Performance of Individuals with Left-Hemisphere Stroke and Aphasia and Individuals with Right Brain Damage on Forward and Backward Digit Span Tasks

Using a combined working memory - Semantic feature analysis approach to treat anomia in aphasia: A Pilot Study

INTRODUCTION

The purpose of the study was to pilot a working memory (WM) - and modified Semantic Feature Analysis (SFA) approach to treat word finding deficits in a group of people with aphasia (PwA). Two research questions were posed: 1. Will the group of PwA be able to complete the WM tasks used in the approach? 2. Will the approach improve naming performance in PwA?

METHOD

Three individuals with mild - moderate aphasia participated in this singlesubject multiple baseline treatment design. Pre-treatment assessments of language, and pre- to post-treatment assessments of WM abilities were carried out. The treatment protocol incorporated WM and linguistic tasks in order to improve naming accuracy across two treatment lists. Probes were carried out prior to treatment on each list, and at one-month following completion of treatment. Two outcome measures were obtained: Percent accuracy in completing the WM steps, and treatment effect sizes (Beeson & Robey, 2006). Additionally, modified t-tests (Crawford & Garthwaite, 2012; Crawford & Howell, 1998), were calculated in which post-treatment WM measures were compared against neurotypical control groups to detect any improvements in WM functions.

RESULTS

All three participants completed the WM steps with a high degree of accuracy. A range of small to large ESs were obtained for all three participants across the two treated lists, while no meaningful ESs were obtained for the control (untreated) list. All three participants demonstrated improved scores across most of the WM measures with significant improvements noted on certain WM assessments.

CONCLUSIONS

The findings revealed that the WM - SFA approach can be used successfully in individuals with mild - moderate aphasia. The proposed approach holds promise as feasible intervention designed to remediate anomia in PwA.

The right uncinate fasciculus supports verbal short-term memory in aphasia

Verbal short-term memory (STM) deficits are associated with language processing impairments in people with aphasia. Importantly, the integrity of STM can predict word learning ability and anomia therapy gains in aphasia. While the recruitment of perilesional and contralesional homologous brain regions has been proposed as a possible mechanism for aphasia recovery, little is known about the white-matter pathways that support verbal STM in post-stroke aphasia. Here, we investigated the relationships between the language-related white matter tracts and verbal STM ability in aphasia. Nineteen participants with post-stroke chronic aphasia completed a subset of verbal STM subtests of the TALSA battery including nonword repetition (phonological STM), pointing span (lexical-semantic STM without language output) and repetition span tasks (lexical-semantic STM with language output). Using a manual deterministic tractography approach, we investigated the micro- and macrostructural properties of the structural language network. Next, we assessed the relationships between individually extracted tract values and verbal STM scores. We found significant correlations between volume measures of the right Uncinate Fasciculus and all three verbal STM scores, with the association between the right UF volume and nonword repetition being the strongest one. These findings suggest that the integrity of the right UF is associated with phonological and lexical-semantic verbal STM ability in aphasia and highlight the potential compensatory role of right-sided ventral white matter language tracts in supporting verbal STM after aphasia-inducing left hemisphere insult.

Which blueberries are better value? The development and validation of the functional numeracy assessment for adults with aphasia

BACKGROUND

People with aphasia (PWA) can experience functional numeracy difficulties, that is, problems understanding or using numbers in everyday life, which can have numerous negative impacts on their daily lives. There is growing interest in designing functional numeracy interventions for PWA; however, there are limited suitable assessments available to monitor the impact of these interventions. Existing functional numeracy assessments lack breadth and are not designed to be accessible for PWA, potentially confounding their performance. Additionally, they do not include real-life demands, such as time pressure, which may affect their ecological validity. Thus, there is a crucial need for a new assessment to facilitate further research of PWA's functional numeracy.

AIMS

To develop, validate and pilot a wide-ranging, aphasia-friendly functional numeracy assessment to investigate how functional numeracy is impacted by aphasia severity and time pressure demands, and to explore predictors of PWA's functional numeracy.

METHODS & PROCEDURES

To develop the Functional Numeracy Assessment (FNA), 38 items inspired by the General Health Numeracy Test (GHNT) and Excellence Gateway were adapted for suitability for PWA and entered in a computerized psychometric-style test. The final 23 items (FNA23) were selected based on 213 neurotypical controls' performance, and controlled for difficulty, response modality and required numeracy skills. Aphasia-friendly adaptations of the GHNT and Subjective Numeracy Scale were used to examine the FNA23's concurrent validity. Internal consistency reliability and interrater reliability (for spoken responses) were also examined. A novel Time Pressure Task was created by slight adaptation of seven FNA23 questions to explore the effects of time pressure on functional numeracy performance. A total of 20 PWA and 102 controls completed all measures on an online testing platform.

OUTCOMES & RESULTS

The FNA23 demonstrated acceptable internal consistency reliability (KR-20 = 0.81) and perfect interrater reliability (for spoken responses). FNA23 and GHNT scores were positively associated, suggesting satisfactory concurrent validity. PWA demonstrated poorer functional numeracy than controls and took longer to complete assessments, indicating that aphasia impacts functional numeracy. Time pressure did not significantly impact performance. PWA demonstrated a wide range of functional numeracy abilities, with some performing similarly to controls.

CONCLUSIONS & IMPLICATIONS

The FNA23 is a wide-ranging, valid and reliable assessment which, with further development, will be a useful tool to identify and monitor PWA's functional numeracy difficulties in research and clinical practice. Considering PWA's widespread functional numeracy difficulties evidenced by this study, all PWA would likely benefit from routine evaluation for functional numeracy difficulties as part of their neurorehabilitation journeys.

