Language production and working memory: The case of subject-verb agreement

The role of minority language bilingualism in spotting agreement attraction errors: Evidence from Italian varieties

Bilingual adaptations remain a subject of ongoing debate, with varying results reported across cognitive domains. A possible way to disentangle the apparent inconsistency of results is to focus on the domain of language processing, which is what the bilingual experience boils down to. This study delves into the role of the bilingual experience on the processing of agreement mismatches. Given the underrepresentation of minority bilingual speakers of non-standard varieties, we advance a unique comparative perspective that includes monolinguals, standard language bilinguals, and different groups of minority language bilinguals, taking advantage of the rich linguistic diversity of the Italian peninsula. This comparative approach can reveal the impact of various sociolinguistic aspects of the bilingual experience across different bilingual trajectories. We developed an auditory acceptability judgement task in Italian, featuring Subject-Verb agreement mismatches. Participants evaluated the stimuli on a 5-point Likert scale and reaction times were recorded. The results do not reveal significant differences between the speakers of standard languages: Italian monolinguals and Italian-Spanish bilinguals. Instead, significant differences are found between monolinguals and the two groups of minority language bidialectals, as well as between the bidialectal groups themselves: Italian-Pavese bidialectals were faster than both Italian-Agrigentino bidialectals and Italian monolinguals, while Italian-Agrigentino bidialectals were less accurate than both Italian-Pavese bidialectals and Italian monolinguals. This intricate picture is explained through variables associated with second language use and language switching. Our findings suggest that if bilingualism is viewed as a yes/no phenotype, it is unavoidable that the bilingual experience will remain a mystery linked to intensely debated results. If, however, one accepts that bilingual adaptations are shaped by the environmental ecology of each trajectory, variation across bilingual processing outcomes is unsurprising. Overall, we argue that specific sociolinguistic factors behind each bilingual experience can reveal where bilingual adaptations on language and cognition stem from.

The Role of Working Memory, Short-Term Memory, Speed of Processing, Education, and Locality in Verb-Related Morphosyntactic Production: Evidence From Greek

This study investigates the relationship between verb-related morphosyntactic production (VRMP) and locality (i.e., critical cue being adjacent to the target or not), verbal Working Memory (vWM), nonverbal/visuospatial WM (nvWM), verbal short-term memory (vSTM), nonverbal/visuospatial STM (nvSTM), speed of processing, and education. Eighty healthy middle-aged and older Greek-speaking participants were administered a sentence completion task tapping into production of subject–verb Agreement, Time Reference/Tense, and grammatical Aspect in local and nonlocal configurations, and cognitive tasks tapping into vSTM, nvSTM, vWM, nvWM, and speed of processing. Aspect elicited worse performance than Time Reference and Agreement, and Time Reference elicited worse performance than Agreement. There were main effects of vSTM, vWM, education, and locality: the greater the participants’ vSTM/vWM capacity, and the higher their educational level, the better their VRMP; nonlocal configurations elicited worse performance on VRMP than local configurations. Moreover, vWM affected Aspect and Time Reference/Tense more than Agreement, and education affected VRMP more in local than in nonlocal configurations. Lastly, locality affected Agreement and Aspect (with nonlocal configurations eliciting more agreement and aspect errors than local configurations) but not Time Reference. That vSTM/vWM (but not nvSTM/nvWM) were found to subserve VRMP suggests that VRMP is predominantly supported by domain-specific, not by domain-general, memory resources. The main effects of vWM and vSTM suggest that both the processing and storage components of WM are relevant to VRMP. That vWM (but not vSTM) interacts with production of Aspect, Time Reference, and Agreement suggests that Aspect and Time Reference are computationally more demanding than Agreement. These findings are consistent with earlier findings that, in individuals with aphasia, vWM interacts with production of Aspect, Time Reference, and Agreement. The differential effect of education on VRMP in local vs. nonlocal configurations could be accounted for by assuming that education is a proxy for an assumed procedural memory system that is sensitive to frequency patterns in language and better supports VRMP in more frequent than in less frequent configurations. In the same vein, the interaction between locality and the three morphosyntactic categories might reflect the statistical distribution of local vs. nonlocal Aspect, Agreement, and Time Reference/Tense in Greek.

Good-enough language production

Our ability to comprehend and produce language is one of humans' most impressive skills, but it is not flawless. We must convey and interpret messages via a noisy channel in ever-changing contexts and we sometimes fail to access an optimal combination of words and grammatical constructions. Here, we extend the notion of good-enough (GN) comprehension to GN production, which allows us to unify a wide range of phenomena including overly vague word choices, agreement errors, resumptive pronouns, transfer effects, and children's overextensions and regularizations. We suggest these all involve the accessing and production of a 'GN' option when a more-optimal option is inaccessible. The role of accessibility highlights the need to relate memory encoding and retrieval processes to language comprehension and production.

