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Models of visual word recognition differ as to how print exposure modulates orthographic precision. In some models, precision is the optimal end state of a lexical representation; the associations between letters and positions are initially approximate and become more precise as readers gain exposure to the word. In others, flexible orthographic coding that allows for rapid access to semantics (i.e., 'good enough' orthographic processing) is the optimal end state. To adjudicate between these trajectories, we compared the size of transposed-letter ERP priming effects on two ERP components thought to reflect orthographic and lexico-semantic processing across languages in late English-Spanish bilinguals. Words that are represented precisely should be less susceptible to activation by transposed-letter primes (e.g., shpae-SHAPE) than words that are not, and should therefore yield smaller priming effects. Overall, targets elicited smaller N250s and N400s and faster responses when preceded by transposed-letter primes compared to substitution primes (e.g., shgue-SHAPE). The only effect that significantly differed between languages was N400 priming, which was larger in English, the dominant language. We suggest that these results favor models of learning to read according to which 'good enough' orthographic processing increases with print exposure. [ABSTRACT FROM AUTHOR]

The picture word interference (PWI) paradigm and ERPs were used to investigate whether lexical selection in deaf and hearing ASL-English bilinguals occurs via lexical competition or whether the response exclusion hypothesis (REH) for PWI effects is supported. The REH predicts that semantic interference should not occur for bimodal bilinguals because sign and word responses do not compete within an output buffer. Bimodal bilinguals named pictures in ASL, preceded by either a translation equivalent, semantically-related, or unrelated English written word. In both the translation and semantically-related conditions bimodal bilinguals showed facilitation effects: reduced RTs and N400 amplitudes for related compared to unrelated prime conditions. We also observed an unexpected focal left anterior positivity that was stronger in the translation condition, which we speculate may be due to articulatory priming. Overall, the results support the REH and models of bilingual language production that assume lexical selection occurs without competition between languages. [ABSTRACT FROM AUTHOR]

Increasing the neighbourhood density of a word typically facilitates lexical decision responses and interferes in sentence reading. The Multiple Read-Out Model accounts for such variation by postulating that word responses in the lexical decision task can be made via two mechanisms – identifying the word or using the global lexical activity that it generates. Here, we asked whether adding unrelated flanking words to either side of the target would modulate the relative contribution of these two mechanisms. That is, do flankers promote the use of word identification processes that are more characteristic of sentence reading? In line with our hypothesis, in Experiment 1 flanker words increased the inhibitory influence of orthographic neighbours relative to single word presentation. In Experiment 2, flanker neighbourhood density did not affect lexical decisions to central targets. This pattern indicates that the mechanisms used to make a lexical decision can be modulated by a minimal "sentence-like" context. [ABSTRACT FROM AUTHOR]

Background: The semantic fluency task involves naming as many items as possible in a given category (e.g., animals) in one minute. It is often interpreted as a measure of word retrieval, but also draws on executive function abilities to organize responses and develop task‐specific strategies. Indeed, both language skills and dementia severity ratings have recently been found to correlate with semantic fluency performance in patients with primary progressive aphasia (Riello et al., 2022; Scheffel et al., 2021). Here, we focused instead on how performance on language and executive function measures predicts longitudinal change in semantic fluency performance in patients with progressive agrammatic aphasia and/or apraxia of speech (AOS). Method: Patients with isolated agrammatic aphasia (n = 10), isolated AOS (n = 42), or a combination of the two (n = 59) with 1‐7 visits (mean = 2.19) were included. We used Bayesian hierarchical linear models to investigate whether baseline measures of executive function or language were associated with the rate at which semantic fluency performance changes over time while accounting for baseline diagnosis group, sex, education, age at baseline, and baseline disease duration. Result: Semantic fluency performance declined over time, at a similar rate irrespective of diagnostic group (isolated or combined aphasia or AOS; Figure 1). Across all patients, higher executive function abilities at baseline, as indicated by faster Trails Making Test B completion times, predicted higher baseline semantic fluency performance and also a steeper annual rate of decline (Figure 2). Similarly, higher fluency ratings during the Western Aphasia Battery‐Revised picture description at baseline were associated with higher baseline semantic fluency performance and faster decline. Baseline performance on the Boston Naming Test and Token Test were also associated with baseline semantic fluency, but not with longitudinal change. Conclusion: These results better delineate how language and executive function abilities support performance in the semantic fluency task. Higher abilities in those areas at baseline do not appear to be protective over time. Rather, the differences in semantic fluency that are present at baseline disappear as the disease progresses. [ABSTRACT FROM AUTHOR]

