Brain Areas Research Articles

Phonemic word fluency is related to temporal and striatal gray matter volume in healthy older adults

ABSTRACT Word fluency (WF) tasks that tap verbal and executive function show deteriorating performance by advancing age. To address the scarcely studied age-related brain correlates of WF, we employed whole-brain voxel-based morphometry to examine gray matter (GM) correlates of semantic and phonemic WF in 46 healthy older adults. Lower phonemic WF score was related to smaller anterior medial temporal GM volume as well as smaller GM volume in the putamen bilaterally. A disproportionally weak score on phonemic WF in relation to semantic WF was associated with smaller GM volume in the left inferior frontal cortex, the right anterior medial temporal lobe, and the right striatum. There were no significant associations for semantic WF. The fact that our temporal and subcortical findings were bilateral and right-lateralized, may reflect age-related compensation by these brain areas.

Gender and Age Differences in Corpus Callosum Morphology: High-Altitude Adaptations in Native Tibetan Populations.

The corpus callosum is recognized as the largest interhemispheric white matter structure, coordinating distinct functions of the brain. High-altitude environments may influence the structure of the corpus callosum. This study aims to evaluate the morphologic characteristics of the corpus callosum in Tibetans residing on the Qinghai-Tibet Plateau while investigating the effects of sex, age, and high-altitude exposure on its morphology. The study comprised 262 healthy native Tibetan adults, including 113 men and 149 women. The length, height, area, and thickness of each subregion of the corpus callosum were measured, with the data normalized according to brain length and mid-sagittal cortical brain area. Statistical analyses were conducted utilizing nonparametric tests and partial correlation analysis. Most normalized morphologic measurements indicated significant sex differences, particularly in the thickness of the rostrum (z=-3.199, P=0.001), genu (z=-3.133, P=0.002), body (z=-3.612, P<0.001), splenium (z=-2.279, P=0.02), and callosal length (z=-2.722, P=0.006), and area (z=-2.179, P=0.03). The callosal area (R2=0.084, P<0.001) demonstrated an inverted U-shaped trajectory throughout the lifespan, peaking at ∼40 years of age. This study identified pronounced sex differences in the corpus callosum morphology among Tibetans. Despite living at high altitudes, the age-related trajectory of the callosal area resembled patterns observed in other populations, although peak ages differed by sex.

The Neural Basis of Event Segmentation: Stable Features in the Environment are Reflected by Neural States

Abstract Our senses receive a continuous stream of complex information. Parsing this information into meaningful events allows us to extract relevant information, remember it, and act upon it. Previous research has related these events to so-called ‘neural states’: temporally and regionally specific stable patterns of brain activity, which tend to coincide with events in the stimulus. Neural states show a temporal cortical hierarchy: short states are present in early sensory areas, while longer states can be found in higher-level areas. Here we investigated what these neural states represent. We hypothesized that states at different levels of the cortical hierarchy are shaped by aspects of the stimulus to which these brain areas are responsive. To test this hypothesis, we analyzed fMRI data of participants watching a movie, using a data-driven method to identify the neural states. We found support for the aforementioned hypothesis: specifically the parahippocampal place area and retrosplenial cortex, known to be sensitive to places, showed an alignment between neural state boundaries and moments in the movie with a change in location, independent of changes in visual features and other covariates. These findings suggest that neural states reflect stable features in the (internal model of) the external environment, and that the cortical temporal hierarchy partly reflects the temporal scales at which representations of the environment evolve.

