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Roughly 30% of stroke survivors suffer from aphasia—a communication disorder that affects the ability to communicate effectively—but little is known about their healthcare expenditure or how it varies between aphasia subtypes. This study evaluates the relative differential in healthcare expenditure of anomic, Broca's, Wernicke's and Conduction aphasia and assesses expenditure between demographic cohorts Individual level data from the 2010 Moss Aphasia Psycholinguistic Project Database was matched with the 2010 Medical Expenditure Panel Survey using a propensity score algorithm based on functional, health, and demographic characteristics. Multilevel, generalized, nonlinear regression models were applied to the resulting data set to assess the correlation between annual healthcare expenditure, time post onset (tpo), sex, race, family size, marital status, income, education, aphasia type, and region of residence. Results were used to predict expenditure by aphasia subtype, race, and sex. Multiple distributional specifications tested the sensitivity and ensured the robustness of estimates. Regression results indicate that individuals with Broca's aphasia had statistically higher healthcare expenditures paying an average of $10,896.45 annually when compared to anomic ($7,927.60), Wernicke's ($7,096.22), and Conduction ($9,447.19) aphasias. Additionally, healthcare expenditure increased with each year of age (β=0.004, SE=0.005), but decreased with each year after stroke (β=-0.002, SE=0.001). Females (β=0.358, SE=0.131) and Blacks (β=0.103, SE=0.200) paid significantly more annually compared to males and Whites, respectively. Neither region of residence, income, nor level of education were significantly correlated with healthcare expenditure. This study showed that, while individuals with Broca's aphasia had higher average healthcare expenditure than other subtypes, the differential was not statistically significant. Sex and race cohorts did, however, show statistically significant differences in healthcare expenditures. While causality is outside the scope of this analysis, additional work is needed to determine the best strategy to mitigate these disparities. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Apraxia of speech (AOS) due to a postcentral infarction differs from conventional precentral AOS with respect to phonemic errors (phoneme substitution) which are more common than phonetic errors (phoneme distortion) and preserved accent and intonation. Clinical features of apraxia of speech caused by lesions in the postcentral gyrus have not yet been elucidated. Here, we report a patient with this lesion and show how postcentral apraxia of speech differs from the hitherto known precentral apraxia of speech. A 54‐year‐old man developed Broca's aphasia with apraxia of speech that resolved into pure apraxia of speech within 3 weeks following infarction of the postcentral gyrus. The diagnosis of apraxia of speech was based on the patient's effortful, slow speech and inconsistent phonetic distortions with phonemic paraphasia. The Western Aphasia Battery was used to examine the patient's speech samples. Speech was recorded using a digital voice recorder and transcribed into a narrow transcription of the International Phonetic Alphabet. The error types were categorized phonologically. The results revealed that (a) phonemic errors (vowel and consonant substitutions, also known as phonemic paraphasia) were more common than phonetic errors (vowel and consonant distortions). Similar to conduction aphasia, phonemic errors were more pronounced in confrontation naming than in repetition, accompanied by self‐correction, and (b) word accent and sentence intonation were preserved, although the speech was slow. These two features are characteristic of postcentral apraxia of speech, which can be differentiated from conventional precentral apraxia of speech. [ABSTRACT FROM AUTHOR]

Key Clinical Message Apraxia of speech (AOS) due to a postcentral infarction differs from conventional precentral AOS with respect to phonemic errors (phoneme substitution) which are more common than phonetic errors (phoneme distortion) and preserved accent and intonation. Abstract Clinical features of apraxia of speech caused by lesions in the postcentral gyrus have not yet been elucidated. Here, we report a patient with this lesion and show how postcentral apraxia of speech differs from the hitherto known precentral apraxia of speech. A 54‐year‐old man developed Broca's aphasia with apraxia of speech that resolved into pure apraxia of speech within 3 weeks following infarction of the postcentral gyrus. The diagnosis of apraxia of speech was based on the patient's effortful, slow speech and inconsistent phonetic distortions with phonemic paraphasia. The Western Aphasia Battery was used to examine the patient's speech samples. Speech was recorded using a digital voice recorder and transcribed into a narrow transcription of the International Phonetic Alphabet. The error types were categorized phonologically. The results revealed that (a) phonemic errors (vowel and consonant substitutions, also known as phonemic paraphasia) were more common than phonetic errors (vowel and consonant distortions). Similar to conduction aphasia, phonemic errors were more pronounced in confrontation naming than in repetition, accompanied by self‐correction, and (b) word accent and sentence intonation were preserved, although the speech was slow. These two features are characteristic of postcentral apraxia of speech, which can be differentiated from conventional precentral apraxia of speech.

