No abstract

The current study aims to determine the brain areas critical for response to anodal transcranial direct current stimulation (tDCS) in PPA. Anodal tDCS and sham were administered over the left inferior frontal gyrus (IFG), combined with written naming/spelling therapy. Thirty people with PPA were included in this study, and assessed immediately, 2 weeks, and 2 months post-therapy. We identified anatomical areas whose volumes significantly predicted the additional tDCS effects. For trained words, the volumes of the left Angular Gyrus and left Posterior Cingulate Cortex predicted the additional tDCS gain. For untrained words, the volumes of the left Middle Frontal Gyrus, left Supramarginal Gyrus, and right Posterior Cingulate Cortex predicted the additional tDCS gain. These findings show that areas involved in language, attention and working memory contribute to the maintenance and generalization of stimulation effects. The findings highlight that tDCS possibly affects areas anatomically or functionally connected to stimulation targets.

Background: Aphasia therapy focusing on abstract properties of language promotes both item-specific effects and generalization to untreated materials. Neuromodulation with transcranial Direct Current Stimulation (tDCS) has been shown to enhance item-specific improvement, but its potential to enhance generalization has not been systematically investigated. Here, we test the efficacy of ACTION (a linguistically motivated protocol) and tDCS in producing item-specific and generalized improvement in aphasia.Method: Nine individuals with post-stroke aphasia participated in this study. Participants were pre-tested with a diagnostic language battery and a cognitive screening. Experimental tasks were administered over multiple baselines. Production of infinitives, of finite verbs and of full sentences were assessed before and after each treatment phase. Nonword repetition was used as a control measure. Each subject was treated in two phases. Ten daily 1-h treatment sessions were provided per phase, in a double-blind, cross-over design. Linguistically-motivated language therapy focusing on verb inflection and sentence construction was provided in both phases. Each session began with 20 min of real or sham tDCS. Stimulation site was determined individually, based on MRI scans.Results: Group data showed improved production of treated and untreated verbs, attesting the efficacy of behavioral treatment, and its potential to yield generalization. Each individual showed significant item-specific improvement. Generalization occurred in the first phase of treatment for all subjects, and in the second phase for two subjects. Stimulation effects at the group level were significant for treated and untreated verbs altogether, but a ceiling effect for Sham cannot be excluded, as scores between real tDCS and Sham differed only before treatment.Conclusion: Our data demonstrate the efficacy of ACTION and suggest that tDCS may enhance both item-specific effects and generalization.

Electrical Stimulation (ES) is a neurostimulation technique that is used to localize language functions in the brain of people with intractable epilepsy and/or brain tumors. We reviewed 25 ES articles published between 1984 and 2018 and interpreted them from a cognitive neuropsychological perspective. Our aim was to highlight ES as a tool to further our understanding of cognitive models of language. We focused on associations and dissociations between cognitive functions within the framework of two non-neuroanatomically specified models of language. Also, we discussed parallels between the ES and the stroke literatures and showed how ES data can help us to generate hypotheses regarding how language is processed. A good understanding of cognitive models of language is essential to motivate task selection and to tailor surgical procedures, for example, by avoiding testing the same cognitive functions and understanding which functions may be more or less relevant to be tested during surgery.

There is an emerging trend towards following similar practices for the management of low-grade gliomas in Europe. Our results are descriptive and formalise current discussions in our group. Also, they contribute towards the development of a European assessment protocol.

