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It is well-established from fMRI experiments employing gradient echo echo-planar imaging (EPI) sequences that overt speech production introduces signal artefacts compromising accurate detection of task-related responses. Both design and post-processing (denoising) techniques have been proposed and implemented over the years to mitigate the various noise sources. Recently, fMRI studies of speech production have begun to adopt multiband EPI sequences that offer better signal-to-noise ratio (SNR) and temporal resolution allowing adequate sampling of physiological noise sources (e.g., respiration, cardiovascular effects) and reduced scanner acoustic noise. However, these new sequences may also introduce additional noise sources. In this study, we demonstrate the impact of applying several noise-estimation and removal approaches to continuous multiband fMRI data acquired during a naming-to-definition task, including rigid body motion regression and outlier censoring, principal component analysis for removal of cerebrospinal fluid (CSF)/edge-related noise components, and global fMRI signal regression (using two different approaches) compared to a baseline of realignment and unwarping alone. Our results show the strongest and most spatially extensive sources of physiological noise are the global signal fluctuations arising from respiration and muscle action and CSF/edge-related noise components, with residual rigid body motion contributing relatively little variance. Interestingly, denoising approaches tended to reduce and enhance task-related BOLD signal increases and decreases, respectively. Global signal regression using a voxel-wise linear model of the global signal estimated from unmasked data resulted in dramatic improvements in temporal SNR. Overall, these findings show the benefits of combining continuous multiband EPI sequences and denoising approaches to investigate the neurobiology of speech production.

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The purpose of the current study was to extend the research on the possible role of verbal mediation in the establishment of comparative relations. We conducted four experiments in which 14 participants received conditional discrimination training with nonarbitrary and arbitrary stimuli, followed by derived comparative and transformation of function tests. Participants learned to select the smallest or biggest comparison across multiple exemplars in the presence of abstract samples. Next, participants learned to select arbitrary comparisons in the presence of contextual cues to establish a size ranking among comparisons. To assess verbal mediation during mutual and combinatorial entailment tests, participants were instructed to talk out loud. When they failed to perform correctly during derived relations tests, participants were trained to tact and intraverbally relate stimuli. The results suggest that relational training alone was not sufficient to establish comparative relations and that adult participants engaged in problem solving consistent with intraverbal bidirectional naming during emergent relations tests.

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Anomia is a common consequence following brain damage and a central symptom in semantic dementia (SD) and post-stroke aphasia (PSA), for instance. Picture naming tests are often used in clinical assessments and experience suggests that items vary systematically in their difficulty. Despite clinical intuitions and theoretical accounts, however, the existence and determinants of such a naming difficulty gradient remain to be empirically established and evaluated. Seizing the unique opportunity of two large-scale datasets of semantic dementia and post-stroke aphasia patients assessed with the same picture naming test, we applied an Item Response Theory (IRT) approach and we (a) established that an item naming difficulty gradient exists, which (b) partly differs between patient groups, and is (c) related in part to a limited number of psycholinguistic properties - frequency and familiarity for SD, frequency and word length for PSA. Our findings offer exciting future avenues for new, adaptive, time-efficient, and patient-tailored approaches to naming assessment and therapy.

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Name agreement (NA) refers to the degree to which speakers agree on a picture's name. A robust finding is that speakers are faster to name pictures with high agreement (HA) than those with low agreement (LA). This NA effect is thought to occur because LA pictures strongly activate several names, so speakers need time to select one. HA pictures, in contrast, strongly activate a single name, so there is no need to select one name out of several alternatives. Recent models of lexical access suggest that the structure of the mental lexicon changes with experience. Thus, speakers should consider a range of names when naming LA pictures, but the extent to which they consider each of these names should change with experience. We tested these hypotheses in two picture-naming experiments. In Experiment 1, participants were faster to name LA than HA pictures when they named each picture once. Importantly, they were faster to produce modal names (provided by most participants) than alternative names for LA pictures, consistent with the view that speakers activate multiple names for LA pictures. In Experiment 2, participants were familiarised with the modal name before the experiment and named each picture three times. Although there was still an NA effect when participants named the pictures the first time, it was reduced in comparison to Experiment 1 and was further reduced with each picture repetition. Thus, familiarisation and repetition reduced the NA effect but did not eliminate it, suggesting speakers activate a range of plausible names.