Anomic aphasia is characterized by good comprehension and non-word repetition but poor naming. Two sub-types of deficits might be hypothesized: faulty access to preserved phonological representations or preserved access to impaired representations. Phonological errors may occur only when representations are impaired or in post-lexical deficits (conduction aphasia). We analysed the incidence of phonological naming errors of 30 individuals, 25 with anomic aphasia based on poor naming but good repetition and comprehension, and five with conduction aphasia based on poor naming and poor repetition. Individuals with anomic aphasia produced very few phonological errors compared to individuals with conduction aphasia (0–19.1% versus 42–66%). However, six individuals with anomia produced more than 11% phonological errors, suggesting two patterns of deficit: either impaired lexical representations or impaired access to them. The lack of phonological errors in most individuals with anomic aphasia suggests that access to the phonological output lexicon is semantically, not phonologically driven. [ABSTRACT FROM AUTHOR]

Stroke is a medical condition that affects the brain and represents a leading cause of death and disability. Associated with drug therapy, rehabilitative treatment is essential for promoting recovery. In the present work, we report an EEG-based study concerning a left ischemic stroke patient affected by conduction aphasia. Specifically, the objective is to compare the brain functional connectivity before and after an intensive rehabilitative treatment. The analysis was performed by means of local and global efficiency measures related to the execution of three tasks: naming, repetition and reading. As expected, the results showed that the treatment led to a balancing of the values of both parameters between the two hemispheres since the rehabilitation contributed to the creation of new neural patterns to compensate for the disrupted ones. Moreover, we observed that for both name and repetition tasks, shortly after the stroke, the global and local connectivity are lower in the affected lobe (left hemisphere) than in the unaffected one (right hemisphere). Conversely, for the reading task, global and local connectivity are higher in the impaired lobe. This apparently contrasting trend can be due to the effects of stroke, which affect not only the site of structural damage but also brain regions belonging to a functional network. Moreover, changes in network connectivity can be task-dependent. This work can be considered a first step for future EEG-based studies to establish the most suitable connectivity measures for supporting the treatment of stroke and monitoring the recovery process. [ABSTRACT FROM AUTHOR]

The application of ℓ1‐regularized machine learning models to high‐dimensional connectomes offers a promising methodology to assess clinical‐anatomical correlations in humans. Here, we integrate the connectome‐based lesion‐symptom mapping framework with sparse partial least squares regression (sPLS‐R) to isolate elements of the connectome associated with speech repetition deficits. By mapping over 2,500 connections of the structural connectome in a cohort of 71 stroke‐induced cases of aphasia presenting with varying left‐hemisphere lesions and repetition impairment, sPLS‐R was trained on 50 subjects to algorithmically identify connectomic features on the basis of their predictive value. The highest ranking features were subsequently used to generate a parsimonious predictive model for speech repetition whose predictions were evaluated on a held‐out set of 21 subjects. A set of 10 short‐ and long‐range parieto‐temporal connections were identified, collectively delineating the broader circuitry of the dorsal white matter network of the language system. The strongest contributing feature was a short‐range connection in the supramarginal gyrus, approximating the cortical localization of area Spt, with parallel long‐range pathways interconnecting posterior nodes in supramarginal and superior temporal cortex with anterior nodes in both ventral and—notably—in dorsal premotor cortex, respectively. The collective disruption of these pathways indexed repetition performance in the held‐out set of participants, suggesting that these impairments might be characterized as a parietotemporal disconnection syndrome impacting cortical area Spt and its associated white matter circuits of the frontal lobe as opposed to being purely a disconnection of the arcuate fasciculus. [ABSTRACT FROM AUTHOR]

