27 Journal of the Korean Society of Speech Sciences Vol.7 No.3 (2015.09.30) ksss.jams.or.kr ISSN 2005-8063, pp. 27~35 http://dx.doi.org/10.13064/KSSS.2015.7.3.027 Processing of allophonic variants from optional vs. obligatory phonological processes Han, Jeong-Im 1) ABSTRACT The purpose of this study is to examine the lexical representation of phonological variants derived from optional vs. obligatory phonological processes. Given that place assimilation is optionally processed, whereas nasal assimilation is obligatory in Korean, a long-term repetition priming experiment was conducted, using a shadowing task. Korean speakers shadowed words containing either assimilated or unassimilated consonants in three priming conditions and their shadow responses were evaluated. It was shown that in both place and nasal assimilations, shadowing latencies for unassimilated stimuli were longer than those for assimilated stimuli in the mismatched condition. These results suggest that even in the optional assimilation, assimilated variants were processed more easily and faster than the canonical variants. The present results argue against the frequency-based account of multiple lexical representation (Connine, 2004; Connine & Pinnow, 2006; Ranbom & Connine, 2007; Bürki, Ernestus, & Frauenfelder, 2010; Bürki, Alario, & Frauenfelder, 2011). Keywords: optionality, place vs. nasal assimilations, mental lexicon, long-term repetition priming, Korean 1. Introduction A key issue in spoken language recognition is how pronunciation variability is accommodated in the perception of speech signals and mapped to the lexical representation. One source of variability is phonological processes. For instance, the final consonant of the word right in English is realized as labial in the context of right berries, even though it is a coronal ([t]) when the word right appears alone (Gaskell & Marslen-Wilson, 1996, 1998; Gow, 2001, 2002, 2003; Lahiri & Marslen-Wilson, 1991; Mitterer & Blomert, 2003, among others). It may cause a mismatch between the speech signals (righ[p]) and a canonical lexical form (righ[t]). However, this variability caused by an 1) Konkuk University, jhan@konkuk.ac.kr This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2014S1A5A2A01011147). I am grateful to three anonymous reviewers for their insightful comments. Received: July 17, 2015 Revised: August 22, 2015 Accepted: August 25, 2015 assimilatory process may be tolerable for word recognition because retrieving a canonical form is possible. Two primary accounts have been proposed for how pronunciation variants are recognized. In one account, only an underling form, or a lexeme, is in the lexicon; and the other assumes multiple representations in the lexicon. In Levelt, Roelofs, & Meyer (1999) and Dell (1986), the coronal nasal is assumed to be in the lexicon, and the labial nasal is derived from the coronal nasal through an assimilation process. These models assume that even though there are several phonological variants, only one phonological representation is stored in the mental lexicon, and thus, the stored form is abstract and different from the actual pronunciation. These views have been challenged recently by some psycholinguistic studies (Patterson & Connine, 2001; LoCasto & Connine, 2002; Connine, 2004; Connine & Pinnow, 2006; Ranbom & Connine, 2007; Bürki, Ernestus, & Frauenfelder, 2010; Bürki, Alario, & Frauenfelder, 2011), where two lexemes have been proposed. For instance, Connine and her colleagues proposed multiple representations for phonological variants from a flapping process. The word-medial flapping is dominant in American English, such as the segment [t] (pretty [prɪɾi]). It was