Neural Disturbances Research Articles

Modulation of GABAergic neurons in acute epilepsy using sonogenetics.

Epilepsy, a neurological disorder caused by hypersynchronous neural disturbances, has traditionally been treated with surgery, pharmacotherapy, and neuromodulation techniques such as deep brain stimulation and vagus nerve stimulation. However, these methods are often limited by invasiveness, off-target effects, and poor resolution. We present a noninvasive alternative utilizing sonogenetics to selectively stimulate γ-aminobutyric acid (GABA)ergic neurons in the amygdala through engineered auditory-sensing protein, mPrestin (N7T, N308S), in a pentylenetetrazole-induced rat model. Activation of GABAergic neurons induced by the sonication with 0.5-MHz transcranial ultrasound can modulate epileptiform activity by 50 %. Electrophysiological recordings confirmed effective neuromodulation and persistent seizure suppression up to 60 min post-treatment without tissue damage, inflammation, or apoptosis. This sonogenetic approach offers a promising, safe method for epilepsy management by targeting GABAergic neurons.

Structural and functional whole brain changes in autism spectrum disorder at different age stages.

Autism spectrum disorder (ASD) is a developmental disorder involving regional changes and local neural disturbances. However, few studies have investigated the dysfunctional phenomenon across different age stages. This study explores the structural and functional brain changes across different developmental stages in individuals with ASD, focusing on childhood (6-12 years), adolescence (12-18 years), and adulthood (18 + years). Using a comprehensive set of neuroimaging metrics, including modulated and non-modulated voxel-based morphometry (VBM), regional homogeneity (ReHo), amplitude of low-frequency fluctuation (ALFF), and fractional ALFF (fALFF), we identified significant stage-specific alterations in both VBM and functional measurements. Our results reveal that ASD is associated with progressive and stage-specific abnormalities in brain structure and function, with distinct patterns emerging at each developmental stage. Specifically, we observed significant modulated VBM reductions in the precuneus, lentiform nucleus, and inferior parietal lobule, accompanied by increases in the midbrain and sub-gyral regions. Moreover, we observed unmodulated VBM increment in regions including lentiform nucleus and thalamus. Functionally, ReHo analyses demonstrated disrupted local synchronization in the medial frontal gyrus, while ALFF and fALFF metrics highlighted altered spontaneous brain activity in the sub-gyral and sub-lobar. Finally, correlation analyses revealed that stage-specific findings are closely linked to clinical social- and behavior-related scores, with VBM in the inferior parietal lobule and putamen as well as ReHo in supplemental motor area being significantly associated with restrictive repetitive behaviors in childhood. These findings underscore the importance of considering age-specific brain changes when studying ASD and suggest that targeted interventions may be necessary at different developmental stages.

Self-construal modulates default mode network connectivity in refugees with PTSD

BackgroundWhile self-construal and posttraumatic stress disorder (PTSD) are independently associated with altered self-referential processes and underlying default mode network (DMN) functioning, no study has examined how self-construal affects DMN connectivity in PTSD. MethodsA final sample of 93 refugee participants (48 with DSM-5 PTSD or sub-syndromal PTSD and 45 matched trauma-exposed controls) completed a 5-minute resting state fMRI scan to enable the observation of connectivity in the DMN and other core networks. A self-construal index was calculated by substracting scores on the collectivistic and individualistic sub-scales of the Self Construal Scale. ResultsIndependent components analysis identified 9 active networks-of-interest, and functional network connectivity was determined. A significant interaction effect between PTSD and self-construal index was observed in the anterior ventromedial DMN, with spatial maps localizing this to the left ventromedial prefrontal cortex (vmPFC), extending to the ventral anterior cingulate cortex. This effect revealed that connectivity in the vMPFC showed greater reductions in those with PTSD with higher levels of collectivistic self-construal. LimitationsThis is an observational study and causality cannot be assumed. The specialized sample of refugees means that the findings may not generalize to other trauma-exposed populations. ConclusionsSuch a finding indicates that self-construal may shape the core neural architecture of PTSD, given that functional disruptions to the vmPFC underpin the core mechanisms of extinction learning, emotion dysregulation and self-referential processing in PTSD. Results have important implications for understanding the universality of neural disturbances in PTSD, and suggest that self-construal could be an important consideration in the assessment and treatment of post-traumatic stress reactions.

