Abstract
Yves Delage (1854-1920) is known mostly as a French zoologist who made key dis coveries on the physiology and embryology of marine animals and who was director of the Roscoff Biological Station. Upon becoming blind in his late 50s, Delage dedicated himself to introspective analysis of consciousness and published shortly before his death a volume in which he espoused his associational theory of dreams, which attacked di rectly Freud's ideas. At the heart of Delage's theory is the hypothesis of "parachroni zation of neuronal vibratory modes." He envisioned each neuron having a characteristic vibratory mode, which can be impinged on neighboring neurons according to the strength of their interaction, causing an ensemble of neurons to vibrate in synchrony. He also envisioned strengthening of interactions among simultaneously active neurons, antici pating Hebb's principle. As a result, the properties represented by the synchronized neu rons coalesce, and are perceived together "as a single idea." Their own engagement in synchronization leaves on the physical connections among them a trace, a "relic," that facilitates their future parachronization. He thus explained perception, association of ideas in trains of thought and in dreams, learning, and memory, decades before the necessary tools became available for neuroscientists to tackle these questions experi mentally. Delage's contribution to neuroscience, through his cunning vision on these issues, anticipated by 70 years the discovery that neuronal synchronous oscillations are associated with perception, dreaming, and memory. NEUROSCIENTIST 5:341-345, 1999