A monitoring or predicting system to detect the onset of a neurological episode, the system comprising :a neurological electrical input, the input being a digital representation of a neurologically derived signal; a converter to convert the digital signal into a digital data string; a pattern analyser to identify recurring patterns in the digital data string; and a monitor to measure a pattern-derived parameter, wherein an output from the monitor gives an indication of the onset or occasion of a neuronal activity in dependence on the pattern-derived parameter.