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The right hemisphere of the brain is often referred to as the non-dominant hemisphere. Though this is meant to highlight the specialized role of the left hemisphere in language, the use of this term runs the risk of oversimplifying or minimizing the essential functions of the right hemisphere. There is accumulating evidence from functional MRI, clinical lesion studies, and intraoperative mapping data that implicate the right hemisphere in a diverse array of cognitive functions, including visuospatial functions, attentional processes, and social cognitive functions. Neuropsychological deficits following right hemisphere resections are well-documented, but there is a general paucity of literature focusing on how to best map these functions during awake brain surgery to minimize such deficits. To address this gap in the literature, a systematic review was conducted to examine the cognitive and emotional processes associated with the right hemisphere and the neuropsychological tasks frequently used for mapping the right hemisphere during awake brain tumor surgery. It was found that the most employed tests to assess language and speech functions in patients with lesions in the right cerebral hemisphere were the naming task and the Pyramids and Palm Trees Test (PPTT). Spatial cognition was typically evaluated using the line bisection task, while social cognition was assessed through the Reading the Mind in the Eyes (RME) test. Dual-tasking and the movement of the upper and lower limbs were the most frequently used methods to evaluate motor/sensory functions. Executive functions were typically assessed using the N-back test and Stroop test. To the best of our knowledge, this is the first comprehensive review to help provide guidance on the cognitive functions most at risk and methods to map such functions during right awake brain surgery. [ABSTRACT FROM AUTHOR]

The right hemisphere has been underestimated by being considered as the non-dominant hemisphere. However, it is involved in many functions, including movement, language, cognition, and emotion. Therefore, because lesions on this side are usually not resected under awake mapping, there is a risk of unfavorable neurological outcomes. The goal of this study is to compare the functional and oncological outcomes of awake surgery (AwS) versus surgery under general anesthesia (GA) in supratentorial right-sided gliomas. A systematic review of the literature according to PRISMA guidelines was performed up to March 2023. Four databases were screened. Primary outcome to assess was return to work (RTW). Secondary outcomes included the rate of postoperative neurological deficit, postoperative Karnofsky Performance Status (KPS) score and the extent of resection (EOR). A total of 32 articles were included with 543 patients who underwent right hemisphere tumor resection under awake surgery and 294 under general anesthesia. There were no significant differences between groups regarding age, gender, handedness, perioperative KPS, tumor location or preoperative seizures. Preoperative and long-term postoperative neurological deficits were statistically lower after AwS (p = 0.03 and p < 0.01, respectively), even though no difference was found regarding early postoperative course (p = 0.32). A subsequent analysis regarding type of postoperative impairment was performed. Severe postoperative language deficits were not different (p = 0.74), but there were fewer long-term mild motor and high-order cognitive deficits (p < 0.05) in AwS group. A higher rate of RTW (p < 0.05) was documented after AwS. The EOR was similar in both groups. Glioma resection of the right hemisphere under awake mapping is a safer procedure with a better preservation of high-order cognitive functions and a higher rate of RTW than resection under general anesthesia, despite similar EOR. [ABSTRACT FROM AUTHOR]

McGilchrist [McGilchrist, I. (2009). The master and His emissary: The divided brain and the making of the modern world. Yale University Press] argued that Western society has undergone a population-level shift from greater right hemisphere influence on cognition to increasingly greater left hemisphere influence over the past few centuries. Four historical lifestyle changes that replaced behaviours associated with right hemisphere activation with behaviours associated with left hemisphere activation may be responsible: (i) shifts from standing to sitting, (ii) from being outdoors to indoors, (iii) from communal to solitary activities, and (iv) from analogue/concrete to holistic/abstract representations. [ABSTRACT FROM AUTHOR]

The objective of this study is to present results of the rehabilitation of an individual case of an adolescent patient with early brain damage in right hemisphere and the cerebellum because of a stroke with an evolution of more than ten years without any formal treatment. The method of the individual case study was used in this research, performing a pre-and-post qualitative assessment before and after of the application of the neuropsychological rehabilitation program. The results obtained in the study allowed to point out an improvement in the functioning of functional systems for practical, ludical, graphic and verbal actions of the patient. Positive changes were obtained in the motor sphere, muscle tone and balance. The patient became more independent in his general behavior, his interests were increased, he showed a higher level of regulation, responsibility, and active participation in his day-to-day life. Neuropsychological assessment should consider the psychophysiological cause of the patient’s difficulties together with the guiding activity of psychological age. Results of such assessment lead to elaboration and application of effective programs for rehabilitation even after long periods without formal treatment. Luria’s neuropsychological theory together with the theory of psychological development represents a solid background for the assessment and organization of the rehabilitation process in cases of patients with brain damage after several years since the event.