Establishment and evaluation of a carotid artery dissection model in rats

BackgroundGiven the lack of models for carotid artery dissections (CAD), we aim to investigate effects of beta-aminopropionitrile (BAPN) combined with physical damage on the arterial walls of rats, and to establish a high-incidence and low-mortality CAD model.MethodsSixteen SPF SD rats (3-week-old) were divided into two groups. Group B was given 0.25% BAPN solution and group W was given water. Then we established an animal model of CAD by carotid artery torsion. One of the two carotid arteries in each rat was randomly selected for torsion. We got four groups of blood vessels following above-mentioned methods: BAPN plus torsion group (group Bt), BAPN plus non-torsion group (group Bn), water plus torsion group (group Wt), and water plus non-torsion group (group Wn). The hematoxylin and eosin (HE) staining and Verhoeff’s Van Gieson (EVG) staining were performed to observe structures of arteries. Immunofluorescence staining was used to detect structural proteins in vessels. We used triphenyltetrazolium chloride (TTC) staining and neurological function assessment to detect the infarct area of brain and neurological deficits in rats with carotid dissection to verify the validity of the rat model.ResultsBAPN treatment significantly affected the weight gain of rats, but had little effect on survival during the first 5 weeks. The group Bt had the highest incidence of CAD among all groups (p = 0.014). HE staining of carotid artery tissue sections showed that the vascular walls were the thickest in group Bt (p &amp;lt; 0.001). EVG staining showed the arrangement of elastic fibers was the most irregular in group Bt. Immunofluorescence staining revealed that the expression of a-SMA and SM22a were decreased remarkably in group Bt (p &amp;lt; 0.001). Both motor and sensory deficits were more severe in CAD group than control group (p = 0.0004; p = 0.0036). The relative infarction volumes of CAD group rats were significantly larger than control group (p &amp;lt; 0.001).ConclusionThe animal model of CAD can be feasible to establish by mechanical torsion combined with BAPN free drinking. With this method, the animal mortality was low and the model formation rate was high. This model will enable further studies on CAD.

Apocynin, a Selective NADPH Oxidase (Nox2) Inhibitor, Ameliorates Behavioural and Learning Deficits in the Fragile X Syndrome Mouse Model

Background/Objectives: Fragile X Syndrome (FXS) is associated with intellectual disability, hyperactivity, social anxiety and signs of autism. Hyperactivation of NADPH oxidase has been previously described in the brain of the male Fmr1-KO mouse. This work aims to demonstrate the efficacy of Apocynin, a specific NADPH oxidase inhibitor, in treating Fragile X mouse hallmarks. Methods: Free radicals, lipid and protein oxidation markers and behavioural and learning paradigms were measured after chronic treatment with orally administered vehicle, 10 mg/kg/day or 30 mg/kg/day of Apocynin. Results: The results revealed a reduction in testis weight, an increase in peritoneal fat, and no variation in body weight after chronic treatment. Furthermore, a reduction in hyperactivity was detected in Apocynin-treated male Fmr1-KO mice. Additionally, the higher dose of 30 mg/kg/day also improves behaviour and learning in the male Fmr1-KO mice, normalising free radical production and oxidative parameters. Moreover, a reduction in phospho-EKR1 and P47-Phox protein signals was observed in specific brain areas. Conclusions: Thus, chronic treatment with Apocynin could lead to a new therapeutic option for the Fragile X Syndrome.

Exploring neural mechanisms of gender differences in bodily emotion recognition: a time-frequency analysis and network analysis study

BackgroundThis study aimed to explore the neural mechanisms underlying gender differences in recognizing emotional expressions conveyed through body language. Utilizing electroencephalogram (EEG) recordings, we examined the impact of gender on neural responses through time-frequency analysis and network analysis to uncover gender disparities in bodily emotion recognition.MethodsThe study included 34 participants, consisting of 18 males and 16 females. A 2 × 2 mixed design was employed, with gender (male and female) and bodily emotion (happy and sad) as the independent variables. Both behavioral and EEG data were collected simultaneously.ResultsMales demonstrated more stable brain activity patterns when recognizing different bodily emotions, while females showed more intricate and highly interconnected brain activity networks, especially when identifying negative emotions like sadness. Differences based on gender were also observed in the significance of brain regions; males had greater importance in central brain areas, whereas females exhibited higher significance in the parietal lobe.ConclusionGender differences do influence the recognition of bodily emotions to some extent. The primary aim of this study was to explore the neural mechanisms underlying gender differences in bodily emotion recognition, with a particular focus on time-frequency analysis and network analysis based on electroencephalogram (EEG) recordings. By elucidating the role of gender in cognitive development, this study contributes to early detection and intervention.

Microstructural asymmetries of the planum temporale predict functional lateralization of auditory-language processing.

