Perceptual similarity across sixteen languages

Learning perceptually similar, and thus hard to separate, languages may be different from learning perceptually dissimilar, easy to separate, languages. To test this hypothesis, a measure of perceptual language similarity is needed. The purpose of this thesis is to establish, describe and explore such a measure. In Study 1, implicit language similarity across 16 languages was tested. Adult participants were presented simultaneously with two recordings that were either of the same, or of two different languages. They responded whether they heard 1 or 2 languages. Responding "1" when two languages were presented is an indication that these languages sound similar. To understand why some language combinations were more likely to be perceived as a single language, parameters relating to properties of the listener population, language family, geographic closeness, and properties of language were investigated. In a multidimensional scaling analysis, geography and properties of the languages explained which language combinations were more likely to be perceived as a single language. To test which aspects of the results from Study 1 were task-dependent or task-independent, an explicit measure of language similarity was used in Study 2. Participants listened to each language separately and were asked to arrange languages that sound more similar closer together. The results from a multi-dimensional scaling analysis of the explicit judgments of language similarity could be explained by properties of the listener population, language family, geography, and properties of the languages. In comparison to Study 1, the explicit task may be more affected by listeners' meta-linguistic knowledge than by properties of the language. Finding out why some languages may be perceived as more similar can shed light on which properties of languages are salient to a naive listener. The implicit and explicit measures of language similarity described in this thesis can be used to test hypotheses about the role of language similarity in infants' and adults' language learning.%%%%L'apprentissage de langues qui sont similaires sur le plan perceptif, et consequemment plus difficile a dissocier, devrait etre different de l'apprentissage des langues qui, elles, sont differentes sur le plan perceptif, et plus facile a dissocier. Pour verifier cette hypothese, une mesure de la similarite perceptuelle des langues est necessaire. Le but de ce memoire est d'etablir, de decrire et d'explorer cette mesure. Dans l'Etude 1, la similarite implicite de 16 langues differentes a ete mesuree. Deux enregistrements, provenant ou non de la meme langue, ont ete presentes a des participants adultes. Les participaient devaient ensuite enoncer s'ils avaient entendu 1 ou 2 langues. Si les participaient repondaient «1», cela indiquait que les langues paraissaient semblables. Afin de mieux comprendre pourquoi certaines combinaisons de langues etaient plus souvent percues comme etant une seule langue, des parametres relatifs aux caracteristiques de la population du…