Cerebral Hemispheres Research Articles

CSF Parvalbumin Levels at Multiple Sclerosis Diagnosis Predict Future Worse Cognition, Physical Disability, Fatigue, and Gray Matter Damage.

Cognitive impairment (CI) in multiple sclerosis (MS) is frequent and determined by a complex interplay between inflammatory and neurodegenerative processes. We aimed to investigate whether CSF parvalbumin (PVALB), measured at the time of diagnosis, may have a prognostic role in patients with MS. In this cohort study, CSF analysis of PVALB and Nf-L levels was performed on all patients at diagnosis (T0) and combined with physical, cognitive, and MRI assessment after an average of 4 years of follow-up (T4) from diagnosis. Cognitive performance was evaluated with a comprehensive neuropsychologic battery: both global (cognitively normal, CN, mildly CI, mCI, and severely CI, sCI) and domain cognitive status (normal/impaired in memory, attention/information processing speed, and executive functions) were considered. Cortical thickness and gray matter volume data were acquired using 3T MRI scanner. A total of 72 patients with MS were included. At diagnosis, PVALB levels were higher in those patients who showed a worsening physical disability after 4 years of follow-up (p = 0.011). CSF PVALB levels were higher in sCI patients than in CN (p = 0.033). Moreover, higher PVALB levels significantly correlated with worse global cognitive (p = 0.024) and memory functioning (p = 0.044). A preliminary clinical threshold for PVALB levels at diagnosis was proposed (2.57 ng/mL), which maximizes the risk of showing CI (in particular, sCI) at follow-up, with a sensitivity of 91% (specificity 30%). No significant results were found for these associations with Nf-L. In addition, patients with higher levels of PVALB at diagnosis showed higher cognitive (p = 0.024) and global fatigue (p = 0.043) at follow-up. Finally, higher PVALB levels also correlated significantly with more pronounced CTh/volume at T4 in the inferior frontal gyrus (p = 0.044), postcentral gyrus (p = 0.025), frontal pole (p = 0.042), transverse temporal gyrus (p = 0.008), and cerebellar cortex (p = 0.041) and higher atrophy (change T0-T4) in the right thalamus (p = 0.038), pericalcarine cortex (p = 0.009), lingual gyrus (p = 0.045), and medial frontal gyrus (p = 0.028). The significant association found between parvalbumin levels in the CSF at diagnosis and cognitive, clinical, and neuroradiologic worsening after 4 years of follow-up support the idea that parvalbumin, in addition to Nf-L, might represent a new potential prognostic biomarker, reflecting MS neurodegenerative processes occurring since early disease stages.

Cortical and Subcortical Substrates of Working Memory in the Right Hemisphere: A Connectome-Based Lesion-Symptom Mapping Study

Working Memory (WM) is a cognitive system whose crucial role is to temporarily hold and manipulate information. Early studies suggest that verbal WM is typically associated with left hemisphere (LH) brain regions, while the processing of visuospatial information in WM more specifically depends on the right hemisphere (RH). However, recent evidence suggests a more complex network involving both hemispheres' prefrontal and posterior parietal cortices in these processes. Unfortunately, previous lesion studies often examined only one modality (either verbal, or visuospatial) or one hemisphere, which limits the possible conclusions regarding non-lateralized hemispheric involvement. Using connectome-based lesion-symptom mapping on a large sample of patients with left (LBD) and right (RBD) focal brain damage, we examined whether gray matter damage and white matter disconnections predict deficits of WM updating in an N-back task. Patients were examined with two WM tasks that differed regarding modality (verbal, spatial) and cognitive load (1-back, 2-back). Behavioral outcomes indicated that RBD patients showed significant deficits in WM updating, regardless of task modality or load. This observation was supported by whole-brain voxel-based analysis, revealing associations between WM deficits and gray matter clusters in the RH. Specifically, damage to the right lateral frontal cortex including the brain region homologous to Broca’s area was associated with verbal WM deficits, while damage to the right inferior parietal lobe and posterior temporal cortex predicted spatial WM deficits. Additionally, white matter analyses identified severely impacted tracts in the RH, predicting deficits in both verbal and spatial WM. Our findings suggest that the mental manipulation of both verbal and visuospatial information in WM updating relies on the integrity of the RH, irrespective of the specific type of information held in mind.