WHAT THIS PAPER ADDS

What is already known on this subject Few studies have investigated functional numeracy difficulties in PWA. No published functional numeracy assessments exist that have been specifically designed to be accessible for PWA. What this paper adds to existing knowledge The newly developed FNA23 is a valid and reliable tool to extensively assess PWA's functional numeracy. This study confirmed previous findings of widespread functional numeracy difficulties in PWA that are related to their aphasia severity. What are the potential or actual clinical implications of this work? The FNA23 can be used to assess PWA's functional numeracy to inform areas of strengths and difficulties to target in intervention, and to monitor progress towards achieving intervention objectives. All PWA should be routinely evaluated for functional numeracy difficulties.

Sulcal depth in prefrontal cortex: a novel predictor of working memory performance

The neuroanatomical changes that underpin cognitive development are of major interest in neuroscience. Of the many aspects of neuroanatomy to consider, tertiary sulci are particularly attractive as they emerge last in gestation, show a protracted development after birth, and are either human- or hominoid-specific. Thus, they are ideal targets for exploring morphological-cognitive relationships with cognitive skills that also show protracted development such as working memory (WM). Yet, the relationship between sulcal morphology and WM is unknown-either in development or more generally. To fill this gap, we adopted a data-driven approach with cross-validation to examine the relationship between sulcal depth in lateral prefrontal cortex (LPFC) and verbal WM in 60 children and adolescents between ages 6 and 18. These analyses identified 9 left, and no right, LPFC sulci (of which 7 were tertiary) whose depth predicted verbal WM performance above and beyond the effect of age. Most of these sulci are located within and around contours of previously proposed functional parcellations of LPFC. This sulcal depth model outperformed models with age or cortical thickness. Together, these findings build empirical support for a classic theory that tertiary sulci serve as landmarks in association cortices that contribute to late-maturing human cognitive abilities.

Extra-Linguistic Cognitive Functions Involved in the Token Test: Results from a Cohort of Non-Aphasic Stroke Patients with Right Hemisphere Lesion

BACKGROUND

The Token Test (TT) is widely used to examine comprehension disorders in aphasic patients, but abilities other than language may affect a patient's performance. This study aims to explore the correlation between the TT subtest performances and the performances in extra-linguistic cognitive areas in a cohort of patients from the Intensive Rehabilitation Post-Stroke (RIPS) study with a first, right hemisphere stroke and without aphasia, prospectively enrolled at admission to intensive inpatient post-acute rehabilitation.

METHODS

The patients were administered the TT (50-item version), the forward and backward digit span (DST), and the Montreal Cognitive Assessment (MoCA). Spearman's partial correlations adjusted by age were used to evaluate the association between the number of errors in the TT and the other tests' corrected scores.

RESULTS

Of the 37 patients enrolled in this study, 29.7% made 3-11 errors on the TT, 27.0% more than 11 errors, mostly in parts IV and V. The forward and backward digit span scores showed correlations with errors in part V of the TT (r = -0.408, p = 0.013; r = -0.307, p = 0.027). The errors in part IV of the TT presented a correlation with a forward digit span too (r = -0.394, p = 0.017). With respect to MoCA domains, executive functioning, and orientation were related to the TT part V errors (r = -0.468, p = 0.007; r = -0.499, p = 0.003). The orientation also correlated with the TT part III (r = -0.504, p = 0.002).

CONCLUSION

Our findings show that the TT performances in patients with right hemisphere stroke and without aphasia are related to impairments in auditory-verbal span/auditory working memory mostly for TT scores on subpart V as measured by the DST and to executive function and orientation, as measured by the MoCA subtests.

Short-term memory and sentence comprehension in Catalan aphasia

The main goal of the present study is to investigate visual and verbal short-term memory side to side with sentence comprehension in Catalan-speaking subjects with aphasia in comparison with subjects without brain damage. We aim to examine whether there are any significant correlations between their performance on short-term memory and comprehension tasks in order to evaluate the hypothesis that linguistic and memory deficits in aphasia are the result of a dysfunction of a common mechanism, usually short-term memory. Eigthy-four control subjects and twelve individuals suffering from different types of aphasia were assessed using the Catalan version of the Comprehensive Aphasia Test (CAT-CAT), which includes one recognition task and two digit and word span tests to evaluate visual and verbal short-term memory, respectively, as well as a sentence-to-picture comprehension task. The results showed that the performance of subjects with aphasia was significantly low on all tasks. Yet, the logistic regression analysis revealed that the magnitude of the differences between the control and experimental group varied across subtests, and that visual short-term memory was better preserved than verbal memory. The results also showed that there were no significant correlations between memory and language comprehension, which rules out the hypothesis that the deficits observed are due to a common underlying mechanism. Individual variation was also observed, specially on memory subtests, which suggest that memory impairments cannot explain the comprehension deficit in aphasia.

Common Neuroanatomical Substrate of Cholinergic Pathways and Language-Related Brain Regions as an Explanatory Framework for Evaluating the Efficacy of Cholinergic Pharmacotherapy in Post-Stroke Aphasia: A Review

Despite the relative scarcity of studies focusing on pharmacotherapy in aphasia, there is evidence in the literature indicating that remediation of language disorders via pharmaceutical agents could be a promising aphasia treatment option. Among the various agents used to treat chronic aphasic deficits, cholinergic drugs have provided meaningful results. In the current review, we focused on published reports investigating the impact of acetylcholine on language and other cognitive disturbances. It has been suggested that acetylcholine plays an important role in neuroplasticity and is related to several aspects of cognition, such as memory and attention. Moreover, cholinergic input is diffused to a wide network of cortical areas, which have been associated with language sub-processes. This could be a possible explanation for the positive reported outcomes of cholinergic drugs in aphasia recovery, and specifically in distinct language processes, such as naming and comprehension, as well as overall communication competence. However, evidence with regard to functional alterations in specific brain areas after pharmacotherapy is rather limited. Finally, despite the positive results derived from the relevant studies, cholinergic pharmacotherapy treatment in post-stroke aphasia has not been widely implemented. The present review aims to provide an overview of the existing literature in the common neuroanatomical substrate of cholinergic pathways and language related brain areas as a framework for interpreting the efficacy of cholinergic pharmacotherapy interventions in post-stroke aphasia, following an integrated approach by converging evidence from neuroanatomy, neurophysiology, and neuropsychology.

