3.0 2.5 2.0 1.5 1.0 0.5 0.4 0.3 0.2 0.1 0.0 3.0 2.5 2.0 1.5 1.0 10 8 6 4 2 0 Time (s) Facilitation index Time (s) Facilitation index A B F = 1.9 e −13 t

Figure 6.1i Facilitation Results. A. Student data for intervals of 20 ms to 10 s. Data have been fit with an exponential equation (rate constant 1/13, or 0.77). B. The first 500 ms of the data shown in A.

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