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Van den Hoven et al. contested my interpretation of Wernicke regarding the role of the arcuate fasciculus (AF) in word production. Here, I clarify and defend my interpretation. They also questioned the assumption of AF subtracts in my modern account, stating that subtracts are difficult to distinguish anatomically due to overlapping terminations. Here, I make clear that overlap in terminations was actually part of my account, in which differentially damaged subtracts explained patients' differential naming and repetition performance as well as types of repetition performance.

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Visual imagining has been proposed to play a role in the emergence of derived stimulus relations. We examined whether test-relevant visual imagining during baseline training would, accordingly, facilitate emergent visual-visual conditional discriminations at test. Adult participants (n = 75) were randomly assigned to three groups. Baseline tact training established conditional discriminations among sets of image samples and textual comparisons (AC/BD), and baseline intraverbal training established conditional discriminations among pairs of textual stimuli (CD). Two groups received tact before intraverbal training, and one group received the reverse sequence. During intraverbal training, one of the former groups was instructed to visualize the images that went with the textual stimuli. These instructions did not affect participants' retrospective self-reports of test-relevant visual imagining during training. Nevertheless, they produced a large effect on correct responding in an image-matching test (AB/BA) that followed intraverbal training. This effect was independent of baseline retention.

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BACKGROUND: Linguistic deficits are common across neurological and neurodegenerative disorders. Currently there are limited neuropsychological norms available for Spanish-speaking adults residing in the U.S. OBJECTIVE: To generate norms for two verbal fluency tests and the Boston Naming Test (BNT) in a Spanish-speaking population in the U.S., with adjustments for demographic and cultural variables. METHODS: The sample consisted of 245 adults from the U.S. Participants completed phonological and semantic verbal fluency tests and the BNT. A standardized two-step statistical procedure was used. RESULTS: For the phoneme F, interactions between Spanish proficiency, age, and education arose. Better performance on phonemes A, S, and M was related to education. Spanish proficiency, acculturation, and time in the U.S. were associated with the phonemes S, A, P, M, and R. An age by education interaction was found for phonemes M and R. The FAS and PMR triads were related to age, sex, time in U.S., and Spanish proficiency. For the semantic verbal fluency tests, an interaction between education and Spanish proficiency arose. For the BNT, test scores were related to education, and significant interactions were also found based on education's interaction with Spanish proficiency and acculturation. CONCLUSION: This study highlights the importance of accounting for sociodemographic and acculturative factors when developing normative data for verbal fluency tests and the BNT for dominant Spanish-speaking adults in the U.S. These sociodemographically-adjusted norms will help improve accuracy of diagnosis and interpretation of linguistic test performance in Spanish speakers living in the U.S.

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INTRODUCTION AND OBJECTIVES: Although the Psychometric Hepatic Encephalopathy Score (PHES) remains the gold standard in diagnosing minimal hepatic encephalopathy (MHE), its complexity limits its application in clinical practice. While more convenient tests, such as the Stroop test, Quickstroop, and the 1-min animal naming test (ANT-1), have emerged, they haven't been validated in our setting. Our objective was to validate these tests in our population. PATIENTS AND METHODS: This multicenter, observational, descriptive, and cross-sectional study was conducted in three hospitals in northeastern Mexico. MHE was defined as a PHES <-4. We included patients with cirrhosis aged >15 years without a history of overt hepatic encephalopathy. Data regarding sex, age, education, Child-Pugh/MELD-Na scores, etiology of cirrhosis, diabetes, hypertension, obesity, ascites, and clinically significant portal hypertension was collected. Fisher's exact test, Mann-Whitney U test, and receiver operating characteristic (ROC) curves were used for statistical analysis. RESULTS: Of the 121 patients included, 35.5 % were diagnosed with MHE. The presence of MHE was significantly associated with education level, years of study, and scores in the Stroop test, Quickstroop, and ANT-1. The AUROC curves were 77.9 %, 74.6 %, and 72.7 % for the Stroop test, Quickstroop, and ANT-1, respectively. The resulting cut-off points were 218.398 (sensitivity: 74 %; specificity: 74 %), 40.535 (sensitivity: 77 %; specificity: 68 %), and <16 animals (sensitivity: 58 %; specificity: 79 %), respectively. CONCLUSIONS: These tests are valid diagnostic tools for detecting MHE in our population. Their simpler use and applicability could increase the early diagnosis of MHE and prompt primary prophylaxis initiation for overt hepatic encephalopathy.

