The status of LTP as a mechanism of memory formation in the mammalian brain

Long-term potentiation (LTP) is a long-lasting increase in synaptic efficac y that many consider the best candidate currently available for a neural me chanism of memory formation and/or storage in the mammalian brain, In our t arget article, LTP: What's learning got to do with it?, we concluded that t here was insufficient data to warrant such a conclusion. In their commentar ies, Jeffery and Zhadin raise a number of important issues that we did not raise, both for and against the hypothesis. Although we agree with a number of these issues, we maintain that there remains insufficient evidence that LTP is a memory mechanism.