When having two names facilitates lexical selection: Similar results in the picture-word task from translation distractors in bilinguals and synonym distractors in monolinguals

A Meta-Analysis of Anomia Treatment in Bilingual Aphasia: Within- and Cross-Language Generalization and Predictors of the Treatment Outcomes

PURPOSE

The present meta-analysis investigated the efficacy of anomia treatment in bilingual and multilingual persons with aphasia (BPWAs) by assessing the magnitudes of six anomia treatment outcomes. Three of the treatment outcomes pertained to the "trained language": improvement of trained words (treatment effect [TE]), within-language generalization of semantically related untrained words (WLG-Related), and within-language generalization of unrelated words (WLG-Unrelated). Three treatment outcomes were for the "untrained language": improvement of translations of the trained words (cross-language generalization of trained words [CLG-Tx]), cross-language generalization of semantically related untrained words (CLG-Related), and cross-language generalization of unrelated untrained words (CLG-Unrelated). This study also examined participant- and treatment-related predictors of these treatment outcomes.

METHOD

This study is registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42023418147. Nine electronic databases were searched to identify word retrieval treatment studies of poststroke BPWAs of at least 6 months postonset. Pre- and posttreatment single-word naming scores were extracted for each eligible participant and used to calculate effect sizes (within-case Cohen's d) of the six treatment outcomes. Random-effects meta-analyses were conducted to assess weighted mean effect sizes of the treatment outcomes across studies. Multiple linear regression analyses were used to examine the effects of participant-related variables (pretreatment single-word naming and comprehension representing poststroke lexical processing abilities) and treatment-related variables (type, language, and duration). The methodological quality of eligible studies and the risk of bias in this meta-analysis were assessed.

RESULTS

A total of 17 published studies with 39 BPWAs were included in the meta-analysis. The methodological quality of the included studies ranged from fair (n = 4) to good (n = 13). Anomia treatment produced a medium effect size for TE (M = 8.36) and marginally small effect sizes for WLG-Related (M = 1.63), WLG-Unrelated (M = 0.68), and CLG-Tx (M = 1.56). Effect sizes were nonsignificant for CLG-Related and CLG-Unrelated. TE was significantly larger than the other five types of treatment outcomes. TE and WLG-Related effect sizes were larger for BPWAs with milder comprehension or naming impairments and for treatments of longer duration. WLG-Unrelated was larger when BPWAs received phonological treatment than semantic and mixed treatments. The overall risk of bias in the meta-analysis was low with a potential risk of bias present in the study identification process.

CONCLUSIONS

Current anomia treatment practices for bilingual speakers are efficacious in improving trained items but produce marginally small within-language generalization and cross-language generalization to translations of the trained items. These results highlight the need to provide treatment in each language of BPWAs and/or investigate other approaches to promote cross-language generalization. Furthermore, anomia treatment outcomes are influenced by BPWAs' poststroke single-word naming and comprehension abilities as well as treatment duration and the provision of phonological treatment.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25595712.

Multilingualism at the Market: A Pre-registered Immersive Virtual Reality Study of Bilingual Language Switching

Bilinguals, by definition, are capable of expressing themselves in more than one language. But which cognitive mechanisms allow them to switch from one language to another? Previous experimental research using the cued language-switching paradigm supports theoretical models that assume that both transient, reactive and sustained, proactive inhibitory mechanisms underlie bilinguals' capacity to flexibly and efficiently control which language they use. Here we used immersive virtual reality to test the extent to which these inhibitory mechanisms may be active when unbalanced Dutch-English bilinguals i) produce full sentences rather than individual words, ii) to a life-size addressee rather than only into a microphone, iii) using a message that is relevant to that addressee rather than communicatively irrelevant, iv) in a rich visual environment rather than in front of a computer screen. We observed a reversed language dominance paired with switch costs for the L2 but not for the L1 when participants were stand owners in a virtual marketplace and informed their monolingual customers in full sentences about the price of their fruits and vegetables. These findings strongly suggest that the subtle balance between the application of reactive and proactive inhibitory mechanisms that support bilingual language control may be different in the everyday life of a bilingual compared to in the (traditional) psycholinguistic laboratory.