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Reading fluency, the ability to read quickly and accurately, is a critical marker of successful reading and is notoriously difficult to improve in reading disabled populations. Despite its importance to functional literacy, fluency is a relatively under-studied aspect of reading, and the neural correlates of reading fluency are not well understood. Here, we review the literature of the neural correlates of reading fluency as well as rapid automatized naming (RAN), a task that is robustly related to reading fluency. In a qualitative review of the neuroimaging literature, we evaluated structural and functional MRI studies of reading fluency in readers from a range of skill levels. This was followed by a quantitative activation likelihood estimate (ALE) meta-analysis of fMRI studies of reading speed and RAN measures. We anticipated that reading speed, relative to untimed reading and reading-related tasks, would harness ventral reading pathways that are thought to enable the fast, visual recognition of words. The qualitative review showed that speeded reading taps the entire canonical reading network. The meta-analysis indicated a stronger role of the ventral reading pathway in rapid reading and rapid naming. Both reviews identified regions outside the canonical reading network that contribute to reading fluency, such as the bilateral insula and superior parietal lobule. We suggest that fluent reading engages both domain-specific reading pathways as well as domain-general regions that support overall task performance and discuss future avenues of research to expand our understanding of the neural bases of fluent reading.

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Object recognition and visual categorization are typically swift and seemingly effortless tasks that involve numerous underlying processes. In our investigation, we utilized a picture naming task to explore the processing of rarely encountered objects (visual hapaxes) in comparison to common objects. Our aim was to determine the stage at which these rare objects are classified as unnamable. Contrary to our expectations and in contrast to some prior research on event-related potentials (ERPs) with novel and atypical objects, no differences between conditions were observed in the late time windows corresponding to the P300 or N400 components. However, distinctive patterns between hapaxes and common objects surfaced in three early time windows, corresponding to the posterior N1 and P2 waves, as well as a widespread N2 wave. According to the ERP data, the differentiation between hapaxes and common objects occurs within the first 380 ms of the processing line, involving only limited and indirect top-down influence.

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Theories of bilingual language production predict that bilinguals with Alzheimer's disease (AD) should exhibit one of two decline patterns. Either parallel decline of both languages (if decline reflects damage to semantic representations that are accessed by both languages), or asymmetrical decline, with greater decline of the nondominant language (if decline reflects reduced ability to resolve competition from the dominant language with disease progression). Only two previous studies examined decline longitudinally with one showing parallel, and the other asymmetrical, decline. We examined decline over 2-7 years (3.9 on average) in Spanish-English bilinguals (N = 23). Logistic regression revealed a parallel decline pattern at one year from baseline, but an asymmetrical decline pattern over the longer decline period, with greater decline of the nondominant language (when calculating predicted probabilities of a correct response). The asymmetrical decline pattern was significantly greater for the nondominant language only when including item-difficulty in the model. Exploratory analyses across dominance groups looking at proportional decline relative to initial naming accuracy further suggested that decline of the nondominant language may be more precipitous if that language was acquired later in life, but the critical interaction needed to support this possibility was not statistically significant in a logistic regression analysis. These results suggest that accessibility of the nondominant language may initially be more resilient in early versus more advanced AD, and that AD affects shared semantic representations before executive control declines to a point where the ability to name pictures in single-language testing block is disrupted. Additional work is needed to determine if asymmetrical decline patterns are magnified by late age of acquisition of the nondominant language, and if more subtle impairments to executive control underlie impairments to language switching that occur in the earliest stages of AD (even preclinically).

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Anomia, characterized by difficulty in word retrieval, particularly action verbs, poses a significant challenge in post-stroke aphasia. Repetitive transcranial magnetic stimulation (rTMS) has gained attention for language processing investigations and interventions. This systematic review explores the potential of rTMS as a modality to address action-verb deficits in post-stroke aphasia. We searched MEDLINE via PubMed, CINAHL via Ebsco and Web of Science in February 2024 for English articles (1996-2024). Eligible studies involved post-stroke aphasia action naming rehabilitation with rTMS. In some of these studies, rTMS was combined with speech-language therapy. In total, 10 studies were included in this systematic review. These articles highlight the potential of rTMS in improving verb retrieval deficits. While significant improvements may not be evident, notable progress both before and after intervention is observed in this review. However, it also underscores the need for further research to enhance language recovery for individuals with post-stroke aphasia.