During awake surgery, picture-naming tests are administered to identify brain structures related to language function (language mapping), and to avoid iatrogenic damage. Before and after surgery, naming tests and other neuropsychological procedures aim at charting naming abilities, and at detecting which items the subject can respond to correctly. To achieve this goal, sufficiently large samples of normed and standardized stimuli must be available for preoperative and postoperative testing, and to prepare intraoperative tasks, the latter only including items named flawlessly preoperatively. To discuss design, norming and presentation of stimuli, and to describe the minimal standardization setting used to develop two sets of Italian stimuli, one for object naming and one for verb naming, respectively. The setting includes a naming study (to obtain picture-name agreement ratings), two on-line questionnaires (to acquire age-of-acquisition and imageability ratings for all test items), and the norming of other relevant language variables. The two sets of stimuli have >80 % picture-name agreement, high levels of internal consistency and reliability for imageability and age of acquisition ratings. They are normed for psycholinguistic variables known to affect lexical access and retrieval, and are validated in a clinical population. This framework can be used to increase the probability of reliably detecting language impairments before and after surgery, to prepare intraoperative tests based on sufficient knowledge of pre-surgical language abilities in each patient, and to decrease the probability of false positives during surgery. Examples of data usage are provided. Normative data can be found in the supplementary materials.

Background Animal fluency is a widely used task to assess people with Alzheimer’s disease (AD) and other neurological disorders. The mechanisms that drive performance in this task are argued to rely on language and executive functions. However, there is little information regarding what specific aspects of these cognitive processes drive performance on this task. Objective To understand which aspects of language (i.e., semantics, phonological output lexicon, phonological assembly) and executive function (i.e., mental set shifting; information updating and monitoring; inhibition of possible responses) are involved in the performance of animal fluency in people with AD. Methods Animal fluency data from 58 people with probable AD from the DementiaBank Pittsburgh Corpus were analyzed. Number of clusters and switches were measured and nine word properties (e.g., frequency, familiarity) for each of the correct words (i.e., each word counting toward the total score, disregarding non-animals and repetitions) were determined. Random forests were used to understand which variables predicted the total number of correct words, and conditional inference trees were used to search for interactions between the variables. Finally, Wilcoxon tests were implemented to cross-validate the results, by comparing the performance of participants with scores below the norm in animal fluency against participants with scores within the norm based on a large normative sample. Results Switches and age of acquisition emerged as the most important variables to predict total number of correct words in animal fluency in people with AD. Cross-validating the results, people with AD whose animal fluency scores fell below the norm produced fewer switches and words with lower age of acquisition than people with AD with scores in the normal range. Conclusion The results indicate that people with AD rely on executive functioning (information updating and monitoring) and language (phonological output lexicon, not necessarily semantics) to produce words on animal fluency.

Adults with COPD frequently present with dysphagia, which often leads to clinical complications and hospital admissions. This study investigates the ability of the Eating Assessment Tool (EAT-10) to predict aspiration during objective dysphagia evaluation in adults with stable COPD. Thirty adults (20 male, 10 female; mean age = 69.07 ± 16.82) with stable COPD attended an outpatient dysphagia clinic for a fiberoptic endoscopic evaluation of swallowing (FEES) in an acute teaching hospital (January 2015-November 2016). During evaluations, individuals completed an EAT-10 rating scale followed immediately by a standardised FEES exam. Aspiration status during FEES was rated using the penetration-aspiration scale by clinicians blinded to EAT-10 scores. Data were retrospectively analysed. Significant differences in mean EAT-10 scores were found between aspirators (16.3; SEM = 2.165) and non-aspirators (7.3; SEM = 1.009) (p = 0.000). The EAT-10 predicted aspiration with a high level of accuracy (AUC = 0.88). An EAT-10 cut-off value of >9 presented a sensitivity of 91.67, specificity of 77.78 with positive and negative likelihood ratios of 4.12 and 0.11, respectively. Positive and negative predictive values were 73.30 and 93.30, respectively. Diagnostic odds ratio was 38.50 (p < 0.01, CI 3.75-395.42). EAT-10 is a quick, easy to administer tool, which can accurately predict the presence of aspiration in adults with COPD. The scale can also very accurately exclude the absence of aspiration, helping clinicians to determine the need for onward referral for a comprehensive dysphagia evaluation. This may ultimately reduce clinical complications and hospital admissions resulting from dysphagia in this clinical population.