Mircea Steriade (August 20, 1924 – April 14, 2006), MD, DSc, was a prominent researcher in

systems neuroscience Systems neuroscience is a subdiscipline of neuroscience and systems biology that studies the structure and function of various neural circuits and systems that make up the central nervous system of an organism. Systems neuroscience encompasses a n ...

. He was born in

Bucharest Bucharest ( , ; ) is the capital and largest city of Romania. The metropolis stands on the River Dâmbovița (river), Dâmbovița in south-eastern Romania. Its population is officially estimated at 1.76 million residents within a greater Buc ...

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

, and studied

medicine Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

University of Bucharest The University of Bucharest (UB) () is a public university, public research university in Bucharest, Romania. It was founded in its current form on by a decree of Prince Alexandru Ioan Cuza to convert the former Princely Academy of Bucharest, P ...

. He emigrated to

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

in 1968, where he became a professor of

physiology Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ syst ...

Université Laval (; English: ''Laval University)'' is a public research university in Quebec City, Quebec, Canada. The university traces its roots to the Séminaire de Québec, founded by François de Montmorency-Laval in 1663, making it the oldest institutio ...

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

, a position he held for the rest of his life. He is the father of linguist,

Donca Steriade Donca Steriade (born 1951 in Bucharest) is a Romanian-American professor of Linguistics at MIT, specializing in phonological theory. Education She began her academic career studying classics in Bucharest, after earning her B.A. (''licență'') i ...

Research

While at Laval University, he discovered that the slow oscillations of NREM sleep arise when groups of

neuron A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...

s fire together for a little while (so-called "on periods"), then fall silent for about a fraction of a second ("off periods"), and then resume their synchronized firing. This was one of the fundamental discoveries in sleep research. After his discovery, scientists have also discovered that in birds and mammals, the slow waves are large if preceded by a long period of wakefulness and become smaller as sleep goes on. The majority of his research was on corticothalamic

oscillations Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples of oscillation include a swinging pendulum ...

. He was among the first to study the dynamics of the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

during sleep, and one of his key discoveries was determining the role of thalamic reticular neurons as pacemakers in producing the

sleep spindle Sleep spindles are bursts of neural oscillatory activity that are generated by interplay of the thalamic reticular nucleus (TRN) and other thalamic nuclei during stage 2 NREM sleep in a frequency range of ~11 to 16 Hz (usually 12–14&nbs ...

rhythm. He also discovered slow (<1 Hz) sleep rhythms associated with intracortical activity.

Honors

In 1998 he was the recipient of the Gloor-Award (American Clinical Neurophysiology Society).

References

Nature obituarySociety for Neuroscience obituaryNew Hypothesis Explains Why We Sleep (published in Scientific American)
Romanian emigrants to Canada 1924 births 2006 deaths University of Bucharest alumni Academic staff of Université Laval {{Romania-med-bio-stub