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Background Persons with aphasia (PWAs) manifest multifaceted deficits like auditory comprehension, spoken language, reading, and writing to varying degrees. Of these, the most debilitating signs are reading and writing impairment. Of late, PWAs express greater interest to improve their reading and writing skills. The deficits in these skills along with deficits in spoken language limit their participation in the community. Reading and writing may be altered contrarily in various stroke conditions across the left and right hemisphere lesions, just like how linguistic impairments are mutually exclusive. Thus, it must be rational to reconcile the possible role of the right hemisphere to process reading and writing inversely alike spoken abilities. Additionally, investigations on reading and writing deficits in left cerebrovascular atrophy (CVA) aphasics and right CVA aphasics (crossed aphasia) are seldom reported in the literature with relevance to Indian population focusing Indian languages. The study aims to compare reading and writing abilities across PWAs with left CVA and right CVA (crossed aphasia). Methodology The study recruited four native Kannada speaking PWAs (6 months poststroke) aged between 40 and 70 years with impaired linguistic abilities secondary to stroke through convenient sampling. Western Aphasia Battery-Kannada was administered to identify aphasic component, specifically to evaluate the language, reading, and writing aspects in detail and the scores were analyzed based on the scoring. Results Descriptive statistics revealed both left and crossed PWAs performed equipotent on linguistics tasks. However, reading abilities were better in left CVA individuals and writing was better in crossed PWAs on comparing the mean scores. Correlation analysis revealed positive correlation between language and reading-writing abilities of left CVA PWAs. Negative correlation was evinced in crossed PWAs. Hence, reading and writing difficulties in crossed aphasia can be mostly ascribed to impairment in peripheral mechanisms involved in visual and/or kinesthetic information processing as the right hemisphere is most viable to these processes. Conclusion The study highlights the unique pattern of reading and writing abilities in crossed aphasia condition. However, careful examination of dissociations in acquired spoken language and written language abilities across differential neuronal networks through larger samples in the future research is warranted. [ABSTRACT FROM AUTHOR]

Background: Aphasia is a common neurocognitive disorder caused by impaired speech and language, with stroke being the most frequent cause. The neuroanatomical mechanism underlying this condition is not yet fully understood. Case description: This case describes a 74-year-old Caucasian woman admitted with a clinical picture of right total anterior circulation infarct (TACI) and aphasia, scoring 17 on the National Institutes of Health Stroke Scale. Neuroimaging showed a large cortico-subcortical frontotemporoparietal and insular infarct involving the basal ganglia of the right hemisphere and bilateral focal atherosclerotic stenosis on the M1 segment of the middle cerebral artery. There was no left hemispheric lesion or abnormal electric activity on the electroencephalogram. A formal evaluation was compatible with transcortical motor aphasia. The aetiological study revealed atrial fibrillation, and the case was admitted as an ischaemic stroke of undetermined aetiology with two possible causes – intracranial atherosclerotic stenosis or atrial fibrillation. Conclusion: Our patient fulfilled all the formal criteria for crossed aphasia in dextral (CAD): aphasia, a lesion in the right hemisphere coupled with the structural integrity of the left hemisphere, an established preference for right-hand use without a familial history of left-handedness individuals, and an absence of brain damage in childhood. Our patient’s case adds to the evidence that deep structures – alone or in combination with cortical structures – are primarily affected in CAD.

Progressive supranuclear palsy (PSP) with predominant frontal presentation (PSP‐F) is a clinical phenotype of PSP that is characterized by frontal cognitive impairment and behavioral changes. Here, we report on a patient with pathologically diagnosed PSP‐F in whom we were able to observe temporal changes of the clinical manifestations. A 77‐year‐old right‐handed man developed progressive nonfluent aphasia (PNFA) at the age of 69 years, festinating gait, and clumsiness of his left arm at age 75, disinhibition at age 76, and unprovoked falls at age 77. Neurological examination at age 77 revealed limb‐kinetic apraxia of the left upper and lower limbs, rigidity, cortical sensory loss, and vertical supranuclear gaze palsy. According to the Movement Disorder Society clinical diagnostic criteria for PSP, his clinical manifestations shifted from suggestive PSP with predominant speech/language disorder to probable PSP‐F over nine years. Cerebral atrophy on brain magnetic resonance imaging and decreased accumulation of 99mTc‐ECD on cerebral blood flow single‐photon emission computed tomography were noted with right side predominance. Pathologically, 4‐repeat tau‐immunoreactive globose‐type neurofibrillary tangles, coiled bodies, tufted astrocytes, and neuropil threads were observed predominantly in the frontal cortex. Tau pathology of the substantia nigra, locus coeruleus and subthalamic nucleus was mild. These findings suggested that localized tau pathology involving the pars opercularis extended to the precentral gyrus, prefrontal cortex, and brainstem. This case report demonstrates that PSP‐F can present as a PNFA due to crossed aphasia. [ABSTRACT FROM AUTHOR]