Similarity-induced interference or facilitation in language production reflects representation, not selection

Researchers have long interpreted the presence or absence of semantic interference in picture naming latencies as confirming or refuting theoretical claims regarding competitive lexical selection. But inconsistent empirical results challenge any mechanistic interpretation. A behavioral experiment first verified an apparent boundary condition in a blocked picture naming task: when orthogonally manipulating association type, taxonomic associations consistently elicit interference, while thematic associations do not. A plausible representational difference is that thematic feature activations depend more on supporting contexts. Simulations show that context-sensitivity emerges from the distributional statistics that are often used to measure thematic associations: residual semantic activation facilitates the retrieval of words that share semantic features, counteracting learning-based interference, and training a production model with greater sequential cooccurrence for thematically related words causes it to acquire stronger residual activation for thematic features. Modulating residual activation, either directly or through training, allows the model to capture gradient values of interference and facilitation, and in every simulation competitive and noncompetitive selection algorithms produce qualitatively equivalent results.

Beyond the tried and true: How virtual reality, dialog setups, and a focus on multimodality can take bilingual language production research forward

Bilinguals possess the ability of expressing themselves in more than one language, and typically do so in contextually rich and dynamic settings. Theories and models have indeed long considered context factors to affect bilingual language production in many ways. However, most experimental studies in this domain have failed to fully incorporate linguistic, social, or physical context aspects, let alone combine them in the same study. Indeed, most experimental psycholinguistic research has taken place in isolated and constrained lab settings with carefully selected words or sentences, rather than under rich and naturalistic conditions. We argue that the most influential experimental paradigms in the psycholinguistic study of bilingual language production fall short of capturing the effects of context on language processing and control presupposed by prominent models. This paper therefore aims to enrich the methodological basis for investigating context aspects in current experimental paradigms and thereby move the field of bilingual language production research forward theoretically. After considering extensions of existing paradigms proposed to address context effects, we present three far-ranging innovative proposals, focusing on virtual reality, dialog situations, and multimodality in the context of bilingual language production.

Processing of Synonyms and Homographs in Bilingual and Monolingual Speakers

Bilinguals have long-lasting experience with cross-language double-mappings (i.e., translation equivalents and interlingual homographs (or false friends)). Considering this, we examined whether bilinguals differ from monolinguals in within-language double-mapping (i.e., synonyms and homographs) processing. Across two experiments, we compared performances from Spanish monolinguals and Spanish-Basque bilinguals on a behavioral picture-word matching task. The words were all presented in Spanish, the native language of all participants. Participants responded to synonyms and homographs (both double-mappings) or single-mappings (controls). The reaction times in both experiments showed clear and significant costs in processing within-language double-mapping stimuli, as well as intrinsic differences in processing homographs versus synonyms. However, these effects did not differ between bilinguals and monolinguals. The present findings thus suggest that the bilinguals' extensive experience with cross-linguistic double-mappings does not transfer onto within-language double-mapping processing.

No evidence for a mixing benefit-A registered report of voluntary dialect switching

Previous language production research with bidialectals has provided evidence for similar language control processes as during bilingual language production. In the current study, we aimed to further investigate this claim by examining bidialectals with a voluntary language switching paradigm. Research with bilinguals performing the voluntary language switching paradigm has consistently shown two effects. First, the cost of switching languages, relative to staying in the same language, is similar across the two languages. The second effect is more uniquely connected to voluntary language switching, namely a benefit when performing in mixed language blocks relative to single language blocks, which has been connected to proactive language control. While the bidialectals in this study also showed symmetrical switch costs, no mixing effect was observed. These results could be taken as evidence that bidialectal and bilingual language control are not entirely similar.

