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Using a novel dataset, this brief note investigates the effect of female labor force participation (FLFP) on three important variables, profit shares, profit rates, and capital-output ratio, covering a very large set of countries (i.e., 130) over a recent time period of 1990-2019. This paper shows that while FLFP increases profit share in high-income countries, it reduces in middle-income countries. However, for both middle- and high-income countries, FLFP cannot prevent the overall tendency in profit rates to decline caused by a consistent decline in output-capital ratio.

Coregonine fishes are important to Laurentian Great Lakes food webs and fisheries and are central to basin-wide conservation initiatives. In Lake Ontario, binational management objectives include conserving and restoring spawning stocks of cisco (Coregonus artedi) and lake whitefish (C. clupeaformis), but the spatial extent of contemporary coregonine spawning habitat and the environmental factors regulating early life success are not well characterized. In Spring 2018, we conducted a binational ichthyoplankton assessment to describe the spatial extent of coregonine spawning habitat across Lake Ontario. We then quantified the relative importance of a suite of biophysical variables hypothesized to influence coregonine early life success using generalized additive mixed models and multimodel inference. Between April 10 and May 14, we conducted 1,092 ichthyoplankton tows and captured 2,350+ coregonine larvae across 17 sampling areas, predominantly within embayments. Although 95% of catches were in the eastern basin, coregonine larvae were also found in historical south shore spawning areas. Most coregonine larvae were cisco

Purpose Caregiver burden negatively impacts both stroke survivor and caregiver well-being. Thus, it is important to better understand the individual- and dyadic-level variables that may contribute to dysphagia-related caregiver burden. The aim of this preliminary study was to identify survivor-, caregiver-, and dyadic-specific factors associated with burden in couples experiencing poststroke dysphagia. Method Twenty-eight stroke survivors (“care recipients”) with dysphagia and their spouses (“caregivers”) participated. Care recipients and caregivers completed a survey from which scores for the following variables were derived: dysphagia-related caregiver burden, survivor- and spouse-perceived impact of dysphagia on mealtimes (social, mealtime logistics), dyadic congruence on perceived impact, International Dysphagia Diet Standardisation Initiative Functional Diet Scale, Swallowing-Related Quality of Life Scale, and Stroke Impact Scale (cognitive, emotional, physical, and social domains). Spearman's rho and point biserial correlation coefficients were calculated to determine the factors related to caregiver burden. Results Increased burden was significantly associated with greater care recipient– and spouse-perceived impact of dysphagia on mealtime logistics; however, burden was not associated with measures of dyadic congruence of perceived impact. Notably, increased burden was also associated with increased diet restrictiveness and decreased swallow-specific quality of life. Dysphagia-related caregiver burden was not associated with measures of stroke impact/severity across any domain. Conclusions Factors related to dysphagia-related caregiver burden are multifactorial and include both care recipient (e.g., International Dysphagia Diet Standardisation Initiative Functional Diet Scale, Swallowing-Related Quality of Life Scale, perceived impact of dysphagia on mealtime logistics) and caregiver (e.g., perceived impact of dysphagia on mealtime logistics) variables. The results of this preliminary investigation support the need to incorporate aspects of counseling and family-centered care into our management practices, a growing area of interest for speech-language pathologists.

The fundamental operation of the switched reluctance motor (SRM) is arguably the simplest and most eloquent of all the universe of rotary electromagnetic machines. Contrast the elementary operation and construction, with the highly non-linear effects that the material properties and geometrical construction of the core add to the design process. A consequence of these complexities, the efficient performance of an SRM requires an insight intensive, multivariable and highly iterative design process. For completeness, a literature survey is offered which presents a detailed review of three key papers that were instrumental in furthering the understanding of concepts, as related to; the fundamental operation, modeling and prediction methods and objective based design for the switched reluctance motor. In addition, two complete sections are reserved to review the fundamental concepts of the magnetic theory and the principles of SRM operation and design. From this review of theory and the available literature, it is clear that in order to reduce the complexity of the multivariable optimization problems associated with the complex SRM design, a method is required that can identify the significant variables in order to remove the non-significant variables from the objective functioni this is commonly referred to parameter screening. This screening process can be facilitated by using factorial design, which is a powerful tool that can be used to test several variables simultaneously in order to determine their significance. The factorial design methodology was applied to a switched reluctance motor, whereby the design parameters were individually screened for their contribution towards the starting torque, aligned/unaligned flux-linkage and the RMS stroke torque. Due to the complexity, sheer number and likely interaction of the critical variables associated with SRM design, a method is described wherein the interaction and criticality of the interactions are sorted through an iterative process; whereby, the least important variables and interactions are weeded out so that the more critical variables and interactions can be studied and rated as to their importance to the outcome of the design process. important variables and interactions are weeded out so that the more critical variables and interactions can be studied and rated as to their importance to the outcome of the design process.

