Brainstem responses in the quivering mutant mouse.

Abstract

The recessive quivering gene in mice produces general neurological abnormalities and deafness. Previous work indicated that cochlear responses (microphonics and compound action potentials) were normal in the quivering (qv/qv) mouse, but inferior colliculus evoked potentials had poor thresholds and abnormal latencies. The object of the present study was to record evoked potentials from the cochlear nucleus (CN) in quivering and control mice, and also to record surface responses. The CN evoked response in control mice consisted of two prominent positive peaks. The first peak appeared normal in the quivering CN, resulting in normal thresholds for detection of the response. However, the second peak in mutants was smaller and of longer latency. Surface responses in quivering showed a normal first wave followed by an abnormal wave pattern. It was concluded that the input from auditory nerve to CN in quivering is probably normal and that the central deficit in quivering is evident at the level of CN.