Spoken Word Production Research Articles

Aging Effects on Phonological and Semantic Priming in the Tip-of-the-Tongue: Evidence From a Two-Step Approach.

The mechanism underlying the age difference in spoken word production remains controversial. We used a two-step approach proposed by Gollan and Brown (2006) to investigate the semantic and phonological retrieval deficits when tip-of-the-tongue occurs in young and older adults. Importantly, we controlled the inhibition ability in both older and young groups. In experiment 1 with a people pictures naming task, older adults produced more TOTs than young adults, and they suffered from phonological retrieval deficit rather than semantic retrieval deficit in speaking. In experiment 2 with a priming paradigm, participants were presented semantically related or phonologically related names before target pictures, which formed semantic or phonological priming conditions for lexical access. Compared with young adults, older adults showed a greater effect of phonological priming on decreasing TOTs occurrence. For semantic retrieval deficit, older adults exhibited a smaller phonological facilitation effect and a larger semantic interference effect than young adults. For phonological retrieval deficit, older adults presented a larger phonological facilitation effect in the first-name related priming condition than the first-syllable related priming condition, whereas young adults showed similar facilitation effects between the two phonological priming conditions. Our findings provide consistent evidence for the transmission deficit hypothesis, and highlight that aging affects bidirectional connections between semantic and phonological nodes in speech production.

The roles of syllables and phonemes during phonological encoding in Chinese spoken word production: A topographic ERP study

Languages may differ in their proximate units of phonological encoding in spoken word production. The roles of syllables and phonemes when Mandarin Chinese speakers prepare spoken words remain controversial. In the present study, native Chinese speakers named disyllabic pictures that were preceded by briefly presented and masked prime words while electroencephalogram signals were recorded. Prime words were syllabically or phonemically related to the first syllable of targets or were unrelated. Variables of prime type (syllable overlap or phoneme overlap) and relatedness (related or unrelated) were manipulated in the experiment. Behavioral results demonstrated a critical interaction between prime type and relatedness, with a facilitation effect relative to unrelated primes appearing only in the syllable overlap condition. Spatio-temporal segmentation analysis indicated that syllable relatedness shortened the duration of Map 6 (around 285–410 ms), whose time window is associated with the phonological encoding stage. Comparatively, phoneme relatedness shortened the duration of Map 7 (around 410–480 ms) in a later time window. Onset latency analysis suggested an earlier onset for the syllable effect (284 ms) and a chronologically later onset for the phoneme effect (396 ms). Traditional waveform analysis revealed that the syllable overlap condition exerted significant effects on event-related potentials in the time window of 280–440 ms, whereas the phoneme overlap condition produced a weak effect in the time window of 400–440 ms in a few electrodes. Taken together, these findings substantiate the primacy of abstract syllables in producing Mandarin spoken words and provide initial topographic evidence that Mandarin speakers mentally represent subordinate phonemes at a later stage of word-form encoding.

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.

Syntactic cueing of spoken naming in jargon aphasia

ABSTRACT Background: Debate surrounds the relationships between the systems involved in spoken word production, the activation governing production, and the role of syntax in production. Jargon aphasia provides an opportunity to investigate the relationship between syntax and phonology as it often involves retained syntax, alongside phonological deficits shown through neologistic output. Models of spoken word production differ in terms of their accounts of the processing relationships between these two levels of representation, and the degree to which syntax is activated and affects phonology. Aims: We aimed to complete a single case study investigation of the impact of syntactic cues on spoken word production, and to compare data from this implicit task with data from an explicit syntax judgement task. The investigation aims to shed light on different theories of spoken word production, provide new evidence concerning the nature of the deficit in jargon aphasia, and identify potential intervention methods. Methods & Procedures: The participant DP presented with transcortical sensory aphasia, with fluent neologistic output, a comprehension deficit, anomia, and preserved repetition. The investigations into DP’s noun syntax processing included syntactic cueing of naming, and a syntactic judgement task. The cueing task compared cued and uncued naming, where cues provided syntactic information relevant to count or mass noun targets. The judgement task investigated DP’s knowledge of potential determiner plus noun combinations. Outcomes and results: Syntactic cues led to increased overall naming accuracy, increased numbers of nouns, more phonologically related errors, and fewer unrelated word errors. The cues had no effect on the proportion of lexical versus non-lexical responses, nor on rates of semantic errors. In contrast to the positive impact of cues, DP showed limited knowledge of the meanings of determiners via the explicit judgement task. Conclusions: The evidence supports a spoken word production theory that has feedforward only activation from the syntactic to the semantic level, but allows interaction between syntactic and phonological representations. This account explains the lack of semantic errors, and the increase in phonologically related errors in the cued condition. DP’s difficulties completing the explicit judgement task provide more evidence of the need for online tasks which address language processing directly. New evidence of positive effects of syntactic cues on word retrieval informs future interventions for speakers with jargon aphasia.

