How to breathe life back into brain theory

The Brain, In Theory Romain Brette Princeton Univ. Press (2026) What is a brain? The question might seem obvious, but it is not trivial. Neuroscience has progressed in the past century, with the development of sophisticated techniques to measure and manipulate brain cells, neural circuits and even animal behaviours . Yet how the brain actually works still eludes us. In The Brain, In Theory , neuroscientist Romain Brette deconstructs the predominant model of the brain, which treats the organ like a computer. He concedes that engineering metaphors can be useful but argues that they are often vague, incoherent and misleading — failing to capture animal cognition, for example. The reason is simple: real brains are not engineered. Brette aims to breathe life back into brain science by focusing the study of the nervous system on biology. The task is daunting, but Brette’s take-down of the field’s dominant theoretical frameworks is systematic. Faulty thinking First, he tackles the idea that brains and life in general can be explained using mechanistic concepts. Brains are not programmable machines, Brette contends, because neurons do not follow fixed rules or commands, cannot be modified to function arbitrarily and don’t implement computations as such. Nor is neural activity a code, in which one variable is mapped directly to another (as happens in Morse code and Braille). …