Sonority Effects and Learning Bias in Nasal Harmony

An important question in linguistics involves the nature of apparent substantive biases. Biases are often claimed to be universal based on typological evidence. This thesis tests for a substantive bias, the proposed universal implicational nasalized segment hierarchy in vowel-consonant nasal harmony, using an Artificial Grammar paradigm. In particular, I address whether a pattern that is predicted by the implicational hierarchy is in fact easier to learn than one that is not predicted or that is indeterminate with regard to predictions. I use a grammaticality judgment wug test paradigm to investigate whether it is easier to make a generalization when a more marked blocker (more sonorant segment) or target (less sonorant segment) is presented during an exposure phase and a less marked blocker (less sonorant segment) or target (more sonorant segment) in the test phase than vice versa. I call this the sonority hierarchy type prediction. In addition to testing the predictions on the basis of the hierarchy, I also test predictions based on natural classes. The natural class hypothesis predicts that a grammar is more learnable if a new segment (a segment introduced in the test phase but not present in the exposure phase) is of the same natural class as an old segment (a segment introduced in the exposure phase). The experiment was run with speakers of Min (Taiwan Southern Min), a language with no apparent evidence for sonority classes, using a method based on that of Wilson (2006). Experiments were carried out that allow both the sonority hierarchy type and the natural class hypotheses to be tested, taking individual differences (learner types) into account. The results show that both the sonority hierarchy and natural classes play a role, supporting the claim that it is easier to learn a grammar that exhibits a substantive bias than one that does not. In conclusion, this thesis suggests that the implicational nasalized segment hierarchy is testable and learnable in artificial grammar learning to some extent and natural classes are psychologically real and actively used by participants in nasal harmony.Ph.D