Background: Accurate diagnosis of cerebral ischemia severity is crucial for clinical decision making. Laser speckle contrast imaging-based cerebral blood flow imaging can help assess the severity of cerebral ischemia by monitoring changes in blood flow. Method: In this study, we simulated hyperacute ischemia in rats, isolating arterial and venous flow-related signals from cortical vasculature. Pearson correlation was used to examine the correlation between damaged vessels. Granger causality analysis was used to investigate causality correlation in ischemic vessels. Results: Resting state analysis revealed a negative Pearson correlation between regional arteries and veins. Following cerebral ischemia induction, a positive artery-vein correlation emerged, which vanished after blood flow reperfusion. Granger causality analysis demonstrating enhanced causality coefficients for middle artery-vein pairs during occlusion, with a stronger left-right arterial effect than that of right-left, which persisted after reperfusion. Conclusions: These processing approaches amplify the understanding of cerebral ischemic images, promising potential future diagnostic advancements.

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Background: The basal ganglia-thalamocortical (BGTC) and cerebello-thalamocortical (CTC) networks are implicated in tremor genesis; however, exact contributions across disorders have not been studied. Objective: Evaluate the structural connectivity of BGTC and CTC in tremor-dominant Parkinson's disease (TDPD) and essential tremor plus (ETP) with the aid of probabilistic tractography and graph theory analysis. Methods: Structural connectomes of the BGTC and CTC were generated by probabilistic tractography for TDPD (n = 25), ETP (ET with rest tremor, n = 25), and healthy control (HC, n = 22). The Brain Connectivity Toolbox was used for computing standard topological graph measures of segregation, integration, and centrality. Tremor severity was ascertained using the Fahn-Tolosa-Marin tremor rating scale (FTMRS). Results: There was no difference in total FTMRS scores. Compared with HC, TDPD had a lower global efficiency and characteristic path length. Abnormality in segregation, integration, and centrality of bilateral putamen, globus pallidus externa (GPe), and GP interna (GPi), with reduction of centrality of right caudate and cerebellar lobule 8, was observed. ETP showed reduction in segregation and integration of right GPe and GPi, ventrolateral posterior nucleus, and centrality of right putamen, compared with HC. Differences between TDPD and ETP were a reduction of strength of the right putamen, and lower clustering coefficient, local efficiency, and strength of the left GPi in TDPD. Conclusions: Contrary to expectations, TDPD and ETP may not be significantly different with regard to tremor pathogenesis, with definite overlaps. There may be fundamental similarities in network disruption across different tremor disorders with the same tremor activation patterns, along with disease-specific changes.

Introduction: This study aims to use diffusion tensor imaging (DTI) in conjunction with brain graph techniques to define brain structural connectivity and investigate its association with personal income (PI) in individuals of various ages and intelligence quotients (IQ). Methods: MRI examinations were performed on 55 male subjects (mean age: 40.1 ± 9.4 years). Graph data and metrics were generated, and DTI images were analyzed using tract-based spatial statistics (TBSS). All subjects underwent the Wechsler Adult Intelligence Scale for a reliable estimation of the full-scale IQ (FSIQ), which includes verbal comprehension index, perceptual reasoning index, working memory index, and processing speed index. The performance score was defined as the monthly PI normalized by the age of the subject. Results: The analysis of global graph metrics showed that modularity correlated positively with performance score (p = 0.003) and negatively with FSIQ (p = 0.04) and processing speed index (p = 0.005). No significant correlations were found between IQ indices and performance scores. Regional analysis of graph metrics showed modularity differences between right and left networks in sub-cortical (p = 0.001) and frontal (p = 0.044) networks. TBSS analysis showed greater axial and mean diffusivities in the high-performance group in correlation with their modular brain organization. Conclusion: This study showed that PI performance is strongly correlated with a modular organization of brain structural connectivity, which implies short and rapid networks, providing automatic and unconscious brain processing. Additionally, the lack of correlation between performance and IQ suggests a reduced role of academic reasoning skills in performance to the advantage of high uncertainty decision-making networks.

Introduction: The subventricular zone promotes remyelination through activation differentiation of oligodendroglial precursor cells (OPCs) and neural stem cells (NSCs) into mature oligodendrocytes and thus in the adult brain. In multiple sclerosis (MS) this regenerative capability is halted resulting in neurodegeneration. We aimed to systematically search and synthesize evidence on mechanisms and phenomena associated with subventricular zone (SVZ) dysfunction in MS. Materials and Methods: Our systematic review was reported according to the PRISMA-ScR statement. MEDLINE, SCOPUS, ProQuest, and Google Scholar were searched using the terms "subventricular zone" and "multiple sclerosis," including English-written invivo and postmortem studies. Results: Twenty studies were included. Thirteen studies on models of experimental autoimmune encephalomyelitis (EAE) reported among others strong stathmin immunoreactivity in the SVZ of EAE models, the role of MOG immunization in neurogenesis impairment, the effect of parenchymal OPCs and NSCs in myelin repair, and the importance of ependymal cells (E1/E2) and ciliated B1 cells in SVZ stem cell signaling. CXCR4 signaling and transcriptional profiles of SVZ microglia, Gli1 pathway, and galactin-3 were also explored. Studies in humans demonstrated microstructural SVZ damage in progressive MS and the persistence of black holes near the SVZ, whereas postmortem confirmed the generation of polysialic acid-neural cell adhesion molecule and NG2-positive progenitors through SVZ activation, SVZ stathmin immunoreactivity, Shh pathway, and Gal-3 upregulation. Discussion: Oligodendrogenesis defects translate to reduced remyelination, a hallmark of MS that determines its end-phenotype and disease course. Conclusion: The role of inflammation and subsequent SVZ microenvironment disruption is evident in MS pathology.

