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Ubi irritatio, ibi affluxus: a 19th century perspective on haemodynamic brain activity
Roland Pfister1, Katharina A Schwarz, Markus Janczyk
1Julius-Maximilians University of Würzburg, Department of Psychology III, Germany. roland.pfister@psychologie.uni-wuerzburg.de
Abstract:
The impact of cognitive operations on haemodynamic activity in the human brain is a cornerstone of modern cognitive neuroscience. This essay presents an early speculation about why there is increased blood flow following cognitive operations: Emil Harleß, a 19th century German physiologist, proposed that this blood flow responds to irritations caused by "the will" in order to restore homeostasis. Peculiar from a modern perspective, this speculation shows how neuroscientific concepts - and corresponding perspectives on cognitive function - have changed over the centuries.