Stroke is a medical condition that affects the brain and represents a leading cause of death and disability. Associated with drug therapy, rehabilitative treatment is essential for promoting recovery. In the present work, we report an EEG-based study concerning a left ischemic stroke patient affected by conduction aphasia. Specifically, the objective is to compare the brain functional connectivity before and after an intensive rehabilitative treatment. The analysis was performed by means of local and global efficiency measures related to the execution of three tasks: naming, repetition and reading. As expected, the results showed that the treatment led to a balancing of the values of both parameters between the two hemispheres since the rehabilitation contributed to the creation of new neural patterns to compensate for the disrupted ones. Moreover, we observed that for both name and repetition tasks, shortly after the stroke, the global and local connectivity are lower in the affected lobe (left hemisphere) than in the unaffected one (right hemisphere). Conversely, for the reading task, global and local connectivity are higher in the impaired lobe. This apparently contrasting trend can be due to the effects of stroke, which affect not only the site of structural damage but also brain regions belonging to a functional network. Moreover, changes in network connectivity can be task-dependent. This work can be considered a first step for future EEG-based studies to establish the most suitable connectivity measures for supporting the treatment of stroke and monitoring the recovery process.

COVID-19 following infection by SARS-CoV-2 can affect the brain causing confusion, depression, and dementia-like signs. Nonetheless, the presence of more specific neuropsychological signs because of COVID-19 remains unexplored. We report on LA, a patient who was affected by a left-hemisphere ischemic stroke, probably because of SARS-CoV-2. The patient showed a highly specific neuropsychological profile characterized by severe agraphia and some signs of conduction aphasia. All other cognitive and sensorimotor functions remained intact. We sustain that specific neuropsychological signs can be observed in patients with COVID-19. Therefore, in-depth and comprehensive neuropsychological assessment should be included to better explore and qualify the neuropsychological consequences of COVID-19. This is a new challenge for diagnosis and rehabilitation, with important consequences for the involved neuropsychological services. [ABSTRACT FROM AUTHOR]

Conduction aphasia is a language disorder occurred after a left-brain injury. It is characterized by fluent speech production, reading, writing and normal comprehension, while speech repetition is impaired. The aim of this study is to investigate the cortical responses, induced by language activities, in a sub-acute stroke patient affected by conduction aphasia before and after an intensive speech therapy training. The patient was examined by using High-Density Electroencephalogram (HD-EEG) examination, while was performing language tasks. the patient was evaluated at baseline and after two months after rehabilitative treatment. Our results showed that an intensive rehabilitative process, in sub-acute stroke, could be useful for a good outcome of language deficits. HD-EEG results showed that left parieto-temporol-frontal areas were more activated after 2 months of rehabilitation training compared with baseline. Our results provided evidence that an intensive rehabilitation process could contribute to an inter- and intra-hemispheric reorganization. [ABSTRACT FROM AUTHOR]

Conduction aphasia is a language disorder occurred after a left-brain injury. It is characterized by fluent speech production, reading, writing and normal comprehension, while speech repetition is impaired. The aim of this study is to investigate the cortical responses, induced by language activities, in a sub-acute stroke patient affected by conduction aphasia before and after an intensive speech therapy training. The patient was examined by using High-Density Electroencephalogram (HD-EEG) examination, while was performing language tasks. the patient was evaluated at baseline and after two months after rehabilitative treatment. Our results showed that an intensive rehabilitative process, in sub-acute stroke, could be useful for a good outcome of language deficits. HD-EEG results showed that left parieto-temporol-frontal areas were more activated after 2 months of rehabilitation training compared with baseline. Our results provided evidence that an intensive rehabilitation process could contribute to an inter- and intra-hemispheric reorganization.

