Cumulative semantic interference is blind to morphological complexity and originates at the conceptual level.

When naming a sequence of pictures of the same semantic category (e.g., furniture), response latencies systematically increase with each named category member. This cumulative semantic interference effect has become a popular tool to investigate the cognitive architecture of language production. However, not all processes underlying the effect itself are fully understood, including the question where the effect originates from. While some researchers assume the interface of the conceptual and lexical level as its origin, others suggest the conceptual-semantic level. The latter assumption follows from the observation that cumulative effects, namely cumulative facilitation, can also be observed in purely conceptual-semantic tasks. Another unanswered question is whether cumulative interference is affected by the morphological complexity of the experimental targets. In two experiments with the same participants and the same material, we investigated both of these issues. Experiment 1, a continuous picture naming task, investigated whether morphologically complex nouns (e.g., kitchen table) elicit identical levels of cumulative interference to morphologically simple nouns (e.g., table). Our results show this to be the case, indicating that cumulative interference is unaffected by lexical information such as morphological complexity. In Experiment 2, participants classified the same target objects as either man-made or natural. As expected, we observed cumulative facilitation. A separate analysis showed that this facilitation effect can be predicted by the individuals' effect sizes of cumulative interference, suggesting a strong functional link between the two effects. Our results thus point to a conceptual-semantic origin of cumulative semantic interference.

Precision rehabilitation for aphasia by patient age, sex, aphasia severity, and time since stroke? A prespecified, systematic review-based, individual participant data, network, subgroup meta-analysis.

BACKGROUND: Stroke rehabilitation interventions are routinely personalized to address individuals' needs, goals, and challenges based on evidence from aggregated randomized controlled trials (RCT) data and meta-syntheses. Individual participant data (IPD) meta-analyses may better inform the development of precision rehabilitation approaches, quantifying treatment responses while adjusting for confounders and reducing ecological bias. AIM: We explored associations between speech and language therapy (SLT) interventions frequency (days/week), intensity (h/week), and dosage (total SLT-hours) and language outcomes for different age, sex, aphasia severity, and chronicity subgroups by undertaking prespecified subgroup network meta-analyses of the RELEASE database. METHODS: MEDLINE, EMBASE, and trial registrations were systematically searched (inception-Sept2015) for RCTs, including ⩾ 10 IPD on stroke-related aphasia. We extracted demographic, stroke, aphasia, SLT, and risk of bias data. Overall-language ability, auditory comprehension, and functional communication outcomes were standardized. A one-stage, random effects, network meta-analysis approach filtered IPD into a single optimal model, examining SLT regimen and language recovery from baseline to first post-intervention follow-up, adjusting for covariates identified a-priori. Data were dichotomized by age (⩽/> 65 years), aphasia severity (mild-moderate/ moderate-severe based on language outcomes' median value), chronicity (⩽/> 3 months), and sex subgroups. We reported estimates of means and 95% confidence intervals. Where relative variance was high (> 50%), results were reported for completeness. RESULTS: 959 IPD (25 RCTs) were analyzed. For working-age participants, greatest language gains from baseline occurred alongside moderate to high-intensity SLT (functional communication 3-to-4 h/week; overall-language and comprehension > 9 h/week); older participants' greatest gains occurred alongside low-intensity SLT (⩽ 2 h/week) except for auditory comprehension (> 9 h/week). For both age-groups, SLT-frequency and dosage associated with best language gains were similar. Participants ⩽ 3 months post-onset demonstrated greatest overall-language gains for SLT at low intensity/moderate dosage (⩽ 2 SLT-h/week; 20-to-50 h); for those > 3 months, post-stroke greatest gains were associated with moderate-intensity/high-dosage SLT (3-4 SLT-h/week; ⩾ 50 hours). For moderate-severe participants, 4 SLT-days/week conferred the greatest language gains across outcomes, with auditory comprehension gains only observed for ⩾ 4 SLT-days/week; mild-moderate participants' greatest functional communication gains were associated with similar frequency (⩾ 4 SLT-days/week) and greatest overall-language gains with higher frequency SLT (⩾ 6 days/weekly). Males' greatest gains were associated with SLT of moderate (functional communication; 3-to-4 h/weekly) or high intensity (overall-language and auditory comprehension; (> 9 h/weekly) compared to females for whom the greatest gains were associated with lower-intensity SLT (< 2 SLT-h/weekly). Consistencies across subgroups were also evident; greatest overall-language gains were associated with 20-to-50 SLT-h in total; auditory comprehension gains were generally observed when SLT > 9 h over ⩾ 4 days/week. CONCLUSIONS: We observed a treatment response in most subgroups' overall-language, auditory comprehension, and functional communication language gains. For some, the maximum treatment response varied in association with different SLT-frequency, intensity, and dosage. Where differences were observed, working-aged, chronic, mild-moderate, and male subgroups experienced their greatest language gains alongside high-frequency/intensity SLT. In contrast, older, moderate-severely impaired, and female subgroups within 3 months of aphasia onset made their greatest gains for lower-intensity SLT. The acceptability, clinical, and cost effectiveness of precision aphasia rehabilitation approaches based on age, sex, aphasia severity, and chronicity should be evaluated in future clinical RCTs.

