scholarly journals Using electrodermal activity to validate multilevel pain stimulation in healthy volunteers evoked by thermal grills

2020 ◽  
Vol 319 (3) ◽  
pp. R366-R375
Author(s):  
Hugo F. Posada-Quintero ◽  
Youngsun Kong ◽  
Kimberly Nguyen ◽  
Cara Tran ◽  
Luke Beardslee ◽  
...  
Keyword(s):  
Tissue Injury ◽  
Electrodermal Activity ◽  
Pain Scale ◽  
Potential Harm ◽  
Electric Pulses ◽  
Stimulation Level ◽  
Highly Correlated ◽  
The Brain ◽  
Different Levels ◽  
Assessment Research

We have tested the feasibility of thermal grills, a harmless method to induce pain. The thermal grills consist of interlaced tubes that are set at cool or warm temperatures, creating a painful “illusion” (no tissue injury is caused) in the brain when the cool and warm stimuli are presented collectively. Advancement in objective pain assessment research is limited because the gold standard, the self-reporting pain scale, is highly subjective and only works for alert and cooperative patients. However, the main difficulty for pain studies is the potential harm caused to participants. We have recruited 23 subjects in whom we induced electric pulses and thermal grill (TG) stimulation. The TG effectively induced three different levels of pain, as evidenced by the visual analog scale (VAS) provided by the subjects after each stimulus. Furthermore, objective physiological measurements based on electrodermal activity showed a significant increase in levels as stimulation level increased. We found that VAS was highly correlated with the TG stimulation level. The TG stimulation safely elicited pain levels up to 9 out of 10. The TG stimulation allows for extending studies of pain to ranges of pain in which other stimuli are harmful.

Abstract TP147: Central Post Stroke Pain: A Systematic Review

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Jonathan Singer ◽  
Alyssa Conigliaro ◽  
Elizabeth Spina ◽  
Susan Law ◽  
Steven Levine
Keyword(s):  
Systematic Review ◽  
Brain Imaging ◽  
Pain Scale ◽  
Post Stroke ◽  
Underlying Causes ◽  
Single Question ◽  
Thalamic Region ◽  
The Brain ◽  
A Current

Background: Central Post Stroke Pain (CPSP) is reportedly due to strokes in the thalamic region (Dishinbition Theory); however, the Central Imbalance Theory states that CPSP is due to damage to the spinothalamic pathway (STP). Aims: 1) Clarify the role of thalamic strokes and STP damage in CPSP patients. 2) Gain a current understanding of anatomic substrates, brain imaging, and treatment of CPSP. Methods: Two independent reviewers systematically reviewed PUBMED, CINAHL and Web of Science for studies including original, clinical studies and randomized controlled trials (RCTs) using PRISMA guidelines. Studies had to assess CPSP, using a single question or pain scale. Results: Search from January – July 2016, identifying 731 publications. We extracted data from 23 studies and categorized the articles’ aims into 4 sections: somatosensory deficits (5 studies), STP (3 studies), brain imaging (7 studies), and RCTs (8 studies). Somatosensory studies showed high rates of CPSP; however, the underlying causes of these deficits were unclear. Most studies did not refer to stroke location as playing a role in CPSP, but that pathways may. STP studies displayed consistent evidence that the STP plays a major role in CPSP, delineating that CPSP can occur even when the stroke is not in the thalamic region but in other regions (e.g. cerebellum, basal ganglia, medulla). Four of the brain imaging studies found CPSP not related and 3 found it was related to thalamic strokes. All 7 studies had major limitations including sample size, no control groups, and selection bias. RCTs were mostly negative, but brain stem and motor cortex stimulation studies showed the most promise. Conclusions: While CPSP has been linked to the thalamic region since the early 1900’s, the peer-reviewed literature showed equivocal results when examining location of stroke. Our systematic review suggests damage to the STP is associated with CPSP and this could provide insights into mechanisms and treatment. Moreover, historical connection of strokes in the thalamic region and CPSP should be reevaluated as many studies noted that strokes in other regions of the brain also produce CPSP.