Abstract: Objective: Studies using conventional full‐field visual evoked potentials (ffVEP) have reported subtle abnormalities in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). We hypothesize that these abnormalities can be detected in the majority of CIDP patients using enhanced methods. Methods: We performed a cross‐sectional noninterventional study comparing 18 CIDP patients and 18 matched healthy controls using multifocal VEP (mfVEP) as a technique with enhanced sensitivity to detect conduction abnormalities across the spectrum of optic nerve fibers. Patients with confounding diseases (ophthalmologic, diabetes mellitus) were excluded. Results: The mean amplitude and latency, as well as the low‐contrast visual acuity, did not differ between CIDP patients and controls. Subanalyses revealed latency differences concerning the superior sector of the visual field. Severity markers of CIDP (ODSS, motor nerve conduction velocity) were associated with mfVEP latency delay. Interpretation: We could not adduce evidence for clinically or diagnostically relevant visual pathway involvement in CIDP. The latency differences identified were very subtle and restricted to the superior visual field which cannot be readily explained biologically, anatomically, or pathologically. In summary, we conclude that our study revealed no relevant differences in mfVEP parameters between CIDP patients and controls. [ABSTRACT FROM AUTHOR]

Objective: Impairment of speech repetition following injury to the dorsal language stream is a feature of conduction aphasia, a well-described "disconnection syndrome" in adults. The impact of similar lesions sustained in infancy has not been established.Methods: We compared language outcomes in term-born individuals with confirmed neonatal stroke (n = 30, age = 7-18 years, left-sided lesions in 21 cases) to matched controls (n = 40). Injury to the dorsal and/or ventral language streams was assessed using T1 - and T2 -weighted magnetic resonance imaging (MRI) and diffusion tractography. Language lateralization was determined using functional MRI.Results: At the group level, left dorsal language stream injury was associated with selective speech repetition impairment for nonwords (p = 0.021) and sentences (p < 0.0001). The majority of children with significant repetition impairment had retained left hemisphere language representation, but right hemisphere dominance was correlated with minimal or absent repetition deficits. Post hoc analysis of the repetition-impaired group revealed additional language-associated deficits, but these were more subtle and variable.Interpretation: We conclude that (1) despite the considerable plasticity of the infant brain, early dorsal language stream injury can result in specific and long-lasting problems with speech repetition that are similar to the syndrome of conduction aphasia seen in adults; and (2) language reorganization to the contralateral hemisphere has a protective effect. Ann Neurol 2018;83:664-675 Ann Neurol 2018;83:664-675. [ABSTRACT FROM AUTHOR]

This study sought to investigate stress production in Spanish by patients with Broca's (BA) and conduction aphasia (CA) as compared to controls. Our objectives were to assess whether: a) there were many abnormal acoustic correlates of stress as produced by patients, b) these abnormalities had a phonetic component and c) ability for articulatory compensation for stress marking was preserved. The results showed abnormal acoustic values in both BA and CA's productions, affecting not only duration but also F0 and intensity cues, and an interaction effect of stress pattern and duration on intensity cubes in BA, but not in CA or controls. The results are interpreted as deriving from two different underlying phenomena: in BA, a compensatory use of intensity as a stress cue in order to avoid 'equal stress'; in CA, related to either a 'subtle phonetic deficit' involving abnormal stress acoustic cue-processing or to 'clear-speech' effects. [ABSTRACT FROM AUTHOR]

Concerns over sustainability in the built environment have resulted in continuous efforts to improve the performance of glazed façade systems and hence indoor comfort and building energy conservation. An innovative façade system where parallel transparent plastic slats are sandwiched between glass panes to form a Parallel Slat Transparent Insulation Material (PS-TIM) is proposed as a strategy to effectively reduce coupled convective and radiative heat transfer between the panes of a double glazed window. This strategy increases the thermal resistance of the façade, while maintaining access to daylight. A numerical investigation of the thermal and optical performance of this façade system is presented. Detailed modelling of the thermal characteristics of a double glazed window containing PS-TIM systems was carried out for different cell aspect ratios (defined by the thickness of window air cavity and slat interval distance), slat thickness and slat properties (conductivities and emissivities) using a validated Computational Fluid Dynamic (CFD) model. The CFD predictions show that: 1) an aspect ratio of 0.35 can provide full suppression of convection; 2) the PS-TIM structure can achieve a 35–46% reduction in thermal conductance compared with the same double glazing in the absence of PS-TIM; 3) material conductivity, thickness and emissivity have a more apparent influence on small cell structures than large cell structures. In addition, a simple analysis of U-value and light transmittance at various solar incidence angles was undertaken. The results provide a better understanding of the benefits of PS-TIM in terms of energy saving and offer suggestions for the improved design of glazing façade systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: Despite the potential behavioral and neurological benefits of Mindfulness Meditation (MM), its use in treating stroke related communication disabilities appears to be underexplored. Specifically, aphasia, a language disorder resulting from stroke, may be amenable to the benefits of MM because of the observed attention problems often underlying the language symptoms. OBJECTIVE: The current paper presents a case report of an adult with aphasia who was trained in MM. METHOD: An adult with aphasia completed a five-day mindfulness training, and was assessed on measures of language, attention, and physiological measures of cortisol and heart rate variability. She completed four assessments: two baseline measures, immediately post training, and one week post training (maintenance). RESULTS: Overall, changes were observed in both psychophysiological measures (heart rate and heart rate variability) and behavioral measures (word productivity, phrase length, word generation, decreased impulsivity, and increased attention). CONCLUSION: Given the psychophysiological and behavioral changes observed in this individual, further exploration of the influence of MM in the treatment of post-stroke aphasia is warranted. [ABSTRACT FROM AUTHOR]

