Changes In Latency Research Articles

Accumulation of advanced oxidative protein products exacerbate satellite glial cells activation and neuropathic pain

BackgroundNeuropathic pain (NP) is a debilitating condition caused by lesion or dysfunction in the somatosensory nervous system. Accumulation of advanced oxidation protein products (AOPPs) is implicated in mechanical hyperalgesia. However, the effects of AOPPs on NP remain unclear.MethodsA rat model of NP was established by chronic constriction injury (CCI) and employed to evaluate the changes of mechanical withdrawal threshold, thermal and cold withdrawal latency, as well as AOPPs levels. The effects of AOPPs on the activation of satellite glial cells (SGCs) in the dorsal root ganglion (DRG), receptor for advanced glycation end-products (RAGE) expression, and NF-κB signaling pathway activation were also investigated using western blotting, immunofluorescence, and the Fluo4-AM fluorescence probe for calcium signaling. Additionally, oxidative stress levels and inflammatory cytokine production in SGCs, triggered by AOPPs exposure, were measured through the DCFH-DA probe for ROS detection and ELISA kits for cytokine quantification.ResultsCCI significantly elevated the AOPPs levels in the plasma and sciatic nerve and caused AOPPs accumulation in the DRG. Exogenous AOPPs activated SGCs, increased reactive oxygen species and inflammatory response, upregulated the RAGE, and activated NF-κB signaling. The RAGE inhibitor FPS-ZM1 effectively inhibited AOPPs-induced SGC activation. Additionally, AOPPs intervention worsened CCI-induced hyperalgesia and neuroinflammation in vivo.ConclusionThese results indicate that AOPPs exacerbate the SGC activation and NP following nerve injury, and AOPPs accumulation might play an important role in the pathogenesis of NP.

The effect of bilingualism on obligatory components of auditory late responses in young adults: a cross-sectional study

IntroductionBilingualism significantly contributes to neuroplasticity in the brain, with research indicating enhanced auditory processing in bilingual individuals. Obligatory sensory components of the auditory late responses (ALRs) reflect primary and secondary auditory cortex activity, serving as an electrophysiological measure of auditory processing. This study aims to compare ALRs' obligatory components (P1-N1-P2) in bilingual (Turkish-Persian) and monolingual (Persian) young adults.MethodThis cross-sectional study analyzed ALRs in 28 monolingual and 28 bilingual participants aged 19 to 30 years, using a 70 dB nHL speech stimulus (/da/). ALRs were recorded monaurally with insert earphones. The study then compared the mean latency and amplitude of P1- N1- P2 complex in the right and left ear between two groups.ResultThe study revealed shorter latency for all three ALRs components in bilingual participants compared to monolinguals. This difference was statistically significant (P-value < 0.05) for N1 with right ear stimulation and P2 with right and left ear stimulations. No significant differences were found in the amplitude of P1-N1 and N1-P2 between the groups.ConclusionThe significant reduction in N1 and P2 latency observed in bilingual subjects' ALRs likely results from neural plasticity. This may enhance neural transmission and accelerate speech sound processing in the respective cortical regions. These latency changes could serve as a cortical neural biomarker distinguishing monolinguals from bilinguals, highlighting the impact of bilingualism on auditory processing efficiency.

Indomethacin and Cefazolin for Physical Exam-Indicated Cerclage to Improve Latency: A Protocol Validation Study.