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BACKGROUND: Few investigations examined the relationship between microstructural white matter integrity and subacute post-stroke linguistic performance or the relationship between microstructural integrity and the recovery of language function. We examined two key questions: (1) How does subacute language performance, measured in single words and discourse, relate to the microstructural integrity of key white matter regions of interest in the language network? and (2) Does the integrity of these regions before treatment predict the improvement or resolution of linguistic symptoms immediately and chronically following treatment? METHODS: 58 participants within the first three months of stroke were enrolled in a randomized, single-center, double-blind, sham-controlled, study of anodal transcranial direct current stimulation combined with a computer-delivered speech and language naming therapy for subacute aphasia and were asked to complete magnetic resonance imaging at enrollment. Microstructural integrity was evaluated using diffusion tensor imaging processed with atlas-based segmentation. Regression and correlation analyses were conducted. RESULTS: A subset of 22 participants received diffusion tensor imaging. Picture naming accuracy significantly correlated with lower mean diffusivity (higher microstructural integrity) in the left posterior inferior temporal gyrus. Recovery of naming performance was predicted by days since stroke and baseline microstructural integrity of the left posterior middle temporal gyrus, arcuate fasciculus, and superior longitudinal fasciculus. Recovery of discourse efficiency was significantly predicted by the same model. CONCLUSIONS: This study demonstrates an association between picture naming and discourse and microstructural integrity of the key regions in the language network for patients with subacute post-stroke aphasia. Baseline microstructural integrity significantly predicts language recovery.

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Background: All common variants of primary progressive aphasia (PPA) exhibit naming deficits. Variants are distinguished by relative deficits in repetition (logopenic; lvPPA), object knowledge (semantic; svPPA), and agrammatism or articulation (non-fluent/agrammatic; nfavPPA; Gorno-Tempini et al., 2011). The Hopkins Action Naming Assessment (HANA) is a 30-item verb naming task that can distinguish between variants (Stockbridge et al., 2021). Item-level accuracy is driven by target verb frequency, semantic information density, and conceptual concreteness of the target word (Stockbridge, Venezia, et al., 2022). Aims: In this investigation, we examined whether word frequency, semantic density, concreteness, and age of acquisition (AoA) also shaped the incorrect responses patients provided. We hypothesised that error responses would vary in these dimensions as a function of PPA variant. Methods & Procedures: The HANA was administered to 271 participants with PPA, resulting in 443 total administrations and 4,529 analysable error responses. Standardised differences between error and target responses for frequency, density, concreteness, and AoA were calculated and averaged for each patient. Analysis of variance (ANOVA) for correlated samples was used to compare variants and planned post-hoc analyses examined the effect of variant on each response quality. Outcomes & Results: Participants were similar in age, sex, handedness, and education. There was a significant interaction between PPA variant and the standardised mean differences in lexical qualities (Pillai's Trace=0.11, F(9, 747)=3.19, p<0.001). Univariate ANOVAs revealed significant differences in the semantic density of error responses relative to the target (F(3)=7.91, p<0.001, ηP 2=0.09), as individuals with lvPPA tended to produce error responses with greater semantic density than the target when compared to the words produced by individuals with nfavPPA (mean difference=1.45, 95%CI=[0.60,2.29], p<0.001; Figure 1). PPA variants also differed in the concreteness of their error responses relative to the target (F(3)=5.99, p<0.001, ηP 2=0.07), as error responses produced by individuals with nfavPPA were significantly more concrete than those with lvPPA (mean difference=0.08, 95%CI=[0.02,0.13], p=0.003) or svPPA (mean difference=0.08, 95%CI=[0.02,0.14], p=0.007). Variants did not differ significantly in AoA or frequency of responses relative to their targets. All variants tended to produce more frequent words with a lower AoA than the target verb. Conclusions: Error responses tended to be more semantically dense, more concrete, higher frequency, and younger AoA than the target verb. However, PPA variants differed significantly in the extent to which these broader trends held true. These distinct patterns may be included as part of a larger diagnostic picture that to distinguish among PPA variants.

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The exploration of naming error patterns in aphasia provides insights into the cognitive processes underlying naming performance. We investigated how semantic and phonological abilities correlate and how they influence naming performance in aphasia. Data from 296 individuals with aphasia, drawn from the Moss Aphasia Psycholinguistics Project Database, were analyzed using a structural equation model. The model incorporated latent variables for semantics and phonology and manifest variables for naming accuracy and error patterns. There was a moderate positive correlation between semantics and phonology after controlling for overall aphasia severity. Both semantic and phonological abilities influenced naming accuracy. Semantic abilities negatively related to semantic, mixed, unrelated errors, and no responses. Interestingly, phonology positively affected semantic errors. Additionally, phonological abilities negatively related to each of phonological and neologism errors. These results highlight the role of semantic and phonological skills on naming performance in aphasia and reveal a relationship between these cognitive processes.