Exploring the neurofunctional impairments and cognitive biases concerning food and body related stimuli in anorexia nervosa: An integrated EEG and eye-tracking study protocol.

Patients with Anorexia Nervosa (AN) exhibit significant cognitive and neural disturbances compared to healthy individuals when processing food and body-related stimuli. These disturbances not only contribute to the manifestation and chronification of their pathological eating behaviour but also underscore the complex interplay of cognitive, emotional, and neurobiological factors in AN. However, the precise underlying cognitive and neural mechanisms of these disturbances remain a compelling area of investigation. This study presents a protocol developed for conducting a cross-sectional quasi-experimental study using a mixed model ANOVA approach with a crossover design. Our participants will consist of 20 patients with an active diagnosis of AN, 20 Overweight/obese individuals, and 20 Healthy Controls (HCs) with a normal BMI. An integrated eye-tracking and EEG methodology will be used in conjunction, with the primary aim of assessing participants' cognitive and neural processing towards high and low-calorie food stimuli. On an exploratory level, by utilizing the same methods, the present study will also investigate AN patients' responses towards high weight, normal weight, low weight, and self-body pictures, as well as towards images from the International Affective Picture System (IAPS) characterized by elevated valence and arousal levels. Additionally, behavioural methods such as yes or no questions, and self-reported questionnaires will be administered. The EEG and eye-tracking data will be analysed at early (50-300 ms) and late (350-500 ms) time intervals. The investigation of the underlying cognitive and neural processes employed by patients with AN during the processing of food and body-related stimuli can help us develop a better understanding of the cognitive and neural mechanisms that contribute to the manifestation and maintenance of the disorder and assist in the development of more effective screening methods. Ethical approval for the study has been obtained by the Cyprus National Bioethics Committee on 27.04.2023 (ΕΕΒΚ/ΕΠ/2023/19), and by the University of Cyprus (20.02.2023). Written informed consent will be obtained from all participants.

Luteolin amends neural neurotransmitters, antioxidants, and inflammatory markers in the cerebral cortex of Adderall exposed rats

BackgroundAdderall is a central nervous system stimulant while luteolin has neuroprotective activity. This study aimed to determine whether luteolin can amend neural neurotransmitters, antioxidants, and inflammatory markers in the cerebral cortex of Adderall exposed rats. MethodsThirty-six male albino rats were divided into 6 equal groups, Control, Luteolin (1 g/kg)-treated, and Luteolin (2 g/kg)-treated groups: normal rats were orally administrated once a day with 2 ml distilled water, luteolin (1 g/kg), and luteolin (2 g/kg), respectively for 4 weeks. Adderall rats, Adderall rats + luteolin (1 g/kg)-treated, and Adderall rats + luteolin (2 g/kg)-treated groups: normal rats were orally administrated once a day with 10 mg/kg of Adderall, 3 days/week for 4 weeks, then these rats orally administrated daily once a day with 2 ml of distilled water, luteolin (1 g/kg), and luteolin (2 g/kg), respectively for another 4 weeks. Results and conclusionAdderall decreased superoxide dismutase, glutathione peroxidase, catalase, NADPH oxidase, interleukin-10, serotonin, dopamine, norepinephrine, γ-aminobutyric acid, and acetylcoline estrase but increased malondialdehyde, conjugated dienes, oxidative index, tumour necrosis factor-α, interleukin-1β, and interleukin-6 levels in the cerebral cortex. Adderall increased the expression of glial fibrillary acidic protein, ionized calcium binding adaptor molecule 1, and anti-calbindin in the cerebral cortex of Adderall-treated rats. In Adderall-treated rats, daily oral administration of luteolin for 4 weeks brought all these parameters back to values that were close to control where higher dose was more effective than lower dose. The importance of this research is to provide natural compound that amends Adderall-related neural disturbances and this natural compound is cheap, avaliable without any side effect and it does not interfer with Adderall efficiency.

