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The role of the GluR−A (GluR1) AMPA receptor subunit in learning and memory

School of Psychology, Cardiff University, Tower Building, Park Place, PO Box 901, Cardiff, CF10 3YG, UK
Progress in brain research (Impact Factor: 5.1). 01/2008; 169.
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ABSTRACT It is widely believed that synaptic plasticity may provide the neural mechanism that underlies certain kinds of learning and memory in the mammalian brain. The expression of long−term potentiation (LTP) in the hippocampus, an experimental model of synaptic plasticity, requires the GluR−A subunit of the AMPA subtype of glutamate receptor. Genetically modified mice lacking the GluR−A subunit show normal acquisition of the standard, fixed−location, hidden−platform watermaze task, a spatial reference memory task that requires the hippocampus. In contrast, these mice are dramatically impaired on hippocampus−dependent, spatial working memory tasks, in which the spatial response of the animal is dependent on information in short−term memory. Taken together, these results argue for two distinct and independent spatial information processing mechanisms: (i) a GluR−A−independent associative learning mechanism through which a particular spatial response is gradually or incrementally strengthened, and which presumably underlies the acquisition of the classic watermaze paradigm and (ii) a GluR−A−dependent, non−associative, short−term memory trace which determines performance on spatial working memory tasks. These results are discussed in terms of Wagner's SOP model (1981).

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