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Introduction: Psychotic disorders have been associated with dysregulated stress reactions and adaptation. Little is known about the neuroendocrine responses to psychosocial stress in justice-involved individuals with schizophrenia. Methods: Using an experimental research design, the present study aims to examine differences in the subjective and neuroendocrine responses to psychosocial stress and its impact on facial emotion recognition (FER) and performance on an arithmetic task in chronically ill justice-involved individuals with schizophrenia (PAT) and a healthy control group. PAT undergoing treatment in forensic psychiatric inpatient wards (n = 17) and a healthy control group (n = 17) were assessed regarding sociodemographic and clinical characteristics. Additionally, salivary cortisol levels, measured before and after performing a psychosocial stress task [Montreal Imaging Stress Task (MIST)], and performance on an arithmetic problem-solving task and two FER tasks were recorded. Two participants dropped out, one from each group. Therefore, the final sample consisted of 32 individuals. Results: Significant group differences in FER were recorded. There was a significant rise in subjective perception of momentary strain relating to the induction of psychosocial stress in both groups. Notably, the pre-stress level of subjective strain was higher in the PAT group than controls. Acute psychosocial stress induced an increase in FER performance in a sub-task related to naming emotions in individuals with schizophrenia spectrum disorder. Discussion: The results underline the importance of psychosocial and therapeutic interventions aimed at strengthening stress resilience in individuals with schizophrenia spectrum disorders.

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This study examined the effect of a serial multiple exemplar training (S-MET) procedure on bidirectional naming (BiN) in four preschool children diagnosed with autism spectrum disorder (ASD). A non-concurrent multiple baseline design was used to evaluate the effects of training listener and speaker behavior for one stimulus at a time until BiN occurred. When BiN occurred, probes were conducted to measure whether generalization occurred across settings and people. Three out of four participants' responding met the mastery criterion for BiN, while the fourth participant improved her performance. The results of this study suggest that S-MET may be a promising intervention and contribute to our knowledge about learning histories required for BiN.

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In the current study, eight college students were exposed to a successive matching-to-sample (S-MTS) procedure utilizing non-verbal auditory stimuli consisting of common sounds. During emergent relations tests, participants were asked to talk aloud, and their vocal-verbal statements were transcribed and categorized as class-consistent, class-inconsistent, or irrelevant. All participants met emergence criterion for symmetry and four did so for transitivity/equivalence. Analysis of vocal-verbal statements showed a positive correlation between class-consistent statements emitted by participants and correct selection responses during S-MTS tasks. Such results suggest possible verbal mediation during emergent relations tests.

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In two speech production studies conducted in Italian, we investigated the impact of phonological neighbourhood properties such as the neighbourhood density and the mean frequency of the neighbours on speech processing. Two populations of healthy (Study 1) and neurologically impaired (Study 2) individuals were tested. We employed multi-regression methods to analyse naming latencies in Study 1 and accuracy rates in Study 2 while controlling for various psycholinguistic predictors. In Study 1, pictures with words from high-density neighbourhoods were named faster than those from low-density neighbourhoods. Additionally, words with high-frequency neighbours were named faster in Study 1 and yielded higher accuracy rates in Study 2. The results suggest facilitatory effects of both the phonological neighbourhood density and frequency neighbourhood variables. Furthermore, we observed interactions between these two phonological neighbourhood variables and name agreement and repetition. Specifically, the facilitation effect was more pronounced for pictures with lower name agreement and during the initial presentation of the pictures. These findings are discussed in the context of previous literature and within the framework of interactive models of speech production.

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In the present study, we aimed to investigate the different impacts of temporal processing on reading by Chinese children with and without dyslexia. In total, 27 children with dyslexia who had a deficit in rapid automatized naming (RAN) (D_R), 37 children with dyslexia who had deficits in both RAN and phonological awareness (PA) (D_RP), and 40 typically developing children (TD) were recruited in Taiwan. The children were asked to complete non-verbal intelligence, PA, RAN, Chinese character reading tasks and an auditory temporal order judgement (ATOJ) task. Our results of a multiple regression model showed that the ATOJ accounted for unique variances in the reading differences between the children in the D_R and TD groups; performance was controlled for non-verbal intelligence, PA and RAN tasks. Theoretically, we provide possible explanations for the controversial findings in the field of Chinese children with dyslexia and, practically, suggest different interventions should be provided for children with dyslexia with different underlying impairments.

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