Electrode positioning system for an EEG electrode array

Overview

In order to analyze EEG recordings, it is important to know the exact locations of the electrodes relative to the person’s head. Many times, the EEG cap holding the electrodes is assumed. In addition to electrode positions, electrical coupling to the head is of importance to the proper analysis of the EEG recordings. It is of exceptional importance to exclude the electrical bridges due to improper spreading of the electrical coupling between the electrode and the head.

Existing solutions and their drawbacks

A possible system for estimating the positions of the electrodes relative to the head is the system utilizing 3D scanning: namely taking pictures of the person wearing the EEG electrodes from different angles and reconstructing the 3D model. However, during the process of taking the pictures from different angles, the person can move, preventing the reconstruction process. The process can be repeated several times until the subject is still enough to enable the proper scanning process. This method is frustrating and although it can be performed once as explained below, would exhaust the patient if needed to perform every two days (the EEG electrodes have to be re-wired every 2-3 days).

Another option is to use the system consisting of many synchronized cameras (about 15 cameras): this system while solving the problem of the person’s movement during the scanning, is cumbersome and too costly for home use.

Our solution

Electrode positioning system which is based on a single stereo camera pair. The stereo pair can be fixed to a display for ease of use. The subject will be provided the immediate feedback on the display what is recorded on both cameras. The 3D positioning of the electrodes will be estimated from two corresponding images of the electrodes in a process which is called triangulation. The recordings of both cameras have to be performed synchronously, using applications for surveillance.

Third inventor in the patent application is Evgeny Tzigin.

IP

Priority application filed