Verb Frequency and Density Drive Naming Performance in Primary Progressive Aphasia.

Background: Recent work has highlighted the utility of the Boston Naming Test and Hopkins Action Naming Assessment (HANA) for distinguishing between semantic (svPPA), logopenic (lvPPA) and non-fluent agrammatic (nfavPPA) variants of primary progressive aphasia (PPA). Aims: To determine whether item level differences between variants on when naming verbs on the HANA were able to be accounted for using common variables of lexical interest: word frequency, semantic density, concreteness, or valency. We also examined three specific hypotheses: (1) svPPA and lvPPA may result in increased difficulty with decreased semantic density compared to nfavPPA; (2) svPPA may result in increased difficulty with decreased concreteness; and (3) nfavPPA may result in increased difficulty with high syntactic valency. Methods & Procedures: 268 patients with PPA were evaluated using the HANA. A hierarchical Bayesian regression approach was adopted to account for effects of repeated measurement within participants and items. Outcomes & Results: The main effects of variant and verb trait were significant in all models, as was the interaction for frequency, semantic density, and valency. Increasing frequency, semantic density, and concreteness led to better performance, while increasing valency led to poorer performance. Low semantic density contributed to greater difficulty in svPPA and lvPPA, but low concreteness did not uniquely impact verb naming in svPPA. Those with nfavPPA had no particular difficulty as a result of valency. Conclusions: Prior studies have identified the independent effects of frequency and semantic density on verb naming in PPA, which were confirmed by our analyses, and the best predictions of the data were achieved by combining these dimensions. This investigation complements our previous work highlighting the value of the HANA for efficiently demonstrating verb performance in PPA.

Association of inferior division MCA stroke location with populations with atrial fibrillation incidence.

BACKGROUND AND AIM: Considering the anatomical features of Middle Cerebral Artery (MCA) bifurcation, larger emboli are more likely to enter the inferior division over the superior division. Since emboli of cardiac origin are larger on average than emboli of arterial origin, we hypothesize that the infarcts in temporal and parietal lobes are more likely associated to atrial fibrillation than those in the frontal lobes, therefore occurring more often in populations with higher incidence of atrial fibrillation, such as male (compared to women) and white (compared to black) patients. METHODS: We included 197 patients with MCA "temporoparietal predominant" infarcts and 105 with "frontal predominant" infarcts. Variations between stroke location (frontal or temporoparietal), sex, and race were examined via Chi-square test. RESULTS: Male patients were more likely than female patients to be afflicted by temporoparietal strokes versus frontal strokes, while white patients had greater likelihood than black patients to be afflicted by temporoparietal strokes versus frontal strokes. Patients with confirmed diagnosis of atrial fibrillation display more temporoparietal strokes compared to frontal strokes. CONCLUSION: Temporoparietal MCA ischemic strokes occur more frequently in male and white patients: populations with known increased incidence of atrial fibrillation. In addition, population-specific anatomical characteristics of the MCA bifurcation might favor the larger cardiac emboli to enter the inferior division and cause temporoparietal infarcts. This association can help guide search for the most likely etiology of infarcts.

Transcranial Direct-Current Stimulation in Subacute Aphasia: A Randomized Controlled Trial.

BACKGROUND: Transcranial direct-current stimulation (tDCS) is a promising adjunct to therapy for chronic aphasia. METHODS: This single-center, randomized, double-blind, sham-controlled efficacy trial tested the hypothesis that anodal tDCS augments language therapy in subacute aphasia. Secondarily, we compared the effect of tDCS on discourse measures and quality of life and compared the effects on naming to previous findings in chronic stroke. Right-handed English speakers with aphasia <3 months after left hemisphere ischemic stroke were included, unless they had prior neurological or psychiatric disease or injury or were taking certain medications (34 excluded; final sample, 58). Participants were randomized 1:1, controlling for age, aphasia type, and severity, to receive 20 minutes of tDCS (1 mA) or sham-tDCS in addition to fifteen 45-minute sessions of naming treatment (plus standard care). The primary outcome variable was change in naming accuracy of untrained pictures pretreatment to 1-week posttreatment. RESULTS: Baseline characteristics were similar between the tDCS (N=30) and sham (N=28) groups: patients were 65 years old, 53% male, and 2 months from stroke onset on average. In intent-to-treat analysis, the adjusted mean change from baseline to 1-week posttreatment in picture naming was 22.3 (95% CI, 13.5-31.2) for tDCS and 18.5 (9.6-27.4) for sham and was not significantly different. Content and efficiency of picture description improved more with tDCS than sham. Groups did not differ in quality of life improvement. No patients were withdrawn due to adverse events. CONCLUSIONS: tDCS did not improve recovery of picture naming but did improve recovery of discourse. Discourse skills are critical to participation. Future research should examine tDCS in a larger sample with richer functional outcomes. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02674490.