It is not conclusively explored what kind of reorganisation processes are set off after a stroke with resulting aphasia. Since the development of functional Magnetic Resonance Imaging (fMRI), linguistic processes and their neural representation have been researched, especially in aphasic patients after left hemispheric insult. The situation differs in aphasic patients with crossed aphasia or aphasia after a right hemispheric lesion, for which only few studies have been carried out. In order to close this gap, the present study deals with the localisation of language functions in the brain of patients with crossed aphasia and right hemispheric language dominance. The objective of the current study was to provide insights into the neural correlates of continuous aphasic language production of patients with right hemispheric language dominance. Based on the current state of research, a mirror image representation was expected. Two patients with fluent aphasia due to right hemisphere lesions, one presenting with crossed aphasia, described complex pictures. The continuous language output was transcribed and categorised into events. Lexical search (i.e. the difference between unimpaired speaking and word-finding difficulties) was analysed using fMRI. The neural activation clusters were compared with the corresponding areas of a control group consisting of 12 patients with left hemispheric aphasia. The analysis of the behavioural data revealed word-finding difficulties as one of the most limiting factors in the spontaneous language output of the patients. The neural correlates of lexical search (unimpaired minus impaired) were observed in four activation clusters both patients had in common. Each cluster was predominantly localised in the contra-lesional hemisphere. Compared to the corresponding areas of the control group, in general, a mirrored image representation could be confirmed. The combination of detailed linguistic analysis and fMRI confirmed the assumption of mirrored language organisation for anomia in continuous language production. Moreover, the study might add to a more general understanding of the contribution of the contra-lesional hemisphere to language recovery in aphasia after left or right hemisphere damage. [ABSTRACT FROM AUTHOR]

Crossed aphasia has been reported mainly as post-stroke aphasia resulting from brain damage ipsilateral to the dominant right hand. Here, we described a case of a crossed nonfluent/agrammatic primary progressive aphasia (nfvPPA), who developed a corticobasal syndrome (CBS). We collected clinical, cognitive, and neuroimaging data for four consecutive years from a 55-year-old right-handed lady (JV) presenting with speech disturbances. 18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) and DaT-scan with (123)I-Ioflupane were obtained. Functional MRI (fMRI) during a verb naming task was acquired to characterize patterns of language lateralization. Diffusion tensor MRI was used to evaluate white matter damage within the language network. At onset, JV presented with prominent speech output impairment and right frontal atrophy. After 3 years, language deficits worsened, with the occurrence of a mild agrammatism. The patient also developed a left-sided mild extrapyramidal bradykinetic-rigid syndrome. The clinical picture was suggestive of nfvPPA with mild left-sided extrapyramidal syndrome. At this time, voxel-wise SPM analyses of (18)F-FDG PET and structural MRI showed right greater than left frontal hypometabolism and damage, which included the Broca's area. DaT-scan showed a reduced uptake in the right striatum. FMRI during naming task demonstrated bilateral language activations, and tractography showed right superior longitudinal fasciculus (SLF) involvement. Over the following year, JV became mute and developed frank left-sided motor signs and symptoms, evolving into a CBS clinical picture. Brain atrophy worsened in frontal areas bilaterally, and extended to temporo-parietal regions, still with a right-sided asymmetry. Tractography showed an extension of damage to the left SLF and right inferior longitudinal fasciculus. We report a case of crossed nfvPPA followed longitudinally and studied with advanced neuroimaging techniques. The results highlight a complex interaction between individual premorbid developmental differences and the clinical phenotype.

交叉性失语是一组由于右利手者右侧大脑半球损伤引起的获得性语言障碍综合征，在卒 中患者中的发病率为0.38%～4.6%，包括镜像失语与非典型失语，口语表达障碍多数为非流利性失语。 交叉性失语的发病机制目前仍存在争议，越早进行康复训练，预后越好。本文从交叉性失语的发病 机制、临床特点、影像学检查及康复训练的研究进展进行综述，以提高临床医师的重视，从而为交 叉性失语的诊治提供理论依据。 Abstract: Crossed aphasia (CA) refers to aphasia occurring after right cerebral hemisphere injure in right-handed individuals. The incidence of CA in stroke patients is 0.38%-4.6%. CA includes mirror image crossed aphasia and anomalous crossed aphasia, and impaired oral expression mainly presented with non-fluent aphasia. The mechanism of CA remains unclear. Previous studies have showed that the earlier the rehabilitation, the better the prognosis. This paper reviewed the pathogenesis, clinical features, imaging characteristics and rehabilitation of CA, to provide a reference for diagnosis and treatment of CA.

Background: Aphasia is a common neurocognitive disorder caused by impaired speech and language, with stroke being the most frequent cause. The neuroanatomical mechanism underlying this condition is not yet fully understood., Case Description: This case describes a 74-year-old Caucasian woman admitted with a clinical picture of right total anterior circulation infarct (TACI) and aphasia, scoring 17 on the National Institutes of Health Stroke Scale. Neuroimaging showed a large cortico-subcortical frontotemporoparietal and insular infarct involving the basal ganglia of the right hemisphere and bilateral focal atherosclerotic stenosis on the M1 segment of the middle cerebral artery. There was no left hemispheric lesion or abnormal electric activity on the electroencephalogram. A formal evaluation was compatible with transcortical motor aphasia. The aetiological study revealed atrial fibrillation, and the case was admitted as an ischaemic stroke of undetermined aetiology with two possible causes - intracranial atherosclerotic stenosis or atrial fibrillation., Conclusion: Our patient fulfilled all the formal criteria for crossed aphasia in dextral (CAD): aphasia, a lesion in the right hemisphere coupled with the structural integrity of the left hemisphere, an established preference for right-hand use without a familial history of left-handedness individuals, and an absence of brain damage in childhood. Our patient's case adds to the evidence that deep structures - alone or in combination with cortical structures - are primarily affected in CAD., Learning Points: The diagnostic criteria for crossed aphasia in dextral (CAD) are derived from clinical case studies and include aphasia, a lesion in the right hemisphere, a strong preference for using the right hand, the structural integrity of the left hemisphere and no history of brain damage during childhood.The right lentiform nucleus was found to be the most frequent anatomical substrate involved in CAD patients, consistent with our case description.Our patient experienced transcortical motor aphasia due to a stroke in the right hemisphere, adding to the evidence that in CAD patients, deep structures are primarily affected. In contrast, in left hemispheric lesions, cortical structures seem to be the main culprits., Competing Interests: Conflicts of Interests: The Authors declare that there are no competing interests., (© EFIM 2024.)

