The primary research focus of Dr. Morris is on developing a neurobiological account of the functions of the hippocampal formation in memory. No brain structure works in isolation and the hippocampus is no exception, with much of his present focus being on the impact of subcortical neuromodulatory inputs on memory encoding and consolidation, and on hippocampal cortical interactions in systems consolidation. NMDA receptor-dependent synaptic plasticity is shown to be critical for the encoding and intermediate storage of memory traces in this task, while AMPA receptor-mediated fast synaptic transmission is necessary for memory retrieval. Typically, these rapidly encoded traces decay quite rapidly over time. Synaptic potentiation also decays rapidly, but can be rendered more persistent by a process of cellular consolidation in which synaptic tagging and capture play a key part in determining whether or not it will be persistent. Synaptic tags set at the time of an event, even many trivial events, can capture the products of the synthesis of plasticity proteins set in train by events before, during or even after an event to be remembered. Tag-protein interactions stabilize synaptic potentiation and, by implication, memory. The behavioral implications of tagging are explored. Using a different protocol for flavor-place paired associate learning, it is shown that rats can develop a spatial schema which represents the relative locations of several different flavors of food hidden at places within a familiar space. This schema is learned gradually but, once acquired, enables new paired associates to be encoded and stored in one trial. Their incorporation into the schema prevents rapid forgetting and suggests that schema play a key and hitherto unappreciated role in systems-level memory consolidation. The elements of what may eventually mature into a more formal neurobiological theory of hippocampal memory are laid out as specific propositions with detailed conceptual discussion and reference to recent data.

Dr. Morris is Professor of Neuroscience at the University of Edinburgh and Head of Neuroscience and Mental Health at the Wellcome Trust. He has a degree in Natural Sciences from the University of Cambridge and a D.Phil from the University of Sussex. He has been active in public awareness of science activities throughout his career, including helping to write a neuroscience booklet distributed to all secondary schools in the UK. His principal research interest is in the neurobiology of learning and memory and he has published over 100 articles and 3 edited books in the field. His main academic contributions have included the development of the open-field Watermaze, a behavioral task for rodents that is now used worldwide.

Selected Publications:

Tse, D., Langston, R.F., Kakeyama, M., Bethus, I., Spooner, P.A., Wood, E.R., Witter, M.P., and Morris, R.G. (2007) Schemas and memory consolidation. Science 316, 76-82.

O'Carroll, C.M., Martin, S.J., Sandin, J., Frenguelli, B., and Morris, R.G. (2006) Dopaminergic modulation of the persistence of one-trial hippocampus-dependent memory. Learn Mem. 13, 760-769.

Morris, R.G. (2006) Elements of a neurobiological theory of hippocampal function: the role of synaptic plasticity, synaptic tagging and schemas. Eur J Neurosci. 23, 2829-2846.

For more information - http://neuroseries.info.nih.gov