Cross-linguistic asymmetries in language production and code-switching patterns in bilingual aphasia

A longitudinal study of oral and written naming and comprehension of nouns and verbs in an individual (M. M. L.) with nonfluent primary progressive aphasia (PPA) is reported. M. M. L. showed progressive deterioration of oral naming of verbs well before deterioration of written naming of verbs and before deterioration of oral or written naming of nouns. Her comprehension of both nouns and verbs remained intact, at least relative to oral naming of verbs. Her performance is compared to that of two other individuals with nonfluent PPA, who were tested at two time points. These patients showed similar patterns with respect to grammatical word class (verbs more impaired than nouns) and modality (spoken production more impaired than written production), but somewhat different courses of deterioration. The modality-specific nature of the observed verb production deficits rules out a semantic locus for the grammatical class effects. The results provide a new source of evidence for the hypothesis that there are distinct neural mechanisms for accessing lexical representations of nouns and verbs in language production.

ABSTRACTBackground: Dissociated impairment of noun and verb retrieval has been frequently reported after vascular brain lesions: selective damage of either grammatical class allowed to test models of lexical processing and of its neuroanatomical foundation. However, vascular lesions are often quite large and do not involve brain structures uniformly. Neurosurgical lesions do not undergo such apparent limitation, being usually smaller and better distributed across the cerebral cortex.Aims: We explored the neuroanatomical correlates of noun–verb naming processing and dissociations by means of the voxel-based lesion symptom mapping (VLSM) procedure and the subtraction of lesion volume of interests (VOIs) approach in a series of 99 neurosurgical patients.Methods and Procedures: The VOIs and behavioral data for noun and verb naming were analyzed in a VLSM procedure. The verb (or noun) naming performance was included as a covariate control variable, which allowed testing effects on noun (or verb) naming, controlling for the verb (or noun) naming performance. The total lesion volume was also included as a covariate to avoid spurious effects.Outcomes and Results: Eighteen patients showed a significant dissociation between noun and verb naming: seven patients showed disproportionate impairment in naming nouns, and eleven patients with disproportionate impairment in naming verbs. In addition, there were 27 undifferentiated patients, i.e. performing abnormally on nouns and/or verbs, but non-dissociating between the two word classes.VLSM in combination with the subtraction of lesion mask analyses revealed that verb naming impairments were related with lesions in the middle frontal gyrus, precentral gyrus, parietal and rolandic operculum, supplementary motor area, and the inferior parietal (supramarginal and angular gyri), whereas noun naming impairments were associated with basal temporo-occipital lesions. Furthermore, data indicate that noun and verb naming deficits also depend on a disconnection phenomenon: at subcortical level, noun naming impairments are related to damage to parts of the sagittal stratum (including the inferior fronto-occipital fasciculus and the inferior longitudinal fasciculus), the splenium of the corpus callosum, the posterior thalamic radiations (plus optic radiations), the retrorolandic part of the internal capsule, the tapetum and the fornix. On the contrary, verb naming impairments are related to damage to parts of the superior and posterior corona radiata, and of the anterior and posterior limb of the internal capsule.Conclusions: Summing up, results point to verb-specific areas in the superior frontal as well as the inferior parietal cortex, and noun-specific basal temporo-occipital and subcortical neural circuitries.

In our daily life, we often encounter situations in which different features of several multidimensional objects must be perceived simultaneously. There are two types of environments of this kind: environments with multidimensional objects that have unique feature associations, and environments with multidimensional objects that have mixed feature associations. Recently, we (Goldfarb & Treisman, 2013) described the association effect, suggesting that the latter type causes behavioral perception difficulties. In the present study, we investigated this effect further by examining whether the effect is determined via a feedforward visual path or via a high-order task demand component. In order to test this question, in Experiment 1 a set of multidimensional objects were presented while we manipulated the letter case of a target feature, thus creating a visually different but semantically equivalent object, in terms of its identity. Similarly, in Experiment 2 artificial groups with different physical properties were created according to the task demands. The results indicated that the association effect is determined by the task demands, which create the group of reference. The importance of high-order task demand components in the association effect is further discussed, as well as the possible role of the neural synchrony of object files in explaining this effect.