On the lexical representation(s) of compounds: A continuous picture naming study.

The lexical representation of compound words in speech production is still under debate. While most studies with healthy adult speakers suggest that a single lemma representation is active during compound production, data from neuropsychological studies point toward multiple representations, with activation of the compound's constituent lemmas in addition to the compound's lemma. This study exploits the cumulative semantic interference effect to investigate the lexical representation of compounds in speech production. In a continuous picture naming experiment, category membership was established through the compounds' first constituents (category animals: zebra crossing, pony tail, cat litter …), while the compounds themselves were not semantically related. Moreover, pictures depicting the compounds' first constituents (zebra, pony, cat …) were presented as a control condition. As expected, naming latencies within categories increased linearly with each additionally named category member when producing monomorphemic words, which is interpreted as increasing interference during lexical selection. Importantly, this cumulative semantic interference effect was also observed for compounds. This indicates that the lemmas of the compounds' first constituents were activated during compound production, causing interference due to their semantic relationship and thereby hampering the production of the whole compound. The results are thus in line with the multiple-lemma representation account (Marelli et al., 2012). We argue that the apparent contradiction between results of previous studies with healthy adult speakers and our current study can be explained by the different experimental paradigms used. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

On the lexical representation of compound nouns: Evidence from a picture-naming task with compound targets and gender-marked determiner primes in aphasia.

Our study examines the lexical representation and processing of compounds in participants with aphasia (PWA) and language-unimpaired control speakers. Participants were engaged in primed picture-naming in German, a language that marks for grammatical gender. Gender-marked determiners served as primes (dermasc, diefem, dasneut [the]) and noun-noun compounds as targets (e.g., Goldneutfischmasc [goldfish]). Experiment 1 tested whether the compound's constituents are activated at a lexical-syntactic level during production. Primes were gender-congruent either with the morphological head of the target compound (e.g., dermasc for the target Goldneutfischmasc), or its modifier (dasneut for Goldneutfischmasc), or incongruent with both (diefem). Head congruency of prime and target produced strong facilitatory effects across groups. Modifier congruent primes produced contrasting effects. Modifier congruency speeded up picture naming in the controls and PWA with isolated deficits of lexical access (PWA-lex) but they delayed picture naming in PWA with additional deficits of phonological encoding (PWA-pho). Both patterns suggest that the lemmas of both constituents of compound targets and their grammatical gender are activated during compound retrieval, in line with a multiple-lemma representation of compounds. Experiment 2 explored the nature of the observed effects compared to a gender-neutral control condition. While facilitatory effects were shown by PWA-lex and the controls, PWA-pho did not profit from congruent primes but showed inhibitory effects by incongruent primes, exclusively. Inhibitory effects were also attested for the controls but not for PWA-lex. The functional origin of determiner priming effects and their theoretical and clinical implications are discussed in the framework of current accounts.