In right-handed individuals, aphasia resulting from right hemisphere damage is termed crossed aphasia and has a very low occurrence rate. Additionally, aphasia due to thalamic lesions often involves hemorrhage, with infarction cases less frequently reported. We present the case of an 81-year-old right-handed female who developed aphasia due to a right thalamic infarction. She exhibited characteristics typical of thalamic aphasia observed in left thalamic lesions. Furthermore, jargon agraphia manifested during writing tasks. This may suggest disinhibition of the left hemisphere writing motor memory by the right hemisphere language function., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Takahashi et al.)

Although, both neurological examination and neuroimaging represent the main methods for the anatomical localization of lesions in stroke patients, atypical anatomical-functional representation of cortical lateralized syndromes can occur. Herein, we introduce three cases of atypical representation of left hemispheric syndromes with right hemispheric lesions and we explore the possible mechanisms underlying such disorders and their clinical implications.

Background: Super-refractory status epilepticus (SRSE) is a critical neurological condition with a high mortality rate. There are only limited data to direct the treatment in SRSE, and surgery has been reported to successfully stop SRSE. We present a case of recurrent SRSE treated with urgent right temporal lobectomy in a right-handed woman which potentially saved her life but resulted in crossed sensory aphasia. Case Description: A 61-year-old woman with a recent episode of prolonged focal SRSE due to right frontotemporal meningioma and hyperkalemia was admitted for recurrence of seizures that evolved to SRSE despite aggressive treatment with multiple fosphenytoin antiepileptic drugs (AEDs) and anesthetics. The patient underwent a right temporal lobectomy to remove the encephalomalacic and gliotic tissue around the meningioma that had been resected during a previous admission. Postoperatively the patient had a protracted course with modest improvement after stepwise reduction in her AEDs; however, her recovery unveiled a severe crossed aphasia. Conclusion: Resective surgery is an effective treatment option in the treatment of SRSE, although the recovery period can be protracted. Crossed aphasia after right temporal lobectomy should be considered in patients where it is not possible to complete a presurgical evaluation of higher cortical functions.

Objectives: To characterize patterns of language lateralization in a right-handed woman with nonfluent/agrammatic primary progressive aphasia (nfvPPA) clinical picture despite showing a prevalent right-sided brain damage. Methods: We report a case of a 58-year-old woman with nfvPPA diagnosis (age at onset = 55) previously described as a crossed aphasia case with progranulin mutation. At 2 years from the first visit, patient underwent 3DT1-weighted and a task-based functional MRI (fMRI). During the fMRI task, she was asked to perform a letter fluency test as the task of interest and to count forward as the control condition. Image processing and data analysis were performed using SPM12 and the effect of each task was tested at p < 0.05 FWE corrected. Results: The structural MRI confirmed a widespread right fronto-temporal atrophy mainly involving the right inferior frontal gyrus. During the letter fluency task, we observed an increased activation centered at the right inferior orbitofrontal gyrus and right middle frontal gyrus. By reducing the threshold, the pattern of functional activation was still dramatically prevalent at the right side. Conclusions: We provided evidence of the right language lateralization in a previously suspected crossed nfvPPA. Despite the long disease duration and the large amount of atrophy at the right side, there was no fMRI evidence of a left-hemisphere contribution to language function. We might speculate that compensatory effects do not appear when the premorbid language lateralization is purely right. The investigation of the underlying functional brain substrates in crossed nfvPPA cases may help understanding disease vulnerability in these neurodegenerative conditions. [ABSTRACT FROM AUTHOR]

Background: Primary progressive aphasia (PPA) is a degenerative disease that presents as progressive decline of language ability with preservation of other cognitive functions in the early stages. Three subtypes of PPA are known: progressive nonfluent aphasia, semantic dementia, and logopenic aphasia (LPA). Patients and Methods: We report the case of a 77-year-old patient with PPA whose clinical findings did not correspond to the three subtypes but mainly fit LPA. Unlike other LPA patients, however, this patient showed a right hemisphere predominant glucose hypometabolism and tau accumulation and a left hemisphere predominant amyloid deposition. The right-handed patient presented with comprehension difficulty followed by problems naming familiar objects. This isolated language problem had deteriorated rapidly for 2 years, followed by memory difficulties and impairment of daily activities. Using a Korean version of the Western Aphasia Battery, aphasia was consistent with a severe form of Wernicke's aphasia. According to the brain magnetic resonance imaging and 18F-fludeoxyglucose positron emission tomography results, right hemisphere atrophy and hypometabolism, more predominant on the right hemisphere than the left, were apparent despite the fact that Edinburgh Handedness Questionnaire scores indicated strong right-handedness. On Pittsburgh compound B-PET, amyloid accumulation was asymmetrical with the left hemisphere being more predominant than the right, whereas 18F-T807-PET showed a right dominant tau accumulation. Conclusions: This is the first report of atypical PPA, in which the patient exhibited crossed aphasia and asymmetrical amyloid accumulation.

