May-Britt Moser (born January 4, 1963, Fosnavåg, Norway) is a Norwegian neuroscientist who contributed to the discovery of grid cells in the brain and the elucidation of their role in generating a system of mental coordinates by which animals are able to navigate their environment. Moser’s work enabled scientists to gain new insight into cognitive processes (such as memory) and spatial deficits associated with human neurological conditions such as Alzheimer disease. For her discoveries concerning the neural systems that underlie spatial representation in the mammalian brain, she was awarded the 2014 Nobel Prize for Physiology or Medicine, which she shared with her husband, Norwegian neuroscientist Edvard I. Moser, and with British-American neuroscientist John O’Keefe. The Mosers were the fifth married couple to share a Nobel Prize.
May-Britt grew up on a farm in the remote western region of Norway. In the early 1980s she attended the University of Oslo, where she studied multiple subjects, including mathematics, neurobiology, and psychology. She married Edvard in 1985, and together they decided to pursue the study of brain-behaviour relationships. In the early 1990s May-Britt undertook graduate studies at Oslo, working alongside her husband in the laboratory of Norwegian researcher Per Oskar Andersen. She investigated correlations between the anatomical structure of the hippocampus and spatial learning in rats, work that culminated in a doctorate degree in neurophysiology in 1995. Over the course of the next year, she and Edvard traveled to the University of Edinburgh to study with British neuroscientist Richard Morris and to University College London, where they spent time in O’Keefe’s laboratory. In 1996 May-Britt accepted an assistant professorship at the Norwegian University of Science and Technology (NTNU), where Edvard also had been offered a position. Both were later made full professors at NTNU.
The Mosers investigated the neural networks of the hippocampus, attempting to identify the mechanism underlying the generation of cortical (spatial) maps. They began by examining the effects of hippocampal lesions on the activity of place cells, which had been reported by O’Keefe and his student Jonathan O. Dostrovsky in 1971 to function in cortical mapping. The Mosers’ observations drew their attention to a part of the brain known as the entorhinal cortex, which shared direct connections with CA1, an area of the hippocampus that O’Keefe and Dostrovsky had shown to play a key role in spatial processing. With the assistance of Dutch functional neuroanatomist Menno P. Witter, the Mosers were able to precisely place electrodes in the dorsocaudal medial entorhinal cortex (dMEC) of the rat brain, allowing them to record the activity of cells in response to specific behaviours. Similar to O’Keefe’s findings with place cells, the Mosers found that cells in the dMEC became active in relation to an animal’s position in its environment. But, unlike the activity of place cells, the activity of the cells that the Mosers observed occurred in a strikingly regular pattern: as rats ran freely in their enclosures, spikes of activity at each electrode were not only evenly spaced but also similar in direction and size. The regular activity formed a grid of equilateral, tessellating triangles, as revealed by spatial analyses, which inspired the name grid cell.
In later work, the Mosers discovered additional cells in the dMEC that signaled spatial information, including head direction cells, which fired preferentially in response to an animal’s head direction, and border cells, which transmitted information about the boundaries of an animal’s environment. They also found that grid cells, head direction cells, and border cells interacted with place cells in the hippocampus to determine orientation and navigation. The spatial representation system was described as an “inner GPS.”
May-Britt was a founding codirector, with Edvard, of the Kavli Institute for Systems Neuroscience in 2007 and the Centre for Neural Computation in 2013, both at NTNU. She was a recipient of multiple awards, notably the 2013 Louisa Gross Horwitz Prize for Biology or Biochemistry (shared with Edvard and O’Keefe), in addition to the Nobel Prize.