Introduction: The mental load caused by simultaneous multitasking can affect visual information processing and reduce its ability. This study investigated the effect of mental load caused by cognitive tasks simultaneously with visual task on the number of active voxels in the visual cortex. Methods: This study recruited 22 individuals with a mean age of 24.72 ± 5.47 years. 3-Tesla functional magnetic resonance imaging (fMRI) was used to examine the functions of the visual cortex and amygdala region during three different task conditions: visual task alone, visual task with an auditory n-back task, and visual task with an arithmetic task. The visual stimuli consisted of Gabor patches with a contrast of 55% at spatial frequencies of 0.25, 4, and 9 cycles per degree (cpd). These were presented in three trials of eight blocks with a stimulation time of 12 sec and a rest time of 14 sec. Results: Activated brain voxels in the primary, secondary, and associated visual cortex areas were reduced in response to the mental load imposed by the n-back and arithmetic tasks. This reduction was greater for a spatial frequency of 0.25 cpd in the n-back task condition and spatial frequency of 9 cpd in the arithmetic task condition. In addition, the amygdala was stimulated in 2-back task and arithmetic task conditions. Conclusions: This study revealed a decline in the number of activated voxels of the visual cortex due to the mental load caused by simultaneous cognitive tasks, confirming the findings of previous psychophysical studies.

Narrative comprehension is a linguistic ability that emerges early in life and has a critical role in language development, reading acquisition, and comprehension. According to the Simple View of Reading model, reading is acquired through word decoding and linguistic comprehension. Here, within and between networks, functional connectivity in several brain networks supporting both language and reading abilities was examined from prereading to proficient reading age in 32 healthy children, ages 5-18 years, scanned annually while listening to stories over 12 years. Functional connectivity changes within and between the networks were assessed and compared between the years using hierarchical linear regression and were related to reading abilities. At prereading age, the networks related to basic language processing accounted for 32.5% of the variation of reading ability at reading age (at 12-14 years) (R2 = 0.325, p = 0.05). At age 17, more complex cognitive networks were involved and accounted for 97.4% of the variation in reading ability (R2 = 0.974, p = 0.022). Overall, networks composing the future-reading network are highly involved in processing narratives along development; however, networks related to semantic, phonological, and syntactic processing predict reading ability earlier in life, and more complex networks predict reading proficiency later in life.

Traumatic brain injury (TBI) and stroke are the most common causes of acquired brain injury (ABI), annually affecting 69 million and 15 million people, respectively. Following ABI, the relationship between brain network disruption and common cognitive issues including attention dysfunction is heterogenous. Using PRISMA guidelines, we systematically reviewed 43 studies published by February 2023 that reported correlations between attention and connectivity. Across all ages and stages of recovery, following TBI, greater attention was associated with greater structural efficiency within/between executive control network (ECN), salience network (SN), and default mode network (DMN) and greater functional connectivity (fc) within/between ECN and DMN, indicating DMN interference. Following stroke, greater attention was associated with greater structural connectivity (sc) within ECN; or greater fc within the dorsal attention network (DAN). In childhood ABI populations, decreases in structural network segregation were associated with greater attention. Longitudinal recovery from TBI was associated with normalization of DMN activity, and in stroke, normalization of DMN and DAN activity. Results improve clinical understanding of attention-related connectivity changes after ABI. Recommendations for future research include increased use of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) to measure connectivity at the point of care, standardized attention and connectivity outcome measures and analysis pipelines, detailed reporting of patient symptomatology, and casual analysis of attention-related connectivity using brain stimulation.

Introduction: The purpose of this study was to monitor and record the dynamic brain activity of patients with moyamoya disease (MMD), as well as to study the relationship between brain abnormalities and presenting clinical features. Methods: A total of 16 patients with MMD (2 males and 14 females) were invited to participate in the study, as were healthy controls (HCs) with the same number and sex ratio. In this study, the dynamic amplitude of low-frequency fluctuation (dALFF) was utilized to assess changes in spontaneous brain activity. Moreover, we also used correlation analysis to study the relationship among the measured mean of dALFF, behavioral performances, and the retinal nerve fiber layer and the Hospital Anxiety and Depression Scale (HADS) score to explore the potential relationship between MMD and anxiety and depression. Results: Our study reveals that in MMD, dALFF levels decreased in the left lingual gyrus, right insula, and occipital lobe. Discussion: In this study, we found and discussed the potential relationship between the abnormal activities in multiple brain regions and related functional network disorders in patients with MMD, as well as the damage to brain regions that process emotion and vision, in the hopes of providing more ideas for the clinical diagnosis and treatment of MMD.