Figure 1.

The output signal of DC-Stimulator PLUS, as a frequency distribution of the signal, the time plot of the signal, and a histogram. The signal was generated by a computer. In the stimulation mode “noise,” there is a random level of current generated for every sample (sampling rate 1280 samples/s). The random numbers are normally distributed; the probability density function follows a bell-shaped curve. The amplitude of 1 mA pp means that 99% of all generated amplitude values were between +500 μA and −500 μA.