PIPS: A Parallel Planning Model of Sentence Production

Subject-verb agreement errors are common in sentence production. Many studies have used experimental paradigms targeting the production of subject-verb agreement from a sentence preamble (The key to the cabinets) and eliciting verb errors (… *were shiny). Through reanalysis of previous data (50 experiments; 102,369 observations), we show that this paradigm also results in many errors in preamble repetition, particularly of local noun number (The key to the *cabinet). We explore the mechanisms of both errors in parallelism in producing syntax (PIPS), a model in the Gradient Symbolic Computation framework. PIPS models sentence production using a continuous-state stochastic dynamical system that optimizes grammatical constraints (shaped by previous experience) over vector representations of symbolic structures. At intermediate stages in the computation, grammatical constraints allow multiple competing parses to be partially activated, resulting in stable but transient conjunctive blend states. In the context of the preamble completion task, memory constraints reduce the strength of the target structure, allowing for co-activation of non-target parses where the local noun controls the verb (notional agreement and locally agreeing relative clauses) and non-target parses that include structural constituents with contrasting number specifications (e.g., plural instead of singular local noun). Simulations of the preamble completion task reveal that these partially activated non-target parses, as well the need to balance accurate encoding of lexical and syntactic aspects of the prompt, result in errors. In other words: Because sentence processing is embedded in a processor with finite memory and prior experience with production, interference from non-target production plans causes errors.

Subject–Verb Number Agreement in Bilingual Processing: (Lack of) Age of Acquisition and Proficiency Effects

Children acquire language more easily than adults, though it is controversial whether this faculty declines as a result of a critical period or something else. To address this question, we investigate the role of age of acquisition and proficiency on morphosyntactic processing in adult monolinguals and bilinguals. Spanish monolinguals and intermediate and advanced early and late bilinguals of Spanish read sentences with adjacent subject–verb number agreements and violations and chose one of four pictures. Eye-tracking data revealed that all groups were sensitive to the violations and attended more to more salient plural and preterit verbs than less obvious singular and present verbs, regardless of AoA and proficiency level. We conclude that the processing of adjacent SV agreement depends on perceptual salience and language use, rather than AoA or proficiency. These findings support usage-based theories of language acquisition.

Speech fluency in bilinguals who stutter: Language proficiency and attentional demands as mediating factors

PURPOSE

The current study examines how speech disfluencies manifest themselves in the two languages of bilingual persons who stutter, starting from the hypothesis that stuttering is associated with an attentional deficit at the level of speech production.

METHODS

Twenty-eight bilingual people who stutter performed a spontaneous and a controlled speech production task, once in their dominant and once in their non-dominant language. The controlled production task (i.e. a network description task) was carried out once under a full-attention condition and once under a divided-attention condition where a non-linguistic, pitch discrimination task was performed simultaneously.

RESULTS

In both the spontaneous and the controlled speech task, bilingual persons who stutter produced more (typical and stuttering-like) disfluencies in their L2 than in their L1. Furthermore, whereas the typical disfluencies increased when attention was directed away from speech production, stuttering-like disfluencies decreased. This effect was however restricted to L2. In addition, L2 proficiency was generally found to be a predicting factor, with higher proficiency leading to fewer disfluencies.

CONCLUSIONS

These results suggest that speaking in a non-dominant language increases both typical and stuttering-like disfluencies in bilingual persons who stutter, but also that these two types of dysfluencies differ regarding their attentional origins. Our findings offer further support for attentional accounts of stuttering and have both theoretical and clinical implications.

Effects of Long-Term Language Use Experience in Sentence Processing: Evidence from Korean

Attraction effects arise when a comprehender erroneously retrieves a distractor instead of a target item during memory retrieval operations. In Korean, considerable processing difficulties occur in the agreement relation checking between a subject and an honorific-marked predicate when an intervening distractor carries a non-honorific feature. We investigate how attraction effects are managed during the processing of Korean subject-predicate honorific agreement by two Korean-speaking groups with different language use experience backgrounds: college students and airline workers. Results showed that both groups demonstrated stable knowledge of the honorific agreement in the acceptability judgment task. In the self-paced reading task, the airline group, who used honorifics extensively in their workplace, was less affected by the attraction effect than the student group. Our findings suggest that long-term language use experience can modulate how language users manage potential influence from attraction effects in real-time sentence processing.