Phonological errors seldom affect number words (Bencini et al., 2011). Current views suggest that this effect arises at the post-lexical (buffer) level: the basic phonological building blocks of ordinary words are phonemes, but the building blocks of number words are whole words. Dotan and Friedman (2010) suggested that the same effect holds for function words and morphological affixes. Case report. P.M. is a 77-year-old, Italian speaking, right-handed man, with 13 years of education. He had a left hemisphere stroke which resulted in conduction aphasia. Speech production was well articulated but affected by severe phonological disorders. An MRI showed a lesion in the left temporo-parietal areas. Methods. PM was administered: Repetition and Reading aloud of function word categories, cardinal and ordinal numbers in word lists and in sentences. Function words included the most frequent and shortest words in the Italian lexicon. Reading and repetition of number words within culturally transmitted expressions (e.g., “Four wheel drive”). Number words production in response to simple arithmetical operations. Questions requiring a numerical response (e.g., “days in a year?”) Inflected verbs. Reading and repetition of words with an embedded number word. Results. Results for reading aloud and repetition of word categories are shown in Table 1. Cardinal numbers elicited about one fifth of all phonological errors made on function word categories, even short and extremely frequent ones. No phonological errors were detected when PM had to produce the result of arithmetical operations. Cardinal numbers were frequently substituted by other cardinal numbers. Number words in transmitted expressions contained phonological errors in both reading aloud tasks although less than in the other word categories. Phonological errors were counted separately for the root and the bound morpheme on inflected verbs: there was no difference. Words with an embedded number word elicited an equal proportion of phonological errors in the number portion and in the non-number portion. In sentences only number words were spared; free standing function words and bound morphemes were as affected as other word categories. Discussion. These findings seem to set cardinal number words apart in the phonological output buffer from other possible building blocks of preassembled phonological units (like function words and bound morphemes). Building blocks constituted by numbers are more cohesive than the blocks constituted by function words and bound morphemes. Bencini et al. (2011) argued that numbers are recursive and consist of basic lexical units which are then combined following syntactic rules. This property would make number words resistant to damage in the phonological buffer.

Assessment of brain-damaged subjects presenting with dissociated repetition deficits after selective injury to either the left dorsal or ventral auditory pathways can provide further insight on their respective roles in verbal repetition. We evaluated repetition performance and its neural correlates using multimodal imaging (anatomical MRI, DTI, fMRI and 18FDG-PET) in a female patient with transcortical motor aphasia (TCMA) and in a male patient with conduction aphasia (CA) who had small contiguous but non-overlapping left perisylvian infarctions. Repetition in the TCMA patient was fully preserved except for a mild impairment in nonwords and digits, whereas the CA patient had impaired repetition of nonwords, digits and word triplet lists. Sentence repetition was impaired, but he repeated novel sentences significantly better than clichés. The TCMA patient had tissue damage and reduced metabolism in the left sensorimotor cortex and insula. DTI showed damage to the left temporo-frontal and parieto-frontal segments of the arcuate fasciculus (AF) and part of the left ventral stream together with well-developed right dorsal and ventral streams, as has been reported in more than one-third of females. The CA patient had tissue damage and reduced metabolic activity in the left temporoparietal cortex with additional metabolic decrements in the left frontal lobe. DTI showed damage to the left temporo-parietal and temporo-frontal segments of the AF, but the ventral stream was spared. The direct segment of the AF in the right hemisphere was also absent with only vestigial remains of the other dorsal subcomponents present, as is often found in males. fMRI during word and nonword repetition revealed bilateral perisylvian activation in the TCMA patient suggesting recruitment of spared segments of the left dorsal stream and right dorsal stream with propagation of signals to temporal lobe structures suggesting a compensatory reallocation of resources via the ventral streams. The CA p

