Interval and contour in serial pitch perception by a passerine bird, the European starling (Sturnus vulgaris).

Examined the capacity of starlings to perceive and process pitch information in serial acoustic patterns in 7 experiments. Exps I–III studied the discrimination of sequences of tones that rose or fell in pitch when the interval size between successive pitches changed relative to a standard baseline interval. The rising/falling discrimination maintained itself—the birds showed perceptual constancy—when intervals were halved, varied randomly in size, or changed to a continuous frequency sweep. Exps IV–VI examined discrimination performance when pitch contour (i.e., up and down pitch relation from tone to tone) was changed from the baseline patterns. Ss responded preferentially to early rising/falling pitch information on a pitch sequence; they ignored later relative pitch information even when it contradicted early information. However, they could delay pitch processing if initial tones lacked up or down pitch cues. Exp VII was an exploration of the birds' consistent predilection to use absolute frequency value, as opposed to relative pitch, as a discriminative cue in pitch pattern perception. Results suggest a comparison between the cognitive ability of humans and that of animals to process serial acoustic information. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory frequency generalization and a failure to find octave generalization in a songbird, the European starling (Sturnus vulgaris).

Examined frequency generalization in starlings (Sturnus vulgaris) that were trained to discriminate between individual frequencies. Starlings were tested for frequency generalization after training on 2- and 3-tone discriminations. There was no evidence for octave generalization, which is a hallmark of human absolute pitch perception. This suggests that avian absolute pitch perception must not be interpreted as identical with that in humans. A control experiment with 1-tone discriminations indicated that the presence of lit response keys affect the shape of the generalization gradients. Lit response keys are a common feature in avian auditory perception experiments, and this control experiment cautions that results may be affected by this seemingly minor procedural change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)