Morphological facilitation and semantic interference in compound production: An ERP study.

This study investigates the production of nominal compounds (Experiment 1) and simple nouns (Experiment 2) in a picture-word interference (PWI) paradigm to test models of morpho-lexical representation and processing. The continuous electroencephalogram (EEG) was registered and event-related brain potentials [ERPs] were analyzed in addition to picture-naming latencies. Experiment 1 used morphologically and semantically related distractor words to tap into different pre-articulatory planning stages during compound production. Relative to unrelated distractors, naming was speeded when distractors corresponded to morphemes of the compound (sun or flower for the target sunflower), but slowed when distractors were from the same semantic category as the compound (tulip ➔ sunflower). Distractors from the same category as the compound's first constituent (moon ➔ sunflower) had no influence. The diverging effects for semantic and morphological distractors replicate results from earlier studies. ERPs revealed different effects of morphological and semantic distractors with an interesting time course: morphological effects had an earlier onset. Comparable to the naming latencies, no ERP effects were obtained for distractors from the same semantic category as the compound's first constituent. Experiment 2 investigated the effectiveness of the latter distractors, presenting them with pictures of the compounds' first constituents (e.g., moon ➔ sun). Interference was confirmed both behaviorally and in the ERPs, showing that the absence of an effect in Experiment 1 was not due to the materials used. Considering current models of speech production, the data are best explained by a cascading flow of activation throughout semantic, lexical and morpho-phonological steps of speech planning.

RELEASE: a protocol for a systematic review based, individual participant data, meta- and network meta-analysis, of complex speech-language therapy interventions for stroke-related aphasia.

Background: Speech and language therapy (SLT) benefits people with aphasia following stroke. Group level summary statistics from randomised controlled trials hinder exploration of highly complex SLT interventions and a clinically relevant heterogeneous population. Creating a database of individual participant data (IPD) for people with aphasia aims to allow exploration of individual and therapy-related predictors of recovery and prognosis. Aim: To explore the contribution that individual participant characteristics (including stroke and aphasia profiles) and SLT intervention components make to language recovery following stroke. Methods and procedures: We will identify eligible IPD datasets (including randomised controlled trials, non-randomised comparison studies, observational studies and registries) and invite their contribution to the database. Where possible, we will use meta- and network meta-analysis to explore language performance after stroke and predictors of recovery as it relates to participants who had no SLT, historical SLT or SLT in the primary research study. We will also examine the components of effective SLT interventions. Outcomes and results: Outcomes include changes in measures of functional communication, overall severity of language impairment, auditory comprehension, spoken language (including naming), reading and writing from baseline. Data captured on assessment tools will be collated and transformed to a standardised measure for each of the outcome domains. Conclusion: Our planned systematic-review-based IPD meta- and network meta-analysis is a large scale, international, multidisciplinary and methodologically complex endeavour. It will enable hypotheses to be generated and tested to optimise and inform development of interventions for people with aphasia after stroke. Systematic review registration: The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO; registration number: CRD42018110947).

Age-related effects in compound production: Evidence from a double-object picture naming task.

This study investigated effects of healthy ageing and of non-verbal attentional control on speech production. Young and older speakers participated in a picture-word interference (PWI) task with compound targets. To increase the processing load, the two pictures of the compounds' constituents were presented side-by-side for spoken naming (e.g., a picture of a sun + a picture of a flower to be named with sunflower). Written distractors either corresponded to the first or second constituent (sun or flower → sunflower), or were semantically related either to the first constituent of the target (moon → sunflower) or to the second constituent/whole word (tulip → sunflower). Morpho-phonological facilitation was obtained for both constituents, whereas semantic interference was restricted to first-constituent-related semantic distractors. Furthermore, a trend towards facilitation was obtained for distractors that were semantically related to the whole word. Older speakers were slower and produced more errors than young speakers. While morphological effects of first-constituent distractors were stronger for the elderly, the semantic effects were not affected by age. Non-verbal attentional control processes, measured in the Simon task, significantly contributed to morpho-phonological priming in the elderly, but they did not affect semantic interference or semantic facilitation. With a picture naming task that increases the semantic and lexical processing load, we corroborate earlier evidence that word-finding difficulties in the elderly result from deficient phonological encoding, whereas lexical-semantic and morpho-phonological representations remain stable with age.

