Probable evolutionary relationship of serotonin and the plant growth hormone indoleacetic acid/auxin
pp. 99-102 of D. W. Woolley’s The Biochemical Bases of Psychoses
In an article titled D. W. Woolley, the Serotonin Hypothesis and the Genesis of Psychopharmacology, I wrote that Woolley “believed serotonin played a role in brain development because of its resemblance to auxin (a plant hormone that stimulates cell growth and orients it toward sources of energy) and was the first to propose that serotonin dysfunctions interfered with learning and memory.”
Below is a digitized section from my copy of Woolley’s 1962 book, ‘The Biochemical Bases of Psychoses – or the Serotonin Hypothesis about Mental Disease.‘ In these pages, taken from “Chapter 4 – Serotonin,” he documents a few structural and functional similarities between serotonin in animals and auxin in plants, and traces its evolutionary lineage back to our earliest ancestors.
This recognition is reflected in and expanded on in much greater scope and detail in the modern work of Dr. Efrain C. Azmitia, a Rockefeller neuroscientist and professor of biology and neural science at New York University. And it is with the help of Azmitia’s work that I conceived of and wrote Psychedelotropism, which can be considered in basic terms a research-based reflection on psychedelic experience from an understanding of the serotonin system supported by the biological parallel of auxin in plant tropisms.
-E. M. Fortier