Latency Of Wave Research Articles

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.

The potential role of the SIRT1‐Nrf2 signaling pathway in alleviating hidden hearing loss via antioxidant stress

AbstractHidden hearing loss (HHL) is characterized by normal audiometric thresholds but impaired auditory function, particularly in noisy environments. In vivo, we employed auditory brainstem response (ABR) testing and ribbon synapses counting to assess changes in mouse hearing function, and observed the morphology of hair cells through scanning electron microscopy. SRT1720 was administered to the cochlea via round window injection. In vitro, western blot analysis and RT‐qPCR were used, and Lenti‐shNrf2 was used to knockdown Nrf2 expression. In addition, various oxidative stress indicators were detected by immunofluorescence, kit‐based assays, and flow cytometry. ABR measurement of HHL mouse showed a significant increase in hearing threshold, as well as a decrease and delay in the I wave amplitude and latency on the first day after noise exposure. Histological observation showed a significant loss of ribbon synapses and stereocilia lodging. HHL mice exhibited oxidative stress, which was reduced by pretreatment with SRT1720. Additionally, SRT1720 could reduce hydrogen peroxide‐induced oxidative stress in HEI‐OC1 cells through activating the SIRT1/Nrf2 pathway. Subsequent experiments with Nrf2 knockdown confirmed the importance of this pathway. findings highlight oxidative stress as the primary contributor to HHL, with the SIRT1/Nrf2 signaling pathway emerging as a promising therapeutic target for alleviating HHL.

Maturational delay in the brainstem auditory pathway of very preterm babies with apnoea

AimsTo assess the maturational status of the brainstem auditory pathway in babies with apnoea of prematurity (AOP) at 33–34 weeks of postmenstrual age (PMA), an important time landmark at which AOP is resolved in most cases. Study designCompare brainstem auditory maturation between very preterm babies with AOP and those without AOP (non-AOP) at the same PMA 33–34 weeks to define differences. ResultsThe AOP group showed significantly longer latencies of waves III and V latency than the non-AOP group (p < 0.05 and 0.01). The I-V interval in the AOP group was significantly longer than in the non-AOP group (p < 0.001). The same was true for the I-III and III-V intervals (p < 0.001 and 0.05). Wave III amplitude was significantly smaller (p < 0.05), and wave V amplitude was moderately smaller than in the non-AOP. At PMA 33 weeks, waves III and V latencies and all intervals in the AOP group were significantly longer than in the non-AOP group (p < 0.05–0.001). At PMA 34 weeks, these wave latencies and intervals in the AOP group were still significantly longer than in the non-AOP group (p < 0.05–0.01). Wave III amplitude in the AOP group was significantly smaller at both PMA 33 and 34 weeks (p < 0.05 and 0.05). ConclusionsBrainstem auditory maturation in AOP babies is delayed at PMA 33 weeks, and remains delayed at PMA 34 weeks. These findings highlight the importance of monitoring and adequate intervention strategies during PMA 33–34 weeks in AOP babies.

Auditory evoked brainstem responses and medial olivocochlear efferent system in migraine patients with phonophobia

ABSTRACT Objective This study aims to investigate Auditory Evoked Brainstem Responses (ABR) and Distortion Product Otoacoustic Emission (DPOAE) suppression in migraine patients with and without phonophobia. Methods Thirty-two migraine patients with normal hearing and 30 healthy individuals were included in the study. Migraine characteristics and phonophobia status of migraine patients were noted. The patients were divided into two groups according to their phonophobia status. All participants underwent ABR, DPOAE and DPOAE suppression. Results Migraine patients had less DPOAE suppression (1481 and 2222 hz) and shorter ABR wave latencies compared to the control group (p < 0.05). Twelve (37.5%) of the migraine patients did not have phonophobia, and 20 (62.5%) had phonophobia. Phonophobia was not found to affect DPOAE suppression (p > 0.05). However, ABR wave I and V latencies in migraine patients with phonophobia were shorter than in healthy individuals (p < 0.05). Conclusion There are changes in the auditory evoked brainstem responses and medial olivocochlear efferent system of migraine patients. While phonophobia in migraine patients does not affect the medial olivocochlear efferent system, it may affect auditory evoked brainstem responses.