The psychological reality of picture name agreement

Picture name agreement is commonly used as both a control variable and independent variable in studies of language production. It describes the proportion of participants who volunteer a picture's modal name in a norming study-a population-level descriptor-but researchers often assume that name agreement also indexes cognitive processes that occur within individuals. For instance, if norms show that 50% of speakers name a picture as couch, then each time a person tries to name the picture, they might have a 50% chance of selecting couch. An alternative, however, is that name agreement may simply reflect population-level sampling of more stable individual preferences (e.g., 50% of speakers prefer the name couch), continually developed through experience. One way to distinguish between these possibilities - and assess the psychological reality of name agreement - is simply to re-norm pictures with the same individuals. In Experiment 1, we therefore collected timed naming norms for a large set of line drawings from the same 25 native British English speakers twice, 1-2 weeks apart. Results show participants' name choices in Session 2 are jointly predicted by population-level name agreement, from our previous norms, and individuals' own productions in Session 1. Experiment 2 replicated this result and further showed that prior selections predicted Session 3 outcomes better than those in Session 2, in line with an incremental learning account. This is the first direct demonstration that picture name agreement has some psychological validity, but also reveals that it does not directly index within-participant lexical competition as previously assumed.

Is it easier to use one language variety at a time, or mix them? An investigation of voluntary language switching with bidialectals

Previous language production research with bidialectals has provided evidence for similar language control processes as during bilingual language production. In the current study, we aim to further investigate this claim by examining bidialectals with a voluntary language switching paradigm. Research with bilinguals performing the voluntary language switching paradigm has consistently shown two effects. First, the cost of switching languages, relative to staying in the same language, is similar across the two languages. The second effect is more uniquely connected to voluntary language switching, namely a benefit when performing in mixed language blocks relative to single language blocks, which has been connected to proactive language control. If a similar pattern could be observed with bidialectals in a voluntary language switching paradigm, then this would provide additional evidence in favor of similar control processes underlying bidialectal and bilingual language production.

Within-language lexical interference can be resolved in a similar way to between-language interference

This study asks if monolinguals can resolve lexical interference within a language with mechanisms similar to those used by bilinguals to resolve interference across languages. These mechanisms are known as bilingual language control, are assumed to be at least in part top-down, and are typically studied with cued language mixing, a version of which we use here. Balanced (Experiment 1) and nonbalanced Spanish-English bilinguals (Experiment 2) named pictures in each of their languages. English monolinguals from two different American cities (Experiments 3 and 4) named pictures in English only with either basic-level (e.g., shoe) or subordinate names (e.g., sneaker). All experiments were identically structured and began with blocked naming in each language or name type, followed by trial-level switching between the two languages or name types, followed again by blocked naming. We analyzed switching, mixing and (introduced here) post-mixing costs, dominance effects and repetition benefits. In the bilingual experiments, we found some signs of dominant deprioritization, the behavioral hallmark of bilingual language control: larger costs for dominant- than for nondominant-language names. Crucially, in the monolingual experiments, we also found signs of dominant deprioritization: larger costs for basic-level than for subordinate names. Unexpectedly and only in the monolingual experiments, we also found a complete dominance reversal: Basic-level names (which otherwise behaved as dominant) were produced more slowly overall than subordinate names. Taken together, these results are hard to explain with the bottom-up mechanisms typically assumed for monolingual interference resolution. We thus conclude that top-down mechanisms might (sometimes) be involved in lexical interference resolution not only between languages but also within a language.

