Contributions of Professor Samuel J. Williamson to biomagnetism research

Samuel J. Williamson, University Professor of Physics, New York University, left us at the early age of 65 on April 25, 2005 due to complications from Alzheimer's disease. He was one of the principal pioneers of biomagnetism research, working with his close colleague and partner Lloyd Kaufman, Professor of Psychology at NYU. Sam developed one of the first biomagnetometers together with Douglas Brenner. Sam along with his colleagues successfully made first recordings of magnetoencephalography (MEG) signals from the visual, somatosensory and motor cortices and later identified a tonotopic mapping in the auditory cortex. He also helped develop multi-channel and whole-head MEG systems and a new type of biomagnetometer called cryoSQUID. Sam popularized the current dipole analysis approach to interpret MEG signals and pioneered the concept of magnetic source imaging (MSI), which combines anatomical Magnetic Resonance Imaging (MRI) and MEG. He also made contributions to the area of liver and lung susceptometry. Sam was perhaps the most effective ambassador in our field of biomagnetism research, helping to strengthen cooperation among researchers within our field and also serving to promote this new research area to the rest of scientific community.