The Modulatory Effects of Atomoxetine on Aberrant Connectivity During Attentional Processing in Cocaine Use Disorder

BackgroundCocaine use disorder is associated with cognitive deficits that reflect dysfunctional processing across neural systems. Because there are currently no approved medications, treatment centers provide behavioral interventions that have only short-term efficacy. This suggests that behavioral interventions are not sufficient by themselves to lead to the maintenance of abstinence in patients with cocaine use disorder. Self-control, which includes the regulation of attention, is critical for dealing with many daily challenges that would benefit from medication interventions that can ameliorate cognitive neural disturbances. MethodsTo address this important clinical gap, we conducted a randomized, double-blind, placebo-controlled, crossover design study in patients with cocaine use disorder (n = 23) and healthy control participants (n = 28). We assessed the modulatory effects of acute atomoxetine (40 mg) on attention and conflict monitoring and their associated neural activation and connectivity correlates during performance on the Eriksen flanker task. The Eriksen flanker task examines basic attentional processing using congruent stimuli and the effects of conflict monitoring and response inhibition using incongruent stimuli, the latter of which necessitates the executive control of attention. ResultsWe found that atomoxetine improved task accuracy only in the cocaine group but modulated connectivity within distinct brain networks in both groups during congruent trials. During incongruent trials, the cocaine group showed increased task-related activation in the right inferior frontal and anterior cingulate gyri, as well as greater network connectivity than the control group across treatments. ConclusionsThe findings of the current study support a modulatory effect of acute atomoxetine on attention and associated connectivity in cocaine use disorder.

Individual differences in visual evoked potential latency are associated with variance in brain tissue volume in people with multiple sclerosis: An analysis of brain function-structure correlates

Visual evoked potentials (VEP) index visual pathway functioning, and are often used for clinical assessment and as outcome measures in people with multiple sclerosis (PwMS). VEPs may also reflect broader neural disturbances that extend beyond the visual system, but this possibility requires further investigation. In the present study, we examined the hypothesis that delayed latency of the P100 component of the VEP would be associated with broader structural changes in the brain in PwMS. We obtained VEP latency for a standard pattern-reversal checkerboard stimulus paradigm, in addition to Magnetic Resonance Imaging (MRI) measures of whole brain volume (WBV), gray matter volume (GMV), white matter volume (WMV), and T2-weighted fluid attenuated inversion recovery (FLAIR) white matter lesion volume (FLV). Correlation analyses indicated that prolonged VEP latency was significantly associated with lower WBV, GMV, and WMV, and greater FLV. VEP latency remained significantly associated with WBV, GMV, and WMV even after controlling for the variance associated with inter-ocular latency, age, time between VEP and MRI assessments, and other MRI variables. VEP latency delays were most pronounced in PwMS that exhibited low volume in both white and gray matter simultaneously. Furthermore, PwMS that had delayed VEP latency based on a clinically relevant cutoff (VEP latency ≥ 113 ms) in both eyes had lower WBV, GMV, and WMV and greater FLV in comparison to PwMS that had normal VEP latency in one or both eyes. The findings suggest that PwMS that have delayed latency in both eyes may be particularly at risk for exhibiting greater brain atrophy and lesion volume. These analyses also indicate that VEP latency may index combined gray matter and white matter disturbances, and therefore broader network connectivity and efficiency. VEP latency may therefore provide a surrogate marker of broader structural disturbances in the brain in MS.

Dopaminergic and serotonergic changes in rabbit fetal brain upon repeated gestational exposure to diesel engine exhaust.