A single-center randomized trial showed improved latency with use of indomethacin and cefazolin (I/C) during and following exam-indicated cerclage (EIC). The same center recently published a pre/post comparison demonstrating similar results. This research aimed to validate the protocol in a different setting. Retrospective cohort study of singleton pregnancies undergoing EIC at a single center between 2013 and 2022. EIC was performed for painless cervical dilation between 16 and 23 weeks' gestation with dilation ≥1 cm. Exposure was defined as receipt of I/C during and following EIC. The primary outcome was latency ≥ 28 days after cerclage placement. Secondary outcomes included latency; gestational age at delivery; delivery ≤ 28 weeks; preterm premature rupture of membranes; intra-amniotic infection (IAI); and median birth weight. Bivariate statistics were used to analyze data; multivariable regression analyses were used to control for confounders (progesterone use, cervical dilation at time of cerclage placement, history of preterm birth, and prolapsing membranes). EIC was placed in 81 pregnancies and 48 (59%) received I/C. Baseline characteristics did not differ between groups, except that prolapsing membranes were significantly less likely in patients receiving I/C (6.2 vs. 21.2%; p = 0.04). Latency ≥ 28 days occurred in 90% of I/C recipients and 82% of the controls (p = 0.32); this difference remained nonsignificant after controlling for confounders (adjusted relative risk: 1.02 [95% confidence interval: 0.85, 1.21]). I/C recipients had lower rates of IAI (4.2 vs. 24.2%, p = 0.007), even after adjustment (adjusted relative risk: 0.18 [95% confidence interval: 0.04, 0.74]). Other secondary outcomes did not differ. Use of I/C at the time of EIC at this center was not associated with increased latency to delivery (albeit in a small cohort) but was associated with lower rates of intra-amniotic infection. Larger-scale validation studies would be helpful to confirm the value of this intervention. · Indomethacin/cefazolin (I/C) increased latency for exam-indicated cerclage in a trial.. · We performed an observational comparison to validate these findings.. · I/C use for exam-indicated cerclages was associated with decreased intra-amniotic infection.. · I/C was not associated with change in latency.. · Larger-scale validation studies needed to confirm the value of intervention..

Efficacy of Transcutaneous Electrical Acupoint Stimulation on Modulating Upper Extremity Sympathetic Skin Response in Alleviating Cancer Survivors With Chemotherapy-Induced Peripheral Neuropathy: A Propensity Score-Matched Cohort Study.

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of chemotherapy and it is currently intractable We compared the efficacy of transcutaneous electrical acupoint stimulation (TEAS) against non-TEAS groups and investigated the variables that predict effective relief of upper extremity pain in cancer survivors with CIPN. We retrospectively collected data of cancer survivors who developed CIPN between May 2017 to March 2022. All eligible CIPN patients were divided into TEAS group (received TEAS) and non-TEAS group (did not receive TEAS) in our department. A 1:1 ratio propensity score matching (PSM) was used to balance the baseline features. The change of numerical rating scale (NRS), Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2), and sympathetic skin response (SSR) parameters are all assessed after treatment. The procedure was considered a clinically effective relief if the patients' NRS scores were reduced by 50% or more, and overall patients with effective relief were all counted after treatment. Furthermore, a multivariable logistic regression model was utilized to evaluate the predictors of effective relief following CIPN treatment. A total of 102 cancer survivors with CIPN were analyzed after PSM (51 in each group). The change of NRS, SF-MPQ-2, SSR latency and SSR amplitude in TEAS group were significantly higher than those in non-TEAS group at 3weeks after therapy (all P<0.01). In addition, the effective relief rate was significantly higher in TEAS group than in non-TEAS group (P=0.026). Multivariate logistic regression on the total study cohort showed that TEAS group (OR 2.783, P = 0.025) and the baseline SSR amplitude of the upper extremity <1265µV (OR 12.191, P = 0.000) were independent predictive factors for the clinical efficacy. TEAS significantly decreased the severity of CIPN. TEAS group and baseline SSR amplitude of the upper extremity <1265µV were the independent predictive factors for the clinical efficacy after treatment.

Impact of repeated intranasal gentamicin irrigation on auditory brainstem evoked potentials in rats.

Gentamicin is a bactericidal aminoglycoside antibiotic that broadly targets Gram-negative microbes. Both human and animal studies have shown that administration of gentamicin is ototoxic by several routes of administration and results in sensorineural hearing loss due to damaged hair cell at the base of the cochlea. However, gentamicin is also administered intranasally to treat sinusitis in humans, but no animal studies have examined ototoxicity of gentamicin administered via this route. We hypothesized that intranasal irrigation of gentamicin will result in ototoxicity and impaired auditory function similar to systemic delivery. We investigated this hypothesis in Sprague-Dawley rats that received intranasal irrigations of gentamicin or saline from postnatal day (P) 21-31. We examined auditory function by assessing brainstem auditory evoked potentials in response to both broadband clicks and pure tone-pips (4, 8, 16, 24 and 32kHz) on P41. We found significant changes in auditory function in gentamicin-exposed animals. Specifically, gentamicin-exposed animals had significantly higher thresholds in response to both clicks and tone-pips. In response to broadband clicks, there were no changes in latency for waves I through IV. However, we found significantly longer wave and interwave latencies for all waves in response to the 24kHz tone-pip. Together, these findings suggest that intranasal administration of gentamicin results in impaired auditory function consistent with other routes of delivery.