Does Early Exposure to Chinese-English Biliteracy Enhance Cognitive Skills?

Clarifying the effects of biliteracy on cognitive development is important to understanding the role of cognitive development in L2 learning. A substantial body of research has shed light on the cognitive factors contributing to biliteracy development. Yet, not much is known about the effect of the degree of exposure to biliteracy on cognitive functions. To fill this research void, we measured three categories of biliteracy skills (language, reading, and cognitive-linguistic skills in both Chinese and English) jointly and investigated the effects of biliteracy skill performance in these three categories on cognitive skills (working memory and attentional control) in Chinese L1 children who were exposed to English as L2 beginning at age 3 ("early") or in grade 3 ("late"). In this cross-sectional study, 10 parallel Chinese and English language, reading, and cognitive-linguistic measures were administered to emerging Chinese-English bilingual children in grade 3 (n = 178) and grade 6 (n = 176). The results revealed that early exposure to Chinese-English biliteracy enhanced cognitive skills but with a cost of a slight delay in performance on Chinese L1 language skills in grade 3 (but not in grade 6). Importantly, the present findings suggest that, in addition to universal and developmental processes, the cumulative effect of early and sustained bi-scriptal exposure enhances working memory and attention in school children.

Effect of 3-Month Aerobic Dance on Hippocampal Volume and Cognition in Elderly People With Amnestic Mild Cognitive Impairment: A Randomized Controlled Trial

As an intermediate state between normal aging and dementia, mild cognitive impairment (MCI), especially amnestic MCI (aMCI), is a key stage in the prevention and intervention of Alzheimer’s disease (AD). Whether dancing could increase the hippocampal volume of seniors with aMCI remains debatable. The aim of this study was to investigate the influence of aerobic dance on hippocampal volume and cognition after 3 months of aerobic dance in older adults with aMCI. In this randomized controlled trial, 68 elderly people with aMCI were randomized to either the aerobic dance group or the control group using a 1:1 allocation ratio. Ultimately, 62 of 68 participants completed this study, and the MRI data of 54 participants were included. A specially designed aerobic dance routine was performed by the dance group three times per week for 3 months, and all participants received monthly healthcare education after inclusion. MRI with a 3.0T MRI scanner and cognitive assessments were performed before and after intervention. High-resolution three-dimensional (3D) T1-weighted anatomical images were acquired for the analysis of hippocampal volume. A total of 35 participants (mean age: 71.51 ± 6.62 years) were randomized into the aerobic dance group and 33 participants (mean age: 69.82 ± 7.74 years) into the control group. A multiple linear regression model was used to detect the association between intervention and the difference of hippocampal volumes as well as the change of cognitive scores at baseline and after 3 months. The intervention group showed greater right hippocampal volume (β [95% CI]: 0.379 [0.117, 0.488], p = 0.002) and total hippocampal volume (β [95% CI]: 0.344 [0.082, 0.446], p = 0.005) compared to the control group. No significant association of age or gender was found with unilateral or global hippocampal volume. There was a correlation between episodic memory and intervention, as the intervention group showed a higher Wechsler Memory Scale-Revised Logical Memory (WMS-RLM) score (β [95% CI]: 0.326 [1.005, 6.773], p = 0.009). Furthermore, an increase in age may cause a decrease in the Mini-Mental State Examination (MMSE) score (β [95% CI]: −0.366 [−0.151, −0.034], p = 0.002). In conclusion, 3 months of aerobic dance could increase the right and total hippocampal volumes and improve episodic memory in elderly persons with aMCI.

Clinical Trial Registration: This study was registered on the Chinese Clinical Trial Registry [www.chictr.org.cn], identifier [ChiCTR-INR-15007420].

Ethical considerations in the management of poststroke aphasia

From the onset of the first signs of stroke, patients are faced with a chain of events that requires quick decision-making to ensure that lifesaving care is administered. Considering that acute stroke is often associated with altered mental status and changes in cognitive-linguistic abilities, ethical dilemmas may arise when patients are unable to provide input in their own care and must rely on surrogate decision-makers to act on their behalf. Although the most critical, lifesaving decisions are made acutely, for the patients who go on to have residual chronic cognitive-linguistic deficits, loss of language, and/or impaired cognition may mean that a healthcare power of attorney or other proxy is needed to assist with medical decision-making. This chapter discusses ethical concerns surrounding the care of stroke survivors, with a focus on how poststroke cognitive-linguistic deficits can complicate this topic; clinical recommendations are provided.

Moving Toward Accurate Assessment of Working Memory in Adults With Neurogenically Based Communication Disorders

Purpose This article presents a viewpoint highlighting concerns regarding currently available assessments of working memory in adults with neurogenic communication disorders. Additionally, we provide recommendations for improving working memory assessment in this population. Method This viewpoint includes a critique of clinical and experimental working memory tests relevant to speech-language pathologists. We consider the terminology used to describe memory, as well as discuss language demands and test construction. Results Clinical and experimental testing of working memory in adults with neurogenic communication disorders is challenged due to theoretical, methodological, and practical limitations. The major limitations are characterized as linguistic and task demands, presentation and response modality effects, test administration, and scoring parameters. Taking these limitations into consideration, several modifications to working memory testing and their relevance to neurogenic populations are discussed. Conclusions The recommendations provided in this article can better guide clinicians and researchers to advocate for improved tests of working memory in adults with neurogenic communication disorders. Future research should continue to address these concerns and consider our recommendations.

