Across the great divide: Proximate units at the lexical-phonological interface

Lexical Access in Preschool Mandarin-Speaking Children With Cochlear Implants

PURPOSE

Children with cochlear implants (CIs) have less experience accessing spoken language. Mandarin Chinese uses pitch information to contrast word meaning, and the signal that the CI devices provide is degraded. Thus, Mandarin-speaking children with CIs may face more challenges in the development of language skills. This study examines preschool Mandarin-speaking children's performance in lexical access. We hypothesized that children with CIs and their peers with normal hearing (NH) have comparable naming ability, but they process phonological or semantic information differently.

METHOD

Twenty children with CIs and 20 age-matched children with NH were tested. The cross-modal visual-auditory picture-word interference paradigm was applied. The distractor was either phonologically related (mao⁵⁵ cat -mao⁵¹ hat), semantically related (mao⁵⁵ cat -shu²¹⁴ mouse) or unrelated (mao⁵⁵ cat -zhi²¹⁴ paper) to the target, and it was aurally presented at four different points in time relative to the picture. Accuracy was compared between the two groups to tap into the children's naming abilities, and reaction time was analyzed to examine the effects of phonological and semantic information.

RESULTS

No group difference in accuracy was found. The phonologically related distractors led to significantly higher accuracy scores and shorter reaction times, whereas the semantically related distractors did not. Unlike the NH group, the CI group did not respond significantly faster or slower in phonologically related condition when the distractor and picture occurred simultaneously. Finally, the CI group made overall quicker responses than the NH group.

CONCLUSIONS

Children with CIs are as successful as children with NH in word retrieval and production, and the two groups both show phonological priming effect and lack semantic effect. However, children with CIs do not process phonological information as early as their NH peers, and they may be more tasks directed and hence make quicker responses.

Interference effects of phonological similarity in word production arise from competitive incremental learning

In the blocked cyclic naming task, native Mandarin speakers named pictures with disyllabic names in small sets and blocks, with the critical manipulation whether pictures within a block shared an atonal syllable or not. We found the expected facilitation when the overlapping portion of responses was in word-initial position, but we also replicated a recent observation that with 'inconsistent' overlap (shared syllables could be either in first or second word position), form overlap causes interference. Crucially, interference also occurred when phonologically unrelated filler trials or trials which required a nonlinguistic response were interleaved with the critical pictures. The same pattern was found with written responses and orthographic radical overlap. The results are best explained via "competitive incremental learning" between lexical and phonological representations. A computer simulation confirms that this principle generates interference, and that the result is unaffected by filler trials. We conclude that incremental learning constitutes a universal principle in the mapping from semantics to phonology in language production.

Orthographic properties of distractors do influence phonological Stroop effects: Evidence from Japanese Romaji distractors

In attempting to understand mental processes, it is important to use a task that appropriately reflects the underlying processes being investigated. Recently, Verdonschot and Kinoshita (Memory & Cognition, 46, 410-425, 2018) proposed that a variant of the Stroop task-the "phonological Stroop task"-might be a suitable tool for investigating speech production. The major advantage of this task is that the task is apparently not affected by the orthographic properties of the stimuli, unlike other, commonly used, tasks (e.g., associative-cuing and word-reading tasks). The viability of this proposal was examined in the present experiments by manipulating the script types of Japanese distractors. For Romaji distractors (e.g., "kushi"), color-naming responses were faster when the initial phoneme was shared between the color name and the distractor than when the initial phonemes were different, thereby showing a phoneme-based phonological Stroop effect (Experiment 1). In contrast, no such effect was observed when the same distractors were presented in Katakana (e.g., "くし"), replicating Verdonschot and Kinoshita's original results (Experiment 2). A phoneme-based effect was again found when the Katakana distractors used in Verdonschot and Kinoshita's original study were transcribed and presented in Romaji (Experiment 3). Because the observation of a phonemic effect directly depended on the orthographic properties of the distractor stimuli, we conclude that the phonological Stroop task is also susceptible to orthographic influences.

The proximate unit in Korean speech production: Phoneme or syllable?

We investigated the "proximate unit" in Korean, that is, the initial phonological unit selected in speech production by Korean speakers. Previous studies have shown mixed evidence indicating either a phoneme-sized or a syllable-sized unit. We conducted two experiments in which participants named pictures while ignoring superimposed non-words. In English, for this task, when the picture (e.g., dog) and distractor phonology (e.g., dark) initially overlap, typically the picture target is named faster. We used a range of conditions (in Korean) varying from onset overlap to syllabic overlap, and the results indicated an important role for the syllable, but not the phoneme. We suggest that the basic unit used in phonological encoding in Korean is different from Germanic languages such as English and Dutch and also from Japanese and possibly also Chinese. Models dealing with the architecture of language production can use these results when providing a framework suitable for all languages in the world, including Korean.

Syllables are Retrieved before Segments in the Spoken Production of Mandarin Chinese: An ERP Study

Languages may differ in terms of the functional units of word-form encoding used in spoken word production. It is widely accepted that segments are the primary units used in Indo-European languages. However, it is controversial what the functional units (syllables or segments) in Chinese spoken word production are. In the present study, Mandarin Chinese speakers named pictures while ignoring distractor words presented simultaneously, which shared atonal syllables, bodies or rhymes, or were unrelated with the name of the target pictures. Behavioral results showed that naming latencies in the 3 phonologically-related conditions were significantly shorter than those associated with the unrelated condition. EEG data indicated that the syllable-related condition modulated event-related potentials (ERPs) in a time window of 320–500 ms, the body-related condition modulated ERPs from 370–420 ms, while the rhyme-related condition modulated ERPs from 400–450 ms. The starting points for evident syllable, body, and rhyme priming effects were 322 ms, 368 ms, and 408 ms (by the Guthrie & Buchwald method) or 340 ms, 372 ms and 403 ms (by the jackknife procedure), respectively. Our findings provide a relative temporal course of syllable and segment encoding in Chinese spoken naming: Syllables are retrieved before segments, and constitute the primary processing units during the early stage of word-form encoding. Furthermore, segments and their order are retrieved incrementally from left to right when producing Chinese spoken words.