Structural hemispheric asymmetry has long been assumed to guide functional lateralization of the human brain, but empirical evidence for this compelling hypothesis remains scarce. Recently, it has been suggested that microstructural asymmetries may be more relevant to functional lateralization than macrostructural asymmetries. To investigate the link between microstructure and function, we analyzed multimodal MRI data in 907 right-handed participants. We quantified structural asymmetry and functional lateralization of the planum temporale (PT), a cortical area crucial for auditory-language processing. We found associations between PT functional lateralization and several structural asymmetries, such as surface area, intracortical myelin content, neurite density, and neurite orientation dispersion. The PT structure also showed hemispheric-specific coupling with its functional activity. All these functional-structural associations are highly specific to within-PT functional activity during auditory-language processing. These results suggest that structural asymmetry underlies functional lateralization of the same brain area and highlights a critical role of microstructural PT asymmetries in auditory-language processing.

Orexin in depression: Evidence from basic and clinical research

Orexin &amp;ndash; a neuropeptide &amp;ndash; is extensively distributed in the central nervous system and is involved in the regulation of diverse physiological functions and behaviors. Orexin is strongly associated with the onset and development of depression. The most important function of orexin is to interact with the transport system, mediating arousal, and energy homeostasis. Hypothalamic-ventral tegmental and hypothalamic-ventral thalamic pathways provide clues for understanding the function of orexin and related disorders, such as sleep disorders, eating disorders, and substance abuse. This article summarizes the basic and clinical studies on the role of the orexin system in regulating and treating depression, including the relationship between the expression level of orexin in specific brain areas and diseases, relationship between adolescent depression and orexin, orexin receptor antagonists as a treatment for depression, and narcolepsy, which is closely associated with depression. Research progress on the role of orexin in depression and recent relevant studies are summarized, providing novel directions for developing depression treatment strategies.

Action observation reveals a network with divergent temporal and parietal cortex engagement in dogs compared with humans

Abstract Action observation is a fundamental pillar of social cognition. Neuroimaging research has revealed a human and non-human primate action observation network (AON) encompassing frontotemporoparietal areas with links to the species’ imitation tendencies and relative lobe expansion. Dogs (Canis familiaris) have good action perception and imitation skills and a less expanded parietal than temporal cortex, but their AON remains unexplored. We conducted a functional MRI study with 28 dogs and 40 humans and found functionally analogous involvement of somatosensory and temporal brain areas of both species’ AONs and responses to transitive and intransitive action observation in line with their imitative skills. Employing a functional localizer, we also identified functionally analogous agent-responsive areas within both species’ AONs. However, activation and task-based functional connectivity measures suggested significantly less parietal cortex involvement in dogs than in humans. These findings advance our understanding of the neural bases of action understanding and the convergent evolution of social cognition, with analogies and differences resulting from similar social environments and divergent brain expansion, respectively.

From silence to song: Testosterone triggers extensive transcriptional changes in the female canary HVC.

Seasonal song production in canaries is influenced by gonadal hormones, but the molecular mechanisms underlying testosterone-induced song development in adult female canaries, which rarely sing naturally, remain poorly understood. We explored testosterone-induced song development in adult female canaries by comparing gene regulatory networks in the song-controlling brain area HVC at multiple time points (1 h to 14 days) post-treatment with those of placebo-treated controls. Females began vocalizing within 4 days of testosterone treatment, with song complexity and HVC volume increasing progressively over 2 weeks. Rapid transcriptional changes involving 2739 genes preceded song initiation. Over 2 weeks, 9913 genes-approximately 64% of the canary's protein-coding genome-were differentially expressed, with 98% being transiently regulated. These genes are linked to various biological functions, with early changes at the cellular level and later changes affecting the nervous system level after prolonged hormone exposure. Our findings suggest that testosterone-induced song development is accompanied by extensive and dynamic transcriptional changes in the HVC, implicating widespread neuronal involvement. These changes underpin the gradual emergence of singing behavior, providing insights into the neural basis of seasonal behavioral patterns.