Working Memory in Aphasia: The Role of Temporal Information Processing

Aphasia is an acquired impairment of language functions resulting from a brain lesion. It is usually accompanied by deficits in non-linguistic cognitive processes. This study aimed to investigate in patients with aphasia the complex interrelationships between selected cognitive functions: auditory speech comprehension, working memory (WM), and temporal information processing (TIP) in the millisecond time range. Thirty right-handed subjects (20 males) aged from 27 to 82 years suffering from post-stroke aphasia participated in the study. Verbal working memory (VWM) and spatial working memory (SWM) were assessed with: (1) a receptive verbal test and (2) the Corsi Block-Tapping Test, respectively. Both these WM tests used the forward tasks (mainly engaging maintenance processes, i.e., storing, monitoring, and matching information) and backward tasks (engaging both maintenance and manipulation processes, i.e., reordering and updating information). Auditory comprehension was assessed by receptive language tests, and TIP efficiency was assessed by auditory perception of temporal order in the millisecond time range. We observed better performance of forward WM tasks than backward ones, independently of the type of material used. Furthermore, the severity of auditory comprehension impairment correlated with the efficiency on both forward and backward VWM tasks and the backward SWM task. Further analysis revealed that TIP plays a crucial role only in the latter task. These results indicate the divergent pattern of interactions between WM and TIP depending on the type of WM tasks. Level of verbal competency appeared to play an important role in both VWM tasks, whereas TIP (which is associated with manipulation processes) appeared to be important for SWM, but only on the backward task.

Decision Making by People With Aphasia: A Comparison of Linguistic and Nonlinguistic Measures

Purpose Decision making involves multiple cognitive and linguistic processes. The extent to which these processes are involved depends, in part, on the conditions under which decision making is assessed. Because people with aphasia (PWA) have impaired language abilities and may also present with cognitive deficits, they may have difficulty during decision-making tasks. Yet little research exists on the decision-making abilities of PWA. Thus, the purposes of this study were to investigate the performance of PWA on linguistic and nonlinguistic decision-making measures and to explore the relationship between decision making and cognitive test performance. Method A quasi-experimental design was used to compare the performance of PWA (n = 16) and age- and education-matched control participants (n = 16) on three decision-making tasks: Making a Decision subtest from the Functional Assessment of Verbal Reasoning and Executive Strategies (linguistic decision-making task), Iowa Gambling Task (nonlinguistic decision-making task with ambiguity), and Game of Dice Task (nonlinguistic decision-making task without ambiguity). Participants also completed assessments of language, working memory, and executive functions. Scores on the three decision-making tasks were compared between groups, and cognitive influences on decision-making performance were examined using correlation analyses. Results PWA differed significantly from control participants on linguistic decision making, particularly when required to verbalize their rationale for making their decision. PWA and control participants did not differ significantly on measures of nonlinguistic decision making. Performance on multiple cognitive measures was correlated with performance on the linguistic reasoning task, as well as one of the nonlinguistic tasks (Game of Dice Task). Conclusions Decision-making tasks that are heavily dependent on language, such as those used in capacity assessments, may disadvantage PWA. Assessments of decision-making capacity should include communication supports for people with acquired communication disorders; further investigation in the areas of decision making and aphasia is needed.

Trajectories of memory, language, and visuoperceptual problems in people with stroke during the first year and controls in Colombia

AIM

Neuropsychological normative data for Latin America have been recently published, and for Colombia, in particular, but longitudinal neuropsychological outcomes after stroke have not yet been examined in this global region. The purpose of the current study was to compare functioning of individuals with stroke in Colombia, South America during the first year post-stroke to healthy controls across neuropsychological assessments of memory, language, and visuoperceptual impairments.

METHOD

A sample of 50 individuals with stroke (mean age = 51.58) and 50 matched healthy controls (mean age = 51.54) from Colombia were included in this study. Because of a lack of access to health services, individuals with stroke did not receive any inpatient or outpatient cognitive or behavioral rehabilitation. Participants were assessed on 10 visuoperceptual, language, and memory tasks at 3, 6, and 12   months.

RESULTS

Trajectories of neuropsychological performance were significantly worse among individuals with stroke than healthy controls across every index. Further, hierarchical linear models suggested that although both individuals with stroke and controls generally improved over time on these assessments, the improvements among individuals with stroke were often of no greater magnitude than the improvements seen in controls, suggesting extremely low levels of rehabilitation gains in Colombia. Only three of the 10 neuropsychological assessments did a significant time*group interaction occur, suggesting greater gains for the stroke group than controls.

CONCLUSION

These findings suggest profound disparities in post-stroke cognitive functioning in Colombia compared to other more developed global region and underscore the importance of comprehensive cognitive rehabilitation services for individuals with stroke in Colombia and other similar global regions. Implications for rehabilitation Because this study found only negligible cognitive improvements beyond practice effects over the first year after stroke in Colombia among individuals without access to acute rehabilitation, it is imperative that comprehensive cognitive rehabilitation services be implemented immediately during the acute rehabilitation period. Memory, language, and visuoperceptual training strategies can be implemented for people with stroke in underserved global regions as part of the standard of care for stroke rehabilitation. Cognitive rehabilitation strategies should be adapted into Spanish and pilot tested in Latin America to ensure cultural equivalence. Culturally competent cognitive rehabilitation strategies should be tailored based on varied educational and literacy levels.