Comparing Effects of Aromatherapy with Five Herbs Essential Oils on PCPA-induced Insomnia Mice.

Delayed treatment of insomnia-related symptoms can harm physical health and increase the psychological burden. In addition to oral medications and some physical therapies, aromatherapy can help overcome some treatment-related side effects. Herein, parachlorophenylalanine (PCPA)-induced insomnia was established in Kunming (KM) mice, which were subjected to aromatherapy using five plants (Jasminum sambac, Magnolia denudata, Rosa rugosa, Aloysia citriodora, and Abies balsamea) essential oils (EOs). To determine the sleep-inducing effect of the five EOs, the rate of change in body weight, sleep latency, and total sleep time in mice were measured. Specific serum indices were used to evaluate the therapeutic effects of the tested drugs and PCPA modeling. Gas chromatography-mass spectrometry (GC-MS) was employed to identify active components in EOs. The five EOs contained multiple identical constituents and were rich in terpenoids, such as α-farnesene (28.42%), linalool (68.84%), and citronellol (23.78%). The EOs exhibiting varying effects on insomnia-induced weight loss. Nissl staining was used to examine and the number of neurons was elevated in the EO-treated groups when compared with the PCPA-induced group; however, the neuronal number was reduced in the hypothalamic tissues of the R. rugosa EO (RREO)-treated group. All EOs upregulated the expression of 5-HT1A and GABAARα1, as demonstrated by immunohistochemistry, western blotting, and reverse transcription-quantitative PCR results. In addition, EOs of A. citriodora and A. balsamea significantly upregulated the expression of 5HT1A protein, whereas EOs of J. sambac and M. denudata exerted significantly different effects when compared with the model group, as determined by western blotting.

The H-reflex study of the flexor carpi radialis muscle in healthy individuals.

This study aimed to investigate the physiological and anatomical factors influencing the flexor carpi radialis (FCR) H-reflex and to establish reference values for FCR H-reflex parameters in relation to these factors. The FCR H-reflexes, elicited by median nerve stimulation, were assessed in 80 healthy individuals both at rest and during isometric voluntary contraction (IVC). Multiple linear regression analyses were performed with H-reflex parameters as the dependent variables, while age, gender, height, arm length, and weight were included as independent variables. The FCR H-reflex was recorded bilaterally in nearly all healthy individuals (76 out of 80) during IVC, while it could be obtained in only 35% (28 out of 80) of these individuals at rest. During IVC, the maximum H-reflex amplitude (Hmax) and its ratio to the maximum M-response amplitude (Hmax/Mmax ratio) were significantly increased (p < 0.001). However, there were no changes in H-reflex latency, latency difference, conduction velocity (HRCV), or amplitude ratio (p > 0.05). In both conditions, age and arm length were the most important factors affecting H-reflex latency (p < 0.001), while HRCV was influenced only by age (p < 0.01). Women exhibited shorter H-reflex latencies (p < 0.01), and both Hmax amplitude and Hmax/Mmax ratio were higher in women during IVC (p < 0.05). The H-reflex amplitude ratio during IVC showed a tendency to decrease with age (p < 0.05). These findings suggest that FCR H-reflexes are more reliably elicited during IVC, and that both physiological and anatomical factors should be considered when assessing H-reflex abnormalities.

Impaired brainstem auditory evoked potentials after in utero exposure to high dose paracetamol exposure

Paracetamol is an analgesic and antipyretic medication regarded as the safest over-the-counter pain and fever relief option during pregnancy. Paracetamol and its metabolites are known to reach the developing fetus through direct placental transfer and can cross the blood brain barrier. Several recent, large-scale epidemiologic studies suggest that in utero paracetamol exposure can increase the risk of neurodevelopmental conditions, including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD) and developmental delay (DD). Since auditory processing deficits are a common feature of ASD, we hypothesized that animals exposed to paracetamol in utero will have impaired auditory brainstem function. We investigated this hypothesis by recording and analyzing click-evoked auditory brainstem responses (ABR) at postnatal day 21 and 29 in Sprague-Dawley rats. In utero exposure to high dose paracetamol exposure had no impact on body or brain weight. However, high dose paracetamol exposure did significantly delay ear opening and resulted in elevated ABR thresholds, and longer wave and interwave latencies. These changes in wave latency extended to the highest click intensity tested but were most severe near threshold. This data suggests that development and function of the auditory brainstem may be impacted by high dose paracetamol exposure and that simple, non-invasive tests of auditory function have utility as an early screening tool for neurodevelopmental disorders.