Protective effect of Saccharomyces cerevisiae in Rattus norvegicus Ischemic Stroke Model

2021 ◽  
pp. 5785-5789
Author(s):  
Dedy Budi Kurniawan ◽  
Mokhamad Fahmi Rizki Syaban ◽  
Arinal Mufidah ◽  
Muhammad Unzila Rafsi Zulfikri ◽  
Wibi Riawan
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ischemic Stroke ◽  
Brain Tissue ◽  
Tissue Injury ◽  
Intervention Group ◽  
Positive Control ◽  
Positive Control Group ◽  
Control Group ◽  
Hematopoietic Stem ◽  
The Brain

Stroke is one of the leading causes of morbidity and mortality in all ages. Ischemic stroke activates excitotoxic glutamate cascade leading to brain tissue injury. Saccharomyces cerevisiae is a unicellular yeast widely found in nature. S. cerevisiae is neuroprotective and able to increase the differentiation of hematopoietic stem cells (HSCs) into neuronal cells. it may increase levels of neuroprotectant BDNF in the brain tissue, therefore increase the protection of neurons. BDNF may prevent glutamate-driven excitotoxicity by reducing glutamate levels. This study uses a randomized post-test only controlled group design. In this in vivo study, rodent models of ischemic stroke were divided into five groups comprising of the negative control group, positive control group, intervention group 1 (18mg/kgBW), intervention group 2 (36mg/kgBW) and intervention group 3 (72 mg/kgBW). Groups treated with Saccharomyces cerevisiae extract showed significantly increased BDNF levels in the brain tissue, and the expression of the glutamate level was significantly reduced (P <0.05) compared to the positive control group. Thus Saccharomyces cerevisiae has a promising potential to become a therapy against ischemic stroke disease. however further research is needed regarding the efficacy and toxicity of Saccharomyces cerevisiae.

scholarly journals The Distribution of Skull Score and Skull Density Ratio in Tremor Patients for MR-Guided Focused Ultrasound Thalamotomy

2021 ◽  
Vol 15 ◽  
Author(s):  
Kevin Wen-Kai Tsai ◽  
Jui-Cheng Chen ◽  
Hui-Chin Lai ◽  
Wei-Chieh Chang ◽  
Takaomi Taira ◽  
...  
Keyword(s):  
Trabecular Bone ◽  
Cortical Bone ◽  
Focused Ultrasound ◽  
Density Ratio ◽  
Ct Images ◽  
Image Feature ◽  
Cumulative Distribution ◽  
Invasive Surgical Approach ◽  
Highly Correlated ◽  
The Brain

ObjectiveMagnetic resonance-guided focused ultrasound (MRgFUS) is a minimum-invasive surgical approach to non-incisionally cause the thermos-coagulation inside the human brain. The skull score (SS) has already been approved as one of the most dominant factors related to a successful MRgFUS treatment. In this study, we first reveal the SS distribution of the tremor patients, and correlate the SS with the image feature from customized skull density ratio (cSDR). This correlation might give a direction to future clinical studies for improving the SS.MethodsTwo hundred and forty-six patients received a computed tomography (CT) scan of the brain, and a bone-enhanced filter was applied and reconstructed to a high spatial resolution CT images. The SS of all patients would be estimated by the MRgFUS system after importing the reconstructed CT images into the MRgFUS system. The histogram and the cumulative distribution of the SS from all the patients were calculated to show the percentage of the patients whose SS lower than 0.3 and 0.4. The same CT images of all patients were utilized to calculated the cSDR by first segmented the trabecular bone and the cortical bone from the CT images and divided the average trabecular bone intensity (aTBI) by the average cortical bone intensity (aCBI). The Pearson’s correlations between the SS and the cSDR, aTBI, and the aCBI were calculated, respectively.ResultsThere were 19.19 and 50% of the patient who had the SS lower than the empirical threshold 0.3 and 0.4, respectively. The Pearson’s correlation between the SS and the cSDR, aCBI, and the aTBI were R = 0.8145, 0.5723, and 0.8842.ConclusionHalf of the patients were eligible for the MRgFUS thalamotomy based on the SS, and nearly 20% of patients were empirically difficult to achieve a therapeutic temperature during MRgFUS. The SS and our cSDR are highly correlated, and the SS had a higher correlation with aTBI than with aCBI. This is the first report to explicitly reveal the SS population and indicate a potential way to increase the chance to achieve a therapeutic temperature for those who originally have low SS.

