Social recognition memory requires protein synthesis after reactivation.
Recent evidence indicates that reactivation of consolidated memories returns them to a protein-synthesis-dependent state called reconsolidation. The hypothesis that memories reconsolidate has never been assessed in social memory. The authors tested whether sheep (Ovis aries) mothers' memory of their lambs undergoes reconsolidation upon reactivation. After 7 days of mother-young contact, ewes were separated from their lambs for 8 hr, after which the lambs were reintroduced to their mothers for a 10-min reactivation session. Before reactivation, mothers received a subcutaneous injection of either the protein-synthesis inhibitor cycloheximide (CY, 1 mg/kg) or vehicle. Mothers' lamb memory was tested 1 hr (short-term memory [STM]) or 16 hr (long-term memory [LTM]) after reactivation. Mothers treated with CY exhibited intact STM but deficient LTM. CY injection without reactivation or before presentation of an alien lamb induced no deficit in LTM. CY-induced LTM deficit was alleviated by (a) introducing a reminder just before the LTM test, (b) extending mother-young contact, and (c) preventing suckling by the familiar lamb during reactivation. Thus, reconsolidation can be shown to exist in social memory, and some of its boundary conditions are discussed.
Perrin
Gaëlle
G
UMR85 Laboratoire de Physiologie de la Reproduction et des Comportements, INRA, Nouzilly, France.
Ferreira
Guillaume
G
Meurisse
Maryse
M
Verdin
Sébastien
S
Mouly
Anne-Marie
AM
Lévy
Frédéric
F
D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D003513:Cycloheximide / Q000494:pharmacology; D005260:Female; D008425:Maternal Behavior / Q000187:drug effects / Q000502:physiology*; D014176:Protein Biosynthesis / Q000187:drug effects; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D021641:Recognition, Psychology / Q000187:drug effects / Q000502:physiology*; D012756:Sheep; D012919:Social Behavior; D013391:Sucking Behavior / Q000187:drug effects
D011500:Protein Synthesis Inhibitors; D003513:Cycloheximide