The right hemisphere of the brain is often referred to as the non-dominant hemisphere. Though this is meant to highlight the specialized role of the left hemisphere in language, the use of this term runs the risk of oversimplifying or minimizing the essential functions of the right hemisphere. There is accumulating evidence from functional MRI, clinical lesion studies, and intraoperative mapping data that implicate the right hemisphere in a diverse array of cognitive functions, including visuospatial functions, attentional processes, and social cognitive functions. Neuropsychological deficits following right hemisphere resections are well-documented, but there is a general paucity of literature focusing on how to best map these functions during awake brain surgery to minimize such deficits. To address this gap in the literature, a systematic review was conducted to examine the cognitive and emotional processes associated with the right hemisphere and the neuropsychological tasks frequently used for mapping the right hemisphere during awake brain tumor surgery. It was found that the most employed tests to assess language and speech functions in patients with lesions in the right cerebral hemisphere were the naming task and the Pyramids and Palm Trees Test (PPTT). Spatial cognition was typically evaluated using the line bisection task, while social cognition was assessed through the Reading the Mind in the Eyes (RME) test. Dual-tasking and the movement of the upper and lower limbs were the most frequently used methods to evaluate motor/sensory functions. Executive functions were typically assessed using the N-back test and Stroop test. To the best of our knowledge, this is the first comprehensive review to help provide guidance on the cognitive functions most at risk and methods to map such functions during right awake brain surgery.Systematic Review RegistrationPROSPERO database [CRD42023483324].

It is widely known that the left half of the neocortex is responsible for speech. Given the law of asymmetry in the brain work, right-handed students of a philology department should be more successful in their academic studies. It is this logical conclusion that has been questioned and verified experimentally. The result obtained is presented in this article. The purpose of this micro study is to establish the relationship between the functional specialization of the neocortex, right-/left-handedness and academic performance of philology students completing their three-year studies of foreign languages at a classical university. The preliminary hypothesis of the study stated that the right-handed students with a dominant left hemisphere of the brain, in which, as is known, there is the speech center that actively stimulates all speech processes, should be more successful than left-handed students who do not have such an advantage. This goal setting determined the content structure of the article, consisting of a brief introduction to a lateral phenotypy, a description of methods for determining the dominance of hemispheric brain activity and the results of their use in diagnosing students, as well as establishing a correlation between the academic performance of students and their lateral phenotype. Cognitive activity is the central function of the brain; therefore, the use of the achievements of neuroscience in the educational field is an inexhaustible source of improving educational technologies. This makes the article timely and topical. The following scientific methods were used to solve the stated problems: analytical-synthetic and empirical i.e. description, explanation, generalization, as well as experimental. The results of this micro research did not validate the hypothesis: the left-handed philology students, whose dominant hemisphere does not contain the speech zone that supports all speech processes, turned out to be more successful academically in philological disciplines than the right-handed students of the same stream of study. This implies the need for broader and deeper research.

Objective: Computerized neglect tests could significantly deepen our disorder-specific knowledge by effortlessly providing additional behavioral markers that are hardly or not extractable from existing paper-and-pencil versions. This study investigated how testing format (paper versus digital), and screen size (small, medium, large) affect the Center of cancelation (CoC) in right-hemispheric stroke patients in the Letters and the Bells cancelation task. Our second objective was to determine whether a machine learning approach could reliably classify patients with and without neglect based on their search speed, search distance, and search strategy. Method: We compared the CoC measure of right hemisphere stroke patients with neglect in two cancelation tasks across different formats and display sizes. In addition, we evaluated whether three additional parameters of search behavior that became available through digitization are neglect-specific behavioral markers. Results: Patients' CoC was not affected by test format or screen size. Additional search parameters demonstrated lower search speed, increased search distance, and a more strategic search for neglect patients than for control patients without neglect. Conclusion: The CoC seems robust to both test digitization and display size adaptations. Machine learning classification based on the additional variables derived from computerized tests succeeded in distinguishing stroke patients with spatial neglect from those without. The investigated additional variables have the potential to aid in neglect diagnosis, in particular when the CoC cannot be validly assessed (e.g., when the test is not performed to completion). [ABSTRACT FROM AUTHOR]

Objectives: To identify the major complications independently associated with unfavorable outcomes in right‐sided large hemisphere infarction (RLHI) patients. Methods: We retrospectively enrolled consecutive patients admitted within 24 h with the diagnosis of RLHI. The unfavorable outcome was defined as a modified Rankin Scale score of 4–6 at 3 months. Univariate and multivariate analyses were performed to identify the major complications independently associated with 3‐month unfavorable outcomes. Results: Of the 171 cases with RLHI included, 126 (73.7%) had unfavorable outcomes at 3 months: A total of 64 (37.4%) cases died, and 62 (36.3%) lived with severe disability. Stroke‐related complications occurred in 168 (98.2%) patients during hospitalization. The five most common stroke‐related complications were pulmonary infection (75.4%), electrolyte disorder (61.4%), hypoalbuminemia (49.1%), malignant brain edema (MBE) (48.5%), and hemorrhagic transformation (48.0%). RLHI patients with unfavorable outcomes had more frequent MBE (58.7% vs. 21.4%, p <.001), pulmonary infection (86.5% vs. 42.9%, p <.001), gastrointestinal bleeding (46.8% vs. 28.6%, p =.038), electrolyte disorder (68.3% vs. 40.5%, p =.001), acute renal failure (32.5% vs. 4.8%, p <.001), and hypoalbuminemia (61.1% vs. 11.9%, p <.001) than patients with favorable outcome. Multivariate analyses suggested that only MBE (adjusted OR 4.06, 95% confidence interval [CI] 1.14–14.48, p =.031), pulmonary infection (adjusted OR 4.69, 95%CI 1.48–14.85, p =.009), and hypoalbuminemia (adjusted OR 6.58, 95%CI 1.74–24.86, p =.005) were independently associated with 3‐month unfavorable outcome in patients with RLHI. Conclusions: Most of the RLHI patients have at least one stroke‐related complication during hospitalization, and nearly three‐quarters suffered unfavorable outcomes. Only MBE, pulmonary infection, and hypoalbuminemia are independently associated with 3‐month unfavorable outcome. [ABSTRACT FROM AUTHOR]