Electroacupuncture improves V1 cortex synaptic plasticity via the CREB/BDNF/TrkB pathway in juvenile rats with monocular deprivation

The present study aims to investigate the impact of the CREB/BDNF/TrkB signaling pathway on synaptic plasticity in the visual cortex of juvenile amblyopic rats that have undergone monocular deprivation (MD). This study involved sixty 2-week-old Sprague-Dawley (SD) juvenile rats, which were not specified by gender. In the first part of the study, 24 rats were randomized into control and MD groups; In the second part, 36 rats were randomized into MD, electroacupuncture (EA) and EA + CREB antagonist (666–15) groups. The MD model was established using the monocular suture method. 14 d after monocular suture, EA treatment was started for 30 min daily, at a frequency of 2–10 Hz and an intensity of 1 mA, for 2 weeks. According to the results from part 1, the P100 wave latency in the MD group was prolonged, and its amplitude was lower compared to the control group. Additionally, the neuron number in the V1 cortex of the MD group decreased, along with reduced expression levels of CREB, BDNF, p-TrkB, and the key plasticity proteins PSD95 and SYN. In part 2, EA treatment significantly increased the electrophysiological activity of neurons in V1 cortex, shortened the latency of P100 peaks to varying degrees, increased the amplitude significantly, and restored the morphology and structure of neurons to normal levels; The expression of synaptic proteins PSD95 and SYN, as well as the expression of signaling molecules CREB, BDNF, and p-TrkB proteins were increased. However, the effects of EA were reversed when the specific CREB inhibitor 666–16 was administered. These data indicate that EA enhances the expression of V1 cortical synaptic plasticity-related proteins by regulating the expression of CREB/BDNF/TrkB signaling pathway, thereby enhancing V1 neural synaptic plasticity and reversing the effects of MD on visual acuity.

Brainstem auditory evoked responses: Objective hearing threshold assessment in Holstein cows.

Animal audiology utilizes brainstem auditory evoked responses (BAER) as a non-invasive tool to assess hearing in animals, including Holstein dairy cows. Understanding cows' auditory capabilities is critical for their welfare, especially given their exposure to farm noise. This study provides preliminary normative BAER data for Holstein cows by focusing on absolute and interpeak wave latencies. The objective is to assess the impact of farm noise and expand audiologists' practice scope. Ten Holstein cows were tested using monoaural broadband click stimuli with contralateral masking. Earphones with foam ear tips were used to minimize environmental noise interference. The BAER responses were recorded via subdermal needle electrodes placed at standardized locations on the cows' heads. The data were analysed using descriptive statistics to determine auditory thresholds and wave latencies. The cows exhibited auditory thresholds at 90 dB SPL (55 dB nHL). Detailed wave and interpeak latencies were recorded at intensities from 85 to 105 dB SPL. At 90 dB SPL, the average latency for wave V was 5.17 ms, marking the auditory threshold for Holstein cows. These findings provide key insights into the auditory sensitivity of Holstein cows, highlighting BAER's potential for monitoring auditory health and evaluating the effects of noise pollution on animal welfare. This research underscores the value of integrating animal audiology into the audiologist's scope, ultimately enhancing both animal welfare and farming sustainability.Contribution:This study adds to the limited literature on farm animal auditory health and suggests strategies to improve welfare through better auditory management.

Comparative exploration on EEG signal filtering using window control methods

Electroencephalography (EEG) is used to monitor brain activity. The brain signals consist of different frequency band signals delta, theta, alpha, beta, and gamma waves. The signals are affected by external noise which reduces the quality of the EEG signal due to which it becomes difficult to do further processing of EEG signals like feature extraction or extraction of meaningful features from EEG signal. Therefore, it becomes important to filter the noise from the EEG signal before feature extraction or classification of the EEG signal. The research article presents an overview of different types of windowing filter techniques like Rectangular, Bartlett, Hamming, Hanning, and Kaiser windows applied for finite impulse response (FIR) behavior which is used for EEG signal processing for different brain waves processed in different frequency bands. The comparative analysis is carried out in terms of the response time of brain frequency bands for different windowing filter techniques using the MATLAB 2023 signal processing simulation tool. The novelty of the work lies in estimating minimum latency and appropriate filter selection for various typical EEG waves, since the EEG signals are pre-supposed in the hardware chip design, noise elimination is the first step in high-performance computing applications. The Bartlett window band stop has an optimal response time of 12.666 s for delta waves, a highpass filter with a response time of 16.187 s for theta waves, a bandpass with a response time of 13.122 s for alpha waves, a highpass filter with a response time of 17.866 s for beta waves, and a highpass filter with a response time of 13.797 s for gamma waves. The Barlett window FIR filter is well-suited for EEG applications.