Emotional and qualitative outcomes among patients with left and right hemisphere stroke.

The differences in mental health outcomes of right and left hemisphere strokes are well studied; however, there is a long-standing controversy surrounding whether depression is associated with lateralization of stroke or not. In this investigation, we examined the effect of lesion location on post-stroke depression controlling for lesion size and hemiparesis in a longitudinal sample assessed at acute, subacute, and chronic timepoints. As a secondary aim, we further examined the effect of lesion location on self-reported difficulties across a wide array of domains. A series of 134 patients with left hemisphere strokes and 79 with right hemisphere strokes completed the Patient Health Questionnaire-9 and an inventory of post-stroke abilities at within acute, subacute, and chronic windows following stroke. When controlling for hemiparesis and overall lesion volume, we found no difference in depression between groups at any timepoint. Additional exploratory analyses provided a further look at differing challenges associated with depression in each group.

Enhanced Imaging and Language Assessments for Primary Progressive Aphasia.

BACKGROUND AND OBJECTIVES: It is widely agreed that primary progressive aphasia (PPA) is a clinical syndrome with at least 3 distinct variants that differ in phenotype, areas of atrophy, and most common underlying neurodegenerative disease. The distinction between logopenic variant PPA (lvPPA) and other variants is important for prognosis and medical management. However, differentiating logopenic from nonfluent agrammatic variant can be difficult. We aimed to identify a novel behavioral assessment that (1) distinguishes logopenic from the other variants with a high degree of accuracy and (2) correlates with left superior temporal-inferior parietal atrophy (previously shown to be associated with this variant). The location of atrophy was measured using a novel, clinically useful imaging analysis. METHODS: In this observational cohort study of 227 individuals with PPA, participants were administered sentence reading and repetition subtests from a standard battery. A subset of 41 participants were administered enhanced reading and repetition subtests with 5 longer sentences, of which 13 had brain imaging. Ratios of word-level and sentence-level accuracy in reading:repetition were calculated. We used one-way analysis of variance (ANOVA) to determine whether either or both ratios of reading:repetition independently discriminated between variants and t test to determine whether the ratios distinguished between nonfluent and logopenic variants. We identified receiver operating characteristics and Pearson correlations between the reading:repetition ratios and ratio of left:right superior temporal-inferior parietal volume. RESULTS: The sentence reading:repetition ratio using the new stimuli significantly differed across the 3 variants (p < 0.00001) and differed between nonfluent and logopenic variants (t(27) = 4.1; p = 0.0003). The area under the curve for distinguishing logopenic from other variants was 0.85 (0.71-0.99), and the diagnostic accuracy was 87.5%. The sentence reading:repetition ratio correlated with left:right superior temporal-inferior parietal volume (r = 0.69; p = 0.0087), but not with left:right volume of regions of interest associated with other variants. DISCUSSION: Results provide an efficient and reliable clinical assessment, and a novel imaging analysis, to distinguish the clinical syndrome of logopenic variant from other variants of PPA. Results also support the proposal that lvPPA reflects a defect in phonological short-term memory caused by atrophy in the superior temporal-inferior parietal cortex. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that the sentence reading:repetition ratio distinguished logopenic PPA from other PPA variants.

Left Hemisphere Bias of NIH Stroke Scale Is Most Severe for Middle Cerebral Artery Strokes.

NIHSS score is higher for left vs. right hemisphere strokes of equal volumes. However, differences in each vascular territory have not been evaluated yet. We hypothesized that left vs. right differences are driven by the middle cerebral artery (MCA) territory, and there is no difference between hemispheres for other vascular territories. This study is based on data from 802 patients with evidence of acute ischemic stroke in one major arterial territory (MCA, n = 437; PCA, n = 209; ACA, n = 21; vertebrobasilar, n = 46). We examined differences in patients with left or right strokes regarding to lesion volume, NIHSS, and other covariates (age, sex, race). We used linear models to test the effects of these covariates on NIHSS. We looked at the whole sample as well as in the sample stratified by NIHSS (≤5 or >5) and by lesion location (MCA or PCA). Patients with left MCA strokes had significantly higher NIHSS than those with right strokes. Only patients with MCA strokes showed NIHSS score affected by the hemisphere when controlling for stroke volume and patient's age. This difference was driven by the more severe strokes (NIHSS>5). It is important to consider this systematic bias in the NIHSS when using the score for inclusion criteria for treatment or trials. Patients with right MCA stroke may be under-treated and left with disabling deficits that are not captured by the NIHSS.

