Context-dependent categorical perception in a songbird.

Published

Journal Article

Some of the psychological abilities that underlie human speech are shared with other species. One hallmark of speech is that linguistic context affects both how speech sounds are categorized into phonemes, and how different versions of phonemes are produced. We here confirm earlier findings that swamp sparrows categorically perceive the notes that constitute their learned songs and then investigate how categorical boundaries differ according to context. We clustered notes according to their acoustic structure, and found statistical evidence for clustering into 10 population-wide note types. Examining how three related types were perceived, we found, in both discrimination and labeling tests, that an "intermediate" note type is categorized with a "short" type when it occurs at the beginning of a song syllable, but with a "long" type at the end of a syllable. In sum, three produced note-type clusters appear to be underlain by two perceived categories. Thus, in birdsong, as in human speech, categorical perception is context-dependent, and as is the case for human phonology, there is a complex relationship between underlying categorical representations and surface forms. Our results therefore suggest that complex phonology can evolve even in the absence of rich linguistic components, like syntax and semantics.

Full Text

Duke Authors

Cited Authors

  • Lachlan, RF; Nowicki, S

Published Date

  • February 2015

Published In

Volume / Issue

  • 112 / 6

Start / End Page

  • 1892 - 1897

PubMed ID

  • 25561538

Pubmed Central ID

  • 25561538

Electronic International Standard Serial Number (EISSN)

  • 1091-6490

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.1410844112

Language

  • eng