Minimal experience required for immediate-early gene induction in zebra finch neostriatum

We show that a single presentation of a zebra finch song, 2 a in duration, will induce an "immediate-early gene" response in the caudomedial neostriatum of zebra finches (Poephila guttata). Repetition of this stimulus 10 times is sufficient to induce a maximal increase in RNA and protein, detected 30 and 90 min later respectively. Thus very brief stimuli can set in motion a slow genomic process in the brain which takes hours to resolve. Immediate-early gene function is often considered in the context of a "feedback" model (i.e.: to consolidate memories of the inducing event). However, based on the long lag observed here between initiation and full expression of the molecular response, we suggest an alternative, ethologically based, "feed-forward" model in which exposure to a novel or significant context triggers an increase in the efficiency of memory capture processes for subsequent experiences, (C) 2000 Academic Press.