Cerebral Activity Research Articles

Cerebral bioelectrical activity: neurobiophysical characteristics and their clinical interpretation

Cerebral bioelectrical activity: neurobiophysical characteristics and their clinical interpretation

When the Brain and the Heart Collide: A Complex Diagnostic and Management Dilemma of Coexisting Psychogenic Nonepileptic Seizures and Takotsubo Cardiomyopathy - A Case Report

Epilepsy is a prevalent neurological disorder affecting around one percent of the global population. Accurate diagnosis is paramount for effective treatment, but challenging-to-diagnose seizures require a comprehensive evaluation to exclude other conditions. Psychogenic nonepileptic seizures (PNES) or pseudoseizures are sudden episodes resembling epileptic seizures, but not arising from abnormal cerebral electrical activity. PNES are often misdiagnosed as epilepsy, leading to delayed appropriate psychological therapy and unwarranted antiepileptic medication use. We report a unique case of a patient initially diagnosed and treated as epilepsy, who was later diagnosed with PNES during hospitalization. Additionally, the patient presented Takotsubo cardiomyopathy (TCM), a rare stress-induced cardiomyopathy, posing a diagnostic and management challenge alongside PNES. To the best of our knowledge, this is the first case of coexisting PNES and TCM, which warrants further investigation.

Functional mri in the study of cerebral cortex activation in patients with newly diagnosed depression after acute coronary syndrome

Functional mri in the study of cerebral cortex activation in patients with newly diagnosed depression after acute coronary syndrome

Exposure to Low Levels of Radiofrequency Electromagnetic Fields Emitted from Cell-phones as a Promising Treatment of Alzheimer's Disease: A Scoping Review Study.

Alzheimer's disease (AD) is one of the most significant public health concerns and tremendous economic challenges. Studies conducted over the past decades show that exposure to radiofrequency electromagnetic fields (RF-EMFs) may relieve AD symptoms. To determine if exposure to RF-EMFs emitted by cellphones affect the risk of AD. In this review, all relevant published articles reporting an association of cell phone use with AD were studied. We systematically searched international datasets to identify relevant studies. Finally, 33 studies were included in the review. Our review discusses the effects of RF-EMFs on the amyloid β (Aβ), oxidative stress, apoptosis, reactive oxygen species (ROS), neuronal death, and astrocyte responses. Moreover, the role of exposure parameters, including the type of exposure, its duration, and specific absorption rate (SAR), are discussed. Progressive factors of AD such as Aβ, myelin basic protein (MBP), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and neurofilament light polypeptide (NFL) were decreased. While tau protein showed no change, factors affecting brain activity such as glial fibrillary acidic protein (GFAP), mitogen-activated protein kinases (MAPKs), cerebral blood flow (CBF), brain temperature, and neuronal activity were increased. Exposure to low levels of RF-EMFs can reduce the risk of AD by increasing MAPK and GFAP and decreasing MBP. Considering the role of apoptosis in AD and the effect of RF-EMF on the progression of the process, this review indicates the positive effect of these exposures.

Single-cell profiling reveals preferential reduction of memory B cell subsets in cladribine patients that correlates with treatment response

Background: Cladribine is a highly effective immunotherapy that is applied in two short-term courses over 2 years and reduces relapse rate and disease progression in patients with relapsing multiple sclerosis (MS). Despite the short treatment period, cladribine has a long-lasting effect on disease activity even after recovery of lymphocyte counts, suggesting a yet undefined long-term immune modulating effect. Objectives: Our aim was to provide a more profound understanding of the detailed effects of cladribine, also with regard to the patients’ therapy response. Design: We performed an open-labeled, explorative, prospective, single-arm study, in which we examined the detailed lymphocyte subset development of MS patients who received cladribine treatment over 2 years. Methods: We performed in-depth profiling of the effects of cladribine on peripheral blood lymphocytes by flow cytometry, bulk RNA sequencing of sorted CD4+ T cells, CD8+ T cells, and CD19+ B cells as well as single-cell RNA sequencing of peripheral blood mononuclear cells in a total of 23 MS patients before and at different time points up to 24 months after cladribine treatment. Data were correlated with clinical and cranial magnetic resonance imaging (MRI) disease activity. Results: Flow cytometry revealed a predominant and sustained reduction of memory B cells compared to other B cell subsets after cladribine treatment, whereas T cell subsets were slightly reduced in a more uniform pattern. The overall transcriptional profile of total blood B cells exhibited reduced expression of proinflammatory and T cell activating genes, while single-cell transcriptomics revealed that gene expression within each B cell cluster did not change over time. Stable patients displayed stronger reductions of selected memory B cell clusters as compared to patients with clinical or cerebral MRI disease activity. Conclusion: We describe a pronounced and sustained effect of cladribine on the memory B cell compartment, and the resulting change in B cell subset composition causes a significant alteration of B cell transcriptional profiles resulting in reduced proinflammatory and T cell activating capacities. The extent of reduction in selected memory B cell clusters by cladribine may predict treatment response.