Recording of Local Field Potential from Both Hemispheres of the Mouse Brain

Recording of Local Field Potential from Both Hemispheres of the Mouse Brain

Distinguishing clinical and imaging characteristics of primary central nervous system lymphoma from high-grade glioma and metastatic brain tumors.

The purpose of this retrospective analysis was to evaluate the clinical presentations, radiological characteristics, patient outcomes, and therapeutic approaches among individuals diagnosed with primary central nervous system lymphoma (PCNSL), high-grade glioma (HGG), and metastatic brain tumors (METS). We assembled a cohort of brain tumor patients from two medical centers, with two oncologists independently reviewing their clinical profiles. A retrospective examination of 87 PCNSL, 87 HGG, and 71 METS cases was performed to assess the aforementioned parameters. Notable variations were identified in the incidence of epileptic seizures and cognitive impairments between PCNSL and METS patients. Cerebral hemisphere involvement was predominantly observed in HGG and METS cases. PCNSL cases exhibited a higher likelihood of multiple lesions, whereas HGG showed a greater tendency for recurrence. The median survival times were established at 24.3months for PCNSL, 44.5months for HGG, and 27.1months for METS patients. In PCNSL cases, the number of lesions was identified as a significant predictor of mortality (P = 0.008). Our findings highlight the importance of clinical and imaging features in diagnosing PCNSL, which may present distinct features compared to HGG and METS.

Interindividual Similarity of the Spatial Organization of the EEG: an Ontogenetic Study

In this study took part 39 adult subjects, 28 children 12 years old, 21 children 8–9 years old, 26 children 5–6 years old and 19 newborns. In each age group, the coefficient of interindividual similarity (CIS) of the spatial organisation of the electroencephalogram (EEG) was calculated using Pearson's crosscorrelation algorithm. Results reveal high level of interindividual similarity of spatial structure of EEG distant connections. Both in adults and children CIS exceeded 0.80. In women, compared with men, a significantly higher level of interindividual similarity of the spatial organization of the EEG was revealed for all studied combinations of EEG connections. The obtained data shows that relative stability in ontogenesis of the spatial structure of dynamic activity of the cortex is apparently provided mainly through determined by a genotype distant intra- and interhemispheric interconnections that forming certain morfofunctional “skeleton” of neocortex. The functionally specific interactions realizable across more plastic “local chains” of near intercortical interrelations are carried out on basis of the dynamic activity of the brain hemispheres that ordered by means of such “global” interactions. Such system organization of intercortical interactions can provide both safety of individual properties of personality and the ability of the brain to effectively adapt to various influences of environment at phenotype formation in ontogenesis.

Linking the evolution of two prefrontal brain regions to social and foraging challenges in primates.

The diversity of cognitive skills across primates remains both a fascinating and a controversial issue. Recent comparative studies provided conflicting results regarding the contribution of social vs ecological constraints to the evolution of cognition. Here, we used an interdisciplinary approach combining comparative cognitive neurosciences and behavioral ecology. Using brain imaging data from 16 primate species, we measured the size of two prefrontal brain regions, the frontal pole (FP) and the dorso-lateral prefrontal cortex (DLPFC), respectively, involved in metacognition and working memory, and examined their relation to a combination of socio-ecological variables. The size of these prefrontal regions, as well as the whole brain, was best explained by three variables: body mass, daily traveled distance (an index of ecological constraints), and population density (an index of social constraints). The strong influence of ecological constraints on FP and DLPFC volumes suggests that both metacognition and working memory are critical for foraging in primates. Interestingly, FP volume was much more sensitive to social constraints than DLPFC volume, in line with laboratory studies showing an implication of FP in complex social interactions. Thus, our data highlights the relative weight of social vs ecological constraints on the evolution of specific prefrontal brain regions and their associated cognitive operations in primates.

