Cognition & plasticity
As detailed in Thompson et al. (1992) and Moyer et al. (1992) [see items 20. and 21., at http://www.utdallas.edu/~tres/neuro_pubs.html), aging hippocampal neurons are less excitable than young neurons, due to increases in the afterhyperpolarization following neuronal firing, mediated by Ca2+-dependent K+ conductances. This increase in the AHP opposes the reduced AHP normally present after learning.