Amyloid beta associations with connected speech in cognitively unimpaired adults

INTRODUCTION

Connected speech and language (CSL) decline has been associated with early cognitive decline, but associations between CSL and Alzheimer's disease (AD) biomarkers remain a gap in the literature. Our goal was to examine associations with amyloid beta (Aβ) and longitudinal CSL trajectories in cognitively unimpaired adults at increased AD risk.

METHODS

Using data from the Wisconsin Registry for Alzheimer's Prevention, CSL measures were automatically extracted from digitally recorded picture descriptions. Positron emission tomography determined Aβ status. Linear mixed effects models assessed the interaction between age and Aβ on CSL trajectories.

RESULTS

Participants who were Aβ positive experienced more rapid decline on specific word content, when controlling for age, sex, and literacy. There were no differences between groups in lexical diversity measures over time.

DISCUSSION

These results indicate that declines in connected speech may be related to preclinical AD. CSL may be a promising, inexpensive, and easy-to-collect digital cognitive marker for AD studies.

A Cross-Linguistic Study of Individual Differences in Speech Planning

Although previous research has shown that there exist individual and cross-linguistic differences in planning strategies during language production, little is known about how such individual differences might vary depending on which language a speaker is planning. The present series of studies examines individual differences in planning strategies exhibited by speakers of American English, French, and German. Participants were asked to describe images on a computer monitor while their eye movements were monitored. In addition, we measured participants' working memory capacity and speed of processing. The results indicate that in the present study, English and German were planned less incrementally (further in advance) prior to speech onset compared to French, which was planned more incrementally (not as far in advance). Crucially, speed of processing predicted the scope of planning for French speakers, but not for English or German speakers. These results suggest that the different planning strategies that are invoked by syntactic choices available in different languages are associated with the tendency for speakers to rely on different cognitive support systems as they plan sentences.

The Girl Was Watered by the Flower: Effects of Working Memory Loads on Syntactic Production in Young Children

Working memory is necessary for a wide variety of cognitive abilities. Developmental work has shown that as working memory capacities increase, so does the ability to successfully perform other cognitive tasks, including language processing. The present work demonstrates effects of working memory availability on children's language production. Whereas most of the previous research linking working memory to language development has been correlational, we experimentally varied the working memory load during concurrent language production in children 4-5 years old. Participants in one experiment were asked to describe simple picture scenes that had recently been described for them in the relatively unfamiliar, passive voice (e.g., the flower was watered by the girl). Children frequently produced the passive voice, a form of syntactic priming. These responses were performed while children sometimes retained a visual-spatial or auditory-verbal working memory load to be recalled after sentence production but there was no effect of the load on syntactic priming. In a second experiment, children were instructed to repeat the recently-heard passive-voice descriptions of the pictures verbatim. Surprisingly, under a load, children more often used the passive voice as they were instructed to do, but at the expense of producing additional semantic and grammatical errors (including some nonsensical renditions such as the girl was watered by the flower). We propose that working memory, when available, is used to impose a quality-control process whereby the semantic fidelity of the response to the stimulus picture is preserved, here at the expense of disregarding the experimental instruction to reproduce the passive voice.

The Meeting Point: Where Language Production and Working Memory Share Resources

The interaction between working memory and language processing is widely discussed in cognitive research. However, those studies often explore the relationship between language comprehension and working memory (WM). The role of WM is rarely considered in language production, despite some evidence suggesting a relationship between the two cognitive systems. This study attempts to fill that gap by using a complex span task during language production. We make our predictions based on the reorganization of elementary functions neurocognitive model, a usage based theory about grammatical status, and language production models. In accordance with these theories, we expect an overlap between language production and WM at one or more levels of language planning. Our results show that WM is involved at the phonological encoding level of language production and that adding WM load facilitates language production, which leads us to suggest that an extra task-specific storage is being created while the task is performed.

Individual differences in the production of disfluency: A latent variable analysis of memory ability and verbal intelligence

Recent work has begun to focus on the role that individual differences in executive function and intelligence have on the production of fluent speech. However, isolating the underlying causes of different types of disfluency has been difficult given the speed and complexity of language production. In this study, we focused on the role of memory abilities and verbal intelligence, and we chose a task that relied heavily on memory for successful performance. Given the task demands, we hypothesised that a substantial proportion of disfluencies would be due to memory retrieval problems. We contrasted memory abilities with individual differences in verbal intelligence as previous work highlighted verbal intelligence as an important factor in disfluency production. A total of 78 participants memorised and repeated 40 syntactically complex sentences, which were recorded and coded for disfluencies. Model comparisons were carried out using hierarchical structural equation modelling. Results showed that repetitions were significantly related to verbal intelligence. Unfilled pauses and repairs, in contrast, were marginally ( p < .09) related to memory abilities. The relationship in all cases was negative. Conclusions explore the link between different types of disfluency and particular problems arising in the course of production, and how individual differences inform theoretical debates in language production.

