55
250 random strong inputs, Vth = [22 22 16 14], τ,θf = 4 ms
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0 100 200 300 400 500 600 700 800 900 1000
Time (ms)
1250 random weak inputs, Vth = [22 22 16 14], τ = 4 ms
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Time (ms)
Figure 2.16: Raster diagrams showing spikes computed for the nonlinear system (×,s) and the re-
duced system (o’s) for A) “strong” and B) “weak” input cases demonstrate that a variable-threshold,
multi-site IAF mechanism improves accuracy of spike generation. The same input patterns as used
for Figure 2.14 were applied to the forked neuron, but this time voltages were observed at the soma
and the midpoints of each branch. Threshold values are given in §2.7.2. In total, the “strong” and
“weak” input simulations had match scores of 56% and 65%, respectively, and mismatch scores of
15% and 13%, respectively.
it accurately tracks the quasi-active response at several, say p, distinct locations.
Proper investigation of this issue would address the questions of optimal placement
of p observers, placement and calibration of threshold mechanisms at each site, and
the trade of accuracy for speed as p is increased. We offer here only empirical evidence