Creating Stable Memories

Department of Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Science (Impact Factor: 33.61). 02/2011; 331(6019):869-70. DOI: 10.1126/science.1202283
Source: PubMed


Social animals with a keen sense of smell, such as rats, can teach each other about the safety of new foods by a practice
called social transmission of food preference (STFP). In this olfactory learning paradigm, a rat that has just eaten can familiarize
another rat with the taste odor of a new food by allowing the naïve rat to sniff its breath. The naïve rat apparently infers
that the novel food is safe to eat because another rat has eaten it, and exhibits greatly diminished fear of the new food
at first exposure. On page 924 of this issue, Lesburguéres et al. (1) describe their discovery of two fascinating aspects of this form of long-term memory: Specific neurons or synapses in the
cerebral cortex are specifically “tagged” and thereby allocated to participate in a memory for a particular food odor, and
this process involves epigenetic molecular mechanisms.

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