Background: Crossed aphasia, a language disturbance in right-handed individuals secondary to a right hemisphere lesion, is rare, occurring in only l-2% of brain-lesioned patients. The precise neurological mechanisms of crossed aphasia are still unknown, and follow-up studies in the long term of language function are sparse. Aims: We describe a detailed follow-up evaluation of language function and resting brain glucose metabolism in a well-defined crossed aphasia patient after right middle cerebral artery (MCA) infarction. Methods & Procedures: A 49-year-old man was referred for the treatment of 3-week history of aphasia after right MCA infarction. He indicated a strong right-handed preference confirmed by the Edinburgh Handedness Questionnaire, and his family members are all right handed. There was no history of developmental delay or learning disability in childhood or previous neurological disease. Formal language evaluation was carried out in the subacute phase (3 weeks after onset) and the late phase (5 and 24 months after onset) with the Korean version of Western Aphasia Battery. He received 40-min sessions of conventional speech and language therapy by a qualified therapist of comparable experience, three times a week. The serial F-18 fluorodeoxyglucose positron emission tomography (FDG PET) scan was performed on 3 weeks and 24 months after onset, respectively. Subtraction PET imaging between baseline and follow-up evaluation was conducted with coregistration with the patient’s magnetic resonance imaging. Outcomes & Results: In the initial evaluation, his aphasia was categorized as Broca’s aphasia [aphasia quotients (AQs) 50.4, language quotients (LQs) 49.8]. Four months after the initial evaluation, the function of spontaneous speech, repetition, naming, and reading significantly improved, with a relatively moderate progress of comprehension (AQ 83.5, LQ 78.1). At 2-year follow-up, the function of spontaneous speech, repetition, naming, reading, and writing improved, but the comprehension revealed impairment with minimal improvement (AQ 88.9, LQ 86.8). The result revealed that the 20% increased area of F-18 FDG uptake in the subtraction PET image corresponded to the right basal ganglia, the right medial temporal lobe, both occipital lobes, and the left cerebellum. Conclusions: Our case showed long-term recovery of brain glucose metabolism and language function in a patient with mirror image crossed aphasia. The restoration of perilesional brain function and diaschisis possibly contributed to the recovery of the crossed aphasia. [ABSTRACT FROM AUTHOR]

Objective: Crossed aphasia (CA), usually referred to as an acquired language disturbance, is caused by a lesion in the cerebral hemisphere ipsilateral to the dominant hand, and the exact mechanism is not clear. The development of handedness is influenced by education and training and the impact of habitualization, while language is more susceptible to the impact of speech habits, and it is not absolutely accurate to judge cerebral language dominance by the degree of hand preference.Methods: We describe a case of CA after right hemispheric stroke in a right-handed patient with atypical language dominance and attempt to analyze the mechanism of CA based on functional imaging methods, including arterial spin labeling (ASL) and positron emission tomography/magnetic resonance imaging (PET-MRI).Results: Brain MRI at 24 h after admission showed a large cerebral infarction in the right cerebral hemisphere, including the posteroinferior part of Broca’s area in the right frontal lobe, the right temporal lobe, and the right occipital lobe. The patient exhibited a non-fluent aphasia on a standard language test (the Aphasia Battery of Chinese [ABC]) performed on the 7th day after onset. Thus, atypical language dominance was suspected. One week after admission, ASL imaging showed high perfusion in the infarct core zone and low perfusion in the left cerebellar hemisphere. Two months later, PET/MRI demonstrated low metabolism in the posterior frontal lobe, temporal lobe, temporal occipital junction area, and the right basal ganglia.Conclusion: The findings suggest that the patient has right-sided cerebral language dominance, or that both hemispheres have linguistic functions. Not all patients show linguistic capabilities on the side opposite hand preference. The language dominance should be predicted by a combination of clinical manifestations and functional imaging techniques. [ABSTRACT FROM AUTHOR]

Donepezil (DP), a cognitive-enhancing drug targeting the cholinergic system, combined with massed sentence repetition training augmented and speeded up recovery of speech production deficits in patients with chronic conduction aphasia and extensive left hemisphere infarctions (Berthier et al., 2014). Nevertheless, a still unsettled question is whether such improvements correlate with restorative structural changes in gray matter and white matter pathways mediating speech production. In the present study, we used pharmacological magnetic resonance imaging to study treatment-induced brain changes in gray matter and white matter tracts in a right-handed male with chronic conduction aphasia and a right subcortical lesion (crossed aphasia). A single-patient, open-label multiple-baseline design incorporating two different treatments and two post-treatment evaluations was used. The patient received an initial dose of DP (5 mg/day) which was maintained during 4 weeks and then titrated up to 10 mg/day and administered alone (without aphasia therapy) during 8 weeks (Endpoint 1). Thereafter, the drug was combined with an audiovisual repetition-imitation therapy (Look-Listen-Repeat, LLR) during 3 months (Endpoint 2). Language evaluations, diffusion weighted imaging (DWI), and voxel-based morphometry (VBM) were performed at baseline and at both endpoints in JAM and once in 21 healthy control males. Treatment with DP alone and combined with LLR therapy induced marked improvement in aphasia and communication deficits as well as in selected measures of connected speech production, and phrase repetition. The obtained gains in speech production remained well-above baseline scores even 4 months after ending combined therapy. Longitudinal DWI showed structural plasticity in the right frontal aslant tract and direct segment of the arcuate fasciculus with both interventions. VBM revealed no structural changes in other white matter tracts nor in cortical areas linked by these tracts. In conclusion, cholinergic potentiation alone and combined with a model-based aphasia therapy improved language deficits by promoting structural plastic changes in right white matter tracts.

