A Method for Determining Cortical Auditory Thresholds in Guinea Pigs

Abstract

A method for measuring evoked cortical potentials to acoustic stimuli through the intact dura mater of the guinea pig without computer averaging was studied. After exposure of the dura overlying the auditory cortex on the left side, thresholds to acoustic stimuli presented to the right ear were determined with a double tipped silver electrode by visual detection on an oscilloscope. The thresholds obtained are compared with other methods of determining audibility levels in the guinea pig. With relatively simple instrumentation, this method provides rapid and accurate determination of the audibility curve.