Linking the evolution of two prefrontal brain regions to social and foraging challenges in primates

The diversity of cognitive skills across primates remains both a fascinating and a controversial issue. Recent comparative studies provided conflicting results regarding the contribution of social vs ecological constraints to the evolution of cognition. Here, we used an interdisciplinary approach combining comparative cognitive neurosciences and behavioral ecology. Using brain imaging data from 16 primate species, we measured the size of two prefrontal brain regions, the frontal pole (FP) and the dorso-lateral prefrontal cortex (DLPFC), respectively, involved in metacognition and working memory, and examined their relation to a combination of socio-ecological variables. The size of these prefrontal regions, as well as the whole brain, was best explained by three variables: body mass, daily traveled distance (an index of ecological constraints), and population density (an index of social constraints). The strong influence of ecological constraints on FP and DLPFC volumes suggests that both metacognition and working memory are critical for foraging in primates. Interestingly, FP volume was much more sensitive to social constraints than DLPFC volume, in line with laboratory studies showing an implication of FP in complex social interactions. Thus, our data highlights the relative weight of social vs ecological constraints on the evolution of specific prefrontal brain regions and their associated cognitive operations in primates.

Exploring the Mechanisms and Functions of the Impact of Ketamine on Spatial Orientation Decision Making

The aim of the study is to explore the impact of ketamine on sound perception and spatial orientation decision making, and the mechanism of how ketamine impacts perception and decision abilities. The methods used include behavioral and histology approaches. From the results, it can be concluded one of the brain regions affected by ketamine is TeA(temporal association area), which plays a vital role in sound perception and spatial orientation. An unexpected finding is that ketamine impacts left turning and right turning decisions at different degree, which requires further research on ketamine’s different impact on two cerebral hemispheres. In all, the study’s findings help people further understand how ketamine impacts spatial and sound perception.

Infantile Intraparenchymal Brain Abscess due to Streptococcus pyogenes

Introduction Group A ß-hemolytic streptococcus (GABHS) are the most common bacterial cause of tonsillitis, and can cause noninvasive diseases such as pharyngitis and impetigo, as well as more severe invasive diseases. The incidence of invasive disease is 1-3/100,000 per year, and the morbidity and mortality rate is high. GABHS is rarely lead to brain abscesses. Case Report Acute phase reactants were found to be high in a 40-day-old patient who presented with fever, irritability and focal seizures. Acute phase reactants were high. Transfontanel ultrasonography showed increased thickness, echo and blood supply in the meninges. Brain magnetic resonance imaging (MRI) and diffusion MRI revealed a thick-walled abscess in the right cerebral hemisphere and parietooccipital parenchyma with diffusion restriction on diffusion-weighted images. Cerebrospinal fluid (CSF) polymerase chain reaction (PCR) test revealed S. pyogenes,and S. pyogenes grown in CSF culture. Initially, meropenem, vancomycin, metronidazole antibiotherapy was applied. Treatment was revised to cefotaxime and vancomycin after culture antibiogram and was completed for 8 weeks. Seizures regressed. Control brain imaging showed improvement. Restriction in left lower extremity movements remained. Physical therapy and rehabilitation was recommended and he was discharged. Conclusion GABHS, which is the causative agent of acute tonsillitis, rarely causes invasive disease which has high mortality and morbidity.

The phobic brain: Morphometric features correctly classify individuals with small animal phobia.