Donepezil (DP), a cognitive-enhancing drug targeting the cholinergic system, combined with massed sentence repetition training augmented and speeded up recovery of speech production deficits in patients with chronic conduction aphasia and extensive left hemisphere infarctions (Berthier et al., 2014). Nevertheless, a still unsettled question is whether such improvements correlate with restorative structural changes in gray matter and white matter pathways mediating speech production. In the present study, we used pharmacological magnetic resonance imaging to study treatment-induced brain changes in gray matter and white matter tracts in a right-handed male with chronic conduction aphasia and a right subcortical lesion (crossed aphasia). A single-patient, open-label multiple-baseline design incorporating two different treatments and two post-treatment evaluations was used. The patient received an initial dose of DP (5 mg/day) which was maintained during 4 weeks and then titrated up to 10 mg/day and administered alone (without aphasia therapy) during 8 weeks (Endpoint 1). Thereafter, the drug was combined with an audiovisual repetition-imitation therapy (Look-Listen-Repeat, LLR) during 3 months (Endpoint 2). Language evaluations, diffusion weighted imaging (DWI), and voxel-based morphometry (VBM) were performed at baseline and at both endpoints in JAM and once in 21 healthy control males. Treatment with DP alone and combined with LLR therapy induced marked improvement in aphasia and communication deficits as well as in selected measures of connected speech production, and phrase repetition. The obtained gains in speech production remaine well-above baseline scores even 4 months after ending combined therapy. Longitudinal DWI showed structural plasticity in the right frontal aslant tract and direct segment of the arcuate fasciculus with both interventions. VBM revealed no structural changes in other white matter tracts nor in cortical areas linked by these tracts. In conclusion, cholinergic potentiation alone and combined with a model-based aphasia therapy improved language deficits by promoting structural plastic changes in right white matter tracts. [ABSTRACT FROM AUTHOR]

Apraxia of speech (AOS) is a rare, but well-defined motor speech disorder. It is characterized by irregular articulatory errors, attempts of self-correction and persistent prosodic abnormalities. Similar to aphasia, AOS is also localized to the dominant cerebral hemisphere. We report a case of Crossed Aphasia with AOS in a 48-year-old right-handed man due to an ischemic infarct in right cerebral hemisphere.

We report a patient presenting with crossed aphasia following infarction in the territory of the right anterior cerebral artery (ACA). A right-handed 68-year-old woman without a history of correction had acute disturbance of consciousness, left hemiparesis predominant in the lower extremity, speech disorder and left unilateral spatial neglect during the admission due to hypertensive emergency. No other family member was left-handed. MRI of the head revealed acute phase infarction in the territory of the right ACA: mesial frontal lobe including the supplementary motor area, anterior cingulate gyrus, and the corpus callosum. Language symptoms in the subacute phase included difficulty in initiation, slow speech rate, loss of intonation and phonetic paraphasia, and accompanying errors in comprehension, repetition, reading, and writing letters. These symptoms suggested "anomalous" type crossed aphasia. No limb apraxia, construction disorder or left unilateral spatial neglect was observed in this period. Only a few cases of crossed aphasia due to infarction in the territory of the ACA have been reported so far. However, language and concomitant symptoms differs, depending on each case, suggesting a difference in individual cerebral lateralization.

Resumen La afasia progresiva primaria es un síndrome clínico secundario a la neurodegeneración de las áreas y redes neuronales involucradas en el lenguaje, habitualmente en el hemisferio izquierdo. El término «afasia cruzada» se refiere a una alteración del lenguaje como consecuencia de una lesión del hemisferio cerebral ipsilateral a la mano dominante. Presentamos el caso de una mujer diestra de 75 años con afasia progresiva primaria logopénica, con dificultad para encontrar palabras, de 2 años de evolución. La 18 F-FDG PET/TC mostró un hipometabolismo temporoparietal derecho. Se realizó una RM funcional para caracterizar patrones de lateralización del lenguaje. Se observó un patrón de activación similar en ambos hemisferios y una menor activación de la esperada en el giro frontal inferior bilateral. Estos hallazgos apoyan que la afasia progresiva primaria logopénica no debería considerarse como una afectación de inicio en el hemisferio izquierdo, sino un síndrome caracterizado por una neurodegeneración asimétrica con preferencia por áreas y redes neuronales implicadas en el lenguaje. Primary progressive aphasia is a clinical syndrome caused by a neurodegeneration of areas and neural networks involved in language, usually in the left hemisphere. The term “crossed aphasia” denotes an acquired language dysfunction caused by a lesion in the hemisphere ipsilateral to the dominant hand. A case is presented on a 75-year-old right-handed woman with a logopenic variant of primary progressive aphasia with word-finding difficulties of 2 years onset. The 18 F-FDG PET/CT showed right temporoparietal hypometabolism. A functional MRI scan was performed during a verb naming task in order to characterise language lateralisation patterns. A similar activation pattern was observed in both hemispheres, with less activation than expected in bilateral inferior frontal gyrus. These findings support that logopenic variant of primary progressive aphasia should not be considered as a neurodegeneration starting in the left brain hemisphere, but as a syndrome characterised by asymmetric neurodegeneration of brain regions and neural networks involved in language. [ABSTRACT FROM AUTHOR]

