Figure 1.

Spike parameters in the time domain: an amperometric spike is characterized by the Pre-Spike Foot (PSF), rising phase, spike and the falling phase. Here $I_{\text{max}}$ is the peak current, $t_{\text{rise}}$ is the rise time (from $25\%$ to $75\%$ of $I_{\text{max}}$), $t_{\frac{1}{2}}$ is the half peak width, $I_{\text{foot}}$ is the PSF current, $t_{\text{foot}}$ is the PSF duration, $Q_{\text{spike}}$ is the charge of the spike and $Q_{\text{foot}}$ is the charge of the PSF.