UBC Theses and Dissertations
Discrimination learning of nasalized and non-nasalized vowels by five-, six-, and seven-year-old children. Wyman, Virginia Jean
Fifteen predominantly English-speaking, and nine predominantly French-speaking kindergarten and grade one children served as subjects in an experiment designed to investigate discrimination learning of distinctive features. Stimuli were presented aurally and consisted of (a)meaningful non-linguistic sounds, (b)four Non-Nasalized Vowels, (c)Nasalized equivalents of the Non-Nasalized Vowels. Subjects were required to press one of four response buttons on each trial. Feedback was provided. Testing continued until all subjects had achieved asymptote across all Tasks. Mean probability of a correct response by session was compared for (a) linguistic versus non-linguistic Tasks, (b)Non-Nasalized versus Nasalized Vowels, and (c)the distinctive features characterizing the vowels. Confusion matrices were obtained for inter-vowel confusions. Results shewed that: (a)linguistic stimuli were not as well learned as non-linguistic stimuli, (b)Nasalized Vowels were learned significantly less well than their Non-Nasalized equivalents, and (c)only the distinctive feature ±nasal appeared to correlate with discrimination learning scores. The other features,±round and ±back , did not appear to operate independently in vowel perception. No evidence was obtained to support the hypothesis that one feature is more easily learned than other features within a discrimination learning task, or that a hierarchy governing the perception of distinctive features exists. The youngest children, however, were observed to perform linguistic tasks significantly less well than the older children. The mains effect for linguistic background of subjects was not significant, although significant interactions between this variable and particular tasks were obtained. Vowels best learned by the children were found to be those that elicited the largest number of verbally mediated responses; these were usually onomatopoeic in nature. Analysis of the discrimination learning results was found to be more amenable to interpretation in terms of traditional parameters of the vocal tract than in terms of distinctive features. No one theoretical framework, however, served consistently to explain the perceptual results obtained.