Abstract Background The interest in the relationship between brain damage and social cognition has increased in recent years. The objectives of the present study were the following: (1) to evaluate and compare emotional facial recognition and subjective emotional experience in patients who have suffered a single ischemic stroke in the right hemisphere (RH) and in healthy people, (2) to analyze the relationship between both variables in both groups of subjects, and (3) to analyze the association between the cerebral location of the stroke and these two variables. Methods Emotional facial recognition and the subjective emotional experience of 41 patients who had suffered a single ischemic stroke in the RH and 45 volunteers without previous cerebrovascular pathology were evaluated. Results Brain damaged patients performed lower in facial emotional recognition and had a less intense subjective emotional response to social content stimuli compared to healthy subjects. Likewise, among patients with RH ischemic stroke, we observed negative associations between facial recognition of surprise and reactivity to unpleasant images, and positive associations between recognition of disgust and reactivity to pleasant images. Finally, patients with damage in the caudate nucleus of the RH presented a deficit in the recognition of happiness and sadness, and those with damage in the frontal lobe exhibited a deficit in the recognition of surprise, compared to those injured in other brain areas. Conclusions Emotional facial recognition and subjective emotional experience are affected in patients who have suffered a single ischemic stroke in the RH. Professionals caring for stroke patients should improve their understanding of the general condition of affected persons and their environment, assess for risk of depression, and facilitate their adaptation to work, family, and social environments.

Introduction. In neuropsychological practice the dichotic listening task has been widely used for more than 50 years as a valid test for determining the laterality of auditory speech asymmetry. Theoretical analysis. Most of the studies of the dichotic listening task in aphasia are characterized by small sample groups, a wide demographic features of them, lack attention to the type and aphasia severity, a size of local brain damage as well. Without taking into account these important factors it is difficult to answer to some questions: 1. whether the vector of auditory speech asymmetry is determined by the age, type and aphasia severity; 2. whether the laterality of auditory speech asymmetry affects the dynamics of aphasia recovery. The aim of the study: the connection between quantitative parameters of the dichotic listening task and the dynamics of aphasia regression. Empirical analysis. Material. The study involved patients (N = 109) with traumatic and post-stroke efferent motor (50.7 ± 10.1 years) and acoustic mnestic (54.4 ± 8.2 years) aphasia of mild and moderate severity of speech disorders. Methods. Kimura’s dichotic listening task modified by B. S. Kotik; the quantitative assessment of speech in aphasia L. S. Tsvetkova, T. V. Akhutina, N. M. Pylaeva. The speech assessment was carried out twice: before and after a 6-week course of speech rehabilitation. Results. Between efferent motor and acoustic mnestic aphasia groups the difference in the laterality of ear superiority was revealed. The efferent motor aphasia group shows the ambidextrous pattern in auditory perception. The dichotic listening task efficiency increases with a burst of the left ear productivity and vice versa with the right ear. The acoustic mnestic aphasia group presents a pronounced effect of the right ear suppression. Its productivity is significantly lower than the productivity of the left ear and the same indicator of the efferent motor aphasia group. The effectiveness of the dichotic listening task in the acoustic mnestic aphasia group does not exhibit a correlation with the parameters of productivity of the right or left ear. The aphasia groups vary in the dynamics of aphasia regression. In the acoustic mnestic aphasia group, this dynamics was 2.5 times higher than in the efferent motor aphasia group. Conclusion. The right hemisphere laterality in auditory speech perception correlates positively with the dynamics of aphasia regression. Further research should find an answer to the question of the constellations of significant factors and their hierarchical relationships that could determine the positive dynamics of recovery of aphasic disorders.

Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visuospatial processing but spared verbal competencies. Neurocognitive markers may provide confirmatory evidence for characterizing NVLD as a separate neurodevelopmental disorder. Visuospatial performance and high-density electroencephalography (EEG) were measured in 16 NLVD and in 16 typically developing (TD) children. Cortical source modeling was applied to assess resting-state functional connectivity (rs-FC) in spatial attention networks (dorsal (DAN) and ventral attention networks (VAN)) implicated in visuospatial abilities. A machine-learning approach was applied to investigate whether group membership could be predicted from rs-FC maps and if these connectivity patterns were predictive of visuospatial performance. Graph theoretical measures were applied to nodes inside each network. EEG rs-FC maps in the gamma and beta band differentiated children with and without NVLD, with increased but more diffuse and less efficient functional connections bilaterally in the NVLD group. While rs-FC of the left DAN in the gamma range predicted visuospatial scores for TD children, in the NVLD group rs-FC of the right DAN in the delta range predicted impaired visuospatial performance, confirming that NVLD is a disorder with a predominant dysfunction in right hemisphere connectivity patterns. [ABSTRACT FROM AUTHOR]

Poststroke aphasia typically results from brain damage to the left‐lateralized language network. The contribution of the right‐lateralized homologues in aphasia recovery remains equivocal. In this longitudinal observational study, we specifically investigated the role of right hemisphere structural connectome in aphasia recovery. Twenty‐two patients with aphasia after a left hemispheric stroke underwent comprehensive language assessment at the early subacute and chronic stages. A novel structural connectometry approach, using multi‐shell diffusion‐weighted MRI data collected at the early subacute stage, was used to evaluate the relationship between right hemisphere white matter connectome and language production and comprehension abilities at early subacute stage. Moreover, we evaluated the relationship between early subacute right hemisphere white matter connectome and longitudinal change in language production and comprehension abilities. All results were corrected for multiple comparisons. Connectometry analyses revealed negative associations between early subacute stage right hemisphere structural connectivity and language production, both cross‐sectionally and longitudinally (pFDR <.0125). In turn, only positive associations between right hemisphere structural connectivity and language comprehension were observed, both cross‐sectionally and longitudinally (pFDR <.0125). Interhemispheric connectivity was highly associated with comprehension scores. Our results shed light on the discordant interpretations of previous findings, by providing evidence that while some right hemisphere white matter pathways may make a maladaptive contribution to the recovery of language, other pathways support the recovery of language, especially comprehension abilities. [ABSTRACT FROM AUTHOR]

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

The various intuitive reasoning types in many cases comprise the core of students' misconceptions about concepts, procedures and phenomena that pertain to natural sciences. Some researchers support the existence of a relatively closer connection between the right hemisphere and intuitive thought, mainly due to a notably closer relation of individual intuitive cognitive processes with specific right hemisphere regions. It has been suggested that individuals show a different preference in making use of each hemisphere's cognitive capacity, a tendency which has been termed Hemisphericity or Hemisphere Preference. The purpose of the present study was to examine the association between hemispheric preference and students' misconceptions. A correlational explanatory research approach was implemented involving 100 seventh grade students from a public secondary school. Participants completed a hemispheric preference test and a misconceptions documentation tool. The results revealed that there wasn't any differentiation in the mean score of misconceptions among the students with right hemispheric dominance and those with left hemispheric dominance. These findings imply a number of things: (a) the potential types of intuitive processes, that might be activated by the students, in interpreting the biology procedures and phenomena and their total resultant effect on students' answers, probably do not have any deep connection with the right hemisphere; (b) it is also possible that students might use reflective and analytic thought more frequently than we would have expected. [ABSTRACT FROM AUTHOR]

Background and Objective: In the process of learning, interaction and organization of both the right and left hemispheres of the brain are involved. The different functions of each hemisphere and the different capacity and learning strategies show that people do not learn in the same way. Paying attention to the capabilities of both hemispheres of the brain in the learning process can lead to a brain-centered approach that, by coordinating the two hemispheres and paying attention to the capabilities of each hemisphere, can improve learning in students. Methods: The research is a descriptive-analytical cross-sectional approach that was conducted in 1998. The statistical population is 1000 students of the University of Medical Sciences and by stratified random sampling from all faculties, the number of samples was 334. The instruments used are personal information questionnaire and left hemisphere-right hemisphere questionnaire. Chi-square and Wi-Fi correlation tests were used to analyze the statistical data. Findings: The results showed that there was no statistically significant relationship between field of study, parental literacy, gender and the dominant hemisphere of the brain, but showed a significant relationship with ethnicity (P <0.043). This variable was one of the important variables in this study that due to the diversity of ethnicities in Golestan province can be considered by other researchers in future studies. Conclusion: Despite the fact that the variable of superiority of one hemisphere of the brain over another is not effective in our study, examining other aspects of the activity of the hemisphere of the brain by focusing on different ethnicities will still maintain its position. [ABSTRACT FROM AUTHOR]

Abstract Objectives To identify the major complications independently associated with unfavorable outcomes in right‐sided large hemisphere infarction (RLHI) patients. Methods We retrospectively enrolled consecutive patients admitted within 24 h with the diagnosis of RLHI. The unfavorable outcome was defined as a modified Rankin Scale score of 4–6 at 3 months. Univariate and multivariate analyses were performed to identify the major complications independently associated with 3‐month unfavorable outcomes. Results Of the 171 cases with RLHI included, 126 (73.7%) had unfavorable outcomes at 3 months: A total of 64 (37.4%) cases died, and 62 (36.3%) lived with severe disability. Stroke‐related complications occurred in 168 (98.2%) patients during hospitalization. The five most common stroke‐related complications were pulmonary infection (75.4%), electrolyte disorder (61.4%), hypoalbuminemia (49.1%), malignant brain edema (MBE) (48.5%), and hemorrhagic transformation (48.0%). RLHI patients with unfavorable outcomes had more frequent MBE (58.7% vs. 21.4%, p

Aphasia is a common consequence of stroke and repetitive transcranial magnetic stimulation (rTMS) may be a promising brain stimulation technique in the treatment of aphasia. However, there are few reports about the therapeutic effect of rTMS for Broca’s area in patients with sensory aphasia. This study reported one stroke patient with sensory aphasia who received 6 treatment sessions of low-frequency rTMS before speech and language therapy. The target area was the Broca mirror area in the right hemisphere. After treatment, the auditory comprehension of the patient improved from 46 to 112, the naming improved from 18 to 32, and the AQ improved from 34.2 to 42.6. However, the level of functional language, spontaneous speech and repetition did not show obvious improvement.

