We have worked for a long time on the question which signal parameter the barn owls use to localize sounds. We found that the interaural time difference (ITD) is the main cue for localization in the horizontal plane or azimuth while the interaural level difference (ILD) is important for elevational sound localization (Fig. ITD/ILD: DFG). Further cues, like the monaural or binaural spectrum most likely also play a role, but their contribution has not been quantified so far. To make progress in this field, we have established virtual auditory worlds for owls (Figure Iris). By virtualle removing the ruff, we found that the ruff reduces ambiguities (Figure Hausmann. Recently we have started investigation on the influence of adaptation on sound localization and the influence of the interaural canal.
Most recent funding
DFG project WA 20-2
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