Specific phobia represents an anxiety disorder category characterized by intense fear generated by specific stimuli. Among specific phobias, small animal phobia (SAP) denotes a particular condition that has been poorly investigated in the neuroscientific literature. Moreover, the few previous studies on this topic have mostly employed univariate analyses, with limited and unbalanced samples, leading to inconsistent results. To overcome these limitations, and to characterize the neural underpinnings of SAP, this study aims to develop a classification model of individuals with SAP based on gray matter features, by using a machine learning method known as the binary support vector machine. Moreover, the contribution of specific structural macro-networks, such as the default mode, the salience, the executive, and the affective networks, in separating phobic subjects from controls was assessed. Thirty-two subjects with SAP and 90 matched healthy controls were tested to this aim. At a whole-brain level, we found a significant predictive model including brain structures related to emotional regulation, cognitive control, and sensory integration, such as the cerebellum, the temporal pole, the frontal cortex, temporal lobes, the amygdala and the thalamus. Instead, when considering macro-networks analysis, we found the Default, the Affective, and partially the Central Executive and the Sensorimotor networks, to significantly outperform the other networks in classifying SAP individuals. In conclusion, this study expands knowledge about the neural basis of SAP, proposing new research directions and potential diagnostic strategies.

A patient with heterochronous double primary tumor of basal ganglia germ cell tumors followed by diffuse hemispheric glioma: a case report.

Basal ganglia germ cell tumor (BGGCT) is a rare central nervous system (CNS) tumor. Diffuse hemispheric gliomas, H3 G34-mutant (DHGs) is an invasive glioma involving the cerebral hemispheres. The diagnosis of DHGs depends on the integration of histopathology and molecular pathology. We reported a patient with an initial diagnosis of BGGCT that was sensitive to subsequent chemoradiotherapy. Unfortunately, a second high-grade glioma was found on magnetic resonance imaging (MRI) six years later. Subsequently, the tumor was completely removed after surgery and the following histopathology plus next generation sequencing (NGS) testing confirmed the diagnosis of DHGs. Interestingly, we found a germline likely pathogenic variant in FANCA. After surgery, the patient received Stupp regimen. The patient had a relapse 13months after the Stupp regimen and was doing well after surgery. This is the first report of a patient with heterochronous double primary tumor of BGGCT followed by DHGs.

Life-Threatening Spontaneous Hematoma in Unusual Sites in Patients with COVID-19 on Anticoagulant Therapy: A Case Series

Thromboembolic manifestations are a common phenomenon in patients affected by corona virus (SARS CoV-2). Recent studies have shown that patients with acute renal failure are also at a greater risk of venous and arterial thromboembolism, 15-30% in ICU, and 7% inpatient care. However, frequently unjudicial use of anticoagulants may develop severe life-threatening hematoma. In our hospital settings we had a dedicated COVID Unit with a Hemodialysis facility. Our Nephrology department had managed 381 patients being COVID positive along with renal impairment from March 2020 to January 2022. Among these patients, four patients developed spontaneous non traumatic hematoma in unusual sites. On admission all the patients received treatment according to our national guidelines for COVID-19. Cases: It is a retrospective analysis in a single-centered hospital. Four cases with confirmed COVID-19 with acute kidney injury and on anticoagulant therapy had developed sudden concealed bleeding. These patients had no previous history of anticoagulant therapy before admission. Case 1 developed hemorrhage in Right lower anterior paramedian deep parietal wall of abdomen, Case 2 had hematoma in retroperitoneal space and in lower third of Iliopsoas, Case 3 developed hemorrhage in left cerebral hemisphere, Case 4 had Intramuscular Hematoma in left rectus abdominis. Out of these four patients two of them required Hemodialysis and one of them went into shock. All patients included were male. The mean age was 57±19.64years. All the four patients were initially managed conservatively with keen monitoring and with proper volume resuscitation, blood transfusion and discontinuation of the anticoagulants. Three of the patients survived with conservative management and one patient died due to sudden massive cardiac arrest. The use of therapeutic anticoagulant can increase the risk of bleeding in atypical sites and may exhibit higher patient death with COVID-19 if not identified at early stage. So a risk-benefit ratio of usage of anticoagulants should be kept in mind and further clinical trials needed to justify its random use in COVID-19. J Bangladesh Coll Phys Surg 2024; 42: 393-400

Correlation of degree and pattern of contrast enhancement on Magnetic Resonance Imaging with histopathological grade of intracranial astrocytoma