Age-related effects in compound production: Intact lexical representations but more effortful encoding.

The production of nominal compounds in the presence of morphological, semantic, and unrelated distractor words (picture-word interference paradigm) was investigated in young (M = 27 years) and older (M = 70.5 years) German speakers to test models of speech production and lexical representation. Constituent distractors of compound targets (lip or stick for the target LIPSTICK) speeded compound naming, while naming was slowed by distractors that were categorically related to the compound as a whole (powder → LIPSTICK). Furthermore, no effects were obtained for distractors from the same category as the first constituent of compound targets in picture-naming latencies (toe → LIPSTICK). These effects were present in both age groups and indicate that compounds are stored holistically at the lemma level, and as morphemes at the word-form level, unaffected by age. Main effects of age revealed overall slower picture naming and less accurate responses in the elderly. Furthermore, older speakers showed stronger morphological facilitation, while semantic distractor effects were unaffected by age. In a non-verbal attentional control task (Simon task), older speakers were slower overall and showed larger processing costs than young speakers in the conflict (incongruent) condition. Our data replicate a decline in non-verbal attentional control with age and also reveal slower and more error-prone picture-naming in the elderly. These language-specific changes, however, seem to be independent from attentional control and are likely to result from less fluent morpho-phonological encoding in the elderly.

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.

Grammatical-gender effects in noun-noun compound production: Evidence from German.

We examined how noun-noun compounds and their syntactic properties are lexically stored and processed in speech production. Using gender-marked determiner primes ( dermasc, diefem, dasneut [the]) in a picture naming task, we tested for specific effects from determiners congruent with either the modifier or the head of the compound target (e.g., Teemasckannefem [teapot]) to examine whether the constituents are processed independently at the syntactic level. Experiment 1 assessed effects of auditory gender-marked determiner primes in bare noun picture naming, and Experiment 2 assessed effects of visual gender-marked determiner primes in determiner-noun picture naming. Three prime conditions were implemented: (a) head-congruent determiner (e.g., diefem), (b) modifier-congruent determiner (e.g., dermasc), and (c) incongruent determiner (e.g., dasneuter). We observed a facilitation effect of head congruency but no effect of modifier congruency. In Experiment 3, participants produced novel noun-noun compounds in response to two pictures, demanding independent processing of head and modifier at the syntactic level. Now, head and modifier congruency effects were obtained, demonstrating the general sensitivity of our task. Our data support the notion of a single-lemma representation of lexically stored compound nouns in the German production lexicon.

Semantically Transparent and Opaque Compounds in German Noun-Phrase Production: Evidence for Morphemes in Speaking.

This study examines the lexical representation and processing of noun-noun compounds and their grammatical gender during speech production in German, a language that codes for grammatical gender (masculine, feminine, and neuter). Using a picture-word interference paradigm, participants produced determiner-compound noun phrases in response to pictures, while ignoring written distractor words. Compound targets were either semantically transparent (e.g., birdhouse) or opaque (e.g., hotdog), and their constituent nouns either had the same or a different gender (internal gender match). Effects of gender-congruent but otherwise unrelated distractor nouns, and of two morphologically related distractors corresponding to the first or second constituent were assessed relative to a completely unrelated, gender-incongruent distractor baseline. Both constituent distractors strongly facilitated compound naming, and these effects were independent of the targets' semantic transparency. This supports retrieval of constituent morphemes for semantically transparent and opaque compounds during speech production. Furthermore, gender congruency between compounds and distractors did not speed up naming in general, but interacted with gender match of the compounds' constituent nouns, and their semantic transparency. A significant gender-congruency effect was obtained with semantically transparent compounds, consisting of two constituent nouns of the same gender, only. In principle, this pattern is compatible with a multiple lemma representation account for semantically transparent, but not for opaque compounds. The data also fit with a more parsimonious, holistic representation for all compounds at the lemma level, when differences in co-activation patterns for semantically transparent and opaque compounds are considered.