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

S-06-4: IMPACT OF ANTI-HYPERTENSIVE THERAPY ON CEREBRAL FUNCTIONAL NETWORKS AND CONNECTIVITY

It is well known that hypertension is the main modifiable risk factor leading to cognitive impairment and various forms of dementia. Leveraging functional MRI it has been possible to characterize hypertensives brain functional connectivity, a main feature of cerebral activation and health measurable by resting-state functional MRI. This characterization let us analyze how pathological conditions influence the cognitive processes and the spontaneous organization of brain activity, and have shown that hypertensive patients even before showing signs of vascular dementia have alterations in cerebral connections compared to normotensive patients. Our current question is whether different classes of antihypertensives, differentiated in mechanism of action and potential to cross the blood brain barrier may have different impact on cerebral functional organization. 42 hypertensives with controlled hypertension (SBP< 140mmHg e DBP< 90mmHg) were subjected to resting-state functional MRI. Functional connectivity was elaborated by CONN, according to an analysis pipeline to build functional connectivity networks matrices calculating the cross-correlation of BOLD signal among different brain regions. The obtained network of connections has been analyzed by general linear model, to implement regression models that highlight the connections in the brains modulated by the specific classes of antihypertensives analyzed. The application of regression models with age, sex, BMI, alcohol, smoke, SBP and DBP levels, heart rate as covariates shown that treatment with diuretics modulate a large connectivity network among Salience Network, Default Mode Network and Language Network (Fig. A). Ace-inhibitors treatment is associated with a significant modulation of a connection between Default Mode Network and the FrontoParietal Network (Fig. B), while ARBs are associated to the modulation of connections between Cerebellar and Language Networks (Fig. C). Finally, beta-blockers are associated with connections centered in Dorsal Attention Network and projected to Language and FrontoParietal Networks (Fig. D). Globally, the most relevant functional modulation of the brain is imposed by the use of diuretics, with a possible explanation in the fact that lowering global volume of circulating blood may have a significant impact on cerebral circulation. By this analysis, we will be able to take into account the central and cognitive impact of different antihypertensive drugs on the choice of best personalized treatment of hypertension.

The Effect of Low-frequency Repetitive Transcranial Magnetic Stimulation on Muscle Tone Reduction and Cerebral Activity in Stroke Patients

An intervention program was conducted with two groups of patients who had experienced stroke: one which received low-frequency rTMS and occupational therapy (rTMS-OT Group), and one which received occupational therapy only (OT group). The treatment was provided three times per week for 4 weeks followed by a 1-week evaluation of MEP amplitude and latency, and muscle tone. In an intergroup test of MEP amplitude and latency, and muscle tone, all groups showed increases between pre-and post-test evaluations. As a result of the study, during the treatment intervention of the experimental group and the control group, the experimental group rTMS-OTG and the control OTG group showed MEP amplitudes of 0.161 mV and 0.114 mV, respectively, and the experimental group showed more improvement. The MEP latency of the rTMS-OTG group was -2.83 ms and the MEP latency of the OTG group was -1.49 ms. The experimental group, rTMS-OTG, responded faster. However, in the case of muscle tone evaluation, there was no significant difference between the two groups. In conclusion, we determined that rTMS may be safely applied to the directly damaged cerebral cortex and is considered to be an effective treatment for patients recovering from stroke.

