Measurement of frequency selectivity of single neurons in the central auditory pathway

A large sample of threshold tuning curves of single units from various levels of the auditory pathway was used in order to examine the relationship between best frequency and a measure of sharpness of tuning. This measure is simply the tuning curve bandwidth at 20 dB above threshold on a square-root scale of frequency. The transformation was found to be largely independent of unit best frequency, suggesting that it is suitable for comparing sharpness of tuning between samples. No difference in sharpness of tuning was found between samples of units from nuclei in the lemniscal auditory pathway, although units from the anterior auditory field showed broader tuning than those in the lemniscal pathway.