A method and apparatus for neurological assessment are provided. More specifically, the present invention relates to assessing central nervous system (CNS) function or the change in CNS function. The system (10) includes a monitoring device (20) for monitoring the brain activity of a patient (5) in response to one or more stimuli provided to the patient. Data from the monitoring device (20) is analyzed to determine a measure of CNS condition for the patient. The patient data can be compared with similar data obtained for the patient at a different time to aid a medical professional in the diagnosis or treatment of a neurological or neurodegenerative condition.