Morphosyntactic Production and Verbal Working Memory: Evidence From Greek Aphasia and Healthy Aging

PURPOSE

The present work investigated whether verbal working memory (WM) affects morphosyntactic production in configurations that do not involve or favor similarity-based interference and whether WM interacts with verb-related morphosyntactic categories and/or cue-target distance (locality). It also explored whether the findings related to the questions above lend support to a recent account of agrammatic morphosyntactic production: Interpretable Features' Impairment Hypothesis (Fyndanis, Varlokosta, & Tsapkini, 2012).

METHOD

A sentence completion task testing production of subject-verb agreement, tense/time reference, and aspect in local and nonlocal conditions and two verbal WM tasks were administered to 8 Greek-speaking persons with agrammatic aphasia (PWA) and 103 healthy participants.

RESULTS

The 3 morphosyntactic categories dissociated in both groups (agreement > tense > aspect). A significant interaction emerged in both groups between the 3 morphosyntactic categories and WM. There was no main effect of locality in either of the 2 groups. At the individual level, all 8 PWA exhibited dissociations between agreement, tense, and aspect, and effects of locality were contradictory.

CONCLUSIONS

Results suggest that individuals with WM limitations (both PWA and healthy older speakers) show dissociations between the production of verb-related morphosyntactic categories. WM affects performance shaping the pattern of morphosyntactic production (in Greek: subject-verb agreement > tense > aspect). The absence of an effect of locality suggests that executive capacities tapped by WM tasks are involved in morphosyntactic processing of demanding categories even when the cue is adjacent to the target. Results are consistent with the Interpretable Features' Impairment Hypothesis (Fyndanis et al., 2012).

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.6024428.

The interaction of notional number and morphophonology in subject-verb agreement: A role for working memory

Research shows that cross-linguistically, subject-verb agreement with complex noun phrases (e.g., The label on the bottles) is influenced by notional number and the presence of homophony in case, gender, or number morphology. Less well-understood is whether notional number and morphophonology interact during speech production, and whether the relative impact of these two factors is influenced by working memory capacity. Using an auditory sentence completion task, we investigated the impact of notional number and morphophonology on agreement with complex subject noun phrases in Dutch. Results revealed main effects of notional number and morphophonology. Critically, there was also an interaction between morphophonology and notional number because participants showed greater notional effects when the determiners were homophonous and morphophonologically ambiguous. Furthermore, participants with higher working memory scores made fewer agreement errors when the subject noun phrase contained homophonous determiners, and this effect was greater when the subject noun phrase was notionally singular. These findings support the hypothesis that cue-based retrieval plays a role in agreement production, and suggests that the ability to correctly assign subject-verb agreement-especially in the presence of homophonous determiners-is modulated by working memory capacity.

Declines in Connected Language Are Associated with Very Early Mild Cognitive Impairment: Results from the Wisconsin Registry for Alzheimer's Prevention

Changes to everyday spoken language ("connected language") are evident in persons with AD dementia, yet little is known about when these changes are first detectable on the continuum of cognitive decline. The aim of this study was to determine if participants with very early, subclinical memory declines were also showing declines in connected language. We analyzed connected language samples obtained from a simple picture description task at two time points in 264 participants from the Wisconsin Registry for Alzheimer's Prevention (WRAP). In parallel, participants were classified as either "Cognitively Healthy" or "Early Mild Cognitive Impairment" based on longitudinal neuropsychological test performance. Linear mixed effects models were used to analyze language parameters that were extracted from the connected language samples using automated feature extraction. Participants with eMCI status declined faster in features of speech fluency and semantic content than those who were cognitively stable. Measures of lexical diversity and grammatical complexity were not associated with eMCI status in this group. These findings provide novel insights about the relationship between cognitive decline and everyday language, using a quick, inexpensive, and performance-based method.

Investigating the origin of nonfluency in aphasia: A path modeling approach to neuropsychology

A major challenge in understanding the origin of clinical symptoms in neuropsychological impairments is capturing the complexity of the underlying cognitive structure. This paper presents a practical guide to path modeling, a statistical approach that is well-suited for modeling multivariate outcomes with a multi-factorial origin. We discuss a step-by-step application of such a model to the problem of nonfluency in aphasia. Individuals with aphasia are often classified into fluent and nonfluent groups for both clinical and research purposes, but despite a large body of research on the topic, the origin of nonfluency remains obscure. We propose a model of nonfluency inspired by the psycholinguistic approach to sentence production, review several bodies of work that have independently suggested a relationship between fluency and various elements in this model, and implement it using path modeling on data from 112 individuals with aphasia from the AphasiaBank. The results show that word production, comprehension, and working memory deficits all contribute to nonfluency, in addition to syntactic impairment which has a strong and direct impact on fluency. More generally, we demonstrate that a path model is an excellent tool for exploring complex neuropsychological symptoms such as nonfluency.