Attention Deficits in Stroke Patients: The Role of Lesion Characteristics, Time from Stroke, and Concomitant Neuropsychological Deficits

Attention impairments are frequent in stroke patients with important consequences on the rehabilitation outcomes and quality of life. The aim of the study was to perform a comprehensive assessment of selective and intensive attention processes in a large population of brain-damaged patients, evaluating the influence of the side and site of the brain lesion, the time from stroke, and the concomitant presence of aphasia or neglect. We assessed 204 patients with a first unilateral brain lesion and 42 healthy individuals with three subtests of the Test of Attentional Performance (TAP): Alertness, Go-No Go, and Divided Attention. 44.4% of patients had an impairment in both intensive and selective aspects of attention, 5.6% had deficits only in the intensive component, and 31.8% had deficits only in selective tasks. More than 80% of the patients fell below the cut-off point on at least one task. Patients with a right hemispheric lesion (RHL) were more impaired than patients with a left hemispheric lesion (LHL) especially in tonic and phasic alertness. Patients with total anterior infarcts (TACI) presented the worst profile compared to other stroke subtypes, with a difference between total and lacunar subtypes in the Alertness test, independent of the presence of warning. Patients in the chronic phase had shorter RTs than acute patients only in the Alertness test. In patients with LHL, the presence of aphasia was associated with a greater deficit in selective attention. In patients with RHL, the presence of unilateral neglect was associated with impaired alertness and selective attention. Attention deficits are common after a unilateral first stroke. In keeping with the hierarchical organization of attention functions, results confirm the important role of the right hemisphere for the intensive components of attention, also highlighting the involvement of left hemisphere functioning for the selective aspects, possibly indicating a role of its linguistic functions.

Comprehension of Single Versus Combined Modality Information by People With Aphasia

Purpose Every adult with aphasia displays a unique constellation of language comprehension skills and varies in the benefit derived from different content presentation formats. For many, multiple modality presentation enhances comprehension. This study's purpose was to determine the comprehension benefits for people with mild, moderate, and severe aphasia when hearing, reading, or simultaneously hearing and reading single sentences. Method Twenty-seven adults with aphasia performed a repeated-measures experiment across 3 conditions. Participants read and/or listened to sentence stimuli and selected from 4 images the 1 matching the sentence. Participants also indicated condition preference. Results Participants demonstrated significantly greatest accuracy during simultaneous written and auditory stimulus presentation. Performance patterns varied within aphasia severity groups. Individuals with mild and moderate aphasia demonstrated minimal performance differences across conditions, and people with severe aphasia were significantly more accurate in the combined modality than the written-only modality. Overall, participants required the longest response time in the written-only condition; however, participants were most efficient with auditory content. Condition preferences did not always mirror accuracy; however, the majority reported a preference for combined content presentation. Conclusions Results suggest some people with aphasia may benefit from combined auditory and written modalities to enhance comprehension efforts.

Linked 4-Way Multimodal Brain Differences in Schizophrenia in a Large Chinese Han Population

Multimodal fusion has been regarded as a promising tool to discover covarying patterns of multiple imaging types impaired in brain diseases, such as schizophrenia (SZ). In this article, we aim to investigate the covarying abnormalities underlying SZ in a large Chinese Han population (307 SZs, 298 healthy controls [HCs]). Four types of magnetic resonance imaging (MRI) features, including regional homogeneity (ReHo) from resting-state functional MRI, gray matter volume (GM) from structural MRI, fractional anisotropy (FA) from diffusion MRI, and functional network connectivity (FNC) resulted from group independent component analysis, were jointly analyzed by a data-driven multivariate fusion method. Results suggest that a widely distributed network disruption appears in SZ patients, with synchronous changes in both functional and structural regions, especially the basal ganglia network, salience network (SAN), and the frontoparietal network. Such a multimodal coalteration was also replicated in another independent Chinese sample (40 SZs, 66 HCs). Our results on auditory verbal hallucination (AVH) also provide evidence for the hypothesis that prefrontal hypoactivation and temporal hyperactivation in SZ may lead to failure of executive control and inhibition, which is relevant to AVH. In addition, impaired working memory performance was found associated with GM reduction and FA decrease in SZ in prefrontal and superior temporal area, in both discovery and replication datasets. In summary, by leveraging multiple imaging and clinical information into one framework to observe brain in multiple views, we can integrate multiple inferences about SZ from large-scale population and offer unique perspectives regarding the missing links between the brain function and structure that may not be achieved by separate unimodal analyses.

Effects of a specially designed aerobic dance routine on mild cognitive impairment

Background

Mild cognitive impairment (MCI) is known as a transitional stage or phase between normal aging and dementia. In addition, it is associated with an increased risk of dementia. Research has shown that moderate-intensity exercise is associated with a decreased risk of cognitive impairment. Two recent studies demonstrated that dance interventions are associated with improved cognitive function in the elderly with MCI.

Purpose

We evaluated the effect of a moderate-intensity aerobic dance routine on the cognitive function in patients with MCI.

Patients and methods

This is a single-blind randomized controlled trial. Sixty MCI patients were randomized to receive either treatment (aerobic dance routine + usual care) or control (usual care only) for 3 months. All patients received usual care for an additional 3 months thereafter. The aerobic dance routine was a specially designed dance routine which involved cognitive effort for patients to memorize the complex movements. Wechsler memory scale-revised logical memory (WMS-R LM) and event-related evoked potentials (ERPs) P300 latency were used to assess patients’ cognitive function at baseline, 3 months, and 6 months.

Results

Twenty-nine patients received exercise therapy and 31 patients received usual care. Patients in the treatment group showed a greater improvement in memory (difference in WMS-R LM changes over 3 months 4.6; 95% CI 2.2, 7.0; p<0.001) and processing speed (difference in P300 latency changes over 6 months −20.0; 95% CI=−39.5, −0.4; p<0.05) compared to control.

Conclusion

This dance routine improves cognitive function, especially episodic memory and processing speed, in MCI patients and merits promotion in communities.

Links Between Short-Term Memory and Word Retrieval in Aphasia

PURPOSE

This study explored the relationship between anomia and verbal short-term memory (STM) in the context of an interactive activation language processing model.

