Simultaneous Recording and Sequential Recording of EcochG and ABR-MLR-SVR on the Logarithmic Time Scale

Abstract

An experimental study on recording of four kinds of auditory evoked responses, EcochG-ABR-MLR-SVR, on the sequential axis logarithmic time scale to elucidate the information of the auditory pathway. The subjects were young adults with normal hearing. EcochG was recorded at the promontory of the middle ear cavity-ipsilateral mastoid, and other three kinds of them were recorded at the vertex-ipsilateral ear. The sequential recording of EcochG and other three ere proceeded by the Micro-Vaxll minicomputer.
The stimulus sounds were click, tone pip and tone burst with 770msec intervals. Analysis time was 500msec. Pass-band of filter was 0.8-3000Hz.
The results were as follow:
1) The sequential recording of logarithmic time scale was able to display the components of auditory evoked responses without spoiling their characteristics.
2) In the case of obscure wave I of ABR, the sequential recording was possible to dicipher ABR correctly by using AP of EcochG instead of wave I of ABR.
3) This recording technique provides us the auditory electro-physiological aspects by the auditory pathway from the level of the inner ear to the auditory cortex.