A system for detecting a neurological deterioration in a patient, the system constituted of: an analyzing module; and at least one input port arranged to receive a plurality of first samples of electroencephalographic (EEG) activity of the patient and a plurality of second samples of EEG activity of the patient and further arranged to output the received samples to the analyzing module, wherein the analyzing module is arranged to: compare a function of the received first EEG samples to a function of the received second EEG samples; determine the difference between the outcome of the comparison and a baseline value; and output a neurological deterioration signal responsive to the determined difference.