Piezoelectric film transducer for recording of oculography in electro-encephalogram-polygraphy.

Oculography is important during clinical electroencephalography (EEG). Routinely, silver-silver plate/cup electrodes have been used. However, the electrical activity of the anterior parts of the brain can be mixed with the effect of eye/eyelid movements. This can result in artifacts disturbing or making it impossible to differentiate the frontal activity of the brain from eye movement artifacts. Therefore, crystal piezoelectric materials have been used for oculography, but they are relatively fragile in practice. In this study we present a new type of piezoelectric transducer for the recording of oculography, a piezoelectric polyvinylidenefluoride (PVDF) film transducer. Our preliminary material consists of routine EEG recordings of 15 subjects performed by means of this method. All recordings were of good quality and corresponded well with the routine electro-oculography recordings.