Barn owl auditory thresholds from Barn owls have ageless ears

Auditory thresholds from barn owls of different age group

Pictogram of the spectra of the stimuli used in the experiments.

<p>Black lines indicate the harmonics of the tone complex used as masker. The harmonics are multiples of the masker’s fundamental frequency F0. The lowest harmonic is not necessarily the fundamental frequency. The dotted line shows the frequency of the target component that had to be detected and was not part of the masker. Panels a to c show the frequency configurations of Experiments 1–3 in the harmonic condition. Panels d and e show the frequency configurations of the broad-band conditions with additional masker harmonics as used in Experiments 2 and 3.</p

Detection thresholds of the single target component in dB SPL as a function of mistuning in percent (bottom axis) or in Hz (top axis).

<p>Filled circles indicate thresholds obtained with a masker comprised of eight components (i.e.  = 8). Open circles show the thresholds obtained with the broadband conditions, with  = 32 in Experiment 2, and  = 40 in Experiment 3. Panel a: Thresholds obtained in Experiment 1, with resolved harmonics, with a fundamental frequency F0 = 160 Hz and a target frequency  = 800 Hz. Panel b: Thresholds obtained in Experiment 2, with unresolved harmonics, with a fundamental frequency F0 = 40 Hz and a target frequency  = 800 Hz. Panel c: Thresholds obtained in Experiment 3, with unresolved harmonics, with a fundamental frequency F0 = 160 Hz and a target frequency  = 4000 Hz. The error bars indicate the standard deviation across six normal-hearing subjects.</p