Effects of robot gaze and voice human-likeness on users’ subjective perception, visual attention, and cerebral activity in voice conversations

Robot gaze and voice are essential anthropomorphic features to promote users' engagement in voice conversations. Earlier research chiefly examined how robot gaze and voice human-likeness separately influenced users' subjective perception. When implementing gaze on robots with different human-like voices, there has little evidence of their possible interaction effects, particularly on users' visual attention and cerebral activity, which could help to understand the perceptual and cognitive processing of anthropomorphic features. Therefore, a within-subject experiment of voice conversations with diverse robot gaze (gaze versus no gaze) and human-like voices (high human-like versus low human-like) using subjective reporting, eye-tracker, and fNIRS was conducted. The results showed that the robot with gaze or a high human-like voice evoked more pleasure, higher arousal, more perceived likability, and less negative attitudes. Robot gaze significantly increased users' average fixation durations and total fixation time, while voice human-likeness prolonged first fixation durations. Moreover, the robot with a high human-like voice (or gaze) induced increased activity in the left DLPFC and decreased activity in the right Broca's area than that had no gaze (or a low human-like voice). The results suggest that robot gaze might chiefly capture users' sustained attention, voice human-likeness might attract users' initial attention, and they might jointly influence users' perceptual processing of prosodic features and emotional processing.

SENSORY GATING: BALANCE BETWEEN SLEEP AND LIFE

Sleep is a state of the brain characterized by a low level of vigilance and diminished consciousness. The reaction to external stimuli and the processing of stimuli are attenuated in sleep. During sleep, the reticular thalamic nucleus inhibits at the thalamus the flow of sensory activity from the senses to the cerebral cortex. After arrival at the afferent layer of the primary cortex, the reduced sensory flow is analyzed and personalized by layers of the cortical area and transferred by the corticofugal system back to appropriate subdivisions of the thalamus. Thalamic subdivisions target the information of the senses to related areas of the cerebral cortex, where the messages can be (sub)consciously perceived. When necessary, the sleeper can be awakened by a wake-up call, either by stimuli indicating danger or by personally meaningful stimuli. Evidently, sensory gating in sleep has two main features. First, it is favorable for sleep, by reducing the cerebral brain activity through the reticular thalamic nucleus, and second, it is necessary for the sleepers' safety and well-being, by analyzing the preserved activity on essential or dangerous external elements by the corticofugal system. These two features are analyzed in detail in non-REM sleep as well as in REM sleep. In the latter type of sleep, the process of sensory gating is almost similar to non-REM sleep, despite the enigmatic reconstruction of external stimuli into the dream. With the extended corticofugal system, sleep phenomena as the first-night effect, the occurrence of local sleep and wake states, as well as the unihemispheric sleep are comprehensible.

Mechanistic model for human brain metabolism and its connection to the neurovascular coupling.

The neurovascular and neurometabolic couplings (NVC and NMC) connect cerebral activity, blood flow, and metabolism. This interconnection is used in for instance functional imaging, which analyses the blood-oxygen-dependent (BOLD) signal. The mechanisms underlying the NVC are complex, which warrants a model-based analysis of data. We have previously developed a mechanistically detailed model for the NVC, and others have proposed detailed models for cerebral metabolism. However, existing metabolic models are still not fully utilizing available magnetic resonance spectroscopy (MRS) data and are not connected to detailed models for NVC. Therefore, we herein present a new model that integrates mechanistic modelling of both MRS and BOLD data. The metabolic model covers central metabolism, using a minimal set of interactions, and can describe time-series data for glucose, lactate, aspartate, and glutamate, measured after visual stimuli. Statistical tests confirm that the model can describe both estimation data and predict independent validation data, not used for model training. The interconnected NVC model can simultaneously describe BOLD data and can be used to predict expected metabolic responses in experiments where metabolism has not been measured. This model is a step towards a useful and mechanistically detailed model for cerebral blood flow and metabolism, with potential applications in both basic research and clinical applications.

