Auditory duration discrimination in the parakeet (Melopsittacus undulatus).

Two parakeets were trained by a method of avoidance conditioning to respond to duration differences in successively occurring tone bursts. Difference limens for duration were obtained at six durations (20-160 ms) of a 2.86-kHz tone presented at a sensation level of 60 dB. Calculations of the Weber fractions at each duration showed threshold values which compare favorably to similar measures for man ranging between 0.10 and 0.20.