Background: The interest in the relationship between brain damage and social cognition has increased in recent years. The objectives of the present study were the following: (1) to evaluate and compare emotional facial recognition and subjective emotional experience in patients who have suffered a single ischemic stroke in the right hemisphere (RH) and in healthy people, (2) to analyze the relationship between both variables in both groups of subjects, and (3) to analyze the association between the cerebral location of the stroke and these two variables. Methods: Emotional facial recognition and the subjective emotional experience of 41 patients who had suffered a single ischemic stroke in the RH and 45 volunteers without previous cerebrovascular pathology were evaluated. Results: Brain damaged patients performed lower in facial emotional recognition and had a less intense subjective emotional response to social content stimuli compared to healthy subjects. Likewise, among patients with RH ischemic stroke, we observed negative associations between facial recognition of surprise and reactivity to unpleasant images, and positive associations between recognition of disgust and reactivity to pleasant images. Finally, patients with damage in the caudate nucleus of the RH presented a deficit in the recognition of happiness and sadness, and those with damage in the frontal lobe exhibited a deficit in the recognition of surprise, compared to those injured in other brain areas. Conclusions: Emotional facial recognition and subjective emotional experience are affected in patients who have suffered a single ischemic stroke in the RH. Professionals caring for stroke patients should improve their understanding of the general condition of affected persons and their environment, assess for risk of depression, and facilitate their adaptation to work, family, and social environments. [ABSTRACT FROM AUTHOR]

The aim of this research was to study language functions of the right hemisphere of the brain in the left hemisphere–damaged patients and compare them with healthy people. In this research, which is kind of Descriptive-Analytical, upon random sampling, two groups of the left hemisphere–damaged patients (20 men &10 women) were selected among people referred to Imam Reza Neuro Clinic, as well as 30 healthy people. Then tests of Right Hemisphere Language Collection (Brian, 1995) and test of Application Acts &Competency of Language (Mehri, 1381) were used, to compare patients' language functions with those of healthy people. The results of the research were analyzed. Analysis of data includes two parts: Descriptive Statistics and Inferential Statistics. The results of the research show that there are no significant differences between healthy and damaged people in view of sex, but there are significant differences between healthy and damaged people in 1-Metaphire test, 2-Written Metaphor test, 3-Comprehension of inferred meaning, 4-Appreciation of humor, 5-Lexical-semantic test, 6-Methapor production test, 7-Written proverb test, 8-Proverb production test, 9-Indirect speech acts test. These results indicate that abilities are not specific to the right hemisphere because people whose left hemisphere is damaged suffer from these disorders, too.

• The role of the right white matter pathways in the recovery from post-stroke aphasia is rarely understood. • The involvement of the right hemispheric neural tracts in recovery from post-stroke aphasia may be mediated by multiple factors. • Stroke stage and aphasia severity might be important factors influencing the involvement of right hemispheric homologous language pathways in the recovery from PSA, this should be comprehensively considered when analyzing the contribution of the right homologous language pathways to recovery from PSA. • Taking into account of stroke stage and aphasia severity is of great guiding significance for the clinical practice of language therapy options such as non-invasive brain stimulation techniques. The involvement of the right hemisphere, mainly the activation of the right cerebral regions, in recovery from post-stroke aphasia has been widely recognized. In contrast, the role of the right white matter pathways in the recovery from post-stroke aphasia is rarely understood. In this study, we aimed to provide a primary overview of the correlation between the structural integrity of the right hemispheric neural tracts based on the dual-stream model of language organization and recovery from post-stroke aphasia by systematically reviewing prior longitudinal interventional studies. By searching electronic databases for relevant studies according to a standard protocol, a total of 10 records (seven group studies and three case studies) including 79 participants were finally included. After comprehensively analyzing these studies and reviewing the literature, although no definite correlation was found between the right hemispheric neural tracts and recovery from post-stroke aphasia, our review provideds a new perspective for investigating the linguistic role of the right hemispheric neural tracts. This suggests that the involvement of the right hemispheric neural tracts in recovery from post-stroke aphasia may be mediated by multiple factors; thus, this topic should be comprehensively investigated in the future. [ABSTRACT FROM AUTHOR]