Evaluation of the clinical effect of 4D digital strabismus and amblyopia visual function correction system combined with traditional comprehensive treatment methods on anisometropic amblyopia

PurposeThe objective of this study was to evaluate the clinical efficacy of a 4D digital strabismus and amblyopia visual function correction system (4D-DSAAVFCS) in combination with conventional modalities compared with conventional modalities alone in children with anisometropic amblyopia.MethodsThis nonrandomized controlled study collected data on best-corrected visual acuity (BCVA), simultaneous vision, fusion vision, near stereoscopic vision, the amplitude of P100 wave (graphic evoked visual potentials), and the latency of P100 wave from both eyes at the beginning of the treatment and one year later. The Mann‒Whitney U test was used to compare BCVA contrasts in different subgroups, and the independent samples t test was used to compare the amplitude and latency of P100 wave contrasts in different subgroups. The basic cure rate, simultaneous vision recovery rate, fusion vision recovery rate, and near stereoscopic vision recovery rate contrasts in different subgroups were compared via the chi-square test.ResultsThis study included 393 children (217 boys and 176 girls) aged 3 to 12 years with anisometropic amblyopia who were treated at the Aier Eye Hospital of Wuhan University from January 2020 to December 2022. The children were divided into two groups, the 4D group (263 cases) and the traditional group (130 cases), on the basis of the treatment modality. The children in the traditional group received treatment through the conventional method of occlusion and regular training. Meanwhile, the children in the 4D group received treatment through the traditional method and the 4D-DSAAVFCS. The 4D group was divided into two age groups: 3 ~ 6 years (161 cases) and 6 ~ 12 years (102 cases). The basic cure rate of the 4D group was significantly better than that of the traditional group (χ2 = 4.318, P < 0.05). There were no statistically significant differences in the BCVA, the latency of P100 wave, or the amplitude of P100 wave between the 4D group and the traditional group before treatment (U=-0.117, t=-0.05, all P > 0.05 ). After one year of treatment, a statistically significant difference was observed between the 4D group and the conventional group in terms of BCVA, the latency of P100 wave, and the amplitude of P100 wave (U=-1.243, t=-0.853, t=-1.546, all P < 0.05). These results suggest that the therapeutic effect was greater in the 4D group than in the conventional group. The recovery rates of simultaneous vision, convergent fusion, divergent fusion, and near stereoscopic vision were significantly greater in the 4D group than in the conventional group (χ2 = 4.344, 4.726, 5.123, and 2.036, respectively; all P < 0.05). Additionally, the basic cure rate of children aged 3 ~ 6 years in the 4D group was significantly greater than that of children aged 6 ~ 12 years (χ2 = 2.365, P < 0.05). In this study, BCVA was significantly lower in the 3 ~ 6-year-old group than in the 6 ~ 12-year-old group (U = -1.267, P < 0.05). Similarly, the amplitude of P100 wave was also significantly greater in the 3 ~ 6-year-old group than in the 6 ~ 12-year-old group (t = -1877, P < 0.05). The latency of P100 wave was lower in the 3 ~ 6-year-old group than in the 6 ~ 12-year-old group (t=-0.998, P < 0.05). Additionally, the recovery rate of near stereoscopic vision was significantly greater in the 3 ~ 6-year-old group than in the 6 ~ 12-year-old group (χ2 = 4.534, P < 0.05).ConclusionThe combination of the traditional method with the 4D-DSAAVFCS was more effective than the traditional method alone in treating amblyopic children. This approach was particularly helpful in improving the visual acuity of the children and restoring their optic nerve conduction function, simultaneous vision, fusion vision, and near stereoscopic vision. The combination of the traditional method and the 4D-DSAAVFCS is more effective for younger children.

Effects of Apelin-13 on auditory system in STZ-induced diabetic rats

AimDamage to the auditory pathways is one of the complications of diabetes. The aim of this study was to investigate the potential therapeutic effects of apelin-13 in the auditory pathways of rats with experimentally induced diabetes by examining its effect on auditory brainstem responses, cochlear oxidative stress and inflammatory cytokines. MethodsThirty-two male Wistar albino rats were divided into four groups: sham control, diabetes, apelin and diabetes + apelin. A single dose of 45 mg/kg streptozotocin (STZ) was administered to induce diabetes. The apelin group received 50 µg/kg apelin-13 for seven days intraperitoneally (ip). At the end of the apelin and STZ applications auditory brainstem responses (ABR) was recorded. At the end of the experiment, cochlea was removed and biochemical analyzes were performed. ResultsIn ABR recordings, the latencies of wave V in diabetic group were observed to be longer than those of the control, with the apelin treatment exhibiting a partial reversal of this situation, particularly at specific frequencies and intensity levels. Apelin treatment leads to a significant increase in total antioxidant status (TAS) and a reduction in total oxidant status (TOS) and oxidative stress index (OSI) in cochlea compared to diabetic groups. The levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin 1-beta (IL-1 beta) in cochlear tissue were found to be significantly reduced in the apelin-treated group compared to the diabetic group. ConclusionApelin-13 may have a protective effect on the auditory system and may be proposed as a potential new therapeutic strategy for the management diabetic auditory impairment.