Background/Objective: Astrocytomas, a type of glioma, require accurate grading to guide treatment. This study evaluates the correlation between MRI contrast enhancement and histopathological grades of astrocytomas. Methods: A cross-sectional study of 37 patients with biopsy-confirmed astrocytomas was conducted. Non-probability or purposive sampling was carried out. MRI scans assessed contrast enhancement characteristics, and tumors were classified radiologically and histopathologically. Results: The age range of the patients was 11 to 74 years and mean age was 40.25±16.04 years. The male to female ratio was 4:1. Headache was the most common presenting symptoms (95%). Most of the tumors were located at the cerebral hemispheres (78%). None or slight contrast enhancement was found in 17 (46%) and the pattern of contrast enhancement was heterogeneous in 24 (65%) patients. Maximum 20 (54%) patients had high grade astrocytoma. In the present study, 85% high grade astrocytoma showed moderate to marked whereas 82.4% low grade astrocytoma showed none or slight contrast enhancement. Sensitivity & specificity of contrast enhanced MRI was 82.4% and 85% respectively. The overall accuracy was 83.78%. Conclusion: MRI is a reliable non-invasive tool for grading astrocytomas, with strong correlation between contrast enhancement and tumor grade, supporting its use in clinical decision-making. J Shaheed Suhrawardy Med Coll 2023; 15(1): 13-19

Radiological, clinical, and molecular analyses reveal distinct subtypes of butterfly glioblastomas affecting the prognosis

Abstract Background Glioblastoma (GB) is known for its highly invasive nature. Images of butterfly GB (bGB) often illustrate this characteristic, but the molecular background and origins of bGB remain unknown. Methods We analyzed a cohort of 34 bGB patients from our dataset (K-cohort) and 46 bGB patients from publicly available datasets, including TCGA-GBM, CPTAC-GBM, IvyGAP, and UPENN-GBM. Results In the K-cohort, the median age was 66 years, and molecular analyses revealed TERT promoter mutations in 55.9% of cases, with no cases exhibiting H3F3A, HIST1H3B, or BRAF mutations. Sequential radiological imaging from the K-cohort provided unique insights, showing one case originating in the corpus callosum (CC) and three cases originating in the cerebral hemisphere before developing into bGB. Multi-regional sampling supported a mutational trajectory from the hemisphere to the CC. These observations indicate the presence of two distinct radiological origins for bGB. Consequently, we classified cases into CC-type and Hemispheric-type based on the tumor volume ratio within the CC. This subgrouping was clinically meaningful; the CC-type is an independent poor prognostic factor for overall survival, with a hazard ratio of 1.8 (95% confidence interval 1.1-3.0, P = 0.033), and is molecularly distinct by a higher frequency of methylated MGMTp (P = 0.0039) compared to the Hemispheric-type. Conclusions Our results highlight that the radiological features of bGB are not homogenous and can indicate two potential subtypes based on their origins. Further studies are mandatory, but CC-type and Hemispheric-type exhibit distinct clinical backgrounds, outcomes, and molecular features.

Pain resilience dimensions and regional gray matter volume as risk factors for poor outcomes of chronic pain: a prospective cohort study.

Pain resilience and regional gray matter volume (rGMV) are established correlates of adaptation to chronic pain within cross-sectional studies. Extending such work, this prospective cohort study tested the status of baseline pain resilience dimension scores and rGMV as risk factors for subsequent exacerbations in chronic pain disability and intensity. 142 adults with chronic musculoskeletal pain completed an initial assessment comprising a structural magnetic resonance imaging scan and self-report measures of cognitive/affective positivity and behavioral perseverance pain resilience dimensions, disability, pain intensity, and demographics. Disability and pain intensity were outcomes re-assessed at a 6-month follow-up. The impact of pain resilience dimension scores and identified rGMV sites on follow-up outcomes was examined after controlling for other baseline correlates of outcomes. Mediating effects of identified rGMV sites on pain resilience dimension-follow-up outcome relations were also evaluated. Aside from the significant multivariate effect of lower behavioral perseverance and cognitive/affective positivity scores, augmented left precuneus, temporal pole, superior temporal gyrus (STG), and precentral gyrus rGMV combined to predict higher follow-up disability levels, independent of covariates. Higher left fusiform gyrus rGMV levels predicted follow-up exacerbations in pain intensity, but pain resilience dimension scores did not. Finally, left precuneus and left temporal pole STG rGMV partially mediated cognitive/affective positivity-follow-up disability relations. Findings underscore deficits in pain resilience and increased rGMV as potential risk factors for poorer subsequent outcomes of chronic musculoskeletal pain and provide foundations for further prospective extensions as well as targeted intervention research.