The effects of utterance timing and stimulation of left prefrontal cortex on the production of referential expressions

We examined the relationship between the timing of utterance initiation and the choice of referring expressions, e.g., pronouns (it), zeros (…and went down), or descriptive NPs (the pink pentagon). We examined language production in healthy adults, and used anodal transcranial direct current stimulation (tDCS) to test the involvement of the left prefrontal cortex (PFC) in the timing of utterance production and the selection of reference forms in a discourse context. Twenty-two subjects (11 anodal, 11sham) described fast-paced actions, e.g. The gray oval flashes, then it moves right 2 blocks. We only examined trials in contexts that supported pronoun/zero use. For sham participants, pronouns/zeros increased on trials with longer latencies to initiate the target utterance, and trials where the previous trial was short. We argue that both of these conditions enabled greater message pre-planning and greater discourse connectedness: The strongest predictor of pronoun/zero usage was the presence of a connector word like and or then, which was also tended to occur on trials with longer latencies. For the anodal participants, the latency effect disappeared. PFC stimulation appeared to enable participants to produce utterances with greater discourse connectedness, even while planning incrementally.

The role of executive control in resolving grammatical number conflict in sentence comprehension

In sentences with a complex subject noun phrase, like "The key to the cabinets is lost", the grammatical number of the head noun (key) may be the same or different from that of the modifier noun phrase (cabinets). When the number is the same, comprehension is usually easier than when it is different. Grammatical number computation may occur while processing the modifier noun (integration phase) or while processing the verb (checking phase). We investigated at which phase number conflict and plausibility of the modifier noun as subject for the verb affect processing, and we imposed a gaze-contingent tone discrimination task in either phase to test whether number computation involves executive control. At both phases, gaze durations were longer when a concurrent tone task was present. Additionally, at the integration phase, gaze durations were longer under number conflict, and this effect was enhanced by the presence of a tone task, whereas no effects of plausibility of the modifier were observed. The finding that the effect of number match was larger under load shows that computation of the grammatical number of the complex noun phrase requires executive control in the integration phase, but not in the checking phase.

The dynamics of variation in individuals

This paper examines the factors conditioning the production of linguistic variables in real time by individual speakers: the study of what we term the dynamics of variation in individuals. We propose a framework that recognizes three types of factors conditioning variation: sociostylistic (s-), internal linguistic (i-), and psychophysiological (p-). We develop two main points against this background. The first is that sequences of variants produced by individuals display systematic patterns that can be understood in terms of s-conditioning and p-conditioning (with a focus on the latter). The second main point is that p-conditioning and i-conditioning are distinct in their mental implementations; this claim has implications for understanding the locality of the factors conditioning alternations, for the universality and language-specificity of variation, and for the general question of whether grammar and language use are distinct. Throughout the paper, questions about the dynamics of variation in individuals are set against the typical community-centered variationist perspective, with an eye towards showing how findings in the two domains, though differing in explanatory focus, can ultimately be mutually informative.

Core-Lexicon and Main-Concept Production During Picture-Sequence Description in Adults Without Brain Damage and Adults With Aphasia

PURPOSE

We sought to identify the core lexicon of a picture-description task using transcripts from the AphasiaBank database and to determine differences in core-lexicon usage between control speakers and persons with aphasia (PWAs). We also investigated the relationship between core lexicon and an established discourse measure, main-concept analysis.

METHOD

A core lexicon was developed by identifying lemmas produced by 92 control speakers. Transcripts were scored-165 control transcripts and 238 PWA transcripts-using the core lexicon and a recently developed main-concept list. Median tests examined differences between controls, PWAs, and aphasia subtypes. Spearman's correlations assessed the relationship between core-lexicon and main-concept performance.

RESULTS

A 24-item core lexicon was identified. Significant differences were found between control speakers and PWAs, and between aphasia subtypes, for core-lexicon and main-concept scores. Core-lexicon and main-concept performance was significantly and positively correlated for all groups.

CONCLUSIONS

We report the development of a core lexicon, differences in core-lexicon usage between speakers, and the relationship between core-lexicon and main-concept scores. Research is needed to determine the clinical utility and psychometric properties of these discourse measures and their potential contribution to multilevel discourse analysis of functional communication.

Effects of acute hypoglycemia on working memory and language processing in adults with and without type 1 diabetes

OBJECTIVE

To examine the effects of hypoglycemia on language processing in adults with and without type 1 diabetes.