We present a single case of a right-handed female patient, RH, who was categorized as suffering from conduction aphasia. She presented no articulatory problems during spontaneous speech but made a significant number of phonological paraphasias in naming and repetition tasks. The number of errors increased for long words and pseudowords. This pattern of results points to damage in the “Phonological Output Buffer” (POB) as the basis of this disorder. However, this patient did not make mistakes when reading words and pseudowords aloud, even when we introduced a delay between the presentation of the word and its production to test the working memory resources of the phonological buffer. Furthermore, the patient’s ability to name objects, repeat words, and write to dictation improved with her degree of familiarity with the items. The damage could be situated at the point where phonemes are selected and ordered to produce words. We posit that the deficits observed in this patient, and the differences encountered between her performance and that of others described in the literature, in particular in reading tasks, can be explained by considering POB damage to be gradual in nature. According to this explanation, the performance of patients with damage to the POB will depend on the amount of information provided by the stimulus (word/nonword), the language particularities (regular/irregular), and the nature of the task demands (repetition, writing, naming, or reading). [ABSTRACT FROM AUTHOR]

The processing of nonverbal auditory stimuli has not yet been sufficiently investigated in patients with aphasia. On the basis of a duration discrimination task, we examined whether patients with left-sided cerebrovascular lesions were able to perceive time differences in the scale of approximately 150 ms. Further linguistic and memory-related tasks were used to characterize more exactly the relationships in the performances between auditory nonverbal task and selective linguistic or mnemonic disturbances. All examined conduction aphasics showed increased thresholds in the duration discrimination task. The low thresholds on this task were in a strong correlative relation to the reduced performances in repetition and working memory task. This was interpreted as an indication of a pronounced disturbance in integrating auditory verbal information into a long-term window (sampling disturbance) resulting in an additional load of working memory. In order to determine the lesion topography of patients with sampling disturbances, the anatomical and psychophysical data were correlated on the basis of a voxelwise statistical approach. It was found that tissue damage extending through the insula, the posterior superior temporal gyrus, and the supramarginal gyrus causes impairments in sequencing of time-sensitive information. [ABSTRACT FROM AUTHOR]

Research on aphasia has struggled to identify apraxia of speech (AoS) as an independent deficit affecting a processing level separate from phonological assembly and motor implementation. This is because AoS is characterized by both phonological and phonetic errors and, therefore, can be interpreted as a combination of deficits at the phonological and the motoric level rather than as an independent impairment. We apply novel psycholinguistic analyses to the perceptually phonological errors made by 24 Italian aphasic patients. We show that only patients with relative high rate (>10%) of phonetic errors make sound errors which simplify the phonology of the target. Moreover, simplifications are strongly associated with other variables indicative of articulatory difficulties – such as a predominance of errors on consonants rather than vowels – but not with other measures – such as rate of words reproduced correctly or rates of lexical errors. These results indicate that sound errors cannot arise at a single phonological level because they are different in different patients. Instead, different patterns: (1) provide evidence for separate impairments and the existence of a level of articulatory planning/programming intermediate between phonological selection and motor implementation; (2) validate AoS as an independent impairment at this level, characterized by phonetic errors and phonological simplifications; (3) support the claim that linguistic principles of complexity have an articulatory basis since they only apply in patients with associated articulatory difficulties. [ABSTRACT FROM AUTHOR]