Electroencephalographic monitoring in detection and prediction of delayed cerebral ischemia due to non-traumatic subarachnoid hemorrhage

Intensive care of patients with acute non-traumatic subarachnoid hemorrhage primarily relies on diagnostics of delayed cerebral ischemia (DCI). The major difficulty in detecting DCI emerges upon suppression of wakefulness, when clinical assessment of growing neurological deficit becomes complicated. Widely used transcranial dopplerography allows solely to verify a vasospasm development not always leading to DCI exhibiting a multifactorial underlying mechanism. Electroencephalography (EEG) is the only broadly available instrumental tool ensuring a continuous monitoring of cerebral functional status including in subjects at intensive care unit. To date, non-specific EEG parameters pointing at development of acute cerebral injury were identified that provide varying diagnostic and predictive informative value in DCI. We reviewed publications aimed at assessing the data on visual and quantitative EEG parameters such as regional slowing, alpha rhythm spectral power and relative variability, alpha-to-delta power ratio, and detection of epileptiform activity. Having searched international and Russia-wide medical databases, we found only 7 publications quantitatively assessing diagnostic value of EEG monitoring, which showed that for DCI diagnosis its sensitivity ranged from 76% to 100%, and specificity – from 54% to 100%. We also present a clinical case with a 70-year-old female patient who underwent surgery for non-traumatic subarachnoid hemorrhage due to a ruptured aneurysm of the communicating segment of the right internal carotid artery. During the continuous videoEEG monitoring 2 days before clinical deterioration and appearance of ischemic changes in the right cerebral hemisphere on computed tomography scans, an ictal-interictal continuum pattern was noted to emerge. Future studies should be aimed at clarifying and validating the most informative DCI biomarkers including while recording EEG with intracranial electrodes that may contribute to development of automated algorithms for DCI detection.

Intracranial EEG-Based Directed Functional Connectivity in Alpha to Gamma Frequency Range Reflects Local Circuits of the Human Mesiotemporal Network.

To date, it is largely unknown how frequency range of neural oscillations measured with EEG is related to functional connectivity. To address this question, we investigated frequency-dependent directed functional connectivity among the structures of mesial and anterior temporal network including amygdala, hippocampus, temporal pole and parahippocampal gyrus in the living human brain. Intracranial EEG recording was obtained from 19 consecutive epilepsy patients with normal anterior mesial temporal MR imaging undergoing intracranial presurgical epilepsy diagnostics with multiple depth electrodes. We assessed intratemporal bidirectional functional connectivity using several causality measures such as Granger causality (GC), directed transfer function (DTF) and partial directed coherence (PDC) in a frequency-specific way. In order to verify the obtained results, we compared the spontaneous functional networks with intratemporal effective connectivity evaluated by means of SPES (single pulse electrical stimulation) method. The overlap with the evoked network was found for the functional connectivity assessed by the GC method, most prominent in the higher frequency bands (alpha, beta and low gamma), yet vanishing in the lower frequencies. Functional connectivity assessed by means of DTF and PCD obtained a similar directionality pattern with the exception of connectivity between hippocampus and parahippocampal gyrus which showed opposite directionality of predominant information flow. Whereas previous connectivity studies reported significant divergence between spontaneous and evoked networks, our data show the role of frequency bands for the consistency of functional and evoked intratemporal directed connectivity. This has implications for the suitability of functional connectivity methods in characterizing local brain circuits.

Technical Feasibility of Delineating the Thalamic Gustatory Tract Using Tractography.