METHOD

Twenty-four individuals with aphasia and reduced STM spans (i.e., impaired immediate serial recall of words) completed a picture-naming task and a word pair repetition task (a measure of verbal STM). Correlations between verbal STM and word retrieval errors made on the picture-naming task were examined.

RESULTS

A significant positive correlation between naming accuracy and verbal span length was found. More intricate verbal STM analyses examined the relationship between picture-naming error types (i.e., semantic vs. phonological) and 2 measures of verbal STM: (a) location of errors on the word pair repetition task and (b) imageability and frequency effects on the word pair repetition task. Results indicated that, as phonological word retrieval errors (relative to semantic) increase, bias toward correct repetition of high-imageability words increases.

CONCLUSIONS

Results suggest that word retrieval and verbal STM tasks likely rely on a partially shared temporary linguistic activation process.

Neuropsychological assessment of 86-year-old man with Broca's aphasia complaining of memory difficulties

We report the clinical assessment of J.P., an 86 year-old man with Broca's aphasia complaining of memory problems. Our aim was to objectively investigate his level of cognitive functioning using standardized neuropsychological tests in order to determine the nature of his memory impairment. J.P.'s medical history included left-middle cerebral artery (left-MCA) stroke, high frequency hearing loss, macular degeneration, and a recent hospitalization related to a fall. Results from his neuropsychological testing and from information gathered during the clinical interview with his wife suggested that a deficit in executive functioning might have been the source for some of his perceived memory problems. We were unable to detect any progressive cognitive decline that might have been suggestive of something more sinister. Despite his age J.P. was a fully functioning and highly contributing member of his society who was completing quite complex activities of daily living (ADLs). We provided J.P. with a compensatory set of strategies in order for him to circumvent his executive difficulties and impairment in expressive language. In the elderly population survivors of stroke are continuing to rise with improvements in drug treatment and primary care. This case study is important as it provides information on neuropsychological assessment in aphasia; and draws attention to valuable information in a client's clinical history that might help clarify the prognosis.

Short-Term Memory and Aphasia: From Theory to Treatment

This article reviews existing research on the interactions between verbal short-term memory and language processing impairments in aphasia. Theoretical models of short-term memory are reviewed, starting with a model assuming a separation between short-term memory and language, and progressing to models that view verbal short-term memory as a cognitive requirement of language processing. The review highlights a verbal short-term memory model derived from an interactive activation model of word retrieval. This model holds that verbal short-term memory encompasses the temporary activation of linguistic knowledge (e.g., semantic, lexical, and phonological features) during language production and comprehension tasks. Empirical evidence supporting this model, which views short-term memory in the context of the processes it subserves, is outlined. Studies that use a classic measure of verbal short-term memory (i.e., number of words/digits correctly recalled in immediate serial recall) as well as those that use more intricate measures (e.g., serial position effects in immediate serial recall) are discussed. Treatment research that uses verbal short-term memory tasks in an attempt to improve language processing is then summarized, with a particular focus on word retrieval. A discussion of the limitations of current research and possible future directions concludes the review.

Verbal and musical short-term memory: Variety of auditory disorders after stroke

Auditory cognitive deficits after stroke may concern language and/or music processing, resulting in aphasia and/or amusia. The aim of the present study was to assess the potential deficits of auditory short-term memory for verbal and musical material after stroke and their underlying cerebral correlates with a Voxel-based Lesion Symptom Mapping approach (VLSM). Patients with an ischemic stroke in the right (N=10) or left (N=10) middle cerebral artery territory and matched control participants (N=14) were tested with a detailed neuropsychological assessment including global cognitive functions, music perception and language tasks. All participants then performed verbal and musical auditory short-term memory (STM) tasks that were implemented in the same way for both materials. Participants had to indicate whether series of four words or four tones presented in pairs, were the same or different. To detect domain-general STM deficits, they also had to perform a visual STM task. Behavioral results showed that patients had lower performance for the STM tasks in comparison with control participants, regardless of the material (words, tones, visual) and the lesion side. The individual patient data showed a double dissociation between some patients exhibiting verbal deficits without musical deficits or the reverse. Exploratory VLSM analyses suggested that dorsal pathways are involved in verbal (phonetic), musical (melodic), and visual STM, while the ventral auditory pathway is involved in musical STM.

The role of the right hemisphere in semantic control: A case-series comparison of right and left hemisphere stroke

Semantic control processes guide conceptual retrieval so that we are able to focus on non-dominant associations and features when these are required for the task or context, yet the neural basis of semantic control is not fully understood. Neuroimaging studies have emphasised the role of left inferior frontal gyrus (IFG) in controlled retrieval, while neuropsychological investigations of semantic control deficits have almost exclusively focussed on patients with left-sided damage (e.g., patients with semantic aphasia, SA). Nevertheless, activation in fMRI during demanding semantic tasks typically extends to right IFG. To investigate the role of the right hemisphere (RH) in semantic control, we compared nine RH stroke patients with 21 left-hemisphere SA patients, 11 mild SA cases and 12 healthy, aged-matched controls on semantic and executive tasks, plus experimental tasks that manipulated semantic control in paradigms particularly sensitive to RH damage. RH patients had executive deficits to parallel SA patients but they performed well on standard semantic tests. Nevertheless, multimodal semantic control deficits were found in experimental tasks involving facial emotions and the 'summation' of meaning across multiple items. On these tasks, RH patients showed effects similar to those in SA cases - multimodal deficits that were sensitive to distractor strength and cues and miscues, plus increasingly poor performance in cyclical matching tasks which repeatedly probed the same set of concepts. Thus, despite striking differences in single-item comprehension, evidence presented here suggests semantic control is bilateral, and disruption of this component of semantic cognition can be seen following damage to either hemisphere.