Research Objectives To identify individual- and dyadic-level factors associated with caregiver burden in couples experiencing post-stroke swallowing difficulties (dysphagia). As burden negatively impacts survivor and caregiver well-being, it is important to understand the variables that contribute to post-stroke caregiver burden. Design Cross-sectional online survey. Setting General community. Participants A volunteer sample of 28 adult stroke survivors with dysphagia (mean age 60 years) and their spouses (mean age 57 years). Survivors were >3 months post-stroke (median 12.5 months) and living with their spouse who was providing some degree of caregiving. Interventions Not applicable. Main Outcome Measures Dependent variable: dysphagia-related caregiver burden. Independent variables: swallowing-specific quality of life; stroke impact (Stroke Impact Scale; SIS); dietary restrictiveness (based on consumption of texture modified food and drink); survivor, spouse, and dyadic congruence of appraisal of dysphagia's impact on the social aspect and logistics of mealtimes (e.g., socializing during meals; meal preparation). Results Increased burden was significantly associated with greater survivor- and spouse-perceived impact of dysphagia on the logistics of mealtimes (r=.547, p=.002 and r=.758, p Conclusions Factors related to dysphagia-related caregiver burden are multifactorial and include both survivor (dietary restrictiveness, swallowing-specific quality of life, perceived impact of dysphagia on mealtime logistics) and spousal (perceived impact of dysphagia on mealtime logistics) variables. These results support the interrelatedness of stroke survivor and caregiver health and well-being. There is a need for speech-language pathologists and other rehabilitation professionals to focus on the lived experience of both patients and their families in developing treatment plans. Further, incorporating increased dietary education and counseling into dysphagia management may facilitate reduced burden for stroke survivors and their families. Author(s) Disclosures Nothing to disclose.

Purpose: The neural mechanisms that support aphasia recovery are not yet fully understood. Our goal was to evaluate longitudinal changes in naming recovery in participants with posterior cerebral artery (PCA) stroke using a case-by-case analysis. Methods: Using task based and resting state functional magnetic resonance imaging (fMRI) and detailed language testing, we longitudinally studied the recovery of the naming network in four participants with PCA stroke with naming deficits at the acute (0 week), sub acute (3–5 weeks), and chronic time point (5–7 months) post stroke. Behavioral and imaging analyses (task related and resting state functional connectivity) were carried out to elucidate longitudinal changes in naming recovery. Results: Behavioral and imaging analysis revealed that an improvement in naming accuracy from the acute to the chronic stage was reflected by increased connectivity within and between left and right hemisphere “language” regions. One participant who had persistent moderate naming deficit showed weak and decreasing connectivity longitudinally within and between left and right hemisphere language regions. Conclusions: These findings emphasize a network view of aphasia recovery, and show that the degree of inter- and intra- hemispheric balance between the language-specific regions is necessary for optimal recovery of naming, at least in participants with PCA stroke.

The insula has been implicated in many sequelae of stroke. It is the area most commonly infarcted in people with post-stroke arrhythmias, loss of thermal sensation, hospital acquired pneumonia, and apraxia of speech. We hypothesized that some of these results reflect the fact that: (1) ischemic strokes that involve the insula are larger than strokes that exclude the insula (and therefore are associated with more common and persistent deficits); and (2) insular involvement is a marker of middle cerebral artery (MCA) occlusion. We analyzed MRI scans of 861 patients with acute ischemic hemispheric strokes unselected for functional deficits, and compared infarcts involving the insula to infarcts not involving the insula using t-tests for continuous variables and chi square tests for dichotomous variables. Mean infarct volume was larger for infarcts including the insula (n = 232) versus excluding the insula (n = 629): 65.8 ± 78.8 versus 10.2 ± 15.9 cm3 (p, Highlights • The insula is the most commonly infarcted area in patients with a wide range of deficits. • In 861 acute ischemic hemispheric strokes, mean infarct volume was much larger when infarct included the insula (p

We evaluated the hypothesis that Brodmann's area (BA) 37 within left occipitotemporal cortex has at least two important functions in lexical processing. One role is the computation of case-, font-, location-, and orientation-independent grapheme descriptions for written word recognition and production (reading and spelling). This role may depend on the medial part of BA 37, in left midfusiform gyrus. The second role is in accessing modality-independent lexical representations for output, for naming and for reading and spelling of irregular or exception words. This role may depend on the lateral part of BA 37 in inferior temporal cortex. We tested these hypotheses in 234 participants with acute left hemisphere ischaemic stroke who underwent magnetic resonance imaging (MRI) and language testing within 48 hours of onset of stroke symptoms.

Objective To evaluate language deficits after acute stroke and their association with post–acute care at a setting other than home. We hypothesized that deficits in language comprehension would be associated with discharge to a setting other than home after adjustment for physical/occupational therapy (PT/OT) needs. Design Secondary analysis of prospectively collected data. Discharge location, demographic characteristics (age, sex, race), and the presence of PT/OT recommendations were abstracted from the medical record. Setting Acute stroke unit at a tertiary medical center. Participants Left hemispheric stroke patients (N=152) within 24 hours of event. Interventions The following tasks were administered: (a–b) oral and written naming of pictured objects, (c) oral naming with tactile input (tactile naming), (d–f) oral reading, oral spelling, and repetition of words and pseudowords, (g) written spelling to dictation, (h) spoken word-picture verification (ie, auditory comprehension), and (i) written word-picture verification (ie, written word comprehension). Main Outcome Measure Discharge to a setting other than home. Results Of 152 cases, 88 were discharged home and 64 to another setting. Among stroke subjects discharged to a setting other than home, 63.6% had auditory comprehension deficits compared with 42.9% of those discharged home ( P =.03). Deficits in auditory and reading comprehension and oral spelling to dictation were significantly associated with increased odds of discharge to a setting other than home after adjustment for age and PT/OT recommendations. Conclusions Cases with deficits in auditory comprehension, reading comprehension, and oral spelling to dictation had increased odds of being discharged to settings other than home. Early evaluation of these language deficits and prompt treatment may allow patients who would otherwise be discharged to an institution to go home. Further research is needed to design and evaluate individualized treatment protocols and their effect on discharge recommendations.