Perinatal outcomes based on number of digital exams in patients with PPROM.

ACOG recommends speculum exams, rather than digital exams, for evaluation of the cervix after preterm prelabor rupture of membranes (PPROM). However, in clinical practice, digital exams may be necessary. We examined whether increasing numbers of digital exams were associated with adverse outcomes in PPROM. This was a single center retrospective cohort study of patients admitted between 2019 and 2021 with PPROM at 24-34 weeks gestation. The primary outcome was intraamniotic infection and inflammation (triple I), compared between patients who had <1 or >2 digital exams during expectant management of PPROM. Secondary outcomes included latency, antepartum events, and other maternal and neonatal morbidities. Groups were compared using univariate analysis and Cox proportional hazards model to account for time between admission and delivery and potential confounders. Of 125 patients included in the analysis, 46 (36.8%) had < 1 and 79 (63.2%) had  2 digital exams. There was no significant difference in triple I between groups (adjusted hazard ratio [aHR] 1.03, 95% confidence interval (CI) 0.47, 2.26). There were no significant differences in composite maternal or neonatal morbidities or latency from admission to delivery between groups (8 days (interquartile range (IQR) 3, 14) vs. 6 days (IQR 3, 12)). There was a higher rate of spontaneous labor as the indication for delivery in the group with 2 exams (aHR 2.07, 95% CI 1.04, 4.11). In this retrospective cohort study, ≥2 digital exams during expectant management of PPROM was not associated with change in infectious morbidity or pregnancy latency. There was an increase in spontaneous labor in the group with more exams; this may be due to confounding by indication, as patients who are in prodromal labor are more likely to receive digital exams. These results suggest equipoise in exam type in the management of PPROM.

How changes in the mean latency, jitter amplitude, and jitter frequency impact target acquisition performance

Interactive technologies require the user to frequently generate purposeful movements, where actions are guided towards targets. While delays between the movement onset and the corresponding update within the virtual space have been shown to impair target acquisition, the relative contribution of the individual latency parameters remains unclear. This paper investigates how changes in latency, the moment-by-moment variability in the latency (jitter amplitude) and the rate of variability (jitter frequency), affect the speed and accuracy of target acquisition at different mean latencies. Experiment 1 explored changes in the mean latency and jitter amplitude. As the mean latency increased, we observed substantial impairments in completion time and accuracy, with increased variability in performance. There was also an interaction between the mean latency and jitter amplitude: although large jitter amplitudes caused a small completion time impairment, this effect decreased as the mean latency increased. Experiment 2 isolated the effect of the jitter by investigating changes in the jitter amplitude and jitter frequency at a fixed mean latency. Here, we observed completion time impairments from 67ms amplitude and accuracy impairments from 134ms amplitude. Like Experiment 1, the effect of the amplitude was small. Notably, we found no evidence that changes in the jitter frequency significantly influenced performance. Overall, increases in the mean latency contributed most to the impairment, disrupting acquisition speed and accuracy as it increased. Large jitter amplitudes also disrupted speed and accuracy, but this was a comparatively small effect that was mediated by the mean latency.

A common stay-on-goal mechanism in anterior cingulate cortex for information and effort choices.

Humans and non-humans alike often make choices to gain information, even when the information cannot be used to change the outcome. Prior research has shown the anterior cingulate cortex (ACC) is important for evaluating options involving reward-predictive information. Here we studied the role of ACC in information choices using optical inhibition to evaluate the contribution of this region during specific epochs of decision making. Rats could choose between an uninformative option followed by a cue that predicted reward 50% of the time vs. a fully informative option that signaled outcomes with certainty, but was rewarded only 20% of the time. Reward seeking during the informative S+ cue decreased following ACC inhibition, indicating a causal contribution of this region in supporting reward expectation to a cue signaling reward with certainty. Separately in a positive control experiment and in support of a known role for this region in sustaining high-effort behavior for preferred rewards, we observed reduced lever presses and lower breakpoints in effort choices following ACC inhibition. The lack of changes in reward latencies in both types of decisions indicate the motivational value of rewards remained intact, revealing instead a common role for ACC in maintaining persistence toward certain and valuable rewards.

Neuronal sequences in population bursts encode information in human cortex.

