Psychophysical Methods

When Fechner (1860/1966) introduced the new transdisciplinary research program of “Psychophysik”, his goal was to present a scientific method of studying the relations between body and mind, or, to put it more precisely, between the physical and phenomenal worlds. The key idea underlying Fechner’s psychophysics was that body and mind are just different reflections of the same reality. From an external, objective viewpoint we speak of processes in the brain (i.e., of bodily processes). Considering the same processes from an internalized, subjective viewpoint, we can speak of processes of the mind. In suggesting that processes of the brain are directly reflected in processes of the mind, Fechner anticipated one of the main goals of modern neuroscience, which is to establish correlations between neuronal (objective) and perceptual (subjective) events. The goal of this chapter is to present Fechner’s techniques and those extensions and modifications of psychophysical methods that may be helpful to the modern neuroscientist with the time-honored objective of discovering the properties of mind and their relation to the brain.