Gonzalez-Fernandez M, Davis C, Molitoris JJ, Newhart M, Leigh R, Hillis AE. Formal education, socioeconomic status, and the severity of aphasia after stroke. Objective To determine the role of education and socioeconomic status on the severity of aphasia after stroke. Design Cross-sectional study. Setting Stroke units of 2 affiliated medical centers. Participants Stroke patients (n=173) within 24 hours of symptom development and hospitalized controls (n=62) matched for age, education, and socioeconomic status (SES) with normative brain magnetic resonance imaging. Interventions Not applicable. Main Outcome Measures Percent error on 9 language tasks (auditory and written comprehension, naming [oral, written, and tactile], oral reading, oral spelling, written spelling, and repetition). Education was recorded in years and dichotomized as less than 12 years or 12 years and above for data analysis. Demographic characteristics (age, sex, race) and stroke volume were recorded for adjustment. SES was obtained from census tract data as 2 variables: mean neighborhood household income and family income. Results The percentage of errors for participants with 12 or more years of education was significantly lower for auditory and written comprehension, written naming, oral reading, oral spelling, and written spelling of fifth grade vocabulary words, even after adjusting for age, sex, stroke volume, and SES. Conclusions These findings suggest that even once learned, access to written word forms may become less vulnerable to disruption by stroke with increasing years of education.

Introduction The objective of this study is to determine which cognitive processes underlying spelling are most affected in the three variants of primary progressive aphasia (PPA): Logopenic variant primary progressive aphasia (lvPPA), Semantic variant primary progressive aphasia (svPPA), and Nonfluent variant primary progressive aphasia (nfvPPA). Methods 23 PPA patients were administered The Johns Hopkins Dysgraphia Battery to assess spelling. Subtests evaluate for effects of word frequency, concreteness, word length, grammatical word class, lexicality (words vs pseudowords), and “regularity” by controlling for the other variables. Significant effects of each variable were identified with chi square tests. Responses on all spelling to dictation tests were scored by error type. 16 of the 23 subjects also had a high resolution MRI brain scan to identify areas of atrophy. Results We identified 4 patterns of spelling that could be explained by damage to one or more cognitive processes underlying spelling. Nine patients (3 unclassifiable, 4 with lvPPA, 2 with svPPA) had dysgraphia explicable by impaired access to lexical representations, with reliance on sublexical phonology-to-orthography conversion (POC). Two patients (with nfvPPA) showed dysgraphia explicable by impaired access to lexical representations and complete disruption of sublexical POC. Seven patients (4 with lvPPA, 1 with svPPA, 2 unclassifiable) showed dysgraphia explicable by impaired access to lexical-semantic representations and/or lexical representations with partially spared sublexical POC mechanisms. Five patients (1 with nfvPPA, 2 with svPPA, 1 with lvPPA, and 1 unclassifiable) showed dysgraphia explicable by impairment of the graphemic buffer. Conclusions Any cognitive process underlying spelling can be affected in PPA. Predominance of phonologically plausible errors, more accurate spelling of regular words than irregular words, and more accurate spelling of pseudowords than words (indicating spared POC mechanisms) may indicate a low probability of progression to nfvPPA.

Accumulating evidence indicates action naming may rely more on frontal-subcortical circuits, and noun naming may rely more on temporal cortex. Therefore, noun versus action fluency might distinguish frontal and subcortical dementias from cortical dementias primarily affecting temporal and/or parietal cortex such as Alzheimer’s disease (AD). We hypothesized patients with subcortical dementia, e.g., normal pressure hydrocephalus (NPH) and patients with dementias predominantly affecting frontal cortex, e.g., behavioral variant frontotemporal dementia (bv-FTD) and progressive nonfluent aphasia (PNFA) have more difficulty on action fluency versus noun fluency (e.g., animal naming). Patients with AD, who have temporo parietal cortical dysfunction, should have more difficulty on noun versus verb fluency. A total of 234 participants, including healthy controls (n = 20) and patients diagnosed with NPH (n =144), AD (n = 33), bv-FTD (n = 22) or PNFA (n = 15) were administered animal fluency, action fluency, and letter fluency tasks, and the Mini-Mental State Examination (MMSE, to control for dementia severity). NPH and bv-FTD/PNFA patients had significantly higher MMSE scores and animal fluency than AD patients (after adjusting for age), but their action fluency tended to be lower than in AD. Only NPH and bvFTD/PNFA patients showed significantly lower action verb than animal fluency. Results provide novel evidence that action naming relies more on frontal-subcortical circuits while noun naming relies more on temporoparietal cortex, indicating action verb fluency may be more sensitive than noun fluency, particularly for detecting frontal-subcortical dysfunction.

Background and Purpose— Hemispatial neglect is among the most common and disabling consequences of right hemisphere stroke. A variety of variables have been associated with the presence or severity of neglect but have not evaluated the independent effects of location, severity, and volume of ischemia. Few have determined areas involved in different types of neglect. We identified the contributions of these variables to severity of viewer-centered versus stimulus-centered neglect in acute ischemic right hemisphere stroke. Methods— We studied 137 patients within 24 hours of stroke onset with MR diffusion- and perfusion-weighted imaging and a test of hemispatial neglect that distinguishes between viewer-centered and stimulus-centered neglect. Using multivariable linear regression, we identified the independent contributions of severity of ischemia in specific locations, volume of ischemia, and age in accounting for severity of each neglect type. Results— Severity of hypoperfusion in angular gyrus was the only variable that significantly and independently contributed to severity of viewer-centered neglect. Volume of dysfunctional tissue and hypoperfusion in posterior frontal cortex also accounted for some variability in severity of viewer-centered neglect. Severity of hypoperfusion of superior temporal cortex was the only variable that independently and significantly contributed to severity of stimulus-centered neglect. Conclusions— Location, severity, and volume of ischemia together determine the type and severity of neglect after right hemisphere stroke. Results also show that perfusion-weighted MRI can be used as a semiquantitative measure of tissue dysfunction in acute stroke and can account for a substantial proportion of the variability in functional deficits in the acute stage.