RESEARCH DESIGN AND METHODS

Forty adults were studied (20 with type 1 diabetes and 20 healthy volunteers) using a hyperinsulinemic glucose clamp to lower blood glucose to 2.5 mmol/L (45 mg/dL) (hypoglycemia) for 60 min, or to maintain blood glucose at 4.5 mmol/L (81 mg/dL) (euglycemia), on separate occasions. Language tests were applied to assess the effects of hypoglycemia on the relationship between working memory and language (reading span), grammatical decoding (self-paced reading), and grammatical encoding (subject-verb agreement).

RESULTS

Hypoglycemia caused a significant deterioration in reading span (P < 0.001; η(2) = 0.37; Cohen d = 0.65) and a fall in correct responses (P = 0.005; η(2) = 0.19; Cohen d = 0.41). On the self-paced reading test, the reading time for the first sentence fragment increased during hypoglycemia (P = 0.039; η(2) = 0.11; Cohen d = 0.25). For the reading of the next fragment, hypoglycemia affected the healthy volunteer group more than the adults with type 1 diabetes (P = 0.03; η(2) = 0.12; Cohen d = 0.25). However, hypoglycemia did not significantly affect the number of errors in sentence comprehension or the time taken to answer questions. Hypoglycemia caused a deterioration of subject-verb agreement (correct responses: P = 0.011; η(2) = 0.159; Cohen d = 0.31).

CONCLUSIONS

Hypoglycemia caused a significant deterioration in reading span and in the accuracy of subject-verb agreement, both of which are practical aspects of language involved in its everyday use. Language processing is therefore impaired during moderate hypoglycemia.

Verb production tasks in the measurement of communicative abilities in aphasia

BACKGROUND

The neurofunctional correlates of verbs and nouns have been the focus of many theoretically oriented studies. In clinical practice, however, more attention is typically paid to nouns, and the relative usefulness of tasks probing nouns and verbs is unclear. The routine administration of tasks that use verbs could be a relevant addition to current batteries. Evaluating performance on both noun and verb tasks may provide a more reliable account of everyday language abilities than an evaluation restricted to nouns.

AIMS

To assess the benefits of administering verb tasks in addition to noun tasks, and their relation to three functional measures of language.

METHOD AND PROCEDURE

Twenty-one subjects with poststroke language disorders completed four picture-naming tasks and a role-playing test (Communicative Abilities in Daily Living, Second Edition, CADL-2), commonly used as measure of everyday language abilities. Two questionnaires (Communicative Effectiveness Index, CETI, and Communicative Activity Log, CAL) were completed by caregivers. Picture-naming tasks were matched for psycholinguistic variables to avoid lexicosemantic and morphosyntactic confounds.

RESULTS

No significant differences emerged across picture-naming tasks. Scores on the role-playing test and the two questionnaires differed; scores between the two questionnaires did not. The four naming tasks correlated significantly with CADL-2, CETI, and CAL. The strength of the correlation with CADL-2 was significantly greater for Naming Finite Verbs than for Object Naming. Thirteen participants showed no differences in performance between tasks, 6 fared significantly worse on verb tasks than on Object Naming, 1 fared better at Naming Finite Verbs though his performance was poor overall, and 1 was significantly more impaired on verbs.

CONCLUSIONS

Performance on tasks that use verbs, and especially Naming Finite Verbs, may provide a more accurate estimate of language abilities in daily living than Object Naming alone. Administering both verb and noun tasks may be recommended in clinical practice.

Native language influence on the distributive effect in producing second language subject-verb agreement

Three experiments were conducted to investigate the distributive effect when producing subject-verb agreement in English as a second language (L2) when the participant's first language either does or does not require subject-verb agreement. Both Chinese-English and Uygur-English bilinguals were included in Experiment 1. Chinese has no required subject-verb agreement, whereas Uygur does. Results showed that the distributive effect was observed in Uygur-English bilinguals but not in Chinese-English bilinguals, indicating that this particular first language (L1) syntactic feature is one significant factor affecting the distributive effect in the production of subject-verb agreement in L2. Experiment 2 further investigated the matter by choosing Chinese-English participants with higher L2 proficiency. Still, no distributive effect was observed, suggesting that the absence of distributive effect in Chinese-English bilinguals in Experiment 1 was not due to low proficiency in the target language. Experiment 3 changed the way the stimuli were presented, highlighting the singular or distributive nature of the subject noun phrases, and the distributive effect was observed in Chinese-English bilinguals. Altogether, the results show that the L1 syntactic feature of subject-verb agreement is one significant factor affecting the distributive effect in the production of subject-verb agreement in L2. More specifically, distributive effects rarely occur in L2 when L1 has no requirement on subject-verb agreement, whereas distributive effects are more likely to occur in L2 when the L1 also has required subject-verb agreement.