Two dissociable semantic mechanisms predict naming errors and their responsive brain sites in awake surgery. DO80 revisited

How do we choose words, and what affects the selection of a specific term? Naming tests such as the DO80 are frequently used to assess language function during brain mapping in awake surgery. The present study aimed to explore whether specific semantic errors become more probable under the stimulation of specific brain areas. Moreover, it meant to determine whether specific semantic characteristics of the items may evoke specific types of error. A corpus-based qualitative semantic analysis of the DO80 items, and the emitted naming errors to those items during direct cortical electrostimulation (DCE) revealed that the number of hyperonyms (i.e. 'vehicle' for car') of an item predicted the emission of a synonym ('automobile' for 'car'). This association occurred mainly in frontal tumor patients, which was corroborated by behavior to lesion analyses. In contrast, the emission of co-hyponyms was associated with tumors located in temporal areas. These two behavior-lesion associations thus dissociated, and were also dependent on item semantic characteristics. Co-hyponym errors might generate from the disruption in a temporal semantic-to-lexical process, and the production of synonyms could be the result of an impairment in a frontal lexical-selection mechanism. A hypothesis on the lexical selection mechanisms exerted by the inferior frontal gyrus is proposed. Crucially, the present data suggest the need for more restrictive naming tasks, with items conditioned by tumor location.

Translation Distractors Facilitate Production in Single- and Mixed-Language Picture Naming

In the picture-word interference (PWI) task, semantically related distractors slow production, while translation-equivalent distractors speed it, possibly implying a language-specific bilingual production system (Costa, Miozzo & Caramazza, 1999). However, in most previous PWI studies bilinguals responded in just one language, an artificial task restriction. We investigated translation facilitation effects in PWI with language switching. Spanish-English bilinguals named pictures in single- or mixed-language-response blocks, with distractors in the target language (Experiment 1), or in the non-target language (Experiment 2). Both experiments replicated previously reported translation facilitation effects in both single-language and mixed-language-response blocks. However, language dominance was reversed in mixed-language response blocks, implying inhibition of the dominant language and competition between languages. These results may be explained by a language non-specific selection model in which bilinguals do not restrict selection to one language, with translation facilitation being caused by facilitation at the semantic level offsetting competition at the lexical level.

Do elevators compete with lifts?: Selecting dialect alternatives

Recently, Melinger (2018) demonstrated that translation equivalent dialectal words compete for selection in a way that translation equivalent words from a non-target language do not. She argued that dialectal words are stored as within-language representations. However, Dylman and Barry (2018) showed that within-language synonyms behave like between-language translation equivalents, calling Melinger's interpretation into question. The aim of the present study is to compare dialectal and non-dialectal synonyms distractor effects with the same experimental design to elaborate our understanding of how dialectal lexical items are stored and retrieved during production. In two experiments, American translation equivalents slowed British picture naming times, replicating the findings from Melinger (2018). In a third experiment, synonymous distractor words did not slow picture naming times, replicating the findings from Dylman and Barry (2018). A proposal couched within the Swinging Lexical Network approach is proposed to explain the discrepant findings.

Inhibition accumulates over time at multiple processing levels in bilingual language control

It is commonly assumed that bilinguals enable production in their nondominant language by inhibiting their dominant language temporarily, fully lifting inhibition to switch back. In a re-analysis of data from 416 Spanish-English bilinguals who repeatedly named a small set of pictures while switching languages in response to cues, we separated trials into different types that revealed three cumulative effects. Bilinguals named each picture (a) faster for every time they had previously named that same picture in the same language, an asymmetric repetition priming effect that was greater in their nondominant language, and (b) more slowly for every time they had previously named that same picture in the other language, an effect that was equivalent across languages and implies symmetric lateral inhibition between translation equivalents. Additionally, (c) bilinguals named pictures in the dominant language more slowly for every time they had previously named unrelated pictures in the nondominant language, exhibiting asymmetric language-wide global inhibition. These mechanisms dynamically alter the balances of activation between languages and between lemmas, providing evidence for an oft-assumed but seldom demonstrated key mechanism of bilingual control (competition between translations), resolving the mystery of why reversed language dominance sometimes emerges (the combined forces of asymmetrical effects emerge over time in mixed-language blocks), and also explaining other longer-lasting effects (block order). Key signatures of bilingual control can depend on seemingly trivial methodological details (e.g., the number of trials in a block) because inhibition is applied cumulatively at both local and global levels, persisting long after each individual act of selection.