scholarly journals Attention controls multisensory perception via 2 distinct mechanisms at different levels of the cortical hierarchy

PLoS Biology ◽  
2021 ◽  
Vol 19 (11) ◽  
pp. e3001465
Author(s):  
Ambra Ferrari ◽  
Uta Noppeney
Keyword(s):  
Causal Inference ◽  
Causal Structure ◽  
Multisensory Perception ◽  
Spatial Representations ◽  
Perceptual Inference ◽  
Sensory Signals ◽  
Cortical Hierarchy ◽  
Parietal Cortices ◽  
The Brain ◽  
Different Levels

To form a percept of the multisensory world, the brain needs to integrate signals from common sources weighted by their reliabilities and segregate those from independent sources. Previously, we have shown that anterior parietal cortices combine sensory signals into representations that take into account the signals’ causal structure (i.e., common versus independent sources) and their sensory reliabilities as predicted by Bayesian causal inference. The current study asks to what extent and how attentional mechanisms can actively control how sensory signals are combined for perceptual inference. In a pre- and postcueing paradigm, we presented observers with audiovisual signals at variable spatial disparities. Observers were precued to attend to auditory or visual modalities prior to stimulus presentation and postcued to report their perceived auditory or visual location. Combining psychophysics, functional magnetic resonance imaging (fMRI), and Bayesian modelling, we demonstrate that the brain moulds multisensory inference via 2 distinct mechanisms. Prestimulus attention to vision enhances the reliability and influence of visual inputs on spatial representations in visual and posterior parietal cortices. Poststimulus report determines how parietal cortices flexibly combine sensory estimates into spatial representations consistent with Bayesian causal inference. Our results show that distinct neural mechanisms control how signals are combined for perceptual inference at different levels of the cortical hierarchy.

scholarly journals Partial cortico-hippocampectomy in cats, as therapy for refractory temporal epilepsy: A descriptive cadaveric study

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244892
Author(s):  
Jessica Zilli ◽  
Monika Kressin ◽  
Anne Schänzer ◽  
Marian Kampschulte ◽  
Martin J. Schmidt
Keyword(s):  
Temporal Lobe ◽  
Tissue Injury ◽  
Histopathological Examination ◽  
Hippocampal Sclerosis ◽  
Intraoperative Complications ◽  
Temporal Cortex ◽  
Cadaveric Study ◽  
Vascular Lesions ◽  
Temporal Epilepsy ◽  
The Brain

Cats, similar to humans, are known to be affected by hippocampal sclerosis (HS), potentially causing antiepileptic drug (AED) resistance. HS can occur as a consequence of chronic seizure activity, trauma, inflammation, or even as a primary disease. In humans, temporal lobe resection is the standardized therapy in patients with refractory temporal lobe epilepsy (TLE). The majority of TLE patients are seizure free after surgery. Therefore, the purpose of this prospective cadaveric study is to establish a surgical technique for hippocampal resection in cats as a treatment for AED resistant seizures. Ten cats of different head morphology were examined. Pre-surgical magnetic resonance imaging (MRI) and computed tomography (CT) studies of the animals’ head were carried out to complete 3D reconstruction of the head, brain, and hippocampus. The resected hippocampal specimens and the brains were histologically examined for tissue injury adjacent to the hippocampus. The feasibility of the procedure, as well as the usability of the removed specimen for histopathological examination, was assessed. Moreover, a micro-CT (mCT) examination of the brain of two additional cats was performed in order to assess temporal vasculature as a reason for possible intraoperative complications. In all cats but one, the resection of the temporal cortex and the hippocampus were successful without any evidence of traumatic or vascular lesions in the surrounding neurovascular structures. In one cat, the presence of mechanical damage (a fissure) of the thalamic surface was evident in the histopathologic examination of the brain post-resection. All hippocampal fields and the dentate gyrus were identified in the majority of the cats via histological examination. The study describes a new surgical approach (partial temporal cortico-hippocampectomy) offering a potential treatment for cats with clinical and diagnostic evidence of temporal epilepsy which do not respond adequately to the medical therapy.

