Behavioral auditory function after transection of crossed olivo-cochlear bundle in the cat. IV. Study on pure-tone frequency discrimination.

The present report describes the frequency discrimination capability of the cat based on behavioral auditory measurements in conjunction with transection of the crossed olivo-cochlear bundle at the floor of the fourth ventricle. Using the repetitive method, cats were trained to respond to frequency differences from 8000 Hz. For the measurement of the frequency discrimination threshold, instead of using the descending method, the cats were trained to detect the absolute change in the frequency. With the given experimental paradigm, the average pre- and post-operative frequency discrimination thresholds were 114.3 Hz and 133.6 Hz in experimentals, and 128.3 Hz and 140.0 Hz in shams. Differences between the two groups were minimal and may simply represent functional biological variance.