Cerebral hemiatrophy is a rare neurological condition, usually resulting in severe and diffuse cognitive impairment. In this paper we present a 69‐year old woman with notable congenital hemiatrophy with strikingly preserved cognitive functions. Cognitive assessment indicated that although her executive functions were found impaired, the remaining cognitive domains were relatively unaffected. We argue that this unexpected cognitive profile may be explained by anomalous hemispheric lateralization, driven by neuroplasticity along the developmental course. [ABSTRACT FROM AUTHOR]

It has been argued that dyslexia may develop in strongly left eye dominant children through learning to write using ipsilateral, right hemisphere motor pathways. New light on this theory has been cast by recent findings of atypical enhanced corpus callosum white matter in children with dyslexia, reflecting right to left hemisphere communication that is resistant to intensive remedial reading intervention. Enhanced corpus callosum white matter is consistent with uninhibited right to left hemisphere ipsilateral mirror-motor innervation, manifested as frequent mirror-letter writing errors in children with dyslexia. Delaying writing instruction until 7–8 years of age may prevent these errors and as well as the development of dyslexia. During the 7–8-year age period, visual-proprioceptive integration enables a child to mentally map whole word visual images onto kinesthetic/proprioceptive letter engrams (memory representations). Hypothetically, this process is facilitated by anterior commissure activity involving interhemispheric transfer of ipsilateral mirror-to-non mirror-motor movement. This postulate, involving delayed writing instruction pending further maturation, also receives indirect support from the remarkable proficiency leap among second graders reading Hebrew as Hebrew involves a leftward orthography in which ipsilateral right to left hemisphere innervation is uninhibited. Additionally, and more directly, normal reading comprehension for learning English among children with agenesis of the corpus callosum suggests that letter-sound decoding is not the sole route to proficient reading comprehension. In this paper, I make recommendations for obtaining empirical evidence of premature writing as a cause of dyslexia. [ABSTRACT FROM AUTHOR]

IntroductionBrain surgery in the language dominant hemisphere remains challenging due to unintended post-surgical language deficits, despite using pre-surgical functional magnetic resonance (fMRI) and intraoperative cortical stimulation. Moreover, patients are often recommended not to undergo surgery if the accompanying risk to language appears to be too high. While standard fMRI language mapping protocols may have relatively good predictive value at the group level, they remain sub-optimal on an individual level. The standard tests used typically assess lexico-semantic aspects of language, and they do not accurately reflect the complexity of language either in comprehension or production at the sentence level. Among patients who had left hemisphere language dominance we assessed which tests are best at activating language areas in the brain.MethodWe compared grammar tests (items testing word order in actives and passives, wh-subject and object questions, relativized subject and object clauses and past tense marking) with standard tests (object naming, auditory and visual responsive naming), using pre-operative fMRI. Twenty-five surgical candidates (13 females) participated in this study. Sixteen patients presented with a brain tumor, and nine with epilepsy. All participants underwent two pre-operative fMRI protocols: one including CYCLE-N grammar tests (items testing word order in actives and passives, wh-subject and object questions, relativized subject and object clauses and past tense marking); and a second one with standard fMRI tests (object naming, auditory and visual responsive naming). fMRI activations during performance in both protocols were compared at the group level, as well as in individual candidates.ResultsThe grammar tests generated more volume of activation in the left hemisphere (left/right angular gyrus, right anterior/posterior superior temporal gyrus) and identified additional language regions not shown by the standard tests (e.g., left anterior/posterior supramarginal gyrus). The standard tests produced more activation in left BA 47. Ten participants had more robust activations in the left hemisphere in the grammar tests and two in the standard tests. The grammar tests also elicited substantial activations in the right hemisphere and thus turned out to be superior at identifying both right and left hemisphere contribution to language processing.ConclusionThe grammar tests may be an important addition to the standard pre-operative fMRI testing.

[Display omitted] • The 'right hemisphere' and the 'valence' models explain emotional brain asymmetries. • From the 'valence model' derived the 'approach-avoidance hypothesis'. • The 'emotion-type hypothesis' distinguishes the basic from the social emotions. • A contrast exists between the 'schematic' and the 'conceptual' levels of emotions. • Similarities exist between the right hemisphere and the 'schematic' level of emotions. In this paper I discuss the main models that have tried to explain brain asymmetries for emotions. The first models, based on clinical observations, proposed either a general right hemisphere dominance for emotions (the'right hemisphere') model or a different specialization of the right hemisphere for negative and of the left hemisphere for positive emotions (the'valence' model). In more recent times new models, based on partly modified versions of the previous ones have been proposed. The revised version of the 'valence' model, labeled the 'approach-avoidance' model maintained that hemispheric asymmetries are not related to the valence of the emotional stimulus but to the motivational (approach vs avoidance) system that is engaged by that stimulus. On the contrary, revised versions of the 'right hemisphere' hypothesis proposed graded versions of this model, maintaining that only some kinds or some levels of emotions are clearly right lateralized. One version of these models (the'emotion type hypothesis') assumed that only elementary basic emotions should be subsumed by the right hemisphere, wheres more complex social emotions should be subtended by the left hemisphere. The other version (the 'schematic level of emotion hypothesis') assumed that the right hemisphere should subsume only the basic 'schematic' level of emotions, characterized by an automatic and unconscious processing, whereas the more propositional and conscious 'conceptual' level could be less lateralized or subsumed by the left hemisphere. This last model is supported by the obsevation that the right hemisphere reveals a modus operandi (i.e. a prevalence of the 'automatic' over the 'intentional' and of the 'unconscious' over the 'conscious' functional processing) that is typical of the 'schematic level of emotions. [ABSTRACT FROM AUTHOR]

Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visuospatial processing but spared verbal competencies. Neurocognitive markers may provide confirmatory evidence for characterizing NVLD as a separate neurodevelopmental disorder. Visuospatial performance and high-density electroencephalography (EEG) were measured in 16 NLVD and in 16 typically developing (TD) children. Cortical source modeling was applied to assess resting-state functional connectivity (rs-FC) in spatial attention networks (dorsal (DAN) and ventral attention networks (VAN)) implicated in visuospatial abilities. A machine-learning approach was applied to investigate whether group membership could be predicted from rs-FC maps and if these connectivity patterns were predictive of visuospatial performance. Graph theoretical measures were applied to nodes inside each network. EEG rs-FC maps in the gamma and beta band differentiated children with and without NVLD, with increased but more diffuse and less efficient functional connections bilaterally in the NVLD group. While rs-FC of the left DAN in the gamma range predicted visuospatial scores for TD children, in the NVLD group rs-FC of the right DAN in the delta range predicted impaired visuospatial performance, confirming that NVLD is a disorder with a predominant dysfunction in right hemisphere connectivity patterns.

Objectives: Mental fatigue, 'brain fog', and difficulties maintaining engagement are commonly reported issues in a range of neurological and psychiatric conditions. Traditional sustained attention tasks commonly measure this capacity as the ability to detect target stimuli based on sensory features in the auditory or visual domains. However, with this approach, discrete target stimuli may exogenously capture attention to aid detection, thereby masking deficits in the ability to endogenously sustain attention over time. Methods: To address this, we developed the Continuous Temporal Expectancy Task (CTET) where individuals continuously monitor a stream of patterned stimuli alternating at a fixed temporal interval (690 ms) and detect an infrequently occurring target stimulus defined by a prolonged temporal duration (1020 ms or longer). As such, sensory properties of target and non-target stimuli are perceptually identical and differ only in temporal duration. Using the CTET, we assessed stroke survivors with unilateral right hemisphere damage (N = 14), a cohort in which sustained attention deficits have been extensively reported. Results: Stroke survivors had overall lower target detection accuracy compared with neurologically healthy age-matched older controls (N = 18). Critically, stroke survivors performance was characterised by significantly steeper within-block performance decrements, which occurred within short temporal windows (˜3 ½ min), and were restored by the break periods between blocks. Conclusions: These findings suggest that continuous temporal monitoring taxes sustained attention processes to capture clinical deficits in this capacity over time, and outline a precise measure of the endogenous processes hypothesised to underpin sustained attention deficits following right hemisphere stroke. [ABSTRACT FROM AUTHOR]

Language is a cognitive function that is asymmetrically distributed across both hemispheres, with left dominance for most linguistic operations. One key question of interest in cognitive neuroscience studies is related to the contribution of both hemispheres in bilingualism. Previous work shows a difference of both hemispheres for auditory processing of emotional and non-emotional words in bilinguals and monolinguals. In this study, we examined the differences between both hemispheres in the processing of emotional and non-emotional words of mother tongue language and foreign language. Sixty university students with Persian mother tongue and English as their second language were included. Differences between hemispheres were compared using the dichotic listening test. We tested the effect of hemisphere, language and emotion and their interaction. The right ear (associated with the left hemisphere) showed an advantage for the processing of all words in the first language, and positive words in the second language. Overall, our findings support previous studies reporting left-hemispheric dominance in late bilinguals for processing auditory stimuli. [ABSTRACT FROM AUTHOR]

The role of the right hemisphere (RH) in post-stroke aphasia (PSA) has not been completely understood. In general, the language alterations in PSA are normally evaluated from the perspective of the language processing models developed from Western languages such as English. However, the successful application of the models for assessing Chinese-language functions in patients with PSA has not been reported. In this study, the features of specific language-related lesion distribution and early variations of structure in RH in Chinese patients with PSA were investigated. Forty-two aphasic patients (female: 13, male: 29, mean age: 58 ± 12 years) with left hemisphere (LH) injury between 1 and 6 months after stroke were included. The morphological characteristics, both at the levels of gray matter (GM) and white matter (WM), were quantified by 3T multiparametric brain MRI. The Fridriksson et al.'s dual-stream model was used to compare language-related lesion regions. Voxel-based lesion-symptom mapping (VLSM) analysis has been performed. Our results showed that lesions in the precentral, superior frontal, middle frontal, and postcentral gyri were responsible for both the production and comprehension dysfunction of Chinese patients with PSA and were quite different from the lesions described by using the dual-stream model of Fridriksson et al. Furthermore, gray matter volume (GMV) was found significantly decreased in RH, and WM integrity was disturbed in RH after LH injury in Chinese patients with PSA. The different lesion patterns between Chinese patients with PSA and English-speaking patients with PSA may indicate that the dual-stream model of Fridriksson et al. is not suitable for the assessment of Chinese-language functions in Chinese patients with PSA in subacute phase of recovery. Moreover, decreased structural integrity in RH was found in Chinese patients with PSA. [ABSTRACT FROM AUTHOR]