Two‐phase classification: ANN and A‐SVM classifiers on motor imagery BCI

AbstractBrain–Computer Interfaces (BCIs) based on Electroencephalograms (EEG) monitor mental activity with the ultimate objective of allowing people to communicate with computers only via their thoughts. Users must create precise cerebral activity patterns that the system uses as control signals to do this. A common activity used to elicit such signals is Motor Imagery (MI), in which certain signals are created in the sensorimotor cortex while imagining the movements. The three phases of the traditional EEG–BCI processing pipeline are preprocessing, feature extraction, and classification. We provide categorization advances and track performance gains in 4‐class MI‐based BCIs. In this study, 4‐class MI events are produced via an illusory elevation of the left hand, right hand, feet, and tongue. Finally, a two‐phase classification technique is provided with ANN classifiers being used in the first phase to discriminate between different pair‐wise MI tasks. Secondly, an adaptive SVM classifier is used to assess the user's end task based on the weighted outputs of the classifiers. An adaptive classifier is one technique to maintain consistency in performance, reduce training time, and eliminate non‐stationaries, all of which are required for efficient BCI performance. The suggested approach outperformed conventional two‐stage classification algorithms on MI data, according to experimental findings. The average classification accuracy of this technique is 96% for datasets BCI competition IV 2a. This is a 4% improvement over the comparison approach.

A study on alterations in functional activity in migraineurs during the interictal period

Migraine is a recurrent disease in which the cumulative effect of repeated pain attacks over a long period of time causes changes in brain function. Although there are some studies focusing on the interictal period of migraine, the reproducibility of these results is poor. Therefore, we intend to use a data-driven functional connectivity (FC) approach to probe the alterations in cerebral functional activity during the interictal period, as well as underlying no-task mechanisms of inducing headache attack in migraine patients. In the current research, 24 episodic migraine patients and 23 healthy controls (HCs) were recruited. By analyzing the magnitude of regional homogeneity (ReHo) and low-frequency fractional fluctuation (fALFF), We identified alterations in spontaneous brain activity in migraineurs, including the bilateral middle frontal gyrus, left postcentral, and right lingual gyrus. Thereafter such abnormalities were selected as seeds (ROIs) for FC analysis to further explore the underlying changes between ROIs and the whole brain areas. Compared with HCs, FC between the right middle frontal gyrus with the left precuneus cortex, and bilateral thalamus were enhanced in migraineurs. In addition, increased FC has been showed between the left postcentral gyrus with the bilateral thalamus. Furthermore, negative correlation existed between fALFF values of the left middle frontal gyrus and the pain intensity of migraine attacks (r = −0.4578, p = 0.0245). In summary, abnormal FC between the bilateral thalamus and right middle frontal gyrus, or the left retrocentral gyrus may occur between attacks in migraineurs, which may be the basis for sensory integration and pain regulation dysfunction. Thus, this could become a promising biomarker for the early diagnosis and evaluation of migraine in the interictal period, and provide a novel view for further investigation of the pathogenesis and etiology of recurrent migraine.

Emerging Materials, Wearables, and Diagnostic Advancements in Therapeutic Treatment of Brain Diseases.

Among the most critical health issues, brain illnesses, such as neurodegenerative conditions and tumors, lower quality of life and have a significant economic impact. Implantable technology and nano-drug carriers have enormous promise for cerebral brain activity sensing and regulated therapeutic application in the treatment and detection of brain illnesses. Flexible materials are chosen for implantable devices because they help reduce biomechanical mismatch between the implanted device and brain tissue. Additionally, implanted biodegradable devices might lessen any autoimmune negative effects. The onerous subsequent operation for removing the implanted device is further lessened with biodegradability. This review expands on current developments in diagnostic technologies such as magnetic resonance imaging, computed tomography, mass spectroscopy, infrared spectroscopy, angiography, and electroencephalogram while providing an overview of prevalent brain diseases. As far as we are aware, there hasn't been a single review article that addresses all the prevalent brain illnesses. The reviewer also looks into the prospects for the future and offers suggestions for the direction of future developments in the treatment of brain diseases.