Background: The role of cognateness in bilingual language production has been the focus of much investigation. Many studies have found a cognate facilitation effect for reaction times and accuracy in naming in control participants (Costa, Caramazza & Sebastien-Galles, 2000; Rosselli, Ardila, Jurado,& Salvatierra, 2012 ) but the findings are by no means unequivocal e.g. Siyambalapitiya et al, 2009 observed a reversal of the cognate facilitation effect in older participants. The effect of cognateness has also been investigated in aphasic participants; Roberts & Deslauriers (199) observed a strong picture naming advantage for cognate words over non-cognate words, though no individual data were reported. Several case studies have reported cognate advantage in individuals, though results vary dependent on task and on the individual (Detry, Pillon & De Partz, 2005; Lalor & Kirsner, 2001). Furthermore, an inhibitory effect for cognate words has also been observed (Tiwari & Krishnan 2015). Overall, the above findings serve to illustrate that the facilitatory effect of cognate words is uncertain, and further investigation is required. Research Question: Does task type affect the cognate advantage in Welsh-English bilingual speakers? It is expected that patients will present with a picture naming advantage for cognate items. The expectations for a cognate advantage in translation are less assured, as the presentation of a cognate word in one language may inhibit access to its translation equivalent due to the phonological overlap, or the similarity may be facilitatory in activating the phonological representation of the target. Participants: 7 Welsh-English early proficient bilingual aphasic participants were selected for participation. Each patient scored significantly lower (p<.05) than age-matched controls (N=37) on at least one task using the modified t-tests for single cases (Crawford & Howell, 1998) Methods: Picture naming and translation tasks were administered in each language. Each task included 80 items, matched across languages for frequency, word length and number of cognate items; both naming and translation probed the same words. Results and discussion: As can be seen in the Figure, the effect of cognate status was highly variable across participants, languages and tasks. Only one participant showed a robust advantage in the 4 conditions. Overall, there was little evidence for cognate facilitation in the translation task, with 4 patients even showing an inhibitory effect of cognateness. This study on an unselected group of participants suggests that cognateness effects may partly reflect a publication bias and that a full understanding of the effects of cognate status will require future investigation.

fMRI language mapping studies report right-hemispheric contribution to language in healthy individuals.However, it remains unclear whether these right-hemispheric patterns of activity are critical for language, which is highly relevant for clinical preoperative language mapping. The available findings are controversial. In this study, we first measured individual patterns of language lateralization with an fMRI language localizer in healthy participants with different handedness (N = 31). Then, the same participants received rTMS over the individual coordinates of peak fMRI-based activation in the left and right inferior frontal gyri. During rTMS, participants performed a picture naming task. It included both objects and actions to test whether naming of nouns and verbs would be equally modulated by rTMS. Stimulation of the left inferior frontal gyrus resulted in accuracy facilitation of verb production regardless of individual language lateralization. No modulation of object naming was found at any stimulation site in terms of accuracy nor reaction time. This study causally confirmed the critical contribution of the left, but not the right hemisphere to verb production regardless of the language lateralization patterns observed with fMRI. Also, the results stress that action rather than object naming is the task of choice for mapping language in the frontal lobe.

Background: The aphasiological literature has provided an extensive body of research on verb impairments but many fewer verb therapy studies. Verbs display particular complexity at various levels of linguistic analysis: phonological, morphological, semantic, and syntactic. Verb impairments can arise at any of these processing levels as well as from cognitive sources. Verb-naming therapies may therefore be relatively more vulnerable to errors, which could reduce their effectiveness. Errorless learning has been used with positive results for noun therapies. Aims: Given the high linguistic and cognitive demands of verb processing, this study investigated whether errorless therapy would be more effective for verb naming than more traditional hierarchical cueing (relatively errorful) therapy. Methods & Procedures: Nine participants with word-finding difficulties as a part of their chronic aphasia took part in the study. Outcomes & Results: For the dependent variable of naming accuracy, as in previous studies, we found that errorless therapy was as effective as errorful therapy for both verb and noun naming. Three participants with most severe aphasia showed significantly greater gains in noun as opposed to verb naming. The remaining participants exhibited comparable gains in both nouns and verb naming. There was no lasting generalisation from treated to untreated therapy items. The prediction that errorless therapy would be more effective for verb naming was not upheld; errorless and errorful approaches were as effective as one another. Conclusions: An errorless-learning approach to verb and noun naming was a time-efficient therapy, and one that was as effective as an errorful/hierarchical cueing method in improving naming accuracy, for a range of participants with varying naming skills and types of aphasia.