Limited studies in humans and in animal models have investigated the neurotoxic risks related to a gestational exposure to diesel exhaust particles (DEP) on the embryonic brain, especially those regarding monoaminergic systems linked to neurocognitive disorders. We previously showed that exposure to DEP alters monoaminergic neurotransmission in fetal olfactory bulbs and modifies tissue morphology along with behavioral consequences at birth in a rabbit model. Given the anatomical and functional connections between olfactory and central brain structures, we further characterized their impacts in brain regions associated with monoaminergic neurotransmission. At gestational day 28 (GD28), fetal rabbit brains were collected from dams exposed by nose-only to either a clean air or filtered DEP for 2h/day, 5days/week, from GD3 to GD27. HPLC dosage and histochemical analyses of the main monoaminergic systems, i.e., dopamine (DA), noradrenaline (NA), and serotonin (5-HT) and their metabolites were conducted in microdissected fetal brain regions. DEP exposure increased the level of DA and decreased the dopaminergic metabolites ratios in the prefrontal cortex (PFC), together with sex-specific alterations in the hippocampus (Hp). In addition, HVA level was increased in the temporal cortex (TCx). Serotonin and 5-HIAA levels were decreased in the fetal Hp. However, DEP exposure did not significantly modify NA levels, tyrosine hydroxylase, tryptophan hydroxylase or AChE enzymatic activity in fetal brain. Exposure to DEP during fetal life results in dopaminergic and serotonergic changes in critical brain regions that might lead to detrimental potential short-term neural disturbances as precursors of long-term neurocognitive consequences.

An overview of seizures and epilepsy in rabbits: etiological differences and clinical management

World Health Organization data suggest that neurological disorders are an important and growing cause of morbidity. One of the most common neurological disorder affecting people is epilepsy. Many companion animal neurological diseases share epidemiologic, pathophysiologic and clinical features with their human counterparts. In companion animals, affected species are mostly dogs, cats and rabbits. Seizure is defined as the clinical manifestation of abnormal electrical activity in the brain. Epilepsy is a brain disease characterized by the psychological, cognitive, social and environmental consequences of seizures. The epileptic seizures are recurrent events characterized by behavioral alterations that reflect the underlying neural mechanisms of the disease. In most cases, the disease can be diagnosed by anamnesis or observing the seizure. There are many reviews and researches about epilepsy and epileptic seizures in companion animals such as dogs and cats but not in rabbits. There are several causes of epilepsy in rabbits including viral, bacterial, parasitic, metabolic, respiratory, cardiovascular, nutritional, toxic, traumatic, enviromental and non-epileptic causes. Rabbits can be considered suitable for seizure and epilepsy investigations due to their recurrent seizures with low risk of death. As mentioned, there are several causes of epilepsy in rabbits but still to elucidate the exact mechanism of epilepsy and epileptic seizures in rabbits more studies need to be carried out. Despite the advances in the disease management, epilepsy is still an important cause of disability and mortality in both humans and companion animals. As tonic-clonic seizures with brainstem origin mostly affect children, epileptic seizures in rabbits may be a good model for further studies. Key words: Brain disease, epilepsy, neural disturbances, behavioral alterations, rabbit, seizure.

Evaluation of the effect of the lateralized inferior alveolar nerve isolation and bone grafting on the nerve function and implant stability. (Randomized Clinical Trial).

The inferior alveolar nerve lateralization (IANL), although allows for an implant full-length mandibular height engagement, coincides with depleting the buccal bone support and sensory deficits. This study aims to assess whether interposing a bone graft coupled with securing a collagen membrane separation between the inferior alveolar nerve (IAN) and the underlying dental implants would preserve the nerve function, enhance the implant stability, and minimize the radiographic marginal bone loss. Eighteen patients with 30 atrophic mandibular edentulous ridges were subjected to IANL after being randomly assigned to two treatment modalities which consisted of 15 patients each. The (control group) utilized conventional IANL in direct contact with 20 implants. The (test group) implemented the IAN collagen-membrane wrapping and interposing bone graft to overlay 23 implants. The neural function, the radiographic marginal bone loss, and the implant stability quotient were assessed and compared 6 months postoperatively. All the patients regained their full neurosensory function after 6 months, with statistically nonsignificant differences between both groups throughout the follow-up period. The mean marginal bone loss in the test group was (0.42 ± 0.09) mm versus (0.38 ± 0.14) mm for the control group, which was statistically similar (P= 0.401). The 6-month postoperative mean implant stability quotient values of the test group recorded (74.73 ± 2.68) versus (74.73 ± 1.79) for the control group, which was statistically nonsignificant with a value of P= 0.626. The interposed bone graft, coupled with the collagen membrane isolation, neither subsided the neural disturbances nor enhanced the secondary implant stability and marginal bone loss.