The present study explores the functional neuroanatomy of the phonological production system in an Italian aphasic patient (SP) who developed conduction aphasia of the reproduction type following brain surgery. SP presented with two peculiar features: (1) his lesion was localized in the superior temporal gyrus, just posterior to the primary auditory cortex and anterior/inferior to and neighboring the Sylvian parietal temporal (Spt) area, and (2) he presented with severely impaired repetition and spelling from dictation of words and pseudowords but spared reading-aloud of words and pseudowords. Structural, functional, fiber tracking and intraoperative findings were combined to analyze SP's pattern of performance within a widely used sensorimotor control scheme of speech production. We found a dissociation between an interrupted sector of the arcuate fasciculus terminating in STG, known to be involved in phonological processing, and a part of the arcuate fasciculus terminating in MTG, which is held to be involved in lexical-semantic processing. We argue that this phonological deficit should be interpreted as a disorder of the feedback system, in particular of the auditory and somatosensory target maps, which are assumed to be located along the Spt area. In patient SP, the spared part of the left arcuate fasciculus originating in MTG may support an unimpaired reading performance, while the damaged part of the left arcuate fasciculus originating in STG may be responsible for his impaired repetition and spelling from dictation. [ABSTRACT FROM AUTHOR]

The usual approach to language disorders relies on standardised evaluations in which pattern-tests characterise the subject's status according to the classical aphasiological typology. Those data are then analysed to support a traditional prevalent criterion for the distinction between "normal" and "pathological" linguistic performance, which is strictly focused on a quantitative approach. In the present study a method for evaluation and treatment of aphasia is proposed in which socio-cultural conditions are emphasised, in order to expand this conventional criterion as to encompass a qualitative (individualised) one. Although the methodology draws the attention, the results here obtained also point to the importance of re-evaluating what is presently considered as the most appropriate criterion for "normal" cognitive processes, particularly those related to language.Na literatura relativa à neuropsicologia da linguagem prevalece como modelo de investigação a adoção de testes destinados à avaliação normatizada de indivíduos afásicos, o que permite uma análise padronizada e subsequentemente a classificação do sujeito de acordo com as tipologias afasiológicas clássicas. Neste contexto, tais dados estão sendo considerados à luz do critério atualmente vigente, que propõe uma distinção estritamente quantitativa entre o desempenho linguístico "normal" e o "patológico". Neste estudo desenvolvemos abordagem metodológica para avaliação e tratamento de sujeitos afásicos com o intuito de priorizar suas condições sócio-culturais, incorporando assim ao critério convencional um aspecto eminentemente qualitativo. Ainda que o objeto do estudo seja a metodologia apresentada, os resultados obtidos indicam a importância de debate em tomo de reavaliação do que se considera presentemente como critério de "normalidade" para análise dos processos cognitivos, e em particular da linguagem.

Knowledge on the patterns of repetition amongst individuals who develop language deficits in association with right hemisphere lesions (crossed aphasia) is very limited. Available data indicate that repetition in some crossed aphasics experiencing phonological processing deficits is not heavily influenced by lexical-semantic variables (lexicality, imageability, and frequency) as is regularly reported in phonologically-impaired cases with left hemisphere damage. Moreover, in view of the fact that crossed aphasia is rare, information on the role of right cortical areas and white matter tracts underpinning language repetition deficits is scarce. In this study, repetition performance was assessed in two patients with crossed conduction aphasia and striatal/capsular vascular lesions encompassing the right arcuate fasciculus (AF) and inferior frontal-occipital fasciculus (IFOF), the temporal stem and the white matter underneath the supramarginal gyrus. Both patients showed lexicality effects repeating better words than nonwords, but manipulation of other lexical-semantic variables exerted less influence on repetition performance. Imageability and frequency effects, production of meaning-based paraphrases during sentence repetition, or better performance on repeating novel sentences than overlearned clichés were hardly ever observed in these two patients. In one patient, diffusion tensor imaging disclosed damage to the right long direct segment of the AF and IFOF with relative sparing of the anterior indirect and posterior segments of the AF, together with fully developed left perisylvian white matter pathways. These findings suggest that striatal/capsular lesions extending into the right AF and IFOF in some individuals with right hemisphere language dominance are associated with atypical repetition patterns which might reflect reduced interactions between phonological and lexical-semantic processes.

