#79 Karl Friston: The Origins of SPM and the Making of Modern Human Brain Mapping

Karl Friston is one of the most influential neuroscientists of our time and a central figure in the history of human brain mapping. Many listeners will know him for the free energy principle, active inference, dynamic causal modeling, voxel-based morphometry, and many other theoretical contributions.In this episode, we take a different route and go back to the early history of Statistical Parametric Mapping, or SPM: the software and statistical framework that helped turn functional neuroimaging from a local craft into a shared scientific language.We discuss how Karl moved from psychiatry into brain imaging, what the first PET activation experiments felt like, how SPM emerged at the MRC Cyclotron Unit and later the Functional Imaging Laboratory, how the software spread through the neuroimaging community, and how key collaborators helped shape modern PET, fMRI, VBM, DCM, EEG, and MEG analysis.We also talk about mentorship, the culture of the FIL, open software, MNI space, spatial normalization, and what it means for a scientific tool to become infrastructure for an entire field.