In an investigation of the development of fine-tuning for word processing across the late elementary school years as indexed by the posterior N1 and P2 components of the ERP waveform, third, fourth, and fifth graders and a comparison group of adults viewed words, pseudowords, nonpronounceable letter strings, and false font strings in a semantic categorization task. In adults, N1 was larger to and P2 was later to words as compared to pseudowords, a finely tuned effect of lexicality reflecting specialization for word processing. In contrast, in each group of children, N1 was larger to letter strings than false font strings and P2 was larger to false font strings than letter strings, reflecting coarse encoding for orthography. In regression analyses, scores on standardized behavioral test measures of orthographic knowledge, decoding skill, and fluency predicted N1 amplitude; these effects were not significant with age included as a separate predictor. None of the behavioral scores, in models including or not including age, predicted P2 amplitude. In direct comparisons between groups, there were multiple differences between the child and adult groups for both N1 and P2 amplitude effects, and only a single significant difference between two child groups. Overall, the findings suggest a lengthy developmental time course for the fine-tuning of early word processing as indexed by N1 and P2. [ABSTRACT FROM AUTHOR]

One of the cool aspects of the original implementation of the BIA model (van Heuven, Dijkstra & Grainger, 1998) was the discovery that inhibitory connections between language nodes and lexical representations was a necessary feature for the model to be able to simulate the target data set at that time. This demonstrates the importance of computational modeling, a key point of the present target article, since inhibitory connections were postulated to occur only between representations at the same level in the conceptual model (Grainger & Dijkstra, 1992). Top-down inhibition was subsequently dropped in the BIA+ model (Dijkstra & van Heuven, 2002), and the Multilink model of the present target article (Dijkstra, Wahl, Buytenhuijs, van Halem, Al-jibouri, de Korte & Rekké, 2018) goes one step further by removing all kinds of inhibitory connections, both between and within levels. Instead, the authors of the model propose that bilingual language processing relies on bidirectional excitatory connections between representations at different levels. This is curious given that even more evidence has accumulated in favor of inhibition since the original implementation of the BIA model, both between neighboring lexical representations (i.e., lateral inhibition) and from language membership representations (e.g., language nodes and tags) down to lexical representations. In this commentary, we focus on whether the exclusion of these two inhibitory processes is warranted, and how the inclusion of these processes might benefit future developments of the model. [ABSTRACT FROM AUTHOR]

Background and Objectives: Nonverbal oral apraxia (NVOA) is the inability to plan, sequence, and execute voluntary oromotor movements in the absence of weakness. In the context of neurodegenerative disease, it remains unclear whether it is linked to a specific underlying pathologic, clinical, or neuroimaging finding. Thus, we aimed to assess the clinicopathologic and neuroimaging associations of NVOA., Methods: We conducted a retrospective study of autopsy-confirmed patients previously assessed through an NVOA evaluation tool with a previously published cutpoint to screen for NVOA. We compared demographic and clinical characteristics and postmortem pathology between those who developed NVOA and those who did not. We also compared clinicopathologic characteristics in mild vs greater than mild NVOA and early vs late-emerging NVOA. SPM12 was used to assess patterns of gray matter loss in NVOA vs non-NVOA with age and sex included as covariates., Results: A total of 104 patients (median age at symptom onset 63 years, 43% female) were included in the study. 63 (60.6%) developed NVOA. NVOA appeared at a median of 4.3 years from symptom onset. 29% developed NVOA within the first 3 years. Primary progressive apraxia of speech and the nonfluent variant of primary progressive aphasia were the most common baseline diagnoses in the NVOA group while progressive supranuclear palsy (PSP) syndrome and logopenic progressive aphasia (LPA) were the most common in patients without NVOA. Atrophy of the left lateral and medial posterior frontal cortex was related to NVOA. The most common pathologies associated with NVOA were PSP (36.5%) and corticobasal degeneration (CBD) (33.3%). In patients without NVOA, PSP (26.8%) and other pathologies (26.8%) were the most frequent. 11% of patients with NVOA had persistently mild NVOA and were more likely to have baseline diagnoses of LPA, PSP syndrome, or semantic dementia. The most frequent pathologies in this group were Alzheimer disease and PSP. The pathologic associations of greater than mild NVOA were CBD and PSP., Discussion: NVOA is present in several clinical syndromes. It is most associated with PSP and CBD. NVOA is a manifestation of left lateral and medial posterior frontal cortex damage rather than a particular pathology.