EVIDENCE FOR A PERIPHERAL OLFACTORY MEMORY IN IMPRINTED SALMON

The remarkable homing ability of salmon relies on olfactory cues, but its cellular basis is unknown. To test the role of peripheral olfactor y receptors in odorant memory retention, we imprinted coho salmon (Onc orhynchus kisutch) to micromolar concentrations of phenyl ethyl alcoho l during parr-smolt transformation. The following year, we measured ph enyl ethyl alcohol responses in the peripheral receptor cells using pa tch clamp. Cells from imprinted fish showed increased sensitivity to p henyl ethyl alcohol compared either to cells from naive fish or to sen sitivity to another behaviorally important odorant (L-serine). Field e xperiments verified an increased behavioral preference far phenyl ethy l alcohol by imprinted salmon as adults. Thus, some component of the i mprinted olfactory homestream memory appears to be retained peripheral ly.