scholarly journals Neuropeptides in modulation of Drosophila behavior: how to get a grip on their pleiotropic actions

2019 ◽  
Author(s):  
Dick R Nässel ◽  
Dennis Pauls ◽  
Wolf Huetteroth
Keyword(s):  
Expression Pattern ◽  
Internal State ◽  
Neurosecretory Cells ◽  
Higher Order ◽  
Specific Expression ◽  
Specific Expression Pattern ◽  
Pleiotropic Functions ◽  
Pleiotropic Actions ◽  
The Brain ◽  
Different Levels

Neuropeptides constitute a large and diverse class of signaling molecules that are produced by many types of neurons, neurosecretory cells, endocrines and other cells. Many neuropeptides display pleiotropic actions either as neuromodulators, co-transmitters or circulating hormones, while some play these roles concurrently. Here, we highlight pleiotropic functions of neuropeptides and different levels of neuropeptide signaling in the brain, from context-dependent orchestrating signaling by higher order neurons, to local executive modulation in specific circuits. Additionally, orchestrating neurons receive peptidergic signals from neurons conveying organismal internal state cues and relay these to executive circuits. We exemplify these levels of signaling with four neuropeptides, SIFamide, short neuropeptide F, allatostatin-A and leucokinin, each with a specific expression pattern and level of complexity in signaling.

scholarly journals Leukocyte dynamics after intracerebral hemorrhage in a living patient reveal rapid adaptations to tissue milieu

2020 ◽  
Author(s):  
Brittany A. Goods ◽  
Michael H. Askenase ◽  
Erica Markarian ◽  
Hannah E. Beatty ◽  
Riley Drake ◽  
...  
Keyword(s):  
Intracerebral Hemorrhage ◽  
Single Cell ◽  
Brain Tissue ◽  
Cellular Response ◽  
Tissue Injury ◽  
Brain Inflammation ◽  
Therapeutic Interventions ◽  
Acute Injury ◽  
The Brain ◽  
Over Time

ABSTRACTIntracerebral hemorrhage (ICH) is a devastating form of stroke with a high mortality rate and few treatment options. Discovery of therapeutic interventions has been slow given the challenges associated with studying acute injury, particularly over time, in the human brain. Inflammation induced by exposure of brain tissue to blood appears to be a major part of brain tissue injury. Here we longitudinally profiled blood and cerebral hematoma effluent from a patient enrolled in the Minimally Invasive Surgery with Thrombolysis in Intracerebral Haemorrhage Evacuation (MISTIEIII) trial, offering a rare window into the local and systemic immune responses to acute brain injury. Using single-cell RNA-sequencing, we characterized the local cellular response during ICH in the brain of a living patient at single-cell resolution for the first time. Our analysis revealed rapid shifts in the activation states of myeloid and T cells in the brain over time, suggesting that leukocyte responses are dynamically reshaped by the hematoma microenvironment. Interestingly, the patient had an asymptomatic re-bleed (second local exposure to blood) that our transcriptional data indicated occurred more than 30 hours prior to detection by CT scan. This case highlights the rapid immune dynamics in the brain after ICH and suggests that sensitive methods like scRNA-seq can inform our understanding of complex intracerebral events.

A Three-Component-System Hypothesis of Psychosis

1989 ◽  
Vol 155 (S5) ◽  
pp. 37-39 ◽  
Author(s):  
Hinderk M. Emrich
Keyword(s):  
Human Brain ◽  
Causative Factor ◽  
Microscopic Level ◽  
Point Of View ◽  
Component System ◽  
Pathogenetic Factor ◽  
Pet Scans ◽  
The Brain ◽  
Different Levels