There is evidence for different levels of visuospatial processing with their own frames of reference: viewer-centered, stimulus-centered, and object-centered. The neural locus of these levels can be explored by examining lesion location in subjects with unilateral spatial neglect (USN) manifest in these reference frames. Most studies regarding the neural locus of USN have treated it as a homogenous syndrome, resulting in conflicting results. In order to further explore the neural locus of visuospatial processes differentiated by frame of reference, we presented a battery of tests to 171 subjects within 48 hr after right supratentorial ischemic stroke before possible structural and/or functional reorganization. The battery included MR perfusion weighted imaging (which shows hypoperfused regions that may be dysfunctional), diffusion weighted imaging (which reveals areas of infarct or dense ischemia shortly after stroke onset), and tests designed to disambiguate between various types of neglect. Results were consistent with a dorsal/ventral stream distinction in egocentric/allocentric processing. We provide evidence that portions of the dorsal stream of visual processing, including the right supramarginal gyrus, are involved in spatial encoding in egocentric coordinates, whereas parts of the ventral stream (including the posterior inferior temporal gyrus) are involved in allocentric encoding.

Background: Primary progressive aphasia (PPA) refers to a progressive and selective decline in language due to neurodegenerative disease. There are three variants of PPA, progressive nonfluent aphasia (PNFA), semantic dementia (SD), and logopaenic progressive aphasia (LPA). All variants include impaired object naming, but distinct underlying deficits might interfere with naming. Therefore, individuals with different types of PPA may respond differently to naming therapy. Aims: To identify differences in patterns of success and generalisation in response to the same treatment in patient with LPA and a patient with SD. Furthermore, we wished to identify whether the treatment effect was item specific (trained words) or generalised to untrained words in trained or untrained categories. Methods & Procedures: Participants included an individual with LPA and one with SD. An assessment of lexical processing was administered before and after a naming treatment to assess underlying deficits and generalisation effec...

Background Semantic errors result from the disruption of access either to semantics or to lexical representations. One way to determine the origins of these errors is to evaluate comprehension of words that elicit semantic errors in naming. We hypothesized that in acute stroke there are different brain regions where dysfunction results in semantic errors in both naming and comprehension versus those with semantic errors in oral naming alone. Methods A consecutive series of 196 patients with acute left hemispheric stroke who met inclusion criteria were evaluated with oral naming and spoken word/picture verification tasks and magnetic resonance imaging within 48 h of stroke onset. We evaluated the relationship between tissue dysfunction in 10 pre-specified Brodmann's areas (BA) and the production of coordinate semantic errors resulting from (1) semantic deficits or (2) lexical access deficits. Results Semantic errors arising from semantic deficits were most associated with tissue dysfunction/infarct of left BA 22. Semantic errors resulting from lexical access deficits were associated with hypoperfusion/infarct of left BA 37. Conclusion Our study shows that semantic errors arising from damage to distinct cognitive processes reflect dysfunction of different brain regions.

Introduction: Unilateral neglect after acute right hemispheric stroke significantly impedes poststroke recovery. We studied patients with right hemispheric stroke to determine whether increasing age was associated with more frequent or more severe neglect. Methods: Eight neglect tests within 5 days of symptom onset (and within 24 hours of admission) were administered to 204 subjects with acute right hemispheric stroke. Size of infarct was measured, and neglect tests were scored as percent error. “Any neglect” was defined by an elevated neglect test score, standardized relative to a group of normal controls. Results: When tested for neglect soon after acute stroke admission, 69.6% of subjects older than 65 years had “any neglect” (defined by comparison to a group of normal controls), compared with 49.4% of subjects aged 65 years and younger ( p = 0.008). For every additional 10 years of age, patients were 1.83 times as likely to have neglect, even after adjusting for diffusion-weighted imaging (DWI) infarct volume and NIH Stroke Scale (NIHSS) score (95% CI 1.38–2.43). In addition, DWI volume and NIHSS independently predicted neglect. Score on virtually all of the neglect tests worsened as an effect of age. Percentage error on a line cancellation task was 3.8% higher for every additional 10 years of age, after adjustment for DWI volume and NIHSS ( p = 0.006). Similar results were found for other neglect tests. Conclusions: Increasing age in patients with acute right hemispheric stroke significantly increases the odds of unilateral neglect as well as severity of neglect, independently of size of the stroke or NIH Stroke Scale score. The reason for this finding in older patients may be because they have more brain atrophy and may be less able to compensate for cerebral infarction, or because they tend to have more cardioembolic strokes, which may be more cortically based.

Hemispatial neglect is a common and disabling consequence of stroke. Previous reports examining the relationship between gender and the incidence of unilateral spatial neglect (USN) have included either a large numbers of patients with few neglect tests or small numbers of patients with multiple tests. To determine if USN was more common and/or severe in men or women, we examined a large group of patients (312 right-handed) within 24 hours of acute right hemisphere ischemic stroke. Multiple spatial neglect tasks were used to increase the sensitivity of neglect detection. No differences based upon gender were observed for the prevalence, severity, or a combined task measure of USN.

