heineken Prize for Cognitive Science.