An apparatus and method for automatically determining an individual's level of brain function is provided. EEG or MEG signals are collected amplified and digitized. The signals are then passed to a computer comprising a CPU, ROM and RAM, an input interface for collecting and filtering the scalp potential signals and an output interface for displaying the resulting information on a display device such as a printer or CRT. The computer determines the position of these signals in reference to the interpolated 3-D geometry of the subject's head. The dipolarity of a particular point is iteratively and empirically derived by comparing the values of these measured signals to a test signal and the error between the two is minimized. The procedure is repeated for the complete series of electrodes placed on the skull. The mean dipolarity of a subject is then determined for a given time frame. The subject's dipolarity is then compared against that of age matched subjects and scaled so that an estimation of the subjects degree of cognitive loss is determined.
Method and apparatus for measuring brain function