Few studies have investigated language recovery patterns and the mechanisms of crossed bilingual aphasia following a subcortical stroke. In particular, Korean-Japanese crossed bilingual aphasia has not been reported. A 47-year-old, right-handed man was diagnosed with an extensive right basal ganglia hemorrhage. He was bilingual, fluent in both Korean and Japanese. After his stroke, the patient presented with crossed aphasia. We investigated changes in the Korean (L1) and Japanese (L2) language recovery patterns. Both Korean and Japanese versions of the Western Aphasia Battery (WAB) were completed one month after the stroke, and functional magnetic resonance imaging (fMRI) was performed using picture-naming tasks. The WAB showed a paradoxical pattern of bilingual aphasia, with an aphasia quotient (AQ) of 32 for Korean and 50.6 for Japanese, with Broca’s aphasia. The patient scored better in the Japanese version of all domains of the tests. The fMRI study showed left lateralized activation in both language tasks, especially in the inferior frontal gyrus. After six months of language therapy targeting L1, the Korean-WAB score improved significantly, while the Japanese-WAB score showed slight improvement. In this case, the subcortical lesion contributed to crossed bilingual aphasia more highly affecting L1 due to loss of the cortico-subcortical control mechanism in the dominant hemisphere. The paradoxical pattern of bilingual aphasia disappeared after lengthy language therapy targeting L1, and the therapy effect did not transfer to L2. Language recovery in L1 might have been accomplished by reintegrating language networks, including the contralesional language homologue area in the left hemisphere. [ABSTRACT FROM PUBLISHER]

Introduction Considering the prevailing view of right hemisphere’s limited capacity for lexical-semantics and its lack of phonological capacity (Coslet & Saffran, 1998), it is quite predictable that writing difficulties in right hemisphere damaged (RHD) is mainly attributed to impairment in peripheral mechanism involved in visual and/or kinesthetic information processing. This type of peripheral agraphia has been termed as ‘‘spatial agraphia’’ or ‘‘afferent dysgraphia’’. (Ardila, & Rosselli, 1993; Croisile, & Hibert, 1998; Cubelli, Guiducci, & Consolmagno, 2000; Margolin & Binder, 1984; Seki et al., 1998). However, under unusual circumstances such as damage to the left hemisphere, the RH may develop some capacity to write and spell (Weekes, 1995). A subgroup of RHD patients with symptoms of crossed aphasia (CA) may also display deficits in written language (Basso et. al, 1985). However, cognitive model-based description of crossed dysgraphia (CD) is seldom seen in the literature, with one single exception (Gonzales-Rothi, Roeltgen, & Kooistra, 1987). Currently, it is difficult to predict to what extent RHD in general, and CA in particular, will result in impairments of the central components of writing/spelling. The hypothesis of limited lexical-semantic and phonological capacity of the right hemisphere, as mentioned earlier, will predict that the RHD patients will not experience significant problems in the central linguistic components of writing/spelling. The current study reports on a case of CD in a RHD elderly adult who has evidenced symptoms of impairments of central components of writing/spelling. Method Subject. SE, a 69-year-old right-handed female had a sudden onset of speechlessness and left-sided hemiplegia. A repeat CT scan revealed lesions in the head of caudate and putamen of the right hemisphere. The left hemisphere was spared. In the acute stage, SE’s communication status was characterized by global aphasia. In the sub-acute stage, global aphasia began to resolve. At one month post-onset, SE’s language impairment resembled the profile of Broca’s aphasia. In addition, SE’s speech was characterized by moderate to severe apraxia of speech. Experimental tasks. SE was tested on several subtests of reading and writing part of the Psycholinguistic Assessment of Language Processing (PALPA) in Aphasia. (Kay, Lesser, & Coltheart, 1992). These sub-tests have examined the effects of several independent variables including letter length, imageability and frequency, grammatical class, lexical morphology, regularity, non-words, and homophones. Results and discussion. The results of SE’s performance on these tests are summarized in Table 1. SE’s performance on the PALPA tests revealed the profile of phonological dysgraphia: Variable effect of letter lengths, better performance on high imagery/high frequency words than the low imagery/low frequency ones, responses were much better on nouns and verbs than on adjectives and functors, better performance on regularly spelled words when compared to irregular words, profoundly impaired performance on words and homophones. These results clearly establish the impairments of the central/linguistic components of writing/spelling in SE. It is hoped that the discovery of a variety of CD patterns will reinforce the view of individual differences in structural and functional brain organization in relation to language.

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.

Studies of patients with brain lesions have demonstrated that language and praxis are mediated by dissociable networks. However, language has the capacity to influence the selection of purposeful actions. The abilities to use language and to program purposeful movements are often mediated by networks that have anatomic proximity. With hemispheric injury, the diagnosis of apraxia is often confounded by the specific influence of language impairments on the ability to select and produce transitive gestures. We report a patient who illustrates this confound. This patient is a right-handed man who developed global aphasia and neglect after a right hemispheric stroke. His right hand remained deft, and when asked to produce specific transitive gestures (pantomimes), he often performed normally but did make some body part as object and perseverative errors. However, he did not demonstrate the temporal or spatial errors typical of ideomotor apraxia. He also had a perseverative agraphia. Our patient's left hemisphere praxis system appeared to be intact, and the error types demonstrated during production of transitive gestures cannot be attributed to a degradation of postural and movement (praxis) programs mediated by his left hemisphere. The praxis errors types are most consistent with a deficit in the ability to select the necessary praxis programs. Thus, our patient appeared to have dissociation between language and praxis programs that resulted in body part as object and perseverative errors. [ABSTRACT FROM AUTHOR]