Processing of nominal compounds and gender-marked determiners in aphasia: evidence from German.

The present study tests theories about the representation of compound nouns and grammatical gender in the mental lexicon. Comprehension and production of determiner-compound-noun phrases were examined in three aphasic native speakers of German, a language that marks grammatical gender on definite determiners of nouns. In picture naming, participants were more impaired in retrieving compounds than matched simple nouns and showed different error patterns. However, retrieving the correct determiner was equally impaired for compounds and simple nouns. Clear dissociations between impaired determiner retrieval in production and relatively preserved processing of determiner-noun phrases in comprehension were observed for existing compounds and simple nouns. In contrast, processing of novel compounds was more impaired in both modalities, and gender-mismatch effects were especially observed for novel compounds. The results support the account of decomposed word forms and holistic lemma representations of compound nouns in the mental lexicon.

Increased red cell corpuscular volume and hepatic mitochondrial function in NRTI-treated HIV infected patients.

An increase of the mean corpuscular volume of the red blood cells has been repeatedly described in antiretroviral treated patients. Most commonly macrocytosis was associated with the use of certain nucleoside reverse transcriptase inhibitors. The aim of this study was to analyse if macrocytosis might be a marker of mitochondrial toxicity in antiretrovirally treated HIV-infected patients. Using the (13)C-methionine breath test we analysed the hepatic mitochondrial function in vivo in antiretrovirally treated HIV-infected patients with macrocytosis. MCV was significantly negatively correlated to the breath test results. For the first time we could show a significant association between an increase of the mean corpuscular erythrocyte volume by treatment with nucleoside reverse transcriptase inhibitors (NRTI) and the hepatic mitochondrial function in vivo.

Unambiguous generalization effects after treatment of non-canonical sentence production in German agrammatism.

Agrammatism is-among others, characterized by a deficit in producing grammatical structures. Of specific difficulty is the utilization of complex, non-canonical sentence structures (e.g. object-questions, passives, object-clefts). Several studies have documented positive effects when applying a specific treatment protocol in terms of increasingly correct production of target complex sentence structures with some variance in generalization patterns noted across individuals. The objective of this intervention study was to evaluate an intervention program focussing on the production of non-canonical sentences. Hypotheses about the occurrence of treatment effects were formulated on the basis of syntactic complexity, referring to the amount of syntactic phrase structures necessary to generate specific German sentence structures. A multiple single case study with seven agrammatic participants was applied, each participant receiving training in the production of object-relative-clauses and who-questions. The investigation was designed to unambiguously evaluate for each individual, structure specific and generalized learning effects with respect to the production of object-relative-clauses, who-questions and passive sentences. Results showed significant improvements for all sentences types. This outcome is considered within methodological issues of treatment studies. Theoretical and clinical implications are discussed.

A cross-linguistic data bank for oral picture naming in Dutch, English, German, French, Italian, Russian, Spanish, and Swedish (PEDOI).

The well established effect of word frequency on adult's picture naming performance is now called into question. This is particularly true for variables which are correlated with frequency, as is the case of age of word acquisition. Since the work of [Carrol and White, 1973] there is growing agreement among researchers to confer an important role in lexical access to this variable. Indeed, it has been shown ( [Hodgson and Ellis, 1998]) that for normal English-speaking adults only the variables 'age-of-acquisition' and 'name agreement' are independent predictors of naming success among the various variables considered. However, when brain-damaged subjects with and without degenerative pathologies are studied, word frequency and word length as well as concept familiarity all give significant effects ( [Hirsh and Funnell, 1995]; [Lambon Ralph et al., 1998]; [Nickels and Howard, 1995]). Finally, it has been suggested that the production of specific error types may be related to such variables. According to [Nickels and Howard, 1994] the production of semantic errors is specifically affected by 'imageability' and in the recent study by [Kremin et al., 2001] 'age of acquisition' predicts (frank) word finding difficulties.