Ictal onset zone localization by using ECOG signals

The diagnosis of seizure onset zone is crucial in epilepsy surgery for patients having pharmacoresistant, that the localization of ictal onset zone (IOZ) is associated with epileptiform activity region, by using intracranial strip and grid electrodes of electrocorticography (ECOG). Thus, these ECOG signals determine areas of the brain which can be surgically removed by visual inspection, especially in partial epilepsy named focal seizure. However, this paper investigates recent automatic IOZ localization, based on recurrent neural network (RNN) to improve the performance of identification of IOZ. Therefore, statistical patterns in time-frequency domains are extracted after applying hybrid empirical mode decomposition (EMD) and variational mode decomposition (VMD) methods. In addition, the evaluation of this work is performed by implementation of several indicators to distinct between focal and non focal ECOG signals. Moreover, the experiment results using Bern– Barcelona dataset indicated the effectiveness of using hybrid EMD-VMD method and RNN, that the proposed model achieve better classification performance reached 100% of accuracy. Hence, by comparison with other studies in the literature review, ECoG recordings provide best localization of IOZ by using this system. Finally, this developed method shows accurate results to help clinical experts in seizure resection, and indicates localization of IOZ which can be removed from brain area.

Enhanced control of a brain-computer interface by tetraplegic participants via neural-network-mediated feature extraction.

To infer intent, brain-computer interfaces must extract features that accurately estimate neural activity. However, the degradation of signal quality over time hinders the use of feature-engineering techniques to recover functional information. By using neural data recorded from electrode arrays implanted in the cortices of three human participants, here we show that a convolutional neural network can be used to map electrical signals to neural features by jointly optimizing feature extraction and decoding under the constraint that all the electrodes must use the same neural-network parameters. In all three participants, the neural network led to offline and online performance improvements in a cursor-control task across all metrics, outperforming the rate of threshold crossings and wavelet decomposition of the broadband neural data (among other feature-extraction techniques). We also show that the trained neural network can be used without modification for new datasets, brain areas and participants.

Vigabatrin-associated brain magnetic resonance imaging abnormalities and clinical symptoms in infants with tuberous sclerosis complex.

Previous retrospective studies have reported vigabatrin-associated brain abnormalities on magnetic resonance imaging (VABAM), although clinical impact is unknown. We evaluated the association between vigabatrin and predefined brain magnetic resonance imaging (MRI) changes in a large homogenous tuberous sclerosis complex (TSC) cohort and assessed to what extent VABAM-related symptoms were reported in TSC infants. The Dutch TSC Registry and the EPISTOP cohort provided retrospective and prospective data from 80 TSC patients treated with vigabatrin (VGB) before the age of 2 years and 23 TSC patients without VGB. Twenty-nine age-matched non-TSC epilepsy patients not receiving VGB were included as controls. VABAM, specified as T2/fluid-attenuated inversion recovery hyperintensity or diffusion restriction in predefined brain areas, were examined on brain MRI before, during, and after VGB, and once in the controls (at approximately age 2 years). Additionally, the presence of VABAM accompanying symptoms was evaluated. Prevalence of VABAM in VGB-treated TSC patients was 35.5%. VABAM-like abnormalities were observed in 13.5% of all patients without VGB. VGB was significantly associated with VABAM (risk ratio [RR] = 3.57, 95% confidence interval [CI] = 1.43-6.39), whereas TSC and refractory epilepsy were not. In all 13 VGB-treated patients with VABAM for whom posttreatment MRIs were available, VABAM entirely resolved after VGB discontinuation. The prevalence of symptoms was 11.7% in patients with VABAM or VABAM-like MRI abnormalities and 4.3% in those without, implicating no significant association (RR = 2.76, 95% CI = .68-8.77). VABAM are common in VGB-treated TSC infants; however, VABAM-like abnormalities also occurred in children without either VGB or TSC. The cause of these MRI changes is unknown. Possible contributing factors are abnormal myelination, underlying etiology, recurrent seizures, and other antiseizure medication. Furthermore, the presence of VABAM (or VABAM-like abnormalities) did not appear to be associated with clinical symptoms. This study confirms that the well-known antiseizure effects of VGB outweigh the risk of VABAM and related symptoms.