Agrammatic primary progressive aphasia (PPA-G) has been known to be associated with focal brain atrophy involving the left posterior frontal and anterior insular regions. However, aphasia can also rarely result from right hemispheric lesions in right-handed patients, so-called crossed aphasia in dextrals (CAD). We report two right-handed patients with PPA-G whose 18F-fluorodeoxyglucose positron emission tomography ( 18F-FDG PET) showed hypometabolism predominantly in the right hemisphere, implicating "crossed PPA-G." [ABSTRACT FROM AUTHOR]

Abstract: There are very few longitudinal studies investigating functional recovery in aphasics affected by subcortical lesions. In addition, no longitudinal follow-up studies exist of patients with subcortical crossed aphasia. Our aim was to investigate functional recovery in two anomic patients with subcortical aphasia, one crossed aphasia and one standard, uncrossed aphasia due to a similar subcortical lesion. An er-fMRI follow-up paradigm was employed during a picture-naming task. Both patients were scanned prior to speech therapy (T0), after 3 months of anomia-specific rehabilitation (T1) and following 6 months of conventional language rehabilitation (T2). Irrespectively of lesion lateralization, fMRI data disclosed a grounding role for homologue naming-specific areas (respectively, LIFG and RIFG) in determining the progressive pattern of behavioural naming recovery throughout different disease phases. Thus, functional recovery, parallelled by improvement in behavioural naming performance, seems to be strictly related to recruitment of homologue areas in the hemisphere opposite to the aphasiogenic lesion. [Copyright &y& Elsevier]

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 non-words, 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. [ABSTRACT FROM AUTHOR]

Apraxia of speech (AOS) is a rare, but well-defined motor speech disorder. It is characterized by irregular articulatory errors, attempts of self-correction and persistent prosodic abnormalities. Similar to aphasia, AOS is also localized to the dominant cerebral hemisphere. We report a case of Crossed Aphasia with AOS in a 48-year-old right.handed man due to an ischemic infarct in right cerebral hemisphere. [ABSTRACT FROM AUTHOR]

We report a right handed patient with right middle cerebral artery infarct who recovered from aphasia and has persisting agraphia and alexia. The types of errors that he showed were similar in writing as well as reading, characterized by spelling errors that would preserve the phonological form of the target word. The sparing of language functions other than reading and writing suggests the possibility of different language functions being represented in different lobes or the possibility of differential cerebral reorganization for different functions. The co-occurrence of same type of agraphia and alexia, i.e., lexical type raises the question whether reading and writing share a common neural circuit. [ABSTRACT FROM AUTHOR]

Abstract: The occurrence of crossed aphasia as a complication after temporal lobe epilepsy surgery is extremely rare. We report the case of a 47-year-old right-handed patient with drug‐resistant mesial temporal lobe epilepsy (MTLE) who developed a transitory aphasic syndrome after a right temporal anterior lobectomy. This syndrome was characterized by anomia, poor verbal fluency, verbal perseveration, and verbal comprehension difficulties. He also showed writing difficulties, reading substitutions, and calculation task errors. The patient was regularly assessed with language tasks, and showed a spontaneous and progressive recovery of his symptoms, with remaining naming difficulties. We discuss the role that epileptogenic zone could play in cortical reorganization of the language systems. [Copyright &y& Elsevier]

Purpose: The lateralization of cognitive functions in crossed aphasia in dextrals (CAD) has been explored and compared mainly with cases of aphasia with left hemisphere damage. However, comparing the neuropsychological aspects of CAD and aphasia after right brain damage in left-handers (ARL) could potentially provide more insights into the effect of a shift in the laterality of handedness or language on other cognitive organization. Thus, this case study compared two cases of CAD and one case of ARL. Materials and Methods: The following neuropsychological measures were obtained from three aphasic patients with right brain damage (two cases of CAD and one case of ARL); language, oral and limb praxis, and nonverbal cognitive functions (visuospatial neglect and visuospatial construction). Results: All three patients showed impaired visuoconstructional abilities, whereas each patient showed a different level of performances for oral and limb praxis, and visuospatial neglect. Conclusion: Based on the analysis of these three aphasic patients' performances, we highlighted the lateralization of language, handedness, oral and limb praxis, visuospatial neglect and visuospatial constructive ability in aphasic patients with right brain damage. [ABSTRACT FROM AUTHOR]

Abstract: A 68-year-old right-handed woman with no history of brain damage or familial left-handedness was admitted to our hospital due to the acute onset of speech difficulty; her speech was nonfluent. Literal and phonological paraphasias, agrammatism and paragrammatism were observed. Brain MRI revealed an acute infarction in the right anterior cerebral artery territory, involving the right corpus callosum. Moreover, cerebral blood flow was decreased not only in the area of the right corpus callosum but also in the left fronto-temporal lobe, suggesting crossed diaschisis. This is a rare case of crossed aphasia following an infarction in the right corpus callosum. [Copyright &y& Elsevier]

ypical patterns of language activation in functional MRI (fMRI) are not unusual, particularly in patients with severe epilepsy. Still, the functional significance of these activations is under debate. We describe a case of a right-handed patient affected by drug-refractory right temporal lobe epilepsy in whom pre-surgical fMRI showed bilateral language activations, greater in the right hemisphere (RH). After surgery, a right subdural hematoma caused epileptic status and severe aphasia. This post-surgical complication of a crossed aphasia confirmed the prior fMRI findings of RH language thus stressing the value of pre-surgical fMRI evaluations, even when surgery is planned in the RH of a right-handed patient. [ABSTRACT FROM AUTHOR]

