Lexical representation and processing of word-initial morphological alternations: Scottish Gaelic mutation

When hearing speech, listeners begin recognizing words before reaching the end of the word. Therefore, early sounds impact spoken word recognition before sounds later in the word. In languages like English, most morphophonological alternations affect the ends of words, but in some languages, morphophonology can alter the early sounds of a word. Scottish Gaelic, an endangered language, has a pattern of ‘initial consonant mutation’ that changes initial consonants: P og ‘kiss’ begins with [p h ], but phog ‘kissed’ begins with [f]. This raises questions both of how listeners process words that might begin with a mutated consonant during spoken word recognition, and how listeners relate the mutated and unmutated forms to each other in the lexicon. We present three experiments to investigate these questions. A priming experiment shows that native speakers link the mutated and unmutated forms in the lexicon. A gating experiment shows that Gaelic listeners usually do not consider mutated forms as candidates during lexical recognition until there is enough evidence to force that interpretation. However, a phonetic identification experiment confirms that listeners can identify the mutated sounds correctly. Together, these experiments contribute to our understanding of how speakers represent and process a language with morphophonological alternations at word onset.