20 February, 2015

JOHN O' Keefe (Neuroscientist)


              John O'Keefe (neuroscientist)






Born
(1939-11-18) 18 November 1939 (age 75)
New York City
Citizenship
·         United States
·         United Kingdom
Fields
Institutions
·         City College of New York (B.A., 1963)
·         McGill University (M.A, 1964; Ph.D., 1967)
Known for
Discovering place cells
Notable awards
·         Kavli Prize in Neuroscience (2014)
·         Nobel Prize in Physiology or Medicine (2014)













John O'Keefe, FRS FMedSci (born 18 November 1939) is an American-British neuroscientist and a professor at the Institute of Cognitive Neuroscience and the Department of Anatomy at University College London. He is known for his discovery of place cells in the hippocampus and his discovery that they show a specific kind of temporal coding in the form of theta phase precession. In 2014, he received the Kavli Prize in Neuroscience "for the discovery of specialized brain networks for memory and cognition", together with Brenda Milner and Marcus Raichle. He shared the Nobel Prize in Physiology or Medicine in 2014 together with May-Britt Moser and Edvard Moser.

Biography
Born in New York City to Irish immigrant parents, O'Keefe attended Regis High School (Manhattan) and received a BA degree from the City College of New York. He went on to study at McGill University in Montreal, where he obtained an MA degree in 1964, and a PhD degree in Donald Hebb's Department of Psychology in 1967, supervised by Ronald Melzack. He originally went to University College London in 1967 as a US NIMH postdoctoral fellow working with the late Patrick Wall. He has been there ever since, and was awarded a professorship in 1987. He is a citizen of both the United States and the United Kingdom.

Discovery of place cells

O’Keefe and his student Jonathan Dostrovsky discovered place cells by systematically analyzing the environmental factors influencing the firing properties of individual hippocampal neurons. His many publications on place cells have been highly cited. In addition, he published an influential book with Lynn Nadel, proposing the functional role of the hippocampus as a cognitive map for spatial memory function. In extensions of his work, place cells have been analyzed experimentally or simulated in models in hundreds of papers.

Discovery of theta phase precession
In further research on place cells, O’Keefe found evidence for a distinctive variation of temporal coding of information by the timing of action potentials in place cells, relative to an oscillatory EEG cycle known as the theta rhythm, as opposed to spike timing within a single cell. In a 1993 paper, he and Michael Recce demonstrated that place cells spike at different phases relative to theta rhythm oscillations in the local field potential of the hippocampus. As a rat enters the firing field of a place cell, the spiking starts at late phases of theta rhythm, and as the rat moves through the firing field, the spikes shift to earlier phases of the theta cycle. This effect has been replicated in numerous subsequent papers, providing evidence for the coding of sensory input by the timing of spikes. Numerous models have addressed the potential physiological mechanisms of theta phase precession.

Prediction and discovery of boundary vector cell
In a paper in 1996, O'Keefe and Neil Burgess presented data showing shifts in the position and size of place cell firing fields when the barriers defining the environment were shifted. In this and subsequent papers, they presented a model of this phenomenon predicting the existence of boundary vector cells that would respond at a specific distance from barriers in the environment. Several years later, this explicit theoretical prediction was supported by extensive experimental data demonstrating boundary cells with the predicted properties in the subiculum and the medial entorhinal cortex (where they are sometimes referred to as border cells).

Recent awards and positions

He is a Fellow of the Royal Society and of the U.K. Academy of Medical Sciences. In addition, he received the Feldberg Foundation Prize in 2001 and the Grawemeyer Award in psychology in 2006 (with Lynn Nadel). In 2007, he received the British Neuroscience Association Award for Outstanding Contribution to British Neuroscience and in 2008 he received the Federation of European Neuroscience Societies European Journal of Neuroscience Award. Later in 2008, O'Keefe was awarded the Gruber Prize in Neuroscience. He was appointed as the inaugural director of the Sainsbury Wellcome Centre for Neural Cuits and Behavior. In 2013 he received the Louisa Gross Horwitz Prize (with Edvard Moser and May-Britt Moser). In 2014, he was a co-recipient of the Kavli Prize awarded by the Norwegian Academy of Science and Letters with Brenda Milner and Marcus Raichle.
Further, he was awarded one half of the Nobel Prize in Physiology or Medicine 2014, with the other half going to May-Britt Moser and Edvard Moser.[21]
O'Keefe received an honorary Doctor of Science degree from University College Cork on 15 December 2014.



Posted By:- Shilpa D. Sanap (Roll No. 74)


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