Neural coding has traditionally been examined through changes in firing rates and latencies in response to different stimuli1-5. However, populations of neurons can also exhibit transient bursts of spiking activity, wherein neurons fire in a specific temporal order or sequence6-8. The human brain may utilize these neuronal sequences within population bursts to efficiently represent information9-12, thereby complementing the well-known neural code based on spike rate or latency. Here we examined this possibility by recording the spiking activity of populations of single units in the human anterior temporal lobe as eight participants performed a visual categorization task. We find that population spiking activity organizes into bursts during the task. The temporal order of spiking across the activated units within each burst varies across stimulus categories, creating unique stereotypical sequences for individual categories as well as for individual exemplars within a category. The information conveyed by the temporal order of spiking activity is separable from and complements the information conveyed by the units' spike rates or latencies following stimulus onset. Collectively, our data provide evidence that the human brain contains a complementary code based on the neuronal sequence within bursts of population spiking to represent information.

Effect of pre-session discrimination training on performance in a judgement bias test in dogs

Spatial judgement bias tests (JBTs) can involve teaching animals that a bowl provides a reward in one location but does not in another. The animal is then presented with the bowl placed between the rewarded and the unrewarded locations (i.e., ambiguous locations) and their latency to approach reflects expectation of reward or ‘optimism’. Some suggest that greater ‘optimism’ indicates better welfare. Performance in JBTs, however, may also indicate a learning history independently from welfare determinants. We hypothesized that dogs’ ‘optimism’ in a follow-up JBT may be impacted by a learning treatment involving additional trials of a different discrimination task. Once enrolled, companion dogs (n = 16) were required to complete three study phases: (1) a pre-treatment JBT, (2) a learning treatment, and (3) a post-treatment JBT. During the JBTs, dogs were presented with five locations: one rewarded, one unrewarded, and three ambiguous (all unrewarded). Dogs were randomly assigned to a trial-based learning task—a nose-touch to the palm of the hand. In the Experimental discrimination treatment phase (n = 8), dogs were presented with two hands in each trial and only rewarded for touching one specific hand. In the Control treatment phase (n = 8), dogs were presented with one hand per trial in alternating sequence and were yoked to dogs in the Experimental group to receive the same number of rewarded and unrewarded trials (to control for possible frustration). Using a repeated measures mixed model with JBT repeated within dog, we found no difference in the change in approach latency to the ambiguous locations between the dogs across treatments. ‘Optimism’ as measured in this JBT was not altered by the additional discrimination trials used in our study.

Fronto-Central Changes in Multiple Frequency Bands in Active Tactile Width Discrimination Task.

The neural basis of tactile processing in humans has been extensively studied; however, the neurophysiological basis of human width discrimination remains relatively unexplored. In particular, the changes that occur in neural networks underlying active tactile width discrimination learning have yet to be described. Here, it is hypothesized that subjects learning to perform the active version of the width discrimination task would present changes in behavioral data and in the neurophysiological activity, specifically in networks of electrodes relevant for tactile and motor processing. The specific hypotheses tested here were that the performance and response latency of subjects would change between the first and the second blocks; the power of the different frequency bands would change between the first and the second blocks; electrode F4 would encode task performance and response latency through changes in the power of the delta, theta, alpha, beta, and low-gamma frequency bands; the relative power in the alpha and beta frequency bands in electrodes C3 and C4 (Interhemispheric Spectral Difference-ISD) would change because of learning between the first and the second blocks. To test this hypothesis, we recorded and analyzed electroencephalographic (EEG) activity while subjects performed a session where they were tested twice (i.e., two different blocks) in an active tactile width discrimination task using their right index finger. Subjects (n = 18) presented high performances (high discrimination accuracy) already in their first block, and therefore no significant improvements were found in the second block. Meanwhile, a reduction in response latency was observed between the two blocks. EEG recordings revealed an increase in power for the low-gamma frequency band (30-45 Hz) for electrodes F3 and C3 from the first to the second block. This change was correlated with neither performance nor latency. Analysis of the neural activity in electrode F4 revealed that the beta frequency band encoded the subjects' performance. Meanwhile, the delta frequency band in the same electrode revealed a complex pattern where blocks appeared clustered in two different patterns: an Upper Pattern (UP), where power and latency were highly correlated (Rho = 0.950), and a sparser and more uncorrelated Lower Pattern (LP). Blocks belonging to the UP or LP patterns did not differ in performance and were not specific to the first or the second block. However, blocks belonging to the LP presented an increase in response latency, increased variability in performance, and an increased ISD in alpha and beta frequency bands for the pair of electrodes C3-C4, suggesting that the LP may reflect a state related to increased cognitive load or task difficulty. These results suggest that changes in performance and latency in an active tactile width discrimination task are encoded in the delta, alpha, beta, and low-gamma frequency bands in a fronto-central network. The main contribution of this study is therefore related to the description of neural dynamics in frontal and central networks involved in the learning process of active tactile width discrimination.

