European starlings (sturnus vulgaris) discriminate rhythms by rate, not temporal patterns

Abstract

Humans can perceive a regular psychological pulse in music known as the beat. The evolutionary origins and neural mechanisms underlying this ability are hypothetically linked to imitative vocal learning, a rare trait found only in some species of mammals and birds. Beat perception has been demonstrated in vocal learning parrots but not in songbirds. We trained European starlings (Sturnus vulgaris) on two sound discriminations to investigate their perception of the beat and temporal structure in rhythmic patterns. First, we trained birds on a two-choice discrimination between rhythmic patterns of tones that contain or lack a regular beat. Despite receiving extensive feedback, the starlings were unable to distinguish the first two patterns. Next, we probed the temporal cues that starlings use for discriminating rhythms in general. We trained birds to discriminate a baseline set of isochronous and triplet tone sequences. On occasional probe trials, we presented transformations of the baseline patterns. The starlings' responses to the probes suggest they relied on absolute temporal features to sort the sounds into “fast” and “slow” and otherwise ignored patterns that were present. Our results support that starlings attend to local features in rhythms and are less sensitive to the global temporal organization.

Rhythmic abilities in humans and non-human animals: a review and recommendations from a methodological perspective

“…While these studies explicitly targeted rhythmic pattern structure, performance could be based on memorizing only the first temporal interval [72]. Interestingly, jackdaws (Corvus monedula) were shown to not only distinguish two rhythmic patterns, but to maintain discrimination with tempo changes, suggesting more advanced abilities based on the pattern, or even the beat [73], in contrast with zebra finches, budgerigars [74] and starlings [75], who seem to have limited ability to use the beat to distinguish stimuli, but rather attend to absolute durations. Humans implicitly leverage rhythmic structure in isochronous sequences for the detection and discrimination of pitch differences [20,76], temporal shifts [77], sounds at hearing threshold [78] and silent gaps [79,80].…”

Within-species differences in vocal production learning in a songbird are associated with differences in flexible rhythm pattern perception

“…While these studies found context-dependent modulation of auditory responses, they did not test the ability of the animals to recognize a learned rhythm independently of tempo. Demonstrating this ability requires behavioral methods, and an important lesson from prior research is that training methods can strongly influence to what extent such abilities are revealed (e.g., compare [46] with [22] and [47] with [48]; see also [49]). More generally, the ability to relate neural activity to perception and behavior is critical for understanding the contributions of motor regions to detecting temporal periodicity and predicting the timing of upcoming events, two hallmarks of human rhythm processing that are central to music’s positive effect on a variety of neurological disorders.…”

“…While these studies found contextdependent modulation of auditory responses, they did not test the ability of the animals to recognize a learned rhythm independently of tempo. Demonstrating this ability requires behavioral methods, and an (1984) with Samuels et al (2021); see also Bouwer et al (2021)).…”

“…While these studies found context-dependent modulation of auditory responses, they did not test the ability of the animals to recognize a learned rhythm independently of tempo. Demonstrating this ability requires behavioral methods, and an important lesson from prior research is that training methods can strongly influence to what extent such abilities are revealed (e.g., compare van der Aa et al (2015) with Rouse et al (2021) and Hulse et al (1984) with Samuels et al (2021); see also Bouwer et al (2021)).…”

Rhythmic abilities in humans and non-human animals: A review and recommendations from a methodological perspective

“…While these studies explicitly targeted rhythmic pattern structure, performance could be based on memorizing only the first temporal interval [72]. Interestingly, jackdaws (Corvus monedula) were shown to not only distinguish two rhythmic patterns, but to maintain discrimination with tempo changes, suggesting more advanced abilities, based on the pattern, or even the beat [73], in contrast to zebra finches, budgerigars [74], and starlings [75], who seem to have limited ability to use the beat to distinguish stimuli, but rather attend to absolute durations.…”