Keeping it simple: studying grammatical encoding with lexically reduced item sets

Compared to the large body of work on lexical access, little research has been done on grammatical encoding in language production. An exception is the generation of subject-verb agreement. Here, two key findings have been reported: (1) speakers make more agreement errors when the head and local noun of a phrase mismatch in number than when they match [e.g., the key to the cabinet(s)]; and (2) this attraction effect is asymmetric, with stronger attraction for singular than for plural head nouns. Although these findings are robust, the cognitive processes leading to agreement errors and their significance for the generation of correct agreement are not fully understood. We propose that future studies of agreement, and grammatical encoding in general, may benefit from using paradigms that tightly control the variability of the lexical content of the material. We report two experiments illustrating this approach. In both of them, the experimental items featured combinations of four nouns, four color adjectives, and two prepositions. In Experiment 1, native speakers of Dutch described pictures in sentences such as the circle next to the stars is blue. In Experiment 2, they carried out a forced-choice task, where they read subject noun phrases (e.g., the circle next to the stars) and selected the correct verb-phrase (is blue or are blue) with a button press. Both experiments showed an attraction effect, with more errors after subject phrases with mismatching, compared to matching head and local nouns. This effect was stronger for singular than plural heads, replicating the attraction asymmetry. In contrast, the response times recorded in Experiment 2 showed similar attraction effects for singular and plural head nouns. These results demonstrate that critical agreement phenomena can be elicited reliably in lexically reduced contexts. We discuss the theoretical implications of the findings and the potential and limitations of studies using lexically simple materials.

Verbal working memory predicts co-speech gesture: evidence from individual differences

Gesture facilitates language production, but there is debate surrounding its exact role. It has been argued that gestures lighten the load on verbal working memory (VWM; Goldin-Meadow, Nusbaum, Kelly, & Wagner, 2001), but gestures have also been argued to aid in lexical retrieval (Krauss, 1998). In the current study, 50 speakers completed an individual differences battery that included measures of VWM and lexical retrieval. To elicit gesture, each speaker described short cartoon clips immediately after viewing. Measures of lexical retrieval did not predict spontaneous gesture rates, but lower VWM was associated with higher gesture rates, suggesting that gestures can facilitate language production by supporting VWM when resources are taxed. These data also suggest that individual variability in the propensity to gesture is partly linked to cognitive capacities.

Ways of looking ahead: hierarchical planning in language production

It is generally assumed that language production proceeds incrementally, with chunks of linguistic structure planned ahead of speech. Extensive research has examined the scope of language production and suggests that the size of planned chunks varies across contexts (Ferreira & Swets, 2002; Wagner & Jescheniak, 2010). By contrast, relatively little is known about the structure of advance planning, specifically whether planning proceeds incrementally according to the surface structure of the utterance, or whether speakers plan according to the hierarchical relationships between utterance elements. In two experiments, we examine the structure and scope of lexical planning in language production using a picture description task. Analyses of speech onset times and word durations show that speakers engage in hierarchical planning such that structurally dependent lexical items are planned together and that hierarchical planning occurs for both direct and indirect dependencies.

The use of subject-verb agreement and verb argument structure in monolingual and bilingual children with specific language impairment

This study investigates the use of subject-verb agreement and verb argument structure in the spoken Dutch of monolingual Dutch children with specific language impairment (SLI) and bilingual Frisian-Dutch children with SLI. Both SLI groups appeared to be less efficient in their use of subject-verb agreement and verb argument structure than the control group (consisting of monolingual typically developing Dutch children matched on mean length of utterance in morphemes) in that they showed significantly more agreement errors as well as a relation between verb agreement structure complexity and omission, a relation that the typically developing children failed to show. Furthermore, no significant differences were found between the monolingual and the bilingual SLI group. These findings indicate that subject-verb agreement and verb argument structure are both affected in SLI, but not more severely in bilinguals than in monolinguals.

Real-time production of arguments and adjuncts in normal and agrammatic speakers

Two eyetracking experiments examined the real-time production of verb arguments and adjuncts in healthy and agrammatic aphasic speakers. Verb argument structure has been suggested to play an important role during grammatical encoding (Bock & Levelt, 1994) and in speech deficits of agrammatic aphasic speakers (Thompson, 2003). However, little is known about how adjuncts are processed during sentence production. The present experiments measured eye movements while speakers were producing sentences with a goal argument (e.g., the mother is applying lotion to the baby) and a beneficiary adjunct phrase (e.g., the mother is choosing lotion for the baby) using a set of computer-displayed written words. Results showed that the sentence production system experiences greater processing cost for producing adjuncts than verb arguments and this distinction is preserved even after brain-damage. In Experiment 1, healthy young speakers showed greater gaze durations and gaze shifts for adjuncts as compared to arguments. The same patterns were found in agrammatic and older speakers in Experiment 2. Interestingly, the three groups of speakers showed different time courses for encoding adjuncts: young speakers showed greater processing cost for adjuncts during speech, consistent with incremental production (Kempen & Hoenkamp, 1987). Older speakers showed this difference both before speech onset and during speech, while aphasic speakers appeared to preplan adjuncts before speech onset. These findings suggest that the degree of incrementality may be affected by speakers' linguistic capacity.

