Figure 2. Mixed EPSP facilitation and synaptic hyperpolarization during RSS are greater in young-adult neurons compared to older cells.
A, Representative RSS at 7 Hz in a young-adult neuron. E1 (EPSP 1) and E2 (EPSP 2) describe the amplitude measures used to measure % FF of the EPSP. Horizontal bar indicates the time period during which FF was averaged for graphical representation in B. B, Quantitative group measures (means ± SEM) showing the effect of age on FF triggered at 3, 7 and 15 Hz. C, Quantitative data on SIHP measured across several frequencies. Synaptic hyperpolarization was measured during RSS at 3, 7 and 15, following a single action potential (AP), as well as following a burst of 4 action potentials stimulated synaptically at 50 Hz (inset; scale bar indicates 8 mV and 160 ms). Note that, unlike the AHP, the SIHP is smaller in aged compared to young-adult neurons. Values represent means ± SEM. Asterisk indicates p < 0.05.