Hearing Words Without Structure: Subliminal Speech Priming and the Organization of the Moroccan Arabic Lexicon

This dissertation investigates the mental representation of the root in the Moroccan dialect of spoken Arabic. While morphemes like roots have traditionally been defined as the smallest unit of sound-meaning correspondence, this definition has been long known to be problematic (Hockett, 1954). Other theories suggest that roots may be abstract units devoid of phonological or semantic content (Pfau, 2009; Harley, 2012) or that words are the basic unit of the mental lexicon (Aronoff, 1994, 2007; Blevins, 2006). The root of Moroccan words is examined with auditory priming experiments, using auditory lexical decision tasks, including the subliminal speech priming technique (Kouider and Dupoux, 2005). Chapter 2 shows that the subliminal speech priming technique should be modified with primes compressed uniformly to 240ms for Moroccan Arabic (the compression rate varies to achieve the uniform 240ms prime duration).Chapters 3 and 4 apply supraliminal and subliminal speech priming technique to Moroccan Arabic. The priming effect of words that share a root are found to be robust and distinct from words which simply share semantic or phonological content. Furthermore, roots which are instantiated as novel coinages produce priming effects, which further suggests that the root is a structural unit. Each related word in a morphological family, however, does not prime all of its relatives, contradicting the idea of a root as a structural unit. These subliminal effects also differ from supraliminal effects, where overlap in phonological form between the prime and target results in facilitation when identifying the target. The results of these experiments suggest that the word is the basic unit of speech perception, rather than the root. The root is is not an mental unit but a property of words or relationship among a morphological family. Competition from phonological neighbors is a late effect, since shared phonology facilitates only with the supraliminal technique but not the subliminal technique. Finally, realizational theories of morphology are supported, since take the word as the basic unit of the lexicon. While the root may not have phonological content per se, root phonology is important for deriving morphological families. Chapter 4 uses weak roots (which do not consistently show three root consonants in each derived form) to show that semi-vowels are encoded as root consonants.Release after 05-Aug-201