Pioneers of affective neuroscience and early concepts of the emotional brain.

Views on the representation of emotion in the brain, as formulated about a century ago, are described, with a focus on the Vienna physiologist and psychologist Sigmund Exner, the psychoanalyst Sigmund Freud, and the French physician Israel Waynbaum. All three can be characterized as forerunners in the field of "affective neuroscience". By the turn of the century, they had developed a neural network theory of emotion which included a stage of pre-cortical processing. In spite of their otherwise very diverse theoretical backgrounds, their concepts of parallel processing routes were highly similar. It is interesting to note that their ideas were on line with present-day views on the neural substrates and physiological characteristics of emotional processing, although none of the three scientists could rely on the refined anatomical knowledge available nowadays.