Intuition is the ability to understand immediately without conscious reasoning and is sometimes explained as a 'gut feeling' about the rightness or wrongness of a person, place, situation, temporal episode or object. In contrast, insight is the capacity to gain accurate and a deep understanding of a problem and it is often associated with movement beyond existing paradigms. Examples include Darwin, Einstein and Freud's theories of natural selection, relativity, or the unconscious; respectively. Many cultures name these concepts and acknowledge their value, and insight is recognized as particularly characteristic of eminent achievements in the arts, sciences and politics. Considerable data suggests that these two concepts are more related than distinct, and that a more distributed intuitive network may feed into a predominately right hemispheric insight-based functional neuronal architecture. The preparation and incubation stages of insight may rely on the incorporation of domain-specific automatized expertise schema associated with intuition. In this manuscript the neural networks associated with intuition and insight are reviewed. Case studies of anomalous subjects with ability-achievement discrepancies are summarized. This theoretical review proposes the prospect that atypical localization of cognitive modules may enhance intuitive and insightful functions and thereby explain individual achievement beyond that expected by conventionally measured intelligence tests. A model and theory of intuition and insight's neuroanatomical basis is proposed which could be used as a starting point for future research and better understanding of the nature of these two distinctly human and highly complex poorly understood abilities. [ABSTRACT FROM AUTHOR]

The famous Swiss writer Charles-Ferdinand Ramuz suffered a stroke at 65 years, which he called ‘the adventure’ or ‘the accident’. He developed language disturbances suggesting crossed aphasia in a right hander with left hemiparesis. This uncommon pattern allowed him to continue to write his diary and to report his disturbances, with a unique depth and precision, especially for cognitive-emotional changes. Language and motor dysfunction recovered within a few weeks, but Ramuz complained of persisting emotional flattening alternating with irritability, fatigue, depression, anxiety, and concentration difficulty, which gave him the feeling to have become another person and to be inhabited by a stranger, whom he compared with devils. Ramuz fought several months to resume his literary activity, having the impression to have lost inspiration and creativity. However, the novels he wrote less than 6 months after stroke show no stylistic changes and have been found to be of the same quality as his previous production. Ramuz even ‘used’ his stroke experience in his work, in particular in a novel depicting an old man who has a stroke and dies of it. Ramuz’s diary, with his own daily description of stroke features and consequences during acute and recovery phases, is a unique document in a writer of his importance, and provides invaluable information on subjective emotional and cognitive experience of stroke. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Crossed aphasia in dextrals (CAD) following pure subcortical lesions is rare. This study describes a right-handed patient with an ischemic lesion in the right thalamus. In the post-acute phase of the stroke, a unique combination of 'crossed thalamic aphasia' was found with left visuo-spatial neglect and constructional apraxia. On the basis of the criteria used in Mariën et al. [67], this case-report is the first reliable representative of vascular CAD following an isolated lesion in the right thalamus. Furthermore, this paper presents a detailed analysis of linguistic and cognitive impairments of 'possible' and 'reliable' subcortical CAD-cases published since 1975. Out of 25 patients with a pure subcortical lesion, nine cases were considered as 'possibly reliable or reliable'. A review of these cases reveals that: 1) demographic data are consistent with the general findings for the entire group of vascular CAD, 2) the neurolinguistic findings do not support the data in the general CAD-population with regard to a) the high prevalence of transcortical aphasia and b) the tendency towards a copresence of an oral versus written language dissociation and a 'mirror-image' lesion-aphasia profile, 3) subcortical CAD is not a transient phenomenon, 4) the lesion-aphasia correlations are not congruent with the high incidence of anomalous cases in the general CAD-population, 5) neuropsychological impairments may accompany subcortical CAD. [ABSTRACT FROM AUTHOR]

Unilateral spatial neglect (USN) is commonly observed following right hemisphere injury. Many authors suggest this is because the right hemisphere constructs the network of spatial attention. Recently, prism adaptation (PA) has been reported as a remarkable approach for USN to reconstruct space representation. b this study, a patient with right brain injury with crossed aphasia and USN showed improvement of USN following PA. Crossed aphasia refers to aphasia occuring after right brain damage in right-handers and is recognized as atypical cerebral dominance. The present results suggest that the function of spatial representation was located in the right brain of this patient and redundancy of each cortical function might have been occurring at the individual level. So we need to take care in choosing therapeutic approaches for cases with anomalous dominance. [ABSTRACT FROM AUTHOR]

Abstract: The main purpose of the present study was to learn how mathematical abilities are located and develop in the brain with respect to language. Mathematical abilities were assessed in six right-handed patients affected by aphasia following a lesion to their non-dominant hemisphere (crossed aphasia) and in two left-handed aphasics with a right-sided lesion. Acalculia, although in different degrees, was found in all cases. The type of acalculia depended on the type of aphasia, following patterns that have been previously observed in the most common aphasias resulting from left hemisphere lesions. No sign of right hemisphere or spatial acalculia (acalculia in left lateralised right-handed subjects) was detected. These results suggest that, as a rule, language and calculation share the same hemisphere. A primitive computational mechanism capable of recursion may be the precursor of both functions. [Copyright &y& Elsevier]

Aphasia is a rare sign of multiple sclerosis (MS). Several different forms of aphasia have been reported in MS. We report, to our knowledge, the first case of a MS patient with crossed aphasia during an attack. [ABSTRACT FROM AUTHOR]