Red blood cells as glucose carriers to the human brain: Modulation of cerebral activity by erythrocyte exchange transfusion in Glut1 deficiency (G1D)

Red blood cells circulating through the brain are briefly but closely apposed to the capillary endothelium. We hypothesized that this contact provides a nearly direct pathway for metabolic substrate transfer to neural cells that complements the better characterized plasma to endothelium transfer. While brain function is considered independent of normal fluctuations in blood glucose concentration, this is not borne out by persons with glucose transporter I (GLUT1) deficiency (G1D). In them, encephalopathy is often ameliorated by meal or carbohydrate administration, and this enabled us to test our hypothesis: Since red blood cells contain glucose, and since the red cells of G1D individuals are also deficient in GLUT1, replacing them with normal donor cells via exchange transfusion could augment erythrocyte to neural cell glucose transport via mass action in the setting of unaltered erythrocyte count or plasma glucose abundance. This motivated us to perform red blood cell exchange in 3 G1D persons. There were rapid, favorable and unprecedented changes in cognitive, electroencephalographic and quality-of-life measures. The hypothesized transfer mechanism was further substantiated by in vitro measurement of direct erythrocyte to endothelial cell glucose flux. The results also indicate that the adult intellect is capable of significant enhancement without deliberate practice. ClinicalTrials.gov registration: NCT04137692 https://clinicaltrials.gov/ct2/show/NCT04137692

Hyperactivity of the default mode network in schizophrenia and free energy: A dialogue between Freudian theory of psychosis and neuroscience.

The economic conceptualization of Freudian metapsychology, based on an energetics model of the psyche's workings, offers remarkable commonalities with some recent discoveries in neuroscience, notably in the field of neuroenergetics. The pattern of cerebral activity at resting state and the identification of a default mode network (DMN), a network of areas whose activity is detectable at baseline conditions by neuroimaging techniques, offers a promising field of research in the dialogue between psychoanalysis and neuroscience. In this article we study one significant clinical application of this interdisciplinary dialogue by looking at the role of the DMN in the psychopathology of schizophrenia. Anomalies in the functioning of the DMN have been observed in schizophrenia. Studies have evidenced the existence of hyperactivity in this network in schizophrenia patients, particularly among those for whom a positive symptomatology is dominant. These data are particularly interesting when considered from the perspective of the psychoanalytic understanding of the positive symptoms of psychosis, most notably the Freudian hypothesis of delusions as an "attempt at recovery." Combining the data from research in neuroimaging of schizophrenia patients with the Freudian hypothesis, we propose considering the hyperactivity of the DMN as a consequence of a process of massive reassociation of traces occurring in schizophrenia. This is a process that may constitute an attempt at minimizing the excess of free energy present in psychosis. Modern models of active inference and the free energy principle (FEP) may shed some light on these processes.

Estimation of Respiratory Rate from Functional Near-Infrared Spectroscopy (fNIRS): A New Perspective on Respiratory Interference

Respiration is recognized as a systematic physiological interference in functional near-infrared spectroscopy (fNIRS). However, it remains unanswered as to whether it is possible to estimate the respiratory rate (RR) from such interference. Undoubtedly, RR estimation from fNIRS can provide complementary information that can be used alongside the cerebral activity analysis, e.g., sport studies. Thus, the objective of this paper is to propose a method for RR estimation from fNIRS. Our primary presumption is that changes in the baseline wander of oxygenated hemoglobin concentration (O2Hb) signal are related to RR. fNIRS and respiratory signals were concurrently collected from subjects during controlled breathing tasks at a constant rate from 0.1 Hz to 0.4 Hz. Firstly, the signal quality index algorithm is employed to select the best O2Hb signal, and then a band-pass filter with cut-off frequencies from 0.05 to 2 Hz is used to remove very low- and high-frequency artifacts. Secondly, troughs of the filtered O2Hb signal are localized for synthesizing the baseline wander (S1) using cubic spline interpolation. Finally, the fast Fourier transform of the S1 signal is computed, and its dominant frequency is considered as RR. In this paper, two different datasets were employed, where the first one was used for the parameter adjustment of the proposed method, and the second one was solely used for testing. The low mean absolute error between the reference and estimated RRs for the first and second datasets (2.6 and 1.3 breaths per minute, respectively) indicates the feasibility of the proposed method for RR estimation from fNIRS. This paper provides a novel view on the respiration interference as a source of complementary information in fNIRS.