Magnetic resonance-guided focused ultrasound (MRgFUS) has been increasingly performed in recent years as a minimally invasive treatment of essential tremor and tremor-dominant Parkinson disease. One of the side effects after treatment is dysgeusia. Some centers use tractography to facilitate the treatment planning. However, there have been no reports of identifying gustatory tracts so far. Our aim was to investigate the technical feasibility of isolating and visualizing the gustatory tracts, as well as to explore the relationship between the gustatory tract and the MRgFUS lesion using actual patient data. We used 20 randomly selected individuals from the Human Connectome Project database to perform tractography of the gustatory tracts. We defined region of interest as the dorsal region of the brainstem, Brodmann area 43 associated with taste perception, and a sphere with a 3-mm radius centered around the ventral intermediate nucleus in the anterior commissure-posterior commissure plane. We also examined the position of the gustatory tract in relation with other tracts, including the medial lemniscus, the pyramidal tract, and the dentatorubrothalamic tract. In addition, using the data of real patients with essential tremor, we investigated the distance between MRgFUS lesions and the gustatory tract and its association with the development of dysgeusia. We delineated a mean of 15 streamlines of the gustatory tracts per subject in each hemisphere. There was no statistical difference in the localization of the gustatory tracts between the left and right cerebral hemispheres. The gustatory tract was located anteromedial to the medial lemniscus and posteromedial to the dentatorubrothalamic tract in the anterior commissure-posterior commissure plane. The distance from the MRgFUS lesion to the gustatory tract was significantly shorter in the case where dysgeusia occurred compared with nondysgeusia cases (P-value: .0068). The thalamic gustatory tracts can be reliably visualized using tractography.

Profiles of brain topology for dual-functional stability in old age.

Dual-functional stability (DFS) in cognitive and physical abilities is important for successful aging. This study examines the brain topology profiles that underpin high DFS in older adults by testing two hypotheses: (1) older adults with high DFS would exhibit a unique brain organization that preserves their physical and cognitive functions across various tasks, and (2) any individuals with this distinct brain topology would consistently show high DFS. We analyzed two cohorts of cognitively and physically healthy older adults from the UK (Cam-CAN, n = 79) and the US (CF, n = 48) using neuroimaging data and a combination of cognitive and physical tasks. Variability in DFS was characterized using k-mean clustering for intra-individual variability (IIV) in cognitive and physical tasks. Graph theory analyses of diffusion tensor imaging connectomes were used to assess brain network segregation and integration through clustering coefficients (CCs) and shortest path lengths (PLs). Using support vector machine and regression, brain topology features, derived from PLs + CCs, differentiated the high DFS subgroup from low and mix DFS subgroups with accuracies of 65.82% and 84.78% in Cam-CAN and CF samples, respectively, which predicted cross-task DFS score in CF samples at 58.06% and 70.53% for cognitive and physical stability, respectively. Results showed distinctive neural correlates associated with high DFS, notably varying regional brain segregation and integration within critical areas such as the insula, frontal pole, and temporal pole. The identified brain topology profiles suggest a distinctive neural basis for DFS, a trait indicative of successful aging. These insights offer a foundation for future research to explore targeted interventions that could enhance cognitive and physical resilience in older adults, promoting a healthier and more functional lifespan.

The impact of Brain-Based Learning on critical and creative thinking in English Language Teaching

This paper investigates the impact of Brain-Based Learning (BBL) strategies on fostering critical and creative thinking skills in English language teaching. In the context of 21st-century education, where the demands for innovation, critical thinking, and problem-solving are paramount, BBL emerges as a pedagogical approach that aligns teaching methods with cognitive science principles. Through a qualitative exploration of teacher perspectives and a quantitative analysis of classroom outcomes, this study highlights how BBL encourages the development of both hemispheres of the brain, promoting not only logical reasoning but also imaginative problem-solving. The findings underscore the potential of BBL to transform traditional English language teaching (ELT) practices by fostering a more holistic, engaging, and dynamic learning environment. Practical recommendations for integrating BBL into English classrooms are also provided..