Robert Whytt

Robert Whytt (1714–1766) was a Scottish physician. His work, on unconscious reflexes, tubercular meningitis, urinary bladder stones, and hysteria, is remembered now most for his book on diseases of the nervous system. He served as President of the Royal College of Physicians of Edinburgh.

The second son of Robert Whytt of Bennochy (near Kirkcaldy in Fife), advocate, and Jean, daughter of Antony Murray of Woodend, Perthshire, he was born in Edinburgh on 6 September 1714, six months after his father's death. Having graduated M.A. at the University of St Andrews in 1730, he went to Edinburgh to study medicine. Two years before this he had succeeded, on the death of his elder brother George, to the family estate.

Whytt devoted himself to the study of anatomy, under the first Monro. Going to London in 1734, Whytt became a pupil of William Cheselden, while he visited the wards of the London hospitals. After this he attended the lectures of Jacob B. Winslow in Paris, of Herman Boerhaave and Bernhard Siegfried Albinus at Leyden. He took the degree of M.D. at Reims on 2 April 1736. On 3 June 1737, a similar degree was conferred on him by the University of St Andrews, and on 21 June he became a licentiate of the Royal College of Physicians of Edinburgh. On 27 November 1738, he was elected to the fellowship, and began practice as a physician.

On 26 August 1747, Whytt was appointed professor of the theory of medicine in Edinburgh University. On 16 April 1752 Whytt was elected Fellow of the Royal Society of London, and contributed to the Philosophical Transactions. In 1756 he gave lectures on chemistry in the university in place of John Rutherford (1695–1779). In 1761 Whytt was made first physician to King George III in Scotland—a post specially created for him—and on 1 December 1763 he was elected president of the Royal College of Physicians of Edinburgh; he held the presidency till his death at Edinburgh on 15 April 1766 at age 52.

His remains were given a public funeral, and were interred in a private vault (built two years earlier) in the now sealed section of Greyfriars Kirkyard known as the Covenanter's Prison.

Robert Whytt is one of the most accomplished neurophysiologists of his time. In his research, he outlined the significance of the central nervous system on movement, drew distinctions between voluntary and involuntary actions and clarified the components of the light reflex within the eye.

Whytt's theories on the nervous system and its role in movement opposed many of the teachings that were in place in the 18th century. During that time, many physiologists still supported Descartes' theory of movement which hypothesized that muscle contraction was due to the activation of fluid in the nervous system called animal spirits. Physiologists, such as Whytt's colleague, Albrecht von Haller, also believed that muscles were capable of action independent of the nerves. Whytt strongly advocated against Descartes' theory, and explicitly denied the concept of animal spirits. Furthermore, he rejected Haller's theory by claiming that movement must depend on interconnecting nerves that lead to the brain or spinal cord.

Whytt decided to prove his theory through experimentation. He replicated Stephen Hales' experiment that consisted of probing and examining the response of limbs in decapitated frogs. In Whytt's version of the experiment, he inserted a hot wire through the spine of the decapitated frog and observed that when the spine of the frog was destroyed, no form of pricking or cutting of the frog's limb elicited a response. If the frog's spine stayed intact as it did in Hales' experiment, the limbs continued to respond to the pricking and cutting. Additionally, Whytt tested to see if a response could still be created if certain sections of the spinal cord remained intact. The results show that as long as the spinal cord is partially undamaged, small responses in the limbs can still be produced.