Primary phonological planning units in spoken word production are language-specific: Evidence from an ERP study

The influence of induced moods on aging of phonological encoding in spoken word production: an ERP study

This study investigated the influence of induced mood on the phonological encoding involved in Chinese spoken word production with a picture-word inference task while concurrently recorded electrophysiological signals. In the experiment, young and older participants watched videos for inducing positive, negative, or neutral mood, and then they were instructed to name target picture while ignoring phonologically related or unrelated distractor words. A phonological facilitation effect was observed in young adults but not in older adults, suggesting an age-related decline of phonological encoding. Both groups showed an inhibition effect in negative mood but not in positive mood, suggesting that speakers have different processing styles in different moods. ERP data revealed a phonological effect around the time window of 250-350 ms in both groups. Meanwhile, young adults showed a phonological effect around 350-450 ms in negative mood and positive mood which may reflect self-monitoring in speech production. We suggest that the former effect may reflect phonological encoding while the latter reflects self-monitoring of internal syllables or phonemes. Furthermore, induced moods influence the phonological effect in older and young adults differently. Behavioral and ERP results provide consistent evidence for the aging decline of phonological encoding in spoken word production.

The multiple phonological activation in Chinese spoken word production: An ERP study supporting cascaded model

A central issue in spoken word production concerns how activation is transmitted from semantic to phonological levels. The current study investigated the issue of seriality and cascadedness in Chinese spoken word production, via the combined semantic blocked paradigm (with homogeneous and heterogeneous blocks) and picture-word interference paradigm (with phonologically related, mediated and unrelated distractors). Naming latencies data showed a mediated effect via comparing mediated and unrelated distractors in homogeneous blocks, a phonological facilitation effect via comparing phonologically related and unrelated distractors in homogeneous and heterogeneous blocks, and a semantic interference effect via comparing homogeneous and heterogeneous blocks. Critically, cluster-based permutation test of ERP data demonstrated a mediated effect around 266-326ms and an overlapped pattern of semantic interference effect around 264-418ms and phonological facilitation effect around 210-310ms in homogeneous or around 236-316ms in heterogeneous blocks. These findings indicated that speakers activate phonological nodes of non-targets, and present a cascadedness pattern of the transmission from semantics to phonology in Chinese spoken production. The present study sheds new insight on the neural correlates of semantic and phonological effects, and provides behavioral and electrophysiological evidences for the cascaded model within a theoretical framework of lexical competition in speech production.

Parallel Processing of Semantics and Phonology in Spoken Production: Evidence from Blocked Cyclic Picture Naming and EEG

Spoken language production involves lexical-semantic access and phonological encoding. A theoretically important question concerns the relative time course of these two cognitive processes. The predominant view has been that semantic and phonological codes are accessed in successive stages. However, recent evidence seems difficult to reconcile with a sequential view but rather suggests that both types of codes are accessed in parallel. Here, we used ERPs combined with the "blocked cyclic naming paradigm" in which items overlapped either semantically or phonologically. Behaviorally, both semantic and phonological overlap caused interference relative to unrelated baseline conditions. Crucially, ERP data demonstrated that the semantic and phonological effects emerged at a similar latency (∼180 msec after picture onset) and within a similar time window (180-380 msec). These findings suggest that access to phonological information takes place at a relatively early stage during spoken planning, largely in parallel with semantic processing.

Behavioural evidence for segments as subordinate units in Chinese spoken word production: The form-preparation paradigm revisited

It is widely acknowledged that phonemic segments are primary phonological units, processed serially, in spoken word production of Germanic languages. However, evidence for a behavioural effect of single-segment overlap on Chinese spoken word production is lacking. The current study adopted the form-preparation paradigm to investigate the effects of segment predictability and segment repetition separately, which were mixed in previous studies. Native Mandarin Chinese speakers named pictures in the following conditions: predictable, unpredictable, and no segment repetition. Different positions in words (i.e., the onset and the rhyme) were examined at the same time. Results revealed a facilitation effect of onset predictability masked by an inhibition tendency of onset repetition, indicating Chinese speakers' ability to prepare the predictable onset. In contrast, rhyme predictability showed a non-significant effect. This pattern of results did not change no matter whether the conditions of unpredictable onset repetition and unpredictable rhyme repetition were mixed in the same context (Experiment 1) or extracted from different blocked contexts (Experiment 2). The finding provides essential support to the claim that phonemic segments are functionally engaged in Chinese spoken word production, and thus adds original evidence to the universal aspect of spoken word production.

Phonological network fluency identifies phonological restructuring through mental search

We investigated network principles underlying mental search through a novel phonological verbal fluency task. Post exclusion, 95 native-language Mandarin speakers produced as many items that differed by a single lexical tone as possible within one minute. Their verbal productions were assessed according to several novel graded fluency measures, and network science measures that accounted for the structure, cohesion and interconnectedness of lexical items. A multivariate regression analysis of our participants' language backgrounds included their mono- or multi-lingual status, English proficiency, and fluency in other Chinese languages/dialects. Higher English proficiency predicted lower error rates and greater interconnectedness, while higher fluency in other Chinese languages/dialects revealed lower successive similarity and lower network coherence. This inverse relationship between English and other Chinese languages/dialects provides evidence of the restructuring of the phonological mental lexicon.

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.

Transfer of sensorimotor learning reveals phoneme representations in preliterate children

Reading acquisition is strongly intertwined with phoneme awareness that relies on implicit phoneme representations. We asked whether phoneme representations emerge before literacy. We recruited two groups of children, 4 to 5-year-old preschoolers (N = 29) and 7 to 8-year-old schoolchildren (N = 24), whose phonological awareness was evaluated, and one adult control group (N = 17). We altered speakers' auditory feedback in real time to elicit persisting pronunciation changes, referred to as auditory-motor adaptation or learning. Assessing the transfer of learning at phoneme level enabled us to investigate the developmental time-course of phoneme representations. Significant transfer at phoneme level occurred in preschoolers, as well as schoolchildren and adults. In addition, we found a relationship between auditory-motor adaptation and phonological awareness in both groups of children. Overall, these results suggest that phoneme representations emerge before literacy acquisition, and that these sensorimotor representations may set the ground for phonological awareness.

Probing the Timing Recruitment of Broca's Area in Speech Production for Mandarin Chinese: A TMS Study

Although Broca’s area is widely recognized to play an important role in speech production, neuroscientists still debate on its timing recruitment across different languages. In order to investigate the precise time course of phonological encoding for Mandarin Chinese, we applied real triple-pulse transcranial magnetic stimulation (tpTMS) and sham tpTMS within Broca’s area at five different time windows respectively (150 ms, 225 ms, 300 ms, 400 ms and 500 ms) in picture naming task in Mandarin Chinese. To exclude unspecific TMS effects and to make sure that the effects observed in the study were really due to stimulation at Broca’s area, we also conducted a control experiment by a different group of subjects. Significant increases in reaction times (RTs) were observed when real TMS stimulation at Broca’s area was applied at 225 ms, 300 ms and 400 ms time windows with a peak at 225 ms, compared with sham TMS stimulation at other time windows. Our findings support the hypothesis that the phonological encoding in speech production for Chinese language may approximately start from 200 ms and end around 400 ms post target onset, a little earlier than that from 355 ms to 455 ms for Indo-European languages.