Hypotheses as to the pathogenesis of schizophrenia can be discussed at different levels of a possible manifestation of the causative factor: the macroscopic-morphological, the microscopic-morphological, and the molecular. Some abnormalities have been observed on all of them: e.g. increased ventricular-brain ratios in CT, hypofrontality in SPECT and in glucographic PET-scans, and other macromorphological abnormalities (for reviews cf. Bogerts 1984; Mundt, 1986; Bogerts et al, 1987), gliosis on a microscopic level (Stevens, 1982), and an increased dopamine-binding in in vivo receptor studies (PET as well as in post-mortem studies; Cazzullo, 1988). However, the diversity and variability of these findings point to the view that rather than there being a single distinct pathogenetic factor responsible for the pathogenesis of schizophrenic psychoses, a constitutional disposition exists, which can be described as a functional dysequilibrium within the human brain. From this point of view, schizophrenia would not appear as an inherited disorder of metabolism, but as a weakness of a neurobiological ‘system’, i.e. as an interactional disorder of a complex of networks, in which the interaction between different substructures is labile in such a way that under special conditions (e.g. ‘stress’), a decompensation (functional breakdown) results. In this sense, ‘vulnerability’ to schizophrenia may be interpreted as a consequence of a constitutional deficiency of the brain which results in an inability to stabilise, under specially challenging conditions, the interaction between different substructures of the human brain. Before this ‘functional dysequilibrium-hypothesis’ (which is a special form of a constitutional structural deficiency-hypothesis) is discussed, and before the question is raised as to which are the relevant dysequilibrated components, some indication will be given as to why such an hypothesis appears plausible.

scholarly journals Role of estrogen and stress on the brain-gut axis

2019 ◽  
Vol 317 (2) ◽  
pp. G203-G209 ◽  
Author(s):  
Yanyan Jiang ◽  
Beverley Greenwood-Van Meerveld ◽  
Anthony C. Johnson ◽  
R. Alberto Travagli
Keyword(s):  
Functional Gastrointestinal Disorders ◽  
Clinical Problem ◽  
Visceral Sensitivity ◽  
Physiological Mechanisms ◽  
Acute And Chronic Stress ◽  
Highly Correlated ◽  
The Brain ◽  
Gi Motility

Symptoms of functional gastrointestinal disorders (FGIDs), including fullness, bloating, abdominal pain, and altered gastrointestinal (GI) motility, present a significant clinical problem, with a reported prevalence of 25%–40% within the general population. More than 60% of those affected seek and require healthcare, and affected individuals report a significantly decreased quality of life. FGIDs are highly correlated with episodes of acute and chronic stress and are increased in prevalence and reported severity in women compared with men. Although there is evidence that sex and stress interact to exacerbate FGID symptoms, the physiological mechanisms that mediate these sex-dependent disparities are incompletely understood, although hormonal-related differences in GI motility and visceral sensitivity have been purported to play a significant role in the etiology. In this mini review, we will discuss brain-gut axis control of GI motility and sensitivity, the influence of estrogen on GI motility and sensitivity, and stress modulation of the brain-gut axis.

Saliency-based Rhythmic Coordination of Perceptual Predictions

2020 ◽  
Vol 32 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Qiaoli Huang ◽  
Huan Luo
Keyword(s):  
Temporal Dynamics ◽  
Theta Band ◽  
Behavioral Profile ◽  
Fine Grained ◽  
Attentional Process ◽  
Behavioral Measurement ◽  
Processing Resources ◽  
Rhythmic Coordination ◽  
The Brain ◽  
Different Levels

Objects, shown explicitly or held in mind internally, compete for limited processing resources. Recent studies have demonstrated that attention samples locations and objects rhythmically. Interestingly, periodic sampling not only operates over objects in the same scene but also occurs for multiple perceptual predictions that are held in attention for incoming inputs. However, how the brain coordinates perceptual predictions that are endowed with different levels of bottom–up saliency information remains unclear. To address the issue, we used a fine-grained behavioral measurement to investigate the temporal dynamics of processing of high- and low-salient visual stimuli, which have equal possibility to occur within experimental blocks. We demonstrate that perceptual predictions associated with different levels of saliency are organized via a theta-band rhythmic course and are optimally processed in different phases within each theta-band cycle. Meanwhile, when the high- and low-salient stimuli are presented in separate blocks and thus not competing with each other, the periodic behavioral profile is no longer present. In summary, our findings suggest that attention samples and coordinates multiple perceptual predictions through a theta-band rhythm according to their relative saliency. Our results, in combination with previous studies, advocate the rhythmic nature of attentional process.

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