Volatile memristors consist of inherent natural exponential decay properties. We present a clear relationship between the variation of input signals and the time constant of the exponential decay properties. We propose a unique approach for controlling the time constants of the decay behavior through fine tuning of the gap width and amplitude. All memristors presented temporal behavior in the range of milliseconds with natural decay back to its original conductance state. We demonstrate the natural decay can be quantified and could be exploited for decoding input signals for reservoir computing, minimize device to device variation and benchmarking procedure.