@phdthesis{Goetz2021,
  author    = {G{\"o}tz, Antonia},
  title     = {Patterns of perceptual reorganization in infancy},
  doi       = {10.25932/publishup-53618},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-536185},
  school      = {Universit{\"a}t Potsdam},
  pages     = {154},
  year      = {2021},
  abstract  = {Previous behavioral studies showed that perceptual changes in infancy can be observed in multiple patterns, namely decline (e.g., Mattock et al., 2008; Yeung et al., 2013), maintenance (e.g., Chen \& Kager, 2016) and U-shaped development (Liu \& Kager, 2014). This dissertation contributes further to the understanding of the developmental trajectory of phonological acquisition in infancy. The dissertation addresses the questions of how the perceptual sensitivity of lexical tones and vowels changes in infancy and how different experimental procedures contribute to our understanding. We used three experimental procedures to investigate German-learning infants' discrimination abilities. In Studies 1 and 3 (Chapters 5 and 7) we used behavioral methods (habituation and familiarization procedures) and in Study 2 (Chapter 6) we measured neural correlates. Study 1 showed a U-shaped developmental pattern: 6- and 18-month-olds discriminated a lexical tone contrast, but not the 9-month-olds. In addition, we found an effect of experimental procedure: infants discriminated the tone contrast at 6 months in a habituation but not in a familiarization procedure. In Study 2, we observed mismatch responses (MMR) to a non-native tone contrast and a native-like vowel in 6- and 9-month-olds. In 6-month-olds, both contrasts elicited positive MMRs. At 9 months, the vowel contrast elicited an adult-like negative MMR, while the tone contrast elicited a positive MMR. Study 3 demonstrated a change in perceptual sensitivity to a vowel contrast between 6 and 9 months. In contrast to the 6-month-old infants, the 9-month-old infants discriminated the tested vowel contrast asymmetrically. We suggest that the shifts in perceptual sensitivity between 6 and 9 months are functional rather than perceptual. In the case of lexical tone discrimination, infants may have already learned by 9 months of age that pitch is not relevant at the lexical level in German, since the infants in Study 1 showed no perceptual sensitivity to the contrast tested. Nevertheless, the brain responded to the contrast, especially since pitch differences are also part of the German intonation system (Gussenhoven, 2004). The role of the intonation system in pitch discrimination could be supported by the recovery of behavioral discrimination at 18 months of age, as well as behavioral and neural discrimination in German-speaking adults.},
  language  = {en}
}