Edonerpic maleate prevents epileptic seizure during recovery from brain damage by balancing excitatory and inhibitory inputs

Functional recovery from brain damage, such as stroke, is a plastic process in the brain. The excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) plays a crucial role in neuronal functions, and the synaptic trafficking of AMPAR is a fundamental mechanism underlying synaptic plasticity. We recently identified a collapsin response mediator protein 2 (CRMP2)-binding compound, edonerpic maleate, which augments rehabilitative training-dependent functional recovery from brain damage by facilitating experience-driven synaptic delivery of AMPARs. In animals recovering from cryogenic brain injury, a potential compensatory area adjacent to the injured region was observed, where the injection of CNQX, an AMPAR antagonist, significantly attenuated functional recovery. In the compensatory brain area of animals recovering from cryogenic injury, the administration of edonerpic maleate enhanced both excitatory and inhibitory synaptic inputs at pyramidal neurons. In contrast, recovered animals that did not receive the drug exhibited augmentation of only excitatory synaptic input. The threshold of picrotoxin-induced epileptic seizure in recovered animals without edonerpic maleate treatment was lower than in intact animals and recovered animals with edonerpic maleate. Thus, edonerpic maleate enhances motor function recovery from brain damage by balancing excitatory and inhibitory synaptic inputs, which helps prevent epileptic seizures during recovery.

Caregiver or Playmate? Fathers' and mothers' brain responses to ball-play with children.

Parents and children often engage in joint play-a domain where mothers and fathers are thought to exhibit disparate behaviors and impact child development via distinct mechanisms. However, little is known about the neural substrates of mother-child and father-child play. In this fMRI study, we sampled thebrain activation of parents of preschoolers (N = 88) during a novel event-related adaptation of the virtual ball-tossing game "Cyberball." Mothers (N = 40) and fathers (N = 48) played "Cyberball" ostensibly with their own and an unrelated child, whoconsecutively included, excluded, and reincluded parents. We found that overall, exclusion yielded comparable neural activations in mothers and fathers associated with mentalizing, saliency, and emotionprocessing. We also observed a parent gender effect in several brain areas. While mothers exhibited increased reward- and attention-related activity during inclusion, fathers displayed increased mentalizing-related activity during exclusion. Furthermore,we tested parents' response to reinclusion, which revealed a selective decrease in reward-related activity. Finally, exploratory analyses showed that parental involvement was positively correlated with parental brain activity within attention- and mentalizing-related areas during inclusion, as opposed to other game phases, and that an anxious parenting style was associated with increased neural sensitivity for game events involving their own child. Overall, our study elucidates the common and distinct neural networks that mothers and fathers engage during play interactions with their children, supporting theories that postulate only a partial differentiation of paternal and maternal parenting systems.

Variations in BDNF and Their Role in the Neurotrophic Antidepressant Mechanisms of Ketamine and Esketamine: A Review.

Brain-derived neurotrophic factor (BDNF) is critical for neuroplasticity, synaptic transmission, and neuronal survival. Studies have implicated it in the pathophysiology of depression, as its expression is significantly reduced in brain areas such as the prefrontal cortex and hippocampus in patients with depression. Our narrative review focuses on the relationship between BDNF, ketamine, and esketamine, specifically by summarizing human studies investigating BDNF variations in patients treated with these two drugs. BDNF plays a pivotal role in neuroplasticity and neurotrophic mechanisms that can be enhanced by traditional antidepressants, which have been shown to increase BDNF levels both peripherally and in targeted brain regions. Ketamine and its S-enantiomer, esketamine, exert both rapid and sustained antidepressant effects through activation of glutamate-related pathways, with neurotrophic effects involving BDNF, as demonstrated in experimental studies. However, clinical findings have shown mixed results, with most indicating an increase in plasma BDNF in patients treated with intravenous ketamine, although some studies contradict these findings. In addition to this, there are few studies of BDNF and esketamine. Currently, the limited number of studies suggests the need for further research, including larger sample sizes and investigations of BDNF and intranasal esketamine, which has been approved by several regulatory agencies for the treatment of treatment-resistant depression.

The food dye Tartrazine disrupts vascular formation both in zebrafish larvae and in human primary endothelial cells

Tartrazine (E102) is a controversial coloring agent whose potential impacts on human health are not fully understood. Our study reveals the vascular disrupting effects of tartrazine (TTZ) on developing zebrafish embryos in vivo and on human umbilical vein endothelial cells in vitro. The dye was shown to cause dose-dependent hemorrhages in zebrafish embryos. Analyzing transgenic zebrafish harboring fluorescent endothelial cells revealed that TTZ treatment disrupted cell organization into vessels in both the sub-intestinal vein and the brain area. Assays on human umbilical vein endothelial cells demonstrated that TTZ inhibited endothelial proliferation, tube formation, and migration in a dose-dependent manner. Taken together, our results indicate for the first time that TTZ can affect endothelial cell properties, possibly by disrupting Rho family GTPase pathways which control the cytoskeleton. Our finding provides a credible explanation for many reported human health impacts and offers prospective applications for biomedicine.

