HFS.

<p>Across all experimental conditions, rats in the HFS group exhibited HFS-induced potentiation of evoked responses considering both EPSP slope (<b>ABEF</b>) and PS amplitude (<b>CDGH</b>), whereas rats in the control group exhibited no change in the size of evoked responses after a matching number of test pulses. Above graphs: representative traces of evoked responses from rats in the HFS group before (solid line) and after (dashed line) HFS. * denotes HFS-induced potentiation of evoked responses above baseline, <i>p</i><.05.