Method and apparatus for determining brain activity including the nature of brain lesions by electroencephalography

A method of determining the electrical output of brain region in the head of a subject comprising applying electrodes from an EEG unit about the head of the subject, obtaining from the electrodes an electrical signal being first data representative of energy in the brain region in a primary frequency domain, determining from the electrodes an electrical signal being second data representative of energy in the primary frequency domain relative to the energy in a secondary frequency domain, relating the first data with the second data thereby obtaining a value representative of electrical output in the brain region, and obtaining a brain map of the representative value.

A method of determining the electrical output of a brain region in the head of a subject comprising applying electrodes from an EEG unit about the head of the subject obtaining from the electrodes an electrical signal being first data representative of energy in the brain region in a primary frequency domain, determining from the electrodes an electrical signal being second data representative of energy in the primary frequency domain relative to the energy in a secondary frequency domain, normalizing the first data, normalizing the second data, selecting a base value relative to the respective normalizations, determining departures of the first data and the second data from the respective selected base values, and relating the departures thereby to obtain a brain map representative of electrical output in the brain region.

A method of determining the electrical output of a brain region in the head of a subject comprising applying electrodes from an EEG unit about the head of the subject measuring from the electrodes an electrical signal representing an absolute power in the brain region in a primary frequency domain, determining from the electrodes an electrical signal representing a relative power in the primary frequency domain relative to the absolute power in a secondary frequency domain, normalizing the absolute power, normalizing the relative power, selecting a base value relative to the respective normalizations, determining departures of the absolute power and the relative power from the respective selected base values, and relating the departures thereby to obtain a cordance brain map representative of electrical output in the brain region.

Apparatus for determining the electrical output of a brain region in the head of a subject comprising electrodes from an EEG unit for location about the head of a human, means for obtaining from the electrodes first data representative of an energy in the brain region in a primary frequency domain, means for determining second data representative of energy in the primary frequency domain relative to the energy in a secondary frequency domain, means for relating the first data with the second data thereby obtaining a value representative of electrical output in the brain region, and means for presenting such value.