Cerebral microvascular matrix metalloproteinase-3 (MMP3) contributes to vascular injury after stroke in female diabetic rats

Diabetes exacerbates hemorrhagic transformation (HT) after stroke and worsens clinical outcomes. Female patients with diabetes are at a greater risk of stroke and worsened recovery. We have shown that activation of matrix metalloprotease 3 (MMP3) in hyperglycemic settings mediates HT in male rats. In light of our recent findings that diabetic female rats develop greater HT, the current study was designed to test the hypotheses that: 1) cerebral microvascular MMP3 activation contributes to poor functional outcomes and increased hemorrhagic transformations (HT) after ischemic stroke, and 2) MMP3 inhibition can improve functional outcomes in female diabetic rats. Female control and diabetic Wistar rats were subjected to 60 min of middle cerebral artery occlusion (MCAO). One cohort of diabetic animals received a single dose of MMP3 inhibitor (UK356618; 15 mg/kg; iv) or vehicle after reperfusion. Neurobehavioral outcomes, brain infarct size, edema, HT, and MMPs were measured in brain tissue. Diabetic rats had significant neurological deficits on Day 3 after stroke. MMP3 expression and enzyme activity were significantly increased in both micro and macro vessels of diabetic animals. MMP3 inhibition improved functional outcomes and reduced brain edema and HT scores. In conclusion, cerebral endothelial MMP3 activation to vascular injury in female diabetic rats. Our findings identify MMP3 as a potential therapeutic target in diabetic stroke.

Problem Solving by Agricultural Extension Students with Various Levels of Creativity through a Neurocognitive Lens

The cultivation of agricultural extension talent is key to sustainable agricultural development because it can help create unique economic relationships, add new knowledge and skills to traditional agriculture, identify marketing advantages in emerging markets, and promote the transition to a sustainable society. This study identified the activated brain regions and thought patterns of agricultural extension students when they performed numerical, spatial, and verbal intelligence tasks. The cerebral activity of the student participants was captured through electroencephalography to analyze their activated brain regions and thought patterns during the problemidentification and resolution-reaching phases. A total of 36 participants were recruited and divided into high-creativity (HC) and low-creativity groups to analyze differences in their thought patterns. The results indicated that numeric problem solving activated the frontoparietal network and was associated with a high level of self-generated thought. The function of evaluating creativity was inhibited in the HC group, and the participants engaged in divergent semantic processing during the numeric task. Spatial problem solving activated the frontal regions and was associated with intensive visual search tasks. The HC group exhibited suppressed creativity evaluation and analogical reasoning. Verbal problem solving activated the frontoparietal regions and was associated with verbal memory, semantic-based word processing, and self-generated thought. Creative associations in the verbal task were enhanced in the HC group. This study adopted innovative approaches to address a complex topic that has not been thoroughly investigated but is essential for the theoretical development of both neurocognitive science and agricultural sustainability.

Cerebral cortical activity after withdrawal of life-sustaining measures in critically ill patients

Establishing when cerebral cortical activity stops relative to circulatory arrest during the dying process will enhance trust in donation after circulatory determination of death. We used continuous electroencephalography and arterial blood pressure monitoring prior to withdrawal of life sustaining measures and for 30 min following circulatory arrest to explore the temporal relationship between cessation of cerebral cortical activity and circulatory arrest. Qualitative and quantitative EEG analyses were completed. Among 140 screened patients, 52 were eligible, 15 were enrolled, 11 completed the full study, and 8 (3 female, median age 68 years) were included in the analysis. Across participants, EEG activity stopped at a median of 78 (Q1=-387, Q3=111) seconds before circulatory arrest. Following withdrawal of life sustaining measures there was a progressive reduction in electroencephalographic amplitude (p=.002), spectral power (p=.008), and coherence (p=.003). Prospective recording of cerebral cortical activity in imminently dying patients is feasible. Our results from this small cohort suggest that cerebral cortical activity does not persist after circulatory arrest. Confirmation of these findings in a larger multicenter study are needed to help promote stakeholder trust in donation after circulatory determination of death.