On the energy cost of mental effort

The discovery of the Law of Conservation of Energy in the 1840s had consequences for psychological theory. Does the process of thinking involve a novel form of energy that is not recognized by physical science? E. L. Youmans (1821-1887) argued that "mental operations are dependent upon material changes in the nervous system." Kurd Lasswitz (1848-1910) introduced the term "psychophysical energy," based upon the electrical activity of the brain. At the beginning of the twentieth century Alfred Lehmann (1858-1921) claimed that intense mental effort leads to a net increase in oxygen utilization and regarded this as evidence of a specific psychic energy. His views were adopted and extended by Hans Berger (1873-1941). F. G. Benedict (1870-1957), drawing upon extensive experience with balance experiments conducted on humans in large-scale respiration calorimeters, concluded that mental effort probably had no effect upon the brain's metabolism. Modern approaches to the problem make use of PET imaging, which detects local changes in glucose utilization by the brain during cognitive activity.     

Neuroscience in the Nobel perspective

The Nobel Prizes for Physiology or Medicine have included a relatively large number of awards for work in the neurosciences, or for work construed to have made a contribution to neuroscience. These are recognized in this article by brief explanations of the particular contribution that warranted this magnificent (and munificent) award. The first prizes in neuroscience were awarded five years after the initiation of the Nobel Foundation's program. Up to 2005, 28 prizes have been awarded for achievements in neuroscience to 52 individuals.