Combined-electrical optogenetic stimulation but not channelrhodopsin kinetics improves the fidelity of high rate stimulation in the auditory pathway in mice

Novel stimulation methods are needed to overcome the limitations of contemporary cochlear implants. Optogenetics is a technique that confers light sensitivity to neurons via the genetic introduction of light-sensitive ion channels. By controlling neural activity with light, auditory neurons can be activated with higher spatial precision. Understanding the behaviour of opsins at high stimulation rates is an important step towards their translation. To elucidate this, we compared the temporal characteristics of auditory nerve and inferior colliculus responses to optogenetic, electrical, and combined optogenetic-electrical stimulation in virally transduced mice expressing one of two channelrhodopsins, ChR2-H134R or ChIEF, at stimulation rates up to 400 pulses per second (pps). At 100 pps, optogenetic responses in ChIEF mice demonstrated higher fidelity, less change in latency, and greater response stability compared to responses in ChR2-H134R mice, but not at higher rates. Combined stimulation improved the response characteristics in both cohorts at 400 pps, although there was no consistent facilitation of electrical responses. Despite these results, day-long stimulation (up to 13 h) led to severe and non-recoverable deterioration of the optogenetic responses. The results of this study have significant implications for the translation of optogenetic-only and combined stimulation techniques for hearing loss.

Fluctuations in resting motor threshold during electroconvulsive and magnetic seizure therapy

Objectives Magnetic seizure therapy (MST) is more benign than electroconvulsive therapy (ECT) in terms of cognitive impairment. However, whether these two ‘artificial seizures’ facilitate the central motor neural pathway and the motor cortical effects have not been investigated. The study aimed to compare the effects of ECT and MST on motor-evoked potential (MEP) in patients with mental disorders. Methods Forty-nine patients with mental disorders (major depressive disorder, bipolar disorder type II and schizophrenia [SCZ]) received 6 treatment sessions of vertex MST versus 6 bifrontal ECT treatments in a nonrandomized comparative clinical design. Data on the duration of motor seizures were collected for each treatment. MEP latency and the resting motor threshold (rMT) were measured at baseline and after every two treatments. Comparisons were performed between or within the groups. Results Seizure durations were significantly longer in the ECT group compared to the MST group across multiple sessions. Both MST and ECT demonstrated a significant reduction in rMT in the left and right hemispheres after the fourth (T3) and sixth treatments (T4) compared to baseline (T1). However, there were no significant changes in MEP latency within or between the groups throughout the treatment sessions. The only difference was that the rMT in the left cerebral hemisphere was significantly lower after T4 than after the second treatment (T2). There was no difference in rMT between the ECT and MST groups. Conclusions Both ECT and MST facilitate the central motor pathway, with a shared mechanism of increased motor cortex excitability.

Comparison of Regression Methods to Predict the First Spike Latency in Response to an External Stimulus in Intracellular Recordings for Cerebellar Cells.

The significance of intracellular recording in neurophysiology is emphasized in this article, with considering the functions of neurons, particularly the role of first spike latency in response to external stimuli. The study employs advanced machine learning techniques to predict first spike latency from whole cell patch recording data. Experiments were conducted on Control (Salin) and Experiment (Harmaline) groups, generating a dataset for developing predictive models. Because the dataset has a limited number of samples, we utilized models that are effective with small datasets. Among different groups of regression models (linear, ensemble, and tree models), the ensemble models, specifically the LGB method, can achieve better performance. The results demonstrate accurate prediction of first spike latency, with an average mean squared error of 0.0002 and mean absolute error of 0.01 in 10-fold cross-validation. The research suggests the potential of machine learning in forecasting the first spike latency, allowing reliable estimation without the need for extensive animal testing. This intelligent predictive system facilitates efficient analysis of first spike latency changes in both healthy and unhealthy brain cells, streamlining experimentation and providing more detailed insights into the captured signals.

