Temporal contiguity requirements for long-term associative potentiation/depression in the hippocampus

摘要: Abstract A previous study utilizing the powerful ipsilateral and weak crossed projection from entorhinal cortex to dentate gyrus in rat revealed that long-term potentiation is an associative process these systems. If alone receives potentiating stimulation consisting of 8 high-frequency trains 17.5 ms duration, it does not exhibit potentiation. However, can be induced if activated concurrently with converging system. The present designed determine degree synchrony required for interactions by varying timing order delivered two induction require perfectly synchronous activation crucial, however. Long-term activity system concurrent or follows projection. Indeed, there as much 20ms between 17.5ms systems, still induced. Activation precedes depresses responses evoked too long interval (200 ms, example), then depressed rather than potentiated. These results are discussed regard nature permissive lead us conclusion perfect temporal contiguity a requirement this prototypical elemental memory unit.