Modes of perceiving and processing information in birdsong (Agelaius phoeniceus, Molothrus ater, and Homo sapiens)

In a previous study I examined the abilities of red-winged blackbirds and brown-headed cowbirds trained with a go-right/go-left procedure to identify conspecific and alien song themes (Sinnott, 1980). Results showed that each bird species exhibited superior identification of conspecific final "trill" or "whistle" elements, relative to the alien species. The present study extends these results by examining human perception of these same song stimuli, by examining the effects of tutoring birds with alien final song elements, and by using latency analyses to investigate processing modes that are not apparent from analyses of percent-correct scores. Results suggest three different processing modes: First, humans attend primarily to the final song elements. Second, birds identifying alien songs attend primarily to the introductory elements and disregard information in the final elements. Third, birds identifying conspecific songs process both the initial and final elements, but their response latencies indicate that they direct their attention primarily to the initial elements and process the final elements without investing more time than do the alien birds that fixate on the initial elements. Conspecific special processing is discussed in relation to various psychophysical, ethological, and psycholinguistic frameworks. Human perception of birdsong is discussed in relation to backward recognition masking.