Background: Cognitive-communication disorder (CCD) results from the association of language and cognition impairment that may follow right hemisphere (RH) damage and impair the quality of life of affected persons. Objective: We studied a set of 1,625 narratives produced by a cohort of 125 individuals (50 with a single right vascular lesion in the MCA territory and 75 cognitively healthy controls) using a task of picture-based discourse production. Discourse production was analyzed in its macro-and microlinguistic aspects to characterize better the linguistic mechanisms underlying RH patients' performance. Results: The RH group produced more words and elocutions than controls, with a lower rate of informational content and a higher percentage of global coherence errors (all p-values

Several mechanisms have been attributed to post-stroke loss and recovery of language functions. However, the significance and timing of domain-general and homotopic right-hemispheric activation is controversial. We aimed to examine the effect of left-hemispheric lesion location and time post-stroke on right-hemispheric activation. Voxel-based lesion analyses were informed by auditory language-related fMRI activation of 71 patients with left middle cerebral artery stroke examined longitudinally in the acute, subacute and early chronic phase. Language activation was determined in several right-hemispheric regions of interest and served as regressor of interest for voxel-based lesion analyses. We found that an acute to chronic increase of language activation in the right supplementary motor area was associated with lesions to the left extreme capsule as part of the ventral language pathway. Importantly, this activation increase correlated significantly with improvement of out-of-scanner comprehension abilities. We interpret our findings in terms of successful domain-general compensation in patients with critical left frontotemporal disconnection due to damage to the ventral language pathway but relatively spared cortical language areas.

The role of the right hemisphere (RH) in post-stroke aphasia (PSA) has not been completely understood. In general, the language alterations in PSA are normally evaluated from the perspective of the language processing models developed from Western languages such as English. However, the successful application of the models for assessing Chinese-language functions in patients with PSA has not been reported. In this study, the features of specific language-related lesion distribution and early variations of structure in RH in Chinese patients with PSA were investigated. Forty-two aphasic patients (female: 13, male: 29, mean age: 58 ± 12 years) with left hemisphere (LH) injury between 1 and 6 months after stroke were included. The morphological characteristics, both at the levels of gray matter (GM) and white matter (WM), were quantified by 3T multiparametric brain MRI. The Fridriksson et al.’s dual-stream model was used to compare language-related lesion regions. Voxel-based lesion-symptom mapping (VLSM) analysis has been performed. Our results showed that lesions in the precentral, superior frontal, middle frontal, and postcentral gyri were responsible for both the production and comprehension dysfunction of Chinese patients with PSA and were quite different from the lesions described by using the dual-stream model of Fridriksson et al. Furthermore, gray matter volume (GMV) was found significantly decreased in RH, and WM integrity was disturbed in RH after LH injury in Chinese patients with PSA. The different lesion patterns between Chinese patients with PSA and English-speaking patients with PSA may indicate that the dual-stream model of Fridriksson et al. is not suitable for the assessment of Chinese-language functions in Chinese patients with PSA in subacute phase of recovery. Moreover, decreased structural integrity in RH was found in Chinese patients with PSA.

The neurotypical brain is characterized by left hemisphere lateralization for most language processing. However, the right hemisphere plays a crucial part when it is required to bring together seemingly unrelated concepts into meaningful expressions, such as in the case of novel metaphors (unfamiliar figurative expressions). The aim of the current study was to test whether it is possible to enhance novel metaphor comprehension through an easy, efficient, and non-invasive method – intentional contraction of the left hand's muscles, to activate the motor and sensory areas in the contralateral hemisphere. One hundred eighteen neurotypical participants were asked to perform a semantic judgment task involving two-word expressions of four types: literal, conventional metaphors, novel metaphors, or unrelated, while squeezing a rubber ball with their right hand, left hand, or not at all. Results demonstrated that left-hand contraction improved novel metaphor comprehension, as participants were more accurate and quicker in judging them to be meaningful. The findings of the present work provide a simple and efficient method for boosting right hemisphere activation, which can be used to improve metaphoric language comprehension. This method can aid several populations in which right hemisphere function is not fully established, and who struggle with processing figurative language, such as adolescents and individuals on the autistic spectrum. [ABSTRACT FROM AUTHOR]

This article offers a synthesis of practice; a conceptual integration of theory-informed right brain (RB) to RB (Schore, 2012), body-to-body, somatic and relational practice, interfaced with affect regulation theory and attachment repair. It exemplifies the diverse potential of right hemispheric processing and explores and explains the theoretical underpinnings of this body-centered or somatic practice, showcasing the body as a portal to the unconscious, and to the immobilized relational material that hinders the psyche and dysregulates the body. Through a composite clinical excerpt, I present an in-session experience of my integrative practice, a multi-layered rendering of the therapist's internal clinical experience, which identifies layers of tracking the body in practice. [ABSTRACT FROM AUTHOR]