Neural Mechanisms for Monitoring and Halting of Spoken Word Production.

During conversation, speakers monitor their own and others' output so they can alter their production adaptively, including halting it if needed. We investigated the neural mechanisms of monitoring and halting in spoken word production by employing a modified stop signal task during fMRI. Healthy participants named target pictures and withheld their naming response when presented with infrequent auditory words as stop signals. We also investigated whether the speech comprehension system monitors inner (i.e., prearticulatory) speech via the output of phonological word form encoding as proposed by the perceptual loop theory [Levelt, W. J. M. Speaking: From intention to articulation. Cambridge, MA: MIT Press, 1989] by presenting stop signals phonologically similar to the target picture name (e.g., cabbage-CAMEL). The contrast of successful halting versus naming revealed extensive BOLD signal responses in bilateral inferior frontal gyrus, preSMA, and superior temporal gyrus. Successful versus unsuccessful halting of speech was associated with increased BOLD signal bilaterally in the posterior middle temporal, frontal, and parietal lobes and decreases bilaterally in the posterior and left anterior superior temporal gyrus and right inferior frontal gyrus. These results show, for the first time, the neural mechanisms engaged during both monitoring and interrupting speech production. However, we failed to observe any differential effects of phonological similarity in either the behavioral or neural data, indicating monitoring of inner versus external speech might involve different mechanisms.

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.

Effects of semantic neighbourhood density on spoken word production.

When producing words, it is generally agreed that semantically related words are activated along with the target. However, relatively little is known about the extent to which the number of such semantically related words affects the production of spoken words. The research presented here explores, in detail, the influence of semantic neighbourhood density-the number of words of similar meaning in the lexicon-on picture naming performance in both unimpaired speakers and a large group of individuals with aphasia. In Experiment 1, six different semantic neighbourhood density measures were compared using principal component analysis. Four different semantic neighbourhood density components were identified: feature-based, context-based, association-based, and distant. In Experiment 2, these new measures were used as predictors in an analysis of picture naming data from unimpaired English speakers: no significant effects of semantic neighbourhood factors were observed on either latency or accuracy. Finally, Experiment 3 reports an analysis of picture naming responses of a large group of individuals with aphasia (n = 193), examining the influence of the semantic neighbourhood density measures. Effects of the feature-based semantic neighbourhood measure on accuracy varied across participants with no overall main effect. This same measure increased the probability of a coordinate error compared with a correct response but also compared with an omission. Results are best accommodated by theories of word production that incorporate mechanisms by which semantically related concepts can both facilitate and inhibit target production.

Prediction of orthographic information during listening comprehension: A printed-word visual world study.

Two visual world eye-tracking experiments examined the role of orthographic information in the visual context in pre-activation of orthographic and phonological information using Japanese. Participants heard sentences that contained a predictable target word and viewed a display showing four words in a logogram, kanji (Experiment 1) or in a phonogram, hiragana (Experiment 2). The four words included either the target word (e.g., /sakana/; fish), an orthographic competitor (e.g., /tuno/; horn), a phonological competitor (e.g., /sakura/; cherry blossom), or an unrelated word (e.g., /hon/; book), together with three distractor words. The orthographic competitor was orthographically or phonologically dissimilar to the target in hiragana. In Experiment 1, target and orthographic competitor words attracted more fixations than unrelated words before the target word was mentioned, suggesting that participants pre-activated orthographic form of the target word. In Experiment 2, target and phonological competitor words attracted more predictive fixations than unrelated words, but orthographic competitor words did not, suggesting a critical role of the visual context. This pre-activation pattern does not fit with the pattern of lexical activation in auditory word recognition, where orthography and phonology interact. However, it is compatible with the pattern of lexical activation in spoken word production, where orthographic information is not automatically activated, in line with production-based prediction accounts.

The role of orthography in second-language spoken word production: Evidence from Tibetan Chinese bilinguals.

Evidence suggests that spoken language production involves involuntary access to orthographic representations, both in languages with alphabetic and non-alphabetic scripts. An unexplored question is whether the role of orthography varies as a function of the language being native or non-native to the individual. Native (L1) and non-native (L2) languages differ in important aspects, that is, lexical representations in L2 might be less well established, but acquired at least partly via reading, and these unique features of non-native languages may contribute to a fundamental difference in how spelling and sound interact in production. We investigated an orthographic impact on spoken production with Tibetan Chinese bilinguals who named coloured line drawings of objects with Chinese adjective-noun phrases. Colour and object names were orthographically related or unrelated. Even though none of the participants were aware of the orthographic manipulation, orthographic overlap generated a facilitatory effect. In conjunction with earlier findings from native speakers on the identical task, we conclude that orthographic information is activated in spoken word production regardless of whether the response language is native or non-native.