The Relationship Between Working Memory Capacity and L2 Oral Performance Under Task‐Based Careful Online Planning Condition

Introduction: Due to the prevalence of cognitive disorders, such as the behavioral variant of frontotemporal dementia (bvFTD) and the consequences that these disorders follow, early diagnosis and awareness of the deficiencies of these people in the cognitive and language areas is essential. Given that language is dependent on culture, examining the linguistic characteristics of such patients in different languages can provide valuable findings. Therefore, this study compares noun and verb naming abilities in individuals with bvFTD and non-patients Persian-speaking. Materials and Methods: In this cross-sectional study, 3 cognitive tests, including frontal assessment battery (FAB), Montreal cognitive assessment, and mini-mental state examination (MMSE), along with 2 noun naming and verb naming tests were performed on 15 patients with bvFTD and 30 homogeneous non-patient individuals. Results: The bvFTD group had significantly different scores for both noun and verb naming compared to the non-patient group (P&lt;0.05). Meanwhile, the bvFTD group was more impaired in naming verbs than nouns, with the largest difference between groups in the verb naming task. Conclusion: the results showed that bvFTD patients have poorer noun and verb naming abilities than non-patients. In particular, in verb naming, they showed more deficits than nouns. One possible explanation is that the processing of verbs is more complicated than nouns and involves a more complex neural system and cognitive processes than noun processing. Another possibility is that verbs rely more heavily on frontal and temporal regions of the brain, which are typically affected by bvFTD.

Verb deficits in Alzheimer’s disease and agrammatism: Implications for lexical organization

The influence of task demand and social categorization diversity on performance and enjoyment in a language learning game

Mapping cortical activations underlying covert and overt language production using high-density diffuse optical tomography

The influence of task demand and learning on the psychophysiological response

Children with developmental language disorder (DLD) are poor at story-telling and show weaknesses in various executive functions (EFs). Narrative tasks are frequently used in clinical assessment to capture the linguistic vulnerabilities of individuals with DLD. But we know little about the demands of different narrative tasks on EFs. This study explores the relationship between EFs in a daily life context and performance on two narrative tasks. Fourteen Mandarin-speaking preschoolers with DLD and 34 typically-developing (TD) controls completed a story generation and a story recall task. Their parents filled out the Behavior Rating Inventory of Executive Functions-Preschool (BRIEF-P). The TD group outperformed the DLD group on narrative macrostructure and microstructure, and the inhibit, shift, and global executive composites of the BRIEF-P. On the story recall task, after controlling for standardised language test scores, working memory scores explained unique variance in both narrative macrostructure and microstructure performance. On the story generation task, after controlling for language skills, macrostructure performance was predicted by inhibit, working memory, and plan/organisation composites, and microstructure performance was predicted by the inhibit composite. Narrative recall relies heavily on working memory capacity as children must recall the details provided in the mature adult model; narrative generation requires multiple EFs as children must plan the organisation of story elements, selectively attend to relevant visual details in the pictorial stimuli, and monitor their own language production. The findings have implications for understanding the sources of language difficulties in DLD and the selection of narrative task in clinical practice.

Consequences of bi-literacy in bilingual individuals: in the healthy and neurologically impaired

Primary progressive aphasia (PPA) is a dementia syndrome whose onset and course manifests with language deficits. There is a lack of instruments for clinical assessment of language in dementia and further research in the area is needed. Therefore, the objective of the present study was to identify language tasks that can aid the process of clinically diagnosing PPA and to determine those tasks most impaired in this population. A sample of 87 individuals comprising 2 groups was assessed: a PPA group (PPAG) of 29 PPA patients; and a control group (CG) of 58 healthy subjects matched for age and education. All participants underwent a brief cognitive battery followed by a comprehensive language assessment using the MTL-BR Battery. A statistically significant performance difference was found between the PPAG and CG on the following tasks: structured interview, oral comprehension of phrases, oral narrative discourse, written comprehension of phrases, written dictation, sentence repetition, semantic verbal fluency, oral naming of nouns and verbs, object manipulation, phonological verbal fluency, body part recognition and left-right orientation, written naming of nouns, oral text comprehension, number dictation, written narrative discourse, written text comprehension and numerical calculations (mental and written). The results revealed that performance of PPA patients was poorer compared to healthy subjects on various language tasks. The most useful subtests from the MTL-BR battery for aiding clinical diagnosis of PPA were identified, tasks which should be prioritized when assessing this patient group.