Nonverbal Working Memory as a Predictor of Anomia Treatment Success

PURPOSE

The purpose of the study was to determine (a) reliability of the spatial span as a nonverbal working memory (WM) task in individuals with aphasia, (b) whether participation in anomia treatment changed spatial span scores, and (c) the degree to which visuospatial WM predicted response to anomia treatment.

METHOD

Eight individuals with chronic aphasia were repeatedly assessed on the forward and backward conditions of the spatial span over 4 weeks while undergoing treatment for anomia. Experiment 1 assessed reliability of the spatial span conditions and determined whether span scores changed after beginning anomia treatment. Experiment 2 investigated the spatial span as a predictor of anomia treatment success.

RESULTS

Results of Experiment 1 showed that 7 participants demonstrated stability of the forward condition of the spatial span, and 5 participants demonstrated stability of the backward condition across all sessions (p = .05). No participants showed an effect of aphasia treatment on span performance in either condition. Experiment 2 found that the backward span condition significantly predicted anomia treatment effect size, F(1, 6) = 15.202, p = .008.

CONCLUSIONS

Visuospatial WM abilities were highly predictive of response to anomia treatment, supporting an account of WM that includes a central processing mechanism.

Assessment and treatment of short-term and working memory impairments in stroke aphasia: a practical tutorial

BACKGROUND

Aphasia following stroke refers to impairments that affect the comprehension and expression of spoken and/or written language, and co-occurring cognitive deficits are common. In this paper we focus on short-term and working memory impairments that impact on the ability to retain and manipulate auditory-verbal information. Evidence from diverse paradigms (large group studies, case studies) report close links between short-term/working memory and language functioning in aphasia. This evidence leads to the hypothesis that treating such memory impairments would improve language functioning. This link has only recently been acknowledged in aphasia treatment but has not been embraced widely by clinicians.

AIMS

To examine the association between language, and short-term and working memory impairments in aphasia. To describe practical ways of assessing short-term and working memory functioning that could be used in clinical practice. To discuss and critically appraise treatments of short-term and working memory reported in the literature.

METHODS & PROCEDURES

Taking a translational research approach, this paper provides clinicians with current evidence from the literature and practical information on how to assess and treat short-term and working memory impairments in people with aphasia. Published treatments of short-term and/or working memory in post-stroke aphasia are discussed through a narrative review.

MAIN CONTRIBUTIONS

This paper provides the following. A theoretical rationale for adopting short-term and working memory treatments in aphasia. It highlights issues in differentially diagnosing between short-term, working memory disorders and other concomitant impairments, e.g. apraxia of speech. It describes short-term and working memory assessments with practical considerations for use with people with aphasia. It also offers a description of published treatments in terms of participants, treatments and outcomes. Finally, it critically appraises the current evidence base relating to the treatment of short-term and working memory treatments.

CONCLUSIONS

The links between short-term/working memory functioning and language in aphasia are generally acknowledged. These strongly indicate the need to incorporate assessment of short-term/working memory functioning for people with aphasia. While the supportive evidence for treatment is growing and appears to highlight the benefits of including short-term/working memory in aphasia treatment, the quality of the evidence in its current state is poor. However, because of the clinical needs of people with aphasia and the prevalence of short-term/working memory impairments, incorporating related treatments through practice-based evidence is advocated.

A new modified listening span task to enhance validity of working memory assessment for people with and without aphasia

Deficits in working memory (WM) are an important subset of cognitive processing deficits associated with aphasia. However, there are serious limitations to research on WM in aphasia largely due to the lack of an established valid measure of WM impairment for this population. The aim of the current study was to address shortcomings of previous measures by developing and empirically evaluating a novel WM task with a sentence-picture matching processing component designed to circumvent confounds inherent in existing measures of WM in aphasia. The novel WM task was presented to persons with (n=27) and without (n=33) aphasia. Results demonstrated high concurrent validity of a novel WM task. Individuals with aphasia performed significantly worse on all conditions of the WM task compared to individuals without aphasia. Different patterns of performance across conditions were observed for the two groups. Additionally, WM capacity was significantly related to auditory comprehension abilities in individuals with mild aphasia but not those with moderate aphasia. Strengths of the novel WM task are that it allows for differential control for length versus complexity of verbal stimuli and indexing of the relative influence of each, minimizes metalinguistic requirements, enables control for complexity of processing components, allows participants to respond with simple gestures or verbally, and eliminates reading requirements. Results support the feasibility and validity of using a novel task to assess WM in individuals with and without aphasia.

LEARNING OUTCOMES

Readers will be able to (1) discuss the limitations of current working memory measures for individuals with aphasia; (2) describe how task design features of a new working memory task for people with aphasia address shortcomings of existing measures; (3) summarize the evidence supporting the validity of the novel working memory task.

Do children with cerebral palsy benefit from computerized working memory training? Study protocol for a randomized controlled trial

Background

Cerebral palsy (CP) is the most common motor disability in childhood (2 to 3 per 1000 live births), and is frequently accompanied by cognitive impairments and behavioural problems. Children with CP are at increased risk of attention deficit disorder with or without hyperactivity (Attention Deficit Disorder (ADD)/Attention Deficit Hyperactivity Disorder (ADHD)) including working memory deficits. The primary aim of this study is to evaluate if cognitive training may improve working memory in children with CP.

Methods/Designs

The study is an investigator-blinded, randomized controlled trial with a stepped-wedge design that will include 115 schoolchildren with CP. Eligible for participation are children with CP, aged 7 to 15 years, who are able to follow instructions and handle a computer mouse. Exclusion criteria are the presence of photosensitive epilepsy, Gross Motor Function Classification System (GMFCS) level V (most severe CP) (Phys Ther 80: 974-985, 2000) and severe visual or hearing impairments. Following assessment of eligibility and baseline cognitive assessment the participants will be randomized to either cognitive working memory training or treatment-as-usual (‘control group’). The intervention is a computer-based working memory training program consisting of 25 daily sessions to be performed over a 5 to 6-week period at home. A neuropsychological assessment will be performed before and 4 to 6 weeks after completed training. When the latter assessment has been completed in the intervention group, the ‘control group’ will start on the same training program. Both groups will meet for a final neuropsychological assessment six months after completed training by an examiner unaware of group adherence.

