endured years of tedious exertion, squinting over the eyepiece of his
microscope, encapsulating the landscapes of our microscopic constitution.
He was, and will always be, the greatest cartographer of the mind.
Edward Evarts (1926–1985) was born in New York City and attended
both Harvard College and Harvard Medical School, earning his MD in
- He immediately began a life of psychoneurological investigation,
briefly completing two years of psychiatric training before returning to the
neurophysiology laboratory at the National Institute of Mental Health
(NIMH) in Bethesda, Maryland, for more than three decades. Evarts spent
his professional career delving into the functional pathways of the brain,
but instead of relying upon the histological staining of dead brain matter,
innovated a way of testing the electrical transmissions of the brain. His
patients were not humans with psychological problems, but a small
number of cats and monkeys.
Evarts made several breakthrough discoveries in the 1960s, particularly
in inventing a way of tracking single cortical neurons in animals. In 1962
and 1964, Evarts published articles detailing the use of glass-insulated
platinum-iridium microelectrodes in unanesthetized, unrestrained cats^14
and monkeys,^15 respectively, in their waking and sleeping states. Later,
Evarts was able to track activity of single neurons during operantly
conditioned movements in monkeys.^16 These studies were based on
decades of research by trailblazing neurophysiologists, following the
predictable pattern seen in every branch of medicine: anatomy, physiology,
and eventually, pathology. Evarts wasn’t the first to use implantable
electrodes in lab animals, but his own “brilliant perfection of the method
of single unit recording”^17 led to its widespread use, and potentiated the
ability to track even more complex circuitry in the brain.
Evarts’ ultimate goal was understanding the physical basis of mental
activity, but concluded that the initial program would be to comprehend
the patterns of firing during limb movement. He held that “one must
understand movement before one can understand the mind behind it.”^18
Evarts was able to decode the timing and sequencing of neural firing over
the next two decades, but in addition to his lab techniques, his greatest
contribution to neurophysiology was his mentorship of leading
neuroscientists, including a young Harvard medical resident who was
doomed to be shipped to the theater of war in Vietnam if he didn’t find a