Sleep-Wake Cycle and EEG-Based Biomarkers during Late Neonate to Adult Transition.

During the transition from neonate to adulthood, brain maturation establishes coherence between behavioral states—wakefulness, non-rapid eye movement, and rapid eye movement sleep. In animal models few studies have characterized and analyzed cerebral rhythms and the sleep–wake cycle in early ages, in relation to adulthood. Since the analysis of sleep in early ages can be used as a predictive model of brain development and the subsequent emergence of neural disturbances in adults, we performed a study on late neonatal mice, an age not previously characterized. We acquired longitudinal 24 h electroencephalogram and electromyogram recordings and performed time and spectral analyses. We compared both age groups and found that late neonates: (i) spent more time in wakefulness and less time in non-rapid eye movement sleep, (ii) showed an increased relative band power in delta, which, however, reduced in theta during each behavioral state, (iii) showed a reduced relative band power in beta during wakefulness and non-rapid eye movement sleep, and (iv) manifested an increased total power over all frequencies. The data presented here might have implications expanding our knowledge of cerebral rhythms in early ages for identification of potential biomarkers in preclinical models of neurodegeneration.

At the Heart of Neurological Dimensionality: Cross-Nosological and Multimodal Cardiac Interoceptive Deficits.

Neurological nosology, based on categorical systems, has largely ignored dimensional aspects of neurocognitive impairments. Transdiagnostic dimensional approaches of interoception (the sensing of visceral signals) may improve the descriptions of cross-pathological symptoms at behavioral, electrophysiological, and anatomical levels. Alterations of cardiac interoception (encompassing multidimensional variables such as accuracy, learning, sensibility, and awareness) and its neural correlates (electrophysiological markers, imaging-based anatomical and functional connectivity) have been proposed as critical across disparate neurological disorders. However, no study has examined the specific impact of neural (relative to autonomic) disturbances of cardiac interoception or their differential manifestations across neurological conditions. Here, we used a computational approach to classify and evaluate which markers of cardiac interoception (behavioral, metacognitive, electrophysiological, volumetric, or functional) offer the best discrimination between neurological conditions and cardiac (hypertensive) disease (model 1), and among neurological conditions (Alzheimer's disease, frontotemporal dementia, multiple sclerosis, and brain stroke; model 2). In total, the study comprised 52 neurological patients (mean [standard deviation] age = 55.1 [17.3] years; 37 women), 25 cardiac patients (age = 66.2 [9.1] years; 13 women), and 72 healthy controls (age = 52.65 [17.1] years; 50 women). Cardiac interoceptive outcomes successfully classified between neurological and cardiac conditions (model 1: >80% accuracy) but not among neurological conditions (model 2: 53% accuracy). Behavioral cardiac interoceptive alterations, although present in all conditions, were powerful in differentiating between neurological and cardiac diseases. However, among neurological conditions, cardiac interoceptive deficits presented more undifferentiated and unspecific disturbances across dimensions. Our result suggests a diffuse pattern of interoceptive alterations across neurological conditions, highlighting their potential role as dimensional, transdiagnostic markers.

Neural Correlates of Subjective Recollection of Socially Relevant Information in Schizophrenia

Individuals with schizophrenia demonstrate poor recognition memory, even when information is socially relevant. The neural disturbances associated with responses to information that is subjectively known versus unknown that contribute to this impairment have not been elucidated.