Noise-induced cochlear synaptopathy in C57BL/6 N mice as a function of trauma strength: ribbons are more vulnerable than postsynapses.

Noise-induced cochlear synaptopathy is characterized by irreversible loss of synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) despite normal hearing thresholds. We analyzed hearing performance and cochlear structure in C57BL/6 N mice exposed to 100, 106, or 112 dB SPL broadband noise (8-16 kHz) for 2 h. Auditory brainstem responses (ABRs) were assessed before, directly after, and up to 28 days post-trauma. Finally, the number, size, and pairing of IHC presynaptic (CtBP2-positive) ribbons and postsynaptic AMPA receptor scaffold (Homer1-positive) clusters were analyzed along the cochlea. Four weeks after the 100 dB SPL trauma, a permanent threshold shift (PTS) was observed at 45 kHz, which after the higher traumata extended toward middle to low frequencies. Loss in ABR wave I amplitudes scaled with trauma strength indicating loss of functional IHC synaptic connections. Latencies of wave I mostly increased with trauma strength. No trauma-related OHC loss was found. The number of synaptic pairs was reduced in the midbasal and basal cochlear region in all trauma conditions, with ribbon loss amounting up to 46% of control. Ribbons surviving the trauma were paired, whereas 4-6 unpaired postsynapses/IHC were found in the medial, midbasal, and basal regions irrespective of trauma strength, contrasting findings in CBA/CaJ mice. Our data confirm the susceptibility of ribbon synapses and ABR wave I amplitudes to a noise trauma of 100 dB SPL or larger. Notably, peripheral dendrites bearing IHC postsynapses were less vulnerable than presynaptic ribbons in C57BL/6 N mice.

Maternal oral probiotic use is associated with decreased breastmilk inflammatory markers, infant fecal microbiome variation, and altered recognition memory responses in infants-a pilot observational study.

Early life gut microbiomes are important for brain and immune system development in animal models. Probiotic use has been proposed as a strategy to promote health via modulation of microbiomes. In this observational study, we explore if early life exposure to probiotics via the mother during pregnancy and lactation, is associated with decreased inflammation in breastmilk, maternal and infant microbiome variation, and altered infant neurodevelopmental features. Exclusively breastfeeding mother-infant dyads were recruited as part of the "Mothers and Infants Linked for Healthy Growth (MILk) Study." Probiotic comparison groups were defined by exposure to maternal probiotics (NO/YES) and by timing of probiotic exposure (prenatal, postnatal, total). C-reactive protein (CRP) and IL-6 levels were determined in breastmilk by immunoassays, and microbiomes were characterized from 1-month milk and from 1- and 6-month infant feces by 16S rDNA sequencing. Infant brain function was profiled via electroencephalogram (EEG); we assessed recognition memory using event-related potential (ERP) responses to familiar and novel auditory (1 month) and visual (6 months) stimuli. Statistical comparisons of study outcomes between probiotic groups were performed using permutational analysis of variance (PERMANOVA) (microbiome) and linear models (all other study outcomes), including relevant covariables as indicated. We observed associations between probiotic exposure and lower breastmilk CRP and IL-6 levels, and infant gut microbiome variation at 1- and 6-months of age (including higher abundances of Bifidobacteria and Lactobacillus). In addition, maternal probiotic exposure was associated with differences in infant ERP features at 6-months of age. Specifically, infants who were exposed to postnatal maternal probiotics (between the 1- and 6-month study visits) via breastfeeding/breastmilk, had larger differential responses between familiar and novel visual stimuli with respect to the late slow wave component of the EEG, which may indicate greater memory updating potential. The milk of mothers of this subgroup of infants had lower IL-6 levels and infants had different 6-month fecal microbiomes as compared to those in the "NO" maternal probiotics group. These results support continued research into "Microbiota-Gut-Brain" connections during early life and the role of pre- and postnatal probiotics in mothers to promote healthy microbiome-associated outcomes in infants.

Characteristics of Speech Auditory Brainstem Response in