A case report of a mild neurologic deficit with extensive poststroke damage to the subdominant brain hemisphere: analysis of data obtained from magnetic resonance tractography, functional magnetic resonance imaging, and electroencephalography

The severity of damage to different brain areas, including the cortex, can vary significantly in the associated neurologic deficit and reduction in the quality of life, often regardless of the lesion volume. The localization of the abnormalities plays a large part. Lesions of the dominant and subdominant hemispheres can differ greatly in both clinical features and effects on the patient’s quality of life. In this case report, a patient admitted for rehabilitation after two ischemic strokes underwent neurological and neuropsychological examination, complex instrumental diagnostics using electroencephalography, magnetic resonance imaging, computed tomography perfusion, magnetic resonance tractography, and functional magnetic resonance imaging. The patient had minimal left-sided hemiparesis, impaired regulation of voluntary activity, mild decrease in neurodynamic indicators, mildly impaired concentration, and a critical view of his condition. Neuroimaging findings demonstrated extensive postinfarction damage to the right subdominant hemisphere of the brain in the middle cerebral artery circulation. A nonconformity between the brain damage volume and the severity of its clinical signs was observed. Based on functional examination data, the dominant hemisphere was determined, and restructuring the functional centers was suggested. This clinical case was compared with similar ones, and their relationship with the data was analyzed. Information that expands the knowledge of the topography of the altered zones involved in motor and speech functions and the ability to perform arithmetic counting was obtained.

The regulative role and mechanism of BNST in anxiety disorder.

Anxiety disorders, common yet impactful emotional disturbances, significantly affect physical and mental health globally. Many neuron circuits are associated with anxiety regulation like septo-hippocampal loop, amygdala(AMYG), bed nucleus of the stria terminalis (BNST), ventral hippocampus (vHPC), and brain regions like medial prefrontal cortex (mPFC). However, the concrete mechanism of anxiety disorder in BNST is relatively unknown. Recent research showed BNST plays a critical role in modulating anxiety owing to its anatomical location and special circuit characteristics, which are considered to be a hub in the limbic system regulating anxiety. BNST consists with multiple subregions, which can project separately into different brain regions and exert projecting independently to various brain regions with distinct regulatory effects. Moreover, multiple signal pathways in BNST are reported to play significant roles in regulating anxiety and stress behavior. This review briefly describes anxiety disorders and subdivisions and functions of BNST, focusing on the main neural circuits that serve as fundamental pathways in both the genesis and potential treatment of anxiety disorders and the molecular mechanism of BNST on anxiety. The complexity of structures and mechanisms has facilitated the development of imaging techniques. Innovative multimodal imaging techniques, such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), have non-invasively illuminated BNST activities and their functional connections with other brain areas. These methodologies provide a deeper understanding of how BNST responds to anxiety-inducing stimuli, offering invaluable insights into its complex role in anxiety regulation. The continued exploration of BNST in anxiety research promises not only to elucidate fundamental neurobiological mechanisms but also to foster advancements in clinical treatments for anxiety disorders.

Anodal High-definition Transcranial Direct Current Stimulation Over the Left (but not Right) Parietal Cortex Facilitates Mental Arithmetic

AbstractNon-invasive brain stimulation (NIBS) techniques such as transcranial direct current stimulation (tDCS) allow for investigating the functional involvement of specific brain areas in mental arithmetic. In this study, we employed for the first time high-definition (HD)-tDCS, which offers enhanced spatial precision, to explore the functional roles of the left and right intraparietal sulcus (IPS) in mental arithmetic. A total of 25 participants underwent anodal left IPS, anodal right IPS, and sham stimulation in separate sessions in counterbalanced order while solving single- and multi-step addition and subtraction problems. We found that stimulation of the left IPS, but not the right IPS or sham stimulation, improved arithmetic performance speed. These results provide further evidence for the functional involvement of the left IPS in a broad range of arithmetic tasks and highlight the potential of NIBS for cognitive enhancement.