Disturbances across whole brain networks during reward anticipation in an abstinent addiction population

The prevalent spatial distribution of abnormalities reported in cognitive fMRI studies in addiction suggests there are extensive disruptions across whole brain networks. Studies using resting state have reported disruptions in network connectivity in addiction, but these studies have not revealed characteristics of network functioning during critical psychological processes that are disrupted in addiction populations. Analytic methods that can capture key features of whole brain networks during psychological processes may be more sensitive in revealing additional and widespread neural disturbances in addiction, that are the provisions for relapse risk, and targets for medication development. The current study compared a substance addiction (ADD; n = 83) group in extended abstinence with a control (CON; n = 68) group on functional MRI (voxel-wise activation) and global network (connectivity) measures related to reward anticipation on a monetary incentive delay task. In the absence of group differences on MID performance, the ADD group showed reduced activation predominantly across temporal and visual regions, but not across the striatum. The ADD group also showed disruptions in global network connectivity (lower clustering coefficient and higher characteristic path length), and significantly less connectivity across a sub-network comprising frontal, temporal, limbic and striatal nodes. These results show that an addiction group in extended abstinence exhibit localised disruptions in brain activation, but more extensive disturbances in functional connectivity across whole brain networks. We propose that measures of global network functioning may be more sensitive in highlighting latent and more widespread neural disruptions during critical psychological processes in addiction and other psychiatric disorders.

Gait measurement in chronic mild traumatic brain injury: A model approach

IntroductionMild traumatic brain injury (mTBI) can impact gait, with deficits linked to underlying neural disturbances in cognitive, motor and sensory systems. Gait is complex as it is comprised of multiple characteristics that are sensitive to underlying neural deficits. However, there is currently no clear framework to guide selection of gait characteristics in mTBI. This study developed a model of gait in chronic mTBI and replicated this in a separate group of controls, to provide a comprehensive and structured methodology on which to base gait assessment and analysis. MethodsFifty-two people with chronic mTBI and 59 controls completed a controlled laboratory gait assessment; walking for two minutes back and forth over a 13 m distance while wearing five wirelessly synchronized inertial sensors. Thirteen gait characteristics derived from the inertial sensors were selected for entry into the principle component analysis based on previous literature, robustness and novelty. Principle component analysis was then used to derive domains (components) of gait. ResultsFour gait domains were derived for our chronic mTBI group (variability, rhythm, pace and turning) and this was replicated in a separate control cohort. Domains totaled 80.8% and 77.4% of variance in gait for chronic mTBI and controls, respectively. Gait characteristic loading was unambiguous for all features, with the exception of gait speed in controls that loaded on pace and rhythm domains. ConclusionThis study contributes a four component model of gait in chronic mTBI and controls that can be used to comprehensively assess and analyze gait and underlying mechanisms involved in impairment, or examine the influence of interventions.

Global downregulation of pigmentation-associated genes in human premature hair graying.

Premature hair graying, or canities, is a complex multi-factorial process with negative effects on affected individuals. The aim of the present study was to investigate the possible underlying mechanisms of premature hair graying at the genetic level. A total of 5 unrelated Han Chinese individuals presenting with premature hair graying (25–40 years old, with >1% hair affected) were enrolled in the present study. RNA sequencing was performed to identify gene expression changes between the follicular cells of grey and black hair from the cohort. A total of 127 differentially expressed genes (DEGs) were identified. These DEGs were overrepresented in categories associated with the pigmentation pathway, with a decreased expression of key genes responsible for melanin synthesis. Of note, the decreased expression of certain transcription factors and the increased expression of certain precursor microRNAs observed may explain for the downregulation of certain other DEGs, which were identified as their targets via Starbase v2 and Integrated Motif Activity Response Analysis. The DEGs were also enriched in terms associated with the nervous system, indicating that neural disturbances may also have certain roles in premature hair graying. Of note, five of the downregulated DEGs were associated with aging according to the JenAge Aging Factor Database. To the best of our knowledge, the present study was the first genome-wide survey of the gene expression profile associated with premature hair graying. Dysfunction of the melanin biosynthesis pathway is probably the direct cause of hair graying and the present results provide valuable clues for further functional and mechanistic investigation.