High-level language production in Parkinson's disease: a review

This paper discusses impairments of high-level, complex language production in Parkinson's disease (PD), defined as sentence and discourse production, and situates these impairments within the framework of current psycholinguistic theories of language production. The paper comprises three major sections, an overview of the effects of PD on the brain and cognition, a review of the literature on language production in PD, and a discussion of the stages of the language production process that are impaired in PD. Overall, the literature converges on a few common characteristics of language production in PD: reduced information content, impaired grammaticality, disrupted fluency, and reduced syntactic complexity. Many studies also document the strong impact of differences in cognitive ability on language production. Based on the data, PD affects all stages of language production including conceptualization and functional and positional processing. Furthermore, impairments at all stages appear to be exacerbated by impairments in cognitive abilities.

Processing subject-verb agreement in a second language depends on proficiency

Subject-verb agreement is a computation that is often difficult to execute perfectly in the first language (L1) and even more difficult to produce skillfully in a second language (L2). In this study, we examined the way in which bilingual speakers complete sentence fragments in a manner that reflects access to both grammatical and conceptual number. In two experiments, we show that bilingual speakers are sensitive to both grammatical and conceptual number in the L1 and grammatical number agreement in the L2. However, only highly proficient bilinguals are also sensitive to conceptual number in the L2. The results suggest that the extent to which speakers are able to exploit conceptual information during speech planning depends on the level of language proficiency.

Differences in the cognitive demands of word order, plural, and subject-verb agreement constructions

The syntactic devices of subject-verb-object word order, regular plurals, and subject-verb agreement differ in age of acquisition and susceptibility to error within language-disordered populations. In the present article, the performance of adults on a grammaticality judgment task is used to explore whether such differences are related to working memory (both in terms of an externally imposed load and individual differences in capacity) and phonological ability. The results show that word order, the earliest acquired and most resilient device, is not affected by load, memory span, or phonological ability. Plurals are affected marginally by load and significantly by phonological ability. Agreement, the last acquired and least resilient device, is affected by load, memory span, and phonological ability. Thus, consistent with a processing-based explanation, later acquired and less resilient devices have higher working memory and phonological demands.

Language integration in bilingual sentence production

To what extent are processes used in sentence production integrated between the different languages of a bilingual and to what extent are they kept separate? We consider three models that differ in their assumptions about the degree of integration: De Bot's [De Bot, K. (1992). A bilingual production model: Levelt's Speaking model adapted. Applied Linguistics, 13, 1-24] bilingual blueprint of the speaker, Ullman's [Ullman, M. T. (2001). The neural basis of lexicon and grammar in first and second language: The declarative/procedural model. Bilingualism: Language and Cognition, 4, 105-122] declarative/procedural model of bilingualism, and Hartsuiker et al.'s [Hartsuiker, R. J., Pickering, M. J., & Veltkamp, E. (2004). Is syntax separate or shared between languages? Cross-linguistic syntactic priming in Spanish/English bilinguals. Psychological Science, 15, 409-414] integrated model. A review of the evidence from bilingual sentence production studies shows that Hartsuiker et al.'s predictions are supported, but argues against the other two models. We discuss some repercussions for bilingual language use.

Grammaticality judgments in children: the role of age, working memory and phonological ability

This paper examines the role of age, working memory span and phonological ability in the mastery of ten different grammatical constructions. Six- through eleven-year-old children (n=68) and adults (n=19) performed a grammaticality judgment task as well as tests of working memory capacity and receptive phonological ability. Children showed early mastery of some grammatical structures (e.g. word order, article omissions) while even the oldest children differed from adults on others (e.g. past tense, third person singular agreement). Working memory capacity and phonological ability accounted for variance in grammaticality judgments above and beyond age effects. In particular, working memory capacity correlated with structures involving verb morphology and word order; phonological ability was important for structures with low phonetic substance. Children's relative difficulty with the different constructions showed parallels to adult performance under memory load stress, indicating working memory capacity may be a limiting factor in their performance. Implications for performance by memory and phonologically impaired populations are discussed.