Fig. 1. LTP and non-stationary fluctuation analysis (NSFA) methodology.

a Schematic of a hippocampal brain slice for LTP experiments, and the positioning of recording (R1, R2) and stimulating (S1, S2) electrodes. The CA3 region was cut (dashed line) to reduce neuronal excitability. Representative field and whole cell responses (fEPSP and EPSC), simultaneously obtained from CA1 neurons. Five consecutive responses were averaged and the stimulus artifacts were blanked for clarity. b Induction protocols for weak, compressed and spaced TBS (wTBS, cTBS and sTBS) are graphically summarized. c Representative fEPSP recordings for LTP evoked by a single episode of TBS (weak TBS, blue arrow). d Simultaneously obtained EPSC recordings. e Upper traces are two sets of representative waveforms for individual sweeps (thin lines), superimposed with the scaled mean of 57 EPSCs (thick lines). Lower traces are the subtraction of the scaled mean from the representative individual EPSCs. f Corresponding current–variance relationship to estimate the unitary conductance (γ). Fluctuation of the individual decays was plotted against the mean EPSC. Solid line is a parabolic fit with 95% confidence intervals (shaded). Dotted line, the background average variance.