Dysfunctional Tissue Correlates of Unrelated Naming Errors in Acute Left Hemisphere Stroke.

Most naming error lesion-symptom mapping (LSM) studies have focused on semantic and/or phonological errors. Anomic individuals also produce unrelated word errors, which may be linked to semantic or modality-independent lexical deficits. To investigate the neural underpinnings of rarely-studied unrelated errors, we conducted LSM analyses in 100 individuals hospitalized with a left hemisphere stroke who completed imaging protocols and language assessments. We used least absolute shrinkage and selection operator regression to capture relationships between naming errors and dysfunctional brain tissue metrics (regional damage or hypoperfusion in vascular territories) in two groups: participants with and without impaired single-word auditory comprehension. Hypoperfusion-particularly within the parietal lobe-was an important error predictor, especially for the unimpaired group. In both groups, higher unrelated error proportions were associated with primarily ventral stream damage, the language route critical for processing meaning. Nonetheless, brain metrics implicated in unrelated errors were distinct from semantic error correlates.

Task performance to discriminate among variants of primary progressive aphasia.

Primary progressive aphasia can be distinguished into one of three variants: semantic, non-fluent/agrammatic, and logopenic. While a considerable body of work exists characterizing each variant, few prior studies have addressed the problem of optimizing behavioral assessment in a typical outpatient evaluation setting. Our aim is to examine the sensitivity and specificity of a battery of cognitive and linguistic assessments and determine optimal scores for distinguishing patients' subtype based on these instruments. This was a retrospective analysis of outpatient clinical testing of individuals with known or suspected primary progressive aphasia. Evaluations included the National Alzheimer's Coordinating Center frontotemporal lobar degeneration module and additional measures of naming, semantic association, word verification, and picture description. Receiver operating characteristic analysis was used to examine the utility of each task in distinguishing each variant from the others. Logistic regressions were used to examine the combined utility of tasks for distinguishing a given subtype. We examined 435 evaluations of 222 patients retrospectively. The battery was most consistent in distinguishing semantic variant by low scores and non-fluent/agrammatic variant by high scores on a similar subset of tasks. Tasks best distinguishing semantic variant produced a model that correctly classified 86% of cases. Tasks best distinguishing non-fluent/agrammatic variant correctly classified 77% of cases. The battery of tasks was weakest in identifying logopenic variant; only the ratio of sentence reading to sentence repetition performance was identified as a reasonable predictor, and it had predictive accuracy of 67%. Naming assessments were the strongest basis for distinguishing all variants, particularly semantic variant from non-fluent/agrammatic variant. These data illustrate that a number of commonly used assessments perform at chance in distinguishing variant and preliminarily support an abbreviated battery that marginally favors tools not currently included in the frontotemporal lobar degeneration module.

Treatment of post-stroke aphasia: A narrative review for stroke neurologists.

This review is intended to help physicians guide patients to optimal management of post-stroke aphasia. We review literature on post-stroke aphasia treatment, focusing on: (1) when and for whom language therapy is most effective, (2) the variety of approaches that can be effective for different individuals, and (3) the extent to which behavioral therapy might be augmented by non-invasive brain stimulation and/or medications.

Stability of Speech Intelligibility Measures Over Repeated Sampling Times in Speakers With Acquired Apraxia of Speech.

Purpose The purpose of this investigation was to measure the test-retest stability of single-word intelligibility in a group of 28 speakers with chronic apraxia of speech and aphasia. Method The Assessment of Intelligibility of Dysarthric Speech was administered twice to each participant, with samples separated by 1 week. Scoring of recorded samples was completed independently by three expert listeners using transcription and multiple-choice scoring formats. Results Percent intelligible words was very similar for the group over the two sampling times for both scoring formats (i.e., within 1.5%), with no statistically significant differences found between times. Statistically significant, very strong, positive correlations were found between sampling times for intelligibility scores. Transcription and multiple-choice scores were strongly, positively correlated, with multiple-choice scores being statistically higher. There was a statistically significant difference between mean transcription and multiple-choice scores for the group at Time 1 and Time 2. Individual performance was similar to group performance for the majority of participants. Conclusions These findings indicate that single-word intelligibility measures are stable over repeated sampling occasions. Stability was evident for transcription and multiple-choice scoring methods. Supplemental Material https://doi.org/10.23641/asha.14226737.