The neurobiology of taboo language processing: fMRI evidence during spoken word production

Every language has words deemed to be socially inappropriate or ‘taboo’ to utter. Taboo word production appears prominently in language disorders following brain injury. Yet, we know little about the cognitive and neural mechanisms involved in processing taboo compared to neutral language. In the present study, we introduced taboo distractor words in the picture word interference paradigm during functional magnetic resonance imaging to investigate how these words influence spoken word production. Taboo distractor words significantly slowed picture-naming latencies compared to neutral words. This interference effect was associated with increased blood oxygen level dependent signal across a distributed thalamo-cortical network including bilateral anterior cingulate cortex and left inferior frontal gyrus, left posterior middle temporal gyrus and right thalamus. We interpret our findings as being consistent with an account integrating both domain-general attention-capture/distractor blocking and language-specific mechanisms in processing taboo words during spoken word production.

A computationally implemented mechanistic account of post-stroke aphasia recovery

A computationally implemented mechanistic account of post-stroke aphasia recovery

Electrophysiological evidence for the time course of syllabic and sub-syllabic encoding in Cantonese spoken word production

ABSTRACTThis study was conducted to investigate the time course of syllabic and sub-syllabic encoding in Cantonese Chinese spoken word production using the picture-word interference task with concurrent recording of event-related brain potential (ERP) signals. Cantonese-speaking participants were asked to name aloud individually presented pictures and ignore an accompanying auditory word distractor. Participants’ naming responses were faster, relative to an unrelated control, when the target (e.g. /gu2/, meaning “drum”) was presented together with a distractor sharing the same atonal syllable (e.g. /gu3/), or syllable body (e.g. /gung1/). More importantly, the ERP effects associated with syllable-related priming appeared earlier than those associated with body-related priming. The earlier effects of syllable-related priming relative to body-related priming indicate that syllable retrieval precedes sub-syllabic specification in Cantonese phonological encoding, consistent with the proximate unit hypothesis that the nature of the proximate phonological unit (i.e. the first selectable phonological unit following lexical access) is language dependent.

Syllable retrieval precedes sub-syllabic encoding in Cantonese spoken word production.

Two experiments were conducted to investigate the time course of syllabic and sub-syllabic processing in Cantonese spoken word production by using the picture-word interference task. Cantonese-speaking participants were asked to name individually presented pictures aloud and ignore an auditory word distractor. The targets and distractors were either phonologically related (i.e., sharing two identical word-initial phonemes) or unrelated. In Experiment 1, the target syllables were all consonant-vowel (CV)-structured. The phonological distractor was either a CV syllable (i.e., Full Syllable Overlap) or a CVC (consonant-vowel-consonant) syllable (i.e., Sub-syllable Overlap). Relative to the unrelated control, Full Syllable Overlap distractors facilitated naming in all stimuli onset asynchronies (SOAs) (-175, 0, or +175 ms) whereas Sub-syllable Overlap distractors exhibited facilitation only at 0-ms and +175-ms SOAs. Experiment 2 adopted a similar design to examine the possible influence of syllabic structure similarity on the results of Experiment 1. The target syllables were all CVC-structured. The phonological distractor was either a CVC (i.e., Syllable-structure Consistent) or CV (i.e., Syllable-structure Inconsistent) syllable. Comparable priming was observed between the two distractor conditions across the three SOAs. These results indicated that an earlier priming effect was observed with full syllable overlap than sub-syllabic overlap when the degree of segmental overlap was held constant (Experiment 1). The earlier syllable priming observed in Experiment 1 could not be attributed to the effect of syllabic-structure (Experiment 2), thereby suggesting that the syllable unit is important in Cantonese and is retrieved earlier than sub-syllabic components during phonological encoding.

Plural dominance and the production of determiner-noun phrases in French.

In two experiments, we examined the functional locus of plural dominance in the French spoken word production system, where singulars and plurals share the same phonological word form. The materials included singular-dominant (singular more frequent than plural) and plural-dominant nouns (plural more frequent than singular). In Experiment 1, participants were instructed to produce determiner-noun phrases in response to singular and plural depictions of objects. In contrast to the dominance-by-number interaction that is typically observed in English, Dutch and German, the French picture-naming data revealed a main effect of number, but no effect of plural dominance. When participants were instructed to produce determiner-noun phrases in a reading aloud task (Experiment 2), where number is orthographically marked, a number-by-dominance interaction emerged. Our data suggest that plural dominance is encoded at the word form level within the context of recent theories of spoken word production.

How modality-specific is morphology?