Discussion

There is limited evidence for the effect of most interventions in children with CP, and evidence is completely lacking for interventions aiming to improve deficits in cognition, learning and behaviour. The proposed multicenter study, will bring forth comprehensive information about cognitive, neuropsychological, and daily-life functioning in children with CP aged between 7 and 15 years. In addition, the study will be the first to evaluate the effects of an intervention method to improve working memory in children with CP. If successful, computer-based working memory training may represent an efficient and cost-effective intervention for this group of children.

Trial registration

ClinicalTrials.gov Identifier: NCT02119364

Verbal and visuospatial span in logopenic progressive aphasia and Alzheimer's disease

Logopenic progressive aphasia (LPA) is a form of primary progressive aphasia (PPA) characterized by hesitant speech with marked impairment in naming and repetition. LPA is associated with brain atrophy in the left temporal and inferior parietal cortices and is predominantly associated with Alzheimer’s disease (AD) pathology. In contrast to LPA, ‘‘typical’’ AD is commonly associated with episodic memory disturbance and bilateral medial temporal lobe atrophy. Recent evidence suggests verbal short-term memory is more impaired than visuospatial short-term memory in LPA. This study investigated verbal and visuospatial short-term memory in 12 LPA and 12 AD patients matched for disease severity, and in 12 age- and education-matched healthy controls. Overall, both patient groups showed significantly reduced verbal and visuospatial spans compared with controls. In addition, LPA patients performed significantly worse than AD patients on both forward and backward conditions of the Digit Span task. In contrast, no difference was present between patient groups on either version of the Spatial Span task. Importantly, LPA patients showed better visuospatial than verbal span whereas AD patients and controls did not differ across modality. This study demonstrates the specificity of the short-term memory disturbance in LPA, which arises from a breakdown of the phonological system.

WAIS-IV Profiles in First-Ever Unilateral Ischemic Stroke Patients

This study aims to identify WAIS-IV profiles in unilateral ischemic stroke patients in rehabilitation (n = 107) compared to matched controls, to determine if patients demonstrate lateralized cognitive impairment, and to investigate whether aphasia has an additional effect on language and working memory subtests. Analyses revealed impairment in performance of stroke patients relative to controls, while effect of left-hemisphere stroke were large on subtests with language and processing speed demands, and of right-hemisphere stroke on subtests with visuo-spatial and processing speed demands. Aphasia had an additional effect on language, working memory and processing speed subtests. Findings confirm the pattern of cognitive deficits found with older versions of the WAIS and suggest that the WAIS-IV detects cognitive deficits in stroke patients.

Conceptualizing and Measuring Working Memory and its Relationship to Aphasia

BACKGROUND: General agreement exists in the literature that individuals with aphasia can exhibit a working memory deficit that contributes to their language processing impairments. Though conceptualized within different working memory frameworks, researchers have suggested that individuals with aphasia have limited working memory capacity, impaired attention-control processes as well as impaired inhibitory mechanisms. However, across studies investigating working memory ability in individuals with aphasia, different measures have been used to quantify their working memory ability and identify the relationship between working memory and language performance. AIMS: The primary objectives of this article are to (1) review current working memory theoretical frameworks, (2) review tasks used to measure working memory, and (3) discuss findings from studies that have investigated working memory as they relate to language processing in aphasia. MAIN CONTRIBUTION: Though findings have been consistent across studies investigating working memory ability in individuals with aphasia, discussion of how working memory is conceptualized and defined is often missing, as is discussion of results within a theoretical framework. This is critical, as working memory is conceptualized differently across the different theoretical frameworks. They differ in explaining what limits capacity and the source of individual differences as well as how information is encoded, maintained, and retrieved. When test methods are considered within a theoretical framework, specific hypotheses can be tested and stronger conclusions that are less susceptible to different interpretations can be made. CONCLUSIONS: Working memory ability has been investigated in numerous studies with individuals with aphasia. To better understand the underlying cognitive constructs that contribute to the language deficits exhibited by individuals with aphasia, future investigations should operationally define the cognitive constructs of interest and discuss findings within theoretical frameworks.

Aphasia severity and salivary cortisol over time

The current study explored the complicated interplay between aphasia and the stress biomarker, cortisol, in left-hemisphere (LH) and right-hemisphere (RH) stroke patients. Nineteen LH patients and 12 RH patients began the study between one to six months post stroke and were followed for three months. During this time, language skills were assessed monthly while afternoon salivary cortisol samples were collected biweekly. The LH and RH groups showed improvements in language test scores over the course of three months; however, only naming skills in the RH group appeared to be associated with afternoon salivary cortisol levels. Furthermore, contradicting previous reports regarding laterality and cortisol regulation in humans, the current study found that both LH patients and RH patients exhibited similar afternoon salivary cortisol levels across all time points.

Short-term and working memory impairments in aphasia

The aim of the present study is to investigate short-term memory and working memory deficits in aphasics in relation to the severity of their language impairment. Fifty-eight aphasic patients participated in this study. Based on language assessment, an aphasia score was calculated for each patient. Memory was assessed in two modalities, verbal and spatial. Mean scores for all memory tasks were lower than normal. Aphasia score was significantly correlated with performance on all memory tasks. Correlation coefficients for short-term memory and working memory were approximately of the same magnitude. According to our findings, severity of aphasia is related with both verbal and spatial memory deficits. Moreover, while aphasia score correlated with lower scores in both short-term memory and working memory tasks, the lack of substantial difference between corresponding correlation coefficients suggests a possible primary deficit in information retention rather than impairment in working memory.