Tone slips in Cantonese: Evidence for early phonological encoding

This article examines speech errors in Cantonese with the aim of fleshing out a larger speech production architecture for encoding phonological tone. A corpus was created by extracting 2462 speech errors, including 668 tone errors, from audio recordings of natural conversations. The structure of these errors was then investigated in order to distinguish two contemporary approaches to tone in speech production. In the tonal frames account, tone is encoded like metrical stress, represented in abstract structural frames for a word. Because tone cannot be mis-selected in tonal frames, tone errors are expected to be rare and non-contextual, as observed with stress. An alternative is that tone is actively selected in phonological encoding like phonological segments. This approach predicts that tone errors will be relatively common and exhibit the contextual patterns observed with segments, like perseveration and anticipation. In our corpus, tone errors are the second most common type of error, and the majority of errors exhibit contextual patterns that parallel segmental errors. Building on prior research, a two-stage model of phonological tone encoding is proposed, following the patterns seen in tone errors: Tone is phonologically selected concurrently with segments, but then sequentially assigned after segments to a syllable.

Mora or more? The phonological unit of Japanese word production in the Stroop color naming task

In English, Dutch, and other European languages, it is well established that the fundamental phonological unit in word production is the phoneme; in contrast, recent studies have shown that in Chinese it is the (atonal) syllable and in Japanese the mora. The present study investigated whether this cross-language variation in the size of the unit of word production is due to the type of script used in the language (i.e., alphabetic, morphosyllabic, or moraic). Capitalizing on the multiscriptal nature of Japanese, and using the Stroop color naming task, we show that the overlap in the initial mora between the color name and the written distractor facilitates color naming independent of script type. These results confirm the mora as the phonological unit of word production in Japanese, and establish the Stroop color naming task as a useful task for investigating the fundamental (or "proximate") phonological unit used in speech production.

The influence of orthographic experience on the development of phonological preparation in spoken word production

Three sets of experiments using the picture naming tasks with the form preparation paradigm investigated the influence of orthographic experience on the development of phonological preparation unit in spoken word production in native Mandarin-speaking children. Participants included kindergarten children who have not received formal literacy instruction, Grade 1 children who are comparatively more exposed to the alphabetic pinyin system and have very limited Chinese character knowledge, Grades 2 and 4 children who have better character knowledge and more exposure to characters, and skilled adult readers who have the most advanced character knowledge and most exposure to characters. Only Grade 1 children showed the form preparation effect in the same initial consonant condition (i.e., when a list of target words shared the initial consonant). Both Grade 4 children and adults showed the preparation effect when the initial syllable (but not tone) among target words was shared. Kindergartners and Grade 2 children only showed the preparation effect when the initial syllable including tonal information was shared. These developmental changes in phonological preparation could be interpreted as a joint function of the modification of phonological representation and attentional shift. Extensive pinyin experience encourages speakers to attend to and select onset phoneme in phonological preparation, whereas extensive character experience encourages speakers to prepare spoken words in syllables.

The Emergence of a Phoneme-Sized Unit in L2 Speech Production: Evidence from Japanese-English Bilinguals

Recent research has revealed that the way phonology is constructed during word production differs across languages. Dutch and English native speakers are suggested to incrementally insert phonemes into a metrical frame, whereas Mandarin Chinese speakers use syllables and Japanese speakers use a unit called the mora (often a CV cluster such as "ka" or "ki"). The present study is concerned with the question how bilinguals construct phonology in their L2 when the phonological unit size differs from the unit in their L1. Japanese-English bilinguals of varying proficiency read aloud English words preceded by masked primes that overlapped in just the onset (e.g., bark-BENCH) or the onset plus vowel corresponding to the mora-sized unit (e.g., bell-BENCH). Low-proficient Japanese-English bilinguals showed CV priming but did not show onset priming, indicating that they use their L1 phonological unit when reading L2 English words. In contrast, high-proficient Japanese-English bilinguals showed significant onset priming. The size of the onset priming effect was correlated with the length of time spent in English-speaking countries, which suggests that extensive exposure to L2 phonology may play a key role in the emergence of a language-specific phonological unit in L2 word production.

The Contributions of Segmental and Suprasegmental Information in Reading Chinese Characters Aloud

The Chinese writing system provides an excellent case for testing the contribution of segmental and suprasegmental information in reading words aloud within the same language. In logographic Chinese characters, neither segmental nor tonal information is explicitly represented, whereas in Pinyin, an alphabetic transcription of the character, both are explicitly represented. Two primed naming experiments were conducted in which the targets were always written characters. When logographic characters served as the primes (Experiment 1), syllable segmental and tonal information appeared to be represented and encoded as an integral unit which in turn facilitated target character naming. When Pinyin served as the primes (Experiment 2), the explicit phonetic representation facilitated encoding of both segmental and suprasegmental information, but with later access to suprasegmental information. In addition, Chinese speakers were faster to name characters than Pinyin in a simple naming task (Experiment 3), suggesting that Pinyin may be read via a phonological assembly route, whereas characters may be read via a lexical route. Taken together, our findings point to the need to consider the contributions of both segmental and suprasegmental information and the time course in the well-established models for reading aloud, as well as the cognitive mechanisms underlying the reading aloud of logographic characters versus alphabetic Pinyin script.