Introduction to the Toxins Special Issue on “Novel Issues in Uremic Toxicity”

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18.4 CHARACTERIZING LARGE-SCALE NETWORK DYSCONNECTIVITY IN SCHIZOPHRENIA: MODELING ALTERED E/I BALANCE

BackgroundNeuropsychiatric disorders alter the structure and function of neural circuits and distributed neural networks, which leads to profound behavioral disability such as working memory impairment. Non-invasive neuroimaging tools have matured to reliably detect neural systems-level disturbances in neuropsychiatric disorders. However, mechanistic mapping from neural circuit pathology to abnormal behavior remains out of reach for most psychiatric conditions. We focus on the emerging field of ‘computational psychiatry’ to close these gaps from the perspective of E/I imbalance in schizophrenia with an emphasis on understanding large-Scale network dysconnectivity in schizophrenia.MethodsFirst, we apply computational microcircuit models to understand cognitive and neural system-level disturbances in schizophrenia as a function of altered E/I balance. In turn, the focus is placed on pharmacological neuroimaging as a powerful causal tool to probe neural circuit perturbations. Specific recent neuroimaging studies are discussed that use the NMDA receptor antagonist, ketamine, to probe glutamate synaptic dysfunction associated with schizophrenia. We leverage resting-state neuroimaging advances to inform biomarker development for network alterations in schizophrenia given its ease of data collection and lack of task-based confounds.ResultsPharmacological and clinical results implicate alterations in cortico-striato-thalamic circuits, which might constitute a final common pathway of neural system disturbances in schizophrenia. Results indicate that this functional marker appears in at-risk states, chronic patients, and following pharmacological manipulations following ketamine. Computational simulations implicate altered E/I balance in cortical microcircuits as a parsimonious upstream mechanism.DiscussionThe combined use of biophysical computational modeling, extended to large-scale neural system simulations, has proven particularly powerful to draw inferences about neural circuit alterations that may be ‘driving’ the resting-state dysconnectivity and cognitive deficits in schizophrenia. In summary, present data illustrates a framework for linking experimental studies in humans with computational models and pharmacological probes will advance to effort to bridge cellular, systems, and clinical neuroscience approaches to psychiatric disorders.

White Matter Tract Alterations in Drug-Naïve Parkinson's Disease Patients With Impulse Control Disorders.

Impulse control disorders (ICDs) are relatively frequent in patients with Parkinson’s disease (PD), although it is still unclear whether an underlying pathological process plays a significant role in the development of ICD in PD apart from dopaminergic replacement therapy. In this study, we have investigated alterations of white matter tract in drug-naïve PD patients with ICDs via diffusion MRI connectometry. Our results showed that disrupted connectivity in the complex network of dynamic connections between cerebellum, basal ganglia, cortex, and its spinal projections serves as the underlying neuropathology of ICD in PD not interfered with the contribution of dopaminergic replacement therapy. These findings provide the first evidence on involved white matter tracts in the neuropathogenesis of ICD in drug-naïve PD population, supporting the hypothesis that neural disturbances intrinsic to PD may confer an increased risk for ICDs. Future studies are needed to validate the attribution of the impaired corticocerebellar network to impulsivity in PD.

Irritants, Irritancy and Irritant Induced Asthma

An irritant represents a non-corrosive chemical that causes a reversible non-immunologic inflammatory reaction after direct contact with the skin, eyes, nose and/or respiratory system. There are numerous reactions to irritants including change in spirometry, elevated exhaled breath levels of nitric oxide, enhancement of the response to allergen provocation and alteration of antioxidant defenses. Irritancy prompts an “inflammatory soup” of signaling molecules leading to tissue changes characterized by infiltration of mononuclear inflammatory cells, vascular congestion, augmented blood flow, contiguous edema with leaking of plasma, glandular hyper secretion and nervous hyperresponsiveness. Acute irritant-induced asthma, also referred to as Reactive Airways Dysfunction Syndrome (RADS), is a non-allergic type of asthma presenting without a prior time-period of latency. The manifestations of RADS begin within 24 h following a single massive exposure to an irritating gas, vapor or fume resulting in continuing airway inflammation, changed airway remodeling, persistent structural changes, neural disturbances and unrelenting airway hyperresponsiveness. Recommendation is that RADS or any serious inhalation exposure be handled in a hospital setting. Serial bronchoscopic assessments assist management decisions. Management requires astute judgment and skill for a rapidly changing clinical scenario. The influence of odors and emotion in the pathogenesis irritant-induced inhalational responses is significant.