Sustained potential shifts and changes in acoustic evoked potentials after presentation of a non-acoustic priming stimulus to carp ( CYPRINUS CARPIO)

Abstract

1. 1. Recordings were made from the region of the midbrain tectum and torus semicircularis of sustained potential shifts (SPS) to a non-acoustic priming stimulus and the change in subsequent acoustic evoked potentials (AEPs) to-a train of six clicks after a long rest. 2. 2. In the absence of priming stimuli (a jet of saline or water to the flank) the AEP to the first click in a train had the highest amplitude; with these stimuli it became the most attenuated. 3. 3. The SPS to both non-acoustic stimuli was initially ( ca 4 sec) negative, then became positive for a similar time period. 4. 4. After saline jet the tectal and the torus AEP amplitude was significantly correlated with the torus SPS; after water jet, the tectal and the torus AEP durations were correlated with the SPS. 5. 5. Application of alumina gel to the posterior telencephalic border caused elevation of the torus AEP amplitude after some 5 hr.