Studies of stereodynamic interaction of the EEG and auditory potentials of the limbic system and non-auditory frontal cortex.

These studies use 24 cats under non-anesthetic states. Electrodes are implanted, under appropriate anesthetic and stereotoxic procedures in non-auditory neocortical areas, nucleus accumbens, and certain nuclei of the amygdala complex. Auditory stimulation was done using the free field method with periodic tones at 2.0 KHz to 3.0 KHz at 80db. The auditory stimulation and recording was performed with hard wire and telemetry methods. The analog data is collected on FM tape and processed with minicomputer. Digital filtering, cross, coherence, phase, spectral and cycle time analyses are used on the analog data. In these studies, we have looked at the electroencephalogram (EEG) and the auditory evoked potentials (AEP) of cortical and subcortical regions using frequency and time domain methods. The analyses of the interaction of spatially distributed neuronal networks during EEG and AEP activity may give insights to topographical relations in the brain.