ABSTRACTWriting has long been considered to be dependent on speaking. However, modality-specific dissociations between written and spoken word production imply that word production is supported by distinct neural mechanisms in writing, which can be impaired or spared regardless of the intactness of spoken word production. Rapp et al. (2015). Modality and morphology: What we write may not be what we say. Psychological Science, 26, 892–902 documented a double dissociation where problems with regular inflections were selectively restricted to writing or speaking. We report on two English-speaking aphasic individuals who exhibit this same modality-specific dissociation of inflectional processing, replicating the original findings. We expand on Rapp et al.’s study by examining whether the dissociations observed with regular inflections extend to other morphological forms, such as derivation and irregular inflection. Results showed that the dissociation holds for derivation; however, both participants were impaired with irregular inflections in both output modalities. Implications of these findings for morphological processing and the independence of the orthographic system are discussed.

Spoken-word production in Korean: A non-word masked priming and phonological Stroop task investigation.

Speech production studies have shown that phonological unit initially used to fill the metrical frame during phonological encoding is language specific, that is, a phoneme for English and Dutch, an atonal syllable for Mandarin Chinese, and a mora for Japanese. However, only a few studies chronometrically investigated speech production in Korean, and they obtained mixed results. Korean is particularly interesting as there might be both phonemic and syllabic influences during phonological encoding. The purpose of this study is to further examine the initial phonological preparation unit in Korean, employing a masked priming task (Experiment 1) and a phonological Stroop task (Experiment 2). The results showed that significant onset (and onset-plus, that is, consonant-vowel [CV]) effects were found in both experiments, but there was no compelling evidence for a prominent role for the syllable. When the prime words were presented in three different forms related to the targets, namely, without any change, with re-syllabified codas, and with nasalised codas, there were no significant differences in facilitation among the three forms. Alternatively, it is also possible that participants may not have had sufficient time to process the primes up to the point that re-syllabification or nasalisation could have been carried out. In addition, the results of a Stroop task demonstrated that the onset phoneme effect was not driven by any orthographic influence. These findings suggest that the onset segment and not the syllable is the initial (or proximate) phonological unit used in the segment-to-frame encoding process during speech planning in Korean.

Phonological activation of category coordinates in spoken word production: Evidence for cascaded processing in English but not in Mandarin

ABSTRACTA central issue in spoken word production concerns how activation is transmitted from semantic to phonological levels. Recent evidence from studies of speakers of Western languages supports a cascaded view, according to which under certain circumstances, lexical candidates other than the target can activate their corresponding phonological properties. In the current study, we investigated possible differences between English and Mandarin speakers concerning the degree of cascadedness in the production system, based on the broader recent claim that properties of word form encoding might differ according to languages. With English speakers (Experiment 1), we found that when activation of targets and semantic competitors was boosted via a manipulation of semantic context, then concurrently presented “mediated” distractor words (which were phonologically related to a semantic competitor) generated interference. However, no such mediated priming was found in a parallel experiment with Chinese materials and Mandarin speakers (Experiment 2). These results suggest potential fundamental differences across the target languages in how activation is transmitted during lexical access.

The influence of the native language on phonological preparation in spoken word production in a second language

Abstract Three experiments investigated the phonological preparation unit in planning English spoken words, comparing English monolinguals, native Chinese and Japanese-speakers who spoke English as their second language. All three groups named pictures in English, and the names could either share the same initial phoneme, mora, or syllable, or had no systematic commonality. A phoneme preparation effect was shown among English monolinguals but not among the two bilingual groups, suggesting that the phoneme is the phonological preparation unit for English monolinguals, but not for the two bilingual groups. All three groups showed mora and syllable preparation effects, but further analysis and a follow-up experiment suggested that Chinese-English bilinguals may treat morae as open syllables. English monolinguals showed similar phoneme and mora preparation effect sizes, possibly as a result of flexibility. Together, the selection of phonological preparation could be flexible, influenced by both the nature of the target language and speakers’ language experiences.

The shape of things to come in speech production: Visual form interference during lexical access.

Naming a picture is slower in categorically related compared with unrelated contexts, an effect termed semantic interference. This effect has informed the development of all contemporary models of lexical access in speech production. However, category members typically share visual features, so semantic interference might in part reflect this confound. Surprisingly, little work has addressed this issue, and the relative absence of evidence for visual form interference has been proposed to be problematic for production models implementing competitive lexical selection mechanisms. In a series of five experiments using two different naming paradigms, we demonstrate a reliable visual form interference effect in the absence of a category relation and show the effect is more likely to originate during lexical or later response selection than during perceptual/conceptual processing. We conclude visual form interference in naming is a significant complicating factor for studies of semantic interference effects and discuss the implications for current accounts of lexical access in spoken word production.

The footprint of semantic and phonological interference in picture naming in aphasia: Preliminary evidence from ERP

The footprint of semantic and phonological interference in picture naming in aphasia: Preliminary evidence from ERP