Cues for auditory stream segregation of birdsong in budgerigars and zebra finches: Effects of location, timing, amplitude, and frequency

Abstract

Deciphering the auditory scene is a problem faced by many organisms. However, when faced with numerous overlapping sounds from multiple locations, listeners are still able to attribute the individual sound objects to their individual sound-producing sources. Here, the characteristics of sounds important for integrating versus segregating in birds were determined. Budgerigars and zebra finches were trained using operant conditioning procedures on an identification task to peck one key when they heard a whole zebra finch song and to peck another when they heard a zebra finch song missing a middle syllable. Once the birds were trained to a criterion performance level on those stimuli, probe trials were introduced on a small proportion of trials. The probe songs contained modifications of the incomplete training song's missing syllable. When the bird responded as if the probe was a whole song, it suggests they streamed together the altered syllable and the rest of the song. When the bird responded as if the probe was a non-whole song, it suggests they segregated the altered probe from the rest of the song. Results show that some features, such as location and intensity, are more important for segregating than other features, such as timing and frequency.

Automatic counting of birds in a bird deterrence field trial

“…For this study, we used video stills from a field experiment conducted to replicate an aviary experiment in an open environment (Mahjoub et al, ). We used an acoustic bird deterrent that leverages the understanding of avian communication to design noise fields which make auditory stream segregation difficult for birds (Dent, Martin, Flaherty, & Neilans, ). This encourages the birds to relocate without hazing or harming the animal.…”

“…For this study, we used video stills from a field experiment conducted to replicate an aviary experiment in an open environment (Mahjoub et al, 2015). We used an acoustic bird deterrent that leverages the understanding of avian communication to design noise fields which make auditory stream segregation difficult for birds (Dent, Martin, Flaherty, & Neilans, 2016 the complexity for computer vision in this application. Since the camera placement was not optimized for computer vision, the birds only take up a small area of the frame, have a variety of orientations, and sometimes blend into the background.…”

Interaction of spatial and non‐spatial cues in auditory stream segregation in the European starling

“…Such separate processing of different cues by separate brain areas could provide for the general observation of additivity of the cues. Segregation of sequential sounds by different cues has previously also been investigated in the budgerigar and zebra finch (Dent et al, 2016). Varying a number of cues of a single syllable embedded in a model song of total of six syllables, they investigated the effect of localization cues, intensity, passband or syllable type (conspecific vs. heterospecific wrong syllable) in segregating this syllables from the rest of the song.…”

“…A spatial difference in the angle of sound incidence of as little as 8°in the human (Middlebrooks & Onsan, 2012) and 9.4°in the cat (Javier et al, 2016) can be sufficient to segregate acoustic signals from different sources. Zebra finches, a songbird, showed a segregated percept of song syllables when a probe syllable was spatially separated from the rest of the song resulting in angles of sound incidence by 90°or more (Dent et al, 2016). Such perceptual differences may relate to the spatial tuning of central auditory neurons (for review, see Grothe et al, 2010).…”

Selective auditory grouping by zebra finches: testing the iambic–trochaic law

“…Zebra finches, small songbirds, are a well-studied model species for auditory perception (e.g. Kriengwatana et al 2014; Dent et al 2016). Also, they are able to perceive stress in human speech and are sensitive to the stress pattern over a string of speech syllables (Spierings and ten Cate 2014), something that has also been demonstrated in Java sparrows (Naoi et al 2012) and budgerigars (Hoeschele and Fitch 2016).…”