Specific phobias, including animal phobias, are the most common anxiety disorders, and have a strong innate and genetic component. Research on the neurobiology and environmental constraints of innate fear of predators in rodents may be useful in elucidating mechanisms of animal phobias in humans. The present article reviews research on innate fear in rats to trimethylthiazoline (TMT), an odor originally isolated from fox feces. TMT induces unconditioned freezing and other defensive responses that are regulated by the dose of TMT and the shape of the testing environment. Contextual conditioning induced by TMT occurs, but is constrained by the environment. Lesion studies indicate the amygdala circuitry subserving fear conditioning is not necessary for unconditioned fear to TMT. Additionally, a medial hypothalamic defensive circuit also appears not necessary for unconditioned freezing to TMT, whereas circuits that include the medial nucleus of the amygdala and the bed nucleus of the stria terminalis are essential. The importance of these findings of innate predator odor fear in rodents to animal phobias in humans is discussed.

Background and Purpose: Diffusion–perfusion mismatch has been used to estimate salvageable tissue and predict potential for recovery in acute stroke. Location of the salvageable tissue may be as important as volume or percentage in predicting potential for recovery of specific functions. Impaired naming, a common and disabling deficit after left hemisphere stroke, is often associated with tissue dysfunction of left Brodmann area (BA) 37, posterior inferior temporal cortex. We tested the hypothesis that the presence of diffusion–perfusion mismatch within left BA 37 predicts probability and extent of short-term improvement of naming. Methods: One hundred five patients with acute left hemisphere ischemic stroke had diffusion-weighted imaging, perfusion-weighted imaging, a test of picture naming, and other language tests at admission and 2 to 4 days later. Linear regression was used to determine whether diffusion–perfusion mismatch in any BA in language cortex, total volume of mismatch, or diffusion or perfusion abnormality predicted degree of improvement in naming by days 3 to 5. Results: The presence of >20% diffusion–perfusion mismatch in left BA 37 and total volumes of diffusion and perfusion abnormality at day 1 each independently predicted degree of improvement in naming. Mismatch in this area did not predict the degree of improvement in other language tests or the NIH Stroke Scale in this study. Conclusions/Relevance: Diffusion–perfusion mismatch in left Brodmann area 37 was strongly associated with acute improvement in naming, independently of volume or percentage of total mismatch or diffusion or perfusion abnormality. These data indicate that mismatch in a particular area is a marker of salvageable tissue and an important predictor of potential for recovery of functions that depend on that area. Location of mismatch before treatment may help to predict potential benefits of reperfusion. GLOSSARY: ADC = apparent diffusion coefficient; BA = Brodmann area; DWI = diffusion-weighted imaging; NIHSS = NIH Stroke Scale; PWI = perfusion-weighted imaging; TE = echo time; TR = repetition time; TTP = time to peak.

A number of previous studies have indicated that Broca's area has an important role in understanding and producing syntactically complex sentences and other language functions. If Broca's area is critical for these functions, then either infarction of Broca's area or temporary hypoperfusion within this region should cause impairment of these functions, at least while the neural tissue is dysfunctional. The opportunity to identify the language functions that depend on Broca's area in a particular individual was provided by a patient with hyperacute stroke who showed selective hypoperfusion, with minimal infarct, in Broca's area, and acutely impaired production of grammatical sentences, comprehension of semantically reversible (but not non-reversible) sentences, spelling, and motor planning of speech articulation. When blood flow was restored to Broca's area, as demonstrated by repeat perfusion weighted imaging, he showed immediate recovery of these language functions. The identification of language functions that were impaired when Broca's area was dysfunctional (due to low blood flow) and recovered when Broca's area was functional again, provides evidence for the critical role of Broca's area in these language functions, at least in this individual.

Objective To identify dysfunctional brain regions critical for impaired reading/spelling of words/pseudowords by evaluating acute stroke patients on lexical tests and magnetic resonance imaging, before recovery or reorganization of structure–function relationships. Methods A series of 106 consenting patients were administered oral reading and spelling tests within 24 hours of left supratentorial stroke onset. Patients underwent diffusion- and perfusion-weighted magnetic resonance examination the same day to identify regions of hypoperfusion/infarct of 16 Brodmann areas. Results Simultaneous logistic regression analysis demonstrated that dysfunction of left Brodmann areas 40 (supramarginal gyrus) and 37 (posterior-inferior temporal/fusiform gyrus) best predicted impairment in reading words (odds ratio [OR], 6.20 [95% confidence interval (CI), 1.54–24.96] and 2.71 [95% CI, 0.87–8.45], respectively), reading pseudowords (OR, 39.65 [95% CI 3.9–400.78] and 4.41 [95% CI, 1.1–17.51], respectively), spelling words (OR, 14.11 [95% CI 1.37–144.93] and 7.41 [95% CI, 1.48–37.24], respectively), and spelling pseudowords (OR, 4.84 [95% CI, 0.73–32.13] and 7.74 [95% CI, 1.56–38.51], respectively). Whole-brain voxel-wise analyses demonstrated voxel clusters within these regions that were most strongly associated with task deficits. Interpretation Results indicate that a shared network of regions including parts of left Brodmann areas 37 and 40 is necessary for reading and spelling of words and pseudowords. Further studies may define the precise roles of these brain regions in language. Identification of any neural regions specific to one of these tasks or one type of stimuli will require study of more patients with selective deficits. Ann Neurol 2007

The frequency of various types of unilateral spatial neglect and associated areas of neural dysfunction after left hemisphere stroke are not well characterized. Unilateral spatial neglect (USN) in distinct spatial reference frames have been identified after acute right, but not left hemisphere stroke. We studied 47 consecutive right handed patients within 48 hours of left hemisphere stroke to determine the frequency and distribution of types of right USN using cognitive testing and MRI imaging. The distribution of USN types was different from the previously reported distribution following acute right hemisphere stroke. In this left hemisphere stroke population, allocentric neglect was more frequent than egocentric neglect.