Ever since the 19th century, the standard model for spoken language processing has assumed two pathways for repetition - a phonological pathway and a semantic pathway - and this idea has gained further support in the last decade. First, recent in vivo tractography studies have demonstrated both the ‘dorsal’ (via arcuate fasciculus) and ‘ventral’ (via extreme capsule and uncinate fasciculus) pathways connecting from the primary auditory area to the speech-motor area, the latter of which passes through a brain area associated with semantic processing (anterior temporal lobe). Secondly, neuropsychological evidence for the role of semantics in repetition is conduite d’approche, a successive phonological improvement (sometimes non-improvement) in aphasic patients’ response by repeating several times in succession. Crucially, conduite d’approche is observed in patients with neurological damage in/around the arcuate fasciculus. Successful conduite d’approche is especially clear for semantically-intact patients and it occurs for real words rather than for nonwords. These features have led researchers to hypothesize that the patients’ disrupted phonological output is ‘cleaned-up’ by intact lexical-semantic information before the next repetition. We tested this hypothesis using the neuroanatomically-constrained dual dorsal-ventral pathway computational model. The results showed that (a) damage to the dorsal pathway impaired repetition; (b) in the context of recovery, the model learned to compute a correct repetition response following the model’s own noisy speech output (i.e., successful conduite d’approche); (c) this behavior was more evident for real words than nonwords; and (d) activation from the ventral pathway contributed to the increased rate of successful conduite d’approche for real words. These results suggest that lexical-semantic ‘clean-up’ is key to this self-correcting mechanism, supporting the classic proposal of two pathways for repetition.

Background: The syndrome of conduction aphasia is an umbrella term to label clinically heterogeneous language disorders that all include a deficit of repetition due to impaired immediate memory or, in some patients, impaired speech production. The present article reviews the currently available literature on conduction aphasia. It covers aspects of the history of conduction aphasia as a fascicular disconnection syndrome and the objections to this view and discusses the proposed subtypes of this syndrome and the underlying cortical and white matter lesions. Aims: The primary objectives of this article are to critically review the influence of historical concepts on recent approaches to optimise existing theoretical synergies. In addition, the article seeks to advance our understanding of the first steps of verbal auditory processing in individuals with normal and impaired language skills. Main Contribution: We present first indications for an involvement of the left hemisphere in both short- and long-term integration of auditory information derived by examining patients with (conduction) aphasia. Conclusions: Conduction aphasia may result from left hemisphere cortical lesions or from a disconnection of critical bundles of axons (fibre tract). The exact course of the fibre tract connections and the cortical regions involved in conduction aphasia remains controversial. [ABSTRACT FROM AUTHOR]

Introduction: No data about the specific outcome of aphasia after thrombolysis are available. Our aim was to describe the severity and type of aphasia after stroke thrombolysis. Methods: This retrospective cohort study included consecutive aphasic patients hospitalized in the Stroke Unit of Dijon (University Hospital, France) between 2004 and 2009 for a first-ever ischemic stroke of the left middle cerebral artery. Aphasic syndromes and their severity (French version of the Boston Diagnostic Aphasia Examination) were evaluated during the first week and 3 months after stroke. Results: In multivariate analyses, the severity of aphasia in the 37 thrombolysed patients was milder than in the 38 nonthrombolysed patients during the first week (adjusted OR = 10.13, 95% CI: 2.43-42.28, p = 0.002) and at 3 months (adjusted OR = 8.44, 95% CI: 2.76-25.80, p = 0.001). The frequency of mild aphasia (conduction or atypical) was not significantly higher in thrombolysed patients during the first week after stroke (adjusted OR = 5.80, 95% CI: 0.82-41.16, p = 0.079). Conclusion: The severity of aphasia during the first week and 3 months after stroke is milder in thrombolysed than in nonthrombolysed patients, perhaps because of a greater frequency of conduction and mild atypical aphasia. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Highlights: [•] We present three experiments examining paired associate learning (PAL) deficits in children with dyslexia. [•] Children with dyslexia showed impairments only in PAL tasks requiring verbal output. [•] We found no evidence for crossmodal associative learning deficits in dyslexia. [•] PAL deficits stem from the phonological form learning component of the task. [Copyright &y& Elsevier]