White matter and latency of visual evoked potentials during maturation: A miniature pig model of adolescent development

BackgroundContinuous myelination of cerebral white matter (WM) during adolescence overlaps with the formation of higher cognitive skills and the onset of many neuropsychiatric disorders. We developed a miniature-pig model of adolescent brain development for neuroimaging and neurophysiological assessment during this critical period. Minipigs have gyroencephalic brains with a large cerebral WM compartment and a well-defined adolescence period. MethodsEight Sinclair™ minipigs (Sus scrofa domestica) were evaluated four times during weeks 14–28 (40, 28 and 28 days apart) of adolescence using monocular visual stimulation (1 Hz)-evoked potentials and diffusion MRI (dMRI) of WM. The latency for the pre-positive 30 ms (PP30), positive 30 ms (P30) and negative 50 ms (N50) components of the flash visual evoked potentials (fVEPs) and their interhemispheric latency (IL) were recorded in the frontal, central and occipital areas during ten 60-second stimulations for each eye. The dMRI imaging protocol consisted of fifteen b-shells (b = 0–3500 s/mm2) with 32 directions/shell, providing measurements that included fractional anisotropy (FA), radial kurtosis, kurtosis anisotropy (KA), axonal water fraction (AWF), and the permeability-diffusivity index (PDI). ResultsSignificant reductions (p < 0.05) in the latency and IL of fVEP measurements paralleled significant rises in FA, KA, AWF and PDI over the same period. The longitudinal latency changes in fVEPs were primarily associated with whole-brain changes in diffusion parameters, while fVEP IL changes were related to maturation of the corpus callosum. ConclusionsGood agreement between reduction in the latency of fVEPs and maturation of cerebral WM was interpreted as evidence for ongoing myelination and confirmation of the minipig as a viable research platform. Adolescent development in minipigs can be studied using human neuroimaging and neurophysiological protocols and followed up with more invasive assays to investigate key neurodevelopmental hypotheses in psychiatry.

Association of the Achondroplasia Foramen Magnum Score and intraoperative neuromonitoring

IntroductionForamen magnum stenosis in achondroplasia carries a risk of sudden death. A proportion of these patients benefit from foramen magnum decompression (FMD). The Achondroplasia Foramen Magnum Score (AFMS) was developed...

Assessment of Upper Limb Nerves in Coronary Artery Disease Patients Undergoing Coronary Artery Bypass Graft.

Background Many patients experience pain in their upper limbs following surgical procedures involving median sternotomy, particularly those undergoing coronary artery bypass grafting (CABG). This type of pain, commonly reported by CABG patients, is often overlooked in hospital settings. Our study aims to address this issue by utilizing electrodiagnostic studies to understand this postoperative discomfort better. Objectives Cardiovascular procedures are standard and are trending toward endovascular interventions. Through this study, we aim to assess the occurrence of neurological issues in the upper limbs after CABGby comparing patients' preoperative and postoperative electrophysiological studies of the upper limb nerves. Materials and methods A prospective study was performed on 32 coronary artery disease (CAD) patients undergoing CABG to determine the effects of surgery on the upper limb nerves (median and ulnar nerves). We performed nerve conduction studies (NCS) and analyzed different parameters of both median and ulnar nerves pre and post-surgery. Results A change was noted in different NCS parameters of the median and ulnar nerves when we comparedthe pre and post-surgical values. The meanlatency of the median nerve sensory increased from a minimum of 3.01 millisecondsat the preoperative level to a maximum of 3.60 milliseconds when assessedtwo weeks post-surgery. The mean amplitude decreased from 16.49 microvolts to a minimum of 12.30 microvolts when assessed two weeks post-surgery. The meanvelocity decreased from 55.83 m/s at the preoperative value to a minimum of 45.03 m/sat the two weeks post-surgery assessment. The ulnar nerve also underwent similar changes. Conclusion The observed changes in latency, amplitude, and velocity might be attributed to various factors, including surgical trauma, inflammation, or alterations in the physiological state post-surgery. The sternotomy technique and the position and extent of opening the sternal retractor determine the prevalence of complications by causing injury to the medial and lateral cords of the brachial plexusafter CABG. Careful preoperative and postoperative assessments of patients may aid in preventing, minimizing, and treating these often undiagnosed complications.