We hypothesized that distinct cognitive processes underlying oral and written picture naming depend on intact function of different, but overlapping, regions of the left hemisphere cortex, such that the distribution of tissue dysfunction in various areas can predict the component of the naming process that is disrupted. To test this hypothesis, we evaluated 116 individuals within 24 h of acute ischaemic stroke using a battery of oral and written naming and other lexical tests, and with magnetic resonance diffusion and perfusion imaging to identify the areas of tissue dysfunction. Discriminant function analysis, using the degree of hypoperfusion in various Brodmann's areas--BA 22 (including Wernicke's area), BA 44 (part of Broca's area), BA 45 (part of Broca's area), BA 21 (inferior temporal cortex), BA 37 (posterior, inferior temporal/fusiform gyrus), BA 38 (anterior temporal cortex) and BA 39 (angular gyrus)--as discriminant variables, classified patients on the basis of the primary component of the naming process that was impaired (defined as visual, semantics, modality-independent lexical access, phonological word form, orthographic word form and motor speech by the pattern of performance and types of errors across lexical tasks). Additionally, linear regression analysis demonstrated that the areas contributing the most information to the identification of patients with particular levels of impairment in the naming process were largely consistent with evidence for the roles of these regions from functional imaging. This study provides evidence that the level of impairment in the naming process reflects the distribution of tissue dysfunction in particular regions of the left anterior, inferior and posterior middle/superior temporal cortex, posterior inferior frontal and inferior parietal cortex. While occipital cortex is also critical for picture naming, it is likely that bilateral occipital damage is necessary to disrupt visual recognition. These findings provide new evidence that a network of brain regions supports naming, but separate components of this network are differentially required for distinct cognitive processes or representations underlying the complex task of naming pictures.

Background and Purpose— The National Institutes of Health Stroke Scale (NIHSS) includes minimal assessment of cognitive function, particularly in right hemisphere (RH) stroke. Descriptions of the Cookie Theft picture from the NIHSS allow analyses that (1) correlate with aphasia severity and (2) identify communication deficits in RH stroke. We hypothesized that analysis of the picture description contributes valuable information about volume and location of acute stroke. Methods— We evaluated 67 patients with acute ischemic stroke (34 left hemisphere [LH]; 33 RH) with the NIHSS, analysis of the Cookie Theft picture, and magnetic resonance imaging, compared with 35 sex- and age-matched controls. We evaluated descriptions for total content units (CU), syllables, ratio of left:right CU, CU/minute, and percent interpretive CU, based on previous studies. Lesion volume and percent damage to regions of interest were measured on diffusion-weighted imaging. Multivariable linear regression identified variables associated with infarct volume, independently of NIHSS score, age and sex. Results— Patients with RH and LH stroke differed from controls, but not from each other, on CU, syllables/CU, and CU/minute. Left:right CU was lower in RH compared with LH stroke. CU, syllables/CU, and NIHSS each correlated with lesion volume in LH and RH stroke. Lesion volume was best accounted by a model that included CU, syllables/CU, NIHSS, left:right CU, percent interpretive CU, and age, in LH and RH stroke. Each discourse variable and NIHSS score were associated with percent damage to different regions of interest, independently of lesion volume and age. Conclusions— Brief picture description analysis complements NIHSS scores in predicting stroke volume and location.

Primary progressive aphasia (PPA) is a neurodegenerative disease that primarily affects language functions and often begins in the fifth or sixth decade of life. The devastating effects on work and family life call for the investigation of treatment alternatives. In this article, we present new data indicating that neuromodulatory treatment, using transcranial direct current stimulation (tDCS) combined with a spelling intervention, shows some promise for maintaining or even improving language, at least temporarily, in PPA.The main aim of the present article is to determine whether tDCS plus spelling intervention is more effective than spelling intervention alone in treating written language in PPA. We also asked whether the effects of tDCS are sustained longer than the effects of spelling intervention alone.We present data from six PPA participants who underwent anodal tDCS or sham plus spelling intervention in a within-subject crossover design. Each stimulation condition lasted 3 weeks or a total of 15 sessions with a 2-month interval in between. Participants were evaluated on treatment tasks as well as on other language and cognitive tasks at 2-week and 2-month follow-up intervals after each stimulation condition.All participants showed improvement in spelling (with sham or tDCS). There was no difference in the treated items between the two conditions. There was, however, consistent and significant improvement for untrained items only in the tDCS plus spelling intervention condition. Furthermore, the improvement lasted longer in the tDCS plus spelling intervention condition compared to sham plus spelling intervention condition.Neuromodulation with tDCS offers promise as a means of augmenting language therapy to improve written language function at least temporarily in PPA. The consistent finding of generalisation of treatment benefits to untreated items and the superior sustainability of treatment effects with tDCS justifies further investigations. However, the small sample size still requires caution in interpretation. Present interventions need to be optimised, and particular challenges, such as ways to account for the variable effect of degeneration in each individual, are discussed.

Introduction It is well known that right hemisphere ischemic stroke often results in hemispatial neglect. Recent studies have also shown that right hemisphere stroke may cause impairment in processing emotional prosody (tone of voice) as well. We tested the hypothesis that stroke patients are more accurately distinguished from neurologically intact controls by tests of emotional prosody comprehension than by tests of hemispatial neglect. Methods We tested a series of 29 patients (mean age - 55 years old and mean education - 14 years)within 48 hours of onset of first right hemisphere ischemic stroke and 23 hospitalized age- and education- matched controls with MRI, a prosody comprehension battery and a battery of hemispatial neglect tests (line cancellation, copying a scene, gap detection, line bisection) . Emotion categorization tasks assessed recognition of 6 emotion categories (happy, sad, angry, surprise, disinterest, neutral) from prosodic cues in 2 conditions with varying verbal demands (neutral sentences and monosyllables). We used Receiver Operating Characteristic curves to identify the scores that most accurately classified stroke patients versus controls, using summary scores for Prosody and Neglect based on all of subtests for each. Results The Prosody Score was more effective than the Neglect Score in distinguishing stroke patients from controls, as measured by a Receiver Operating Characteristic (AUC for Prosody Score = 0.86). An overall error rate of > 27% on the prosody comprehension battery had a sensitivity of 89.74% and specificity of 68.18% (correctly classifying 82.0% of participants as patients vs controls). In contrast, the AUC for Neglect Summary Score was 0.55. At most, the Neglect Score could classify 55.8% of patients vs. controls. Of 25 patients who made >27% errors on Prosody Comprehension, 22 (88%) made 0% errors on the Neglect battery. Conclusion Prosody impairment may be a better indicator of right cortical dysfunction than hemispatial neglect in acute stroke and may therefore be a better measure of effectiveness of interventions to salvage cortical function, such as reperfusion therapies.

Objective: Test the hypothesis that right hemisphere stroke can cause extinction of left hand movements or movements of either hand held in left space, when both are used simultaneously, possibly depending on lesion site. Methods: 93 non-hemiplegic patients with acute right hemisphere stroke were tested for motor extinction by pressing a counter rapidly for one minute with the right hand, left hand, or both simultaneously with their hands held at their sides, or crossed over midline. Results: We identified two distinct types of motor extinction in separate patients; 20 patients extinguished left hand movements held in left or right space (left canonical body extinction); the most significantly associated voxel cluster of ischemic tissue was in the right temporal white matter. Seven patients extinguished either hand held in left space (left space extinction), and the most significantly associated voxel cluster of ischemic tissue was in right parietal white matter. Conclusions: There was a double dissociation between left canonical body extinction and left space motor extinction. Left canonical body extinction seems to be associated with more dorsal (parietal) ischemia, and left canonical body extinction seems to be associated with more ventral (temporal) ischemia.

We report patterns of dysgraphia in participants with primary progressive aphasia that can be explained by assuming disruption of one or more cognitive processes or representations in the complex process of spelling. These patterns are compared to those described in participants with focal lesions (stroke). Using structural imaging techniques, we found that damage to the left extrasylvian regions, including the uncinate, inferior fronto-occipital fasciculus, and sagittal stratum (including geniculostriate pathway and inferior longitudinal fasciculus), as well as other deep white and grey matter structures, was significantly associated with impairments in access to orthographic word forms and semantics (with reliance on phonology-to-orthography to produce a plausible spelling in the spelling to dictation task). These results contribute not only to our understanding of the patterns of dysgraphia following acquired brain damage but also the neural substrates underlying spelling.

We evaluated sentence comprehension of variety of sentence constructions and components of short term memory in 53 individuals with acute ischemic stroke, to test some current hypotheses about the role of Broca's area in these tasks. We found that some patients show structure-specific, task-independent deficits in sentence comprehension, with chance level of accuracy on passive reversible sentences, more impaired comprehension of object-cleft than subject-cleft sentences, and more impaired comprehension of reversible than irreversible sentences in both sentence-picture matching and enactment tasks. In a dichotomous analysis, this pattern of “asyntactic comprehension” was associated with dysfunctional tissue in left angular gyrus, rather than dysfunctional tissue in Broca's area as previously proposed. Tissue dysfunction in left Brodmann area (BA) 44, part of Broca's area, was associated with phonological short term memory (STM) impairment defined by forward digit span ≤ 4. Verbal working memory defined by backward digit span ≤ 2 was associated with tissue dysfunction left premotor cortex (BA 6). In a continuous analysis, patients with acute ischemia in left BA 44 were impaired in phonological STM. Patients with ischemia in left BA 45 and BA 6 were impaired in passive, reversible sentences, STM, and verbal working memory. Patients with ischemia in left BA 39 were impaired in passive reversible sentences, object cleft sentences, STM, and verbal working memory. Therefore, various components of working memory seem to depend on a network of brain regions that include left angular gyrus and posterior frontal cortex (BA 6, 44, 45); left BA 45 and angular gyrus (BA 39) may have additional roles in comprehension of syntax such as thematic role checking.

Background: The National Institutes of Health Stroke Scale (NIHSS) has been criticized for limited representation of cognitive dysfunction and bias towards dominant hemisphere functions. Patients may therefore receive a low NIHSS score despite a fairly large stroke. A broader scale including simple cognitive tests would improve the clinical and research utility of the NIHSS. Methods: We studied 200 patients with acute non-dominant hemispheric stroke who underwent cognitive testing and had MRI with diffusion-weighted imaging (DWI) within 5 days of presentation. We measured DWI volumes and retrospectively calculated NIHSS scores. We used linear regression to determine the role of selected cognitive tests, when added to the NIHSS, in predicting DWI volume. Results: The NIHSS predicted DWI volume in a univariate analysis, as did total line cancellation and a visual perception task. In a multivariate model, using log-transformed variables, the NIHSS (p = 0.0002), line cancellation errors (p = 0.02) and visual perception (p = 0.004) each improved prediction of total infarct volume. Conclusion: The addition of line cancellation and visual perception tasks significantly adds to the model of NIHSS alone in predicting DWI volume. We propose that these two cognitive tests, which together can be completed in 2–3 minutes, could be combined with the NIHSS to create an “NIHSS-plus” that more accurately represents a patient’s ischemic tissue volume after a stroke. This scale requires further validation in a prospective study.

Background and Purpose— We aimed to determine if ischemia involving Broca area predicts Broca aphasia more reliably in acute or chronic stroke. Methods— We included consecutive right-hand-dominant patients with left hemisphere ischemic stroke (6 months after stroke for chronic stroke). MRI scans were analyzed for ischemic lesions or hypoperfusion in Broca area (Brodmann areas 44 and 45). Patients were scored on the Western Aphasia Battery to classify aphasia syndromes; χ 2 tests were used to identify significant associations. Results— The presence of infarct involving any part of Broca area and the presence of Broca or global aphasia was much stronger in acute (χ 2 =38.1; df 1; P 2 =0.54; df 1; P =0.46; not significant). The association between infarct or hypoperfusion covering all of Broca area and the presence of Broca or global aphasia was much stronger in acute (χ 2 =35.8; df 1; P 2 =1.2; df 1; p= 0.27; not significant). In a subset of 20 patients studied longitudinally, the associations were significant only acutely, not chronically (χ 2 =20; df 1; P 2 =0; df 1; p= 1; not significant for ischemia involving part of Broca area, and χ 2 =16.4; df 1; P 2 =3.2; df 1; p= 0.08; not significant for ischemia covering all of Broca area). Conclusions— Broca aphasia is more reliably associated with infarct/ hypoperfusion of Broca area in acute stroke. Many chronic stroke patients with damage to part or all of Broca area had neither Broca nor global aphasia. Broca or global aphasia was sometimes present initially in these patients but resolved by 6 months. Our results indicate that the acute aphasia syndrome may allow the clinician to predict the compromised vascular territory, even when structural imaging shows only a small (or no) infarct.

Oral reading is a complex skill involving the interaction of orthographic, phonological, and semantic processes. Functional imaging studies with non-impaired adult readers have identified a widely distributed network of frontal, inferior parietal, posterior temporal, and occipital brain regions involved in the task. However, while functional imaging can identify cortical regions engaged in the process under examination, it cannot identify those brain regions essential for the task. The current study aimed to identify those neuroanatomical regions critical for successful oral reading by examining the relationship between word and nonword oral reading deficits and areas of tissue dysfunction in acute stroke. We evaluated 91 patients with left hemisphere ischemic stroke with a test of oral word and nonword reading, and magnetic resonance diffusion-weighted and perfusion-weighted imaging, within 24–48 hours of stroke onset. A voxel-wise statistical map showed that impairments in word and nonword reading were associated with a distributed network of brain regions, including the inferior and middle frontal gyri, the middle temporal gyrus, the supramarginal and angular gyri, and the middle occipital gyrus. In addition, lesions associated with word deficits were found to be distributed more frontally, while nonword deficits were associated with lesions distributed more posteriorly.

We aimed to identify neuroanatomical regions associated with deficits to the graphemic buffer, a working memory component of the spelling system that holds the sequence of letter identities during production. We evaluated 331 patients with left hemisphere ischemic stroke with various spelling tests and magnetic resonance diffusion-weighted imaging and perfusion-weighted imaging, within 48 hours of stroke onset. A voxel-wise statistical map showed that ischemia in voxels in posterior and inferior frontal and parietal cortex, subcortical white matter underlying prefrontal cortex, lateral occipital gyrus, or caudate was associated with impairment in maintaining the sequence of letter identities while spelling.

Sites of lesions responsible for visual, tactile, and/or motor extinction have not been clearly identified. We sought to determine the frequency of extinction in various modalities immediately after acute ischemic stroke, the rate of co-occurrence of extinction across modalities, and areas of infarct and/or hypoperfusion associated with each modality of extinction. A total of 148 patients with right supratentorial stroke were studied. In Study 1, 88 patients without hemiplegia, hemianesthesia, or visual field cuts were tested within 24 hours of onset for visual, tactile, and motor extinction, and underwent magnetic resonance diffusion and perfusion imaging. Associations between modality of extinction and areas of neural dysfunction (hypoperfusion/infarct) were identified. Of the 88 patients, 19 had only tactile extinction, 8 had only visual extinction, 12 had only motor extinction, 14 had extinction in two or more modalities, and 35 had no extinction. Tactile extinction was associated with neural dysfunction in the inferior parietal lobule; visual extinction was associated with dysfunction in the visual association cortex; and motor extinction was associated with neural dysfunction in the superior temporal gyrus. In Study 2, data from 60 patients who were excluded from Study 1 because of motor deficits were analyzed in the same way to determine whether frontal lesions contributed to visual or tactile extinction. Results again demonstrated that tactile extinction is associated with inferior parietal dysfunction, and visual extinction is associated with dysfunction of the visual association cortex. Potential accounts of the results, based on the “hemisphere rivalry” model of extinction and the limited attentional capacity model, are considered.

Background A 67-year-old right-handed man with a history of atrial fibrillation developed sudden aphasia after urological surgery. Initial diffusion-weighted and perfusion-weighted MRI demonstrated an area of hypoperfusion in Broca's area, with minimal infarction. Investigations Neurological examination, language testing and brain MRI scans with diffusion-weighted and perfusion-weighted imaging. Diagnosis Acute cardioembolic stroke with minimal infarction in Broca's area and a surrounding region of potentially salvageable, hypoperfused cortex. Management Saline-induced hypertension resulting in rapid restoration of cortical perfusion and a resolution of the initial speech and language deficits. The utility of perfusion-weighted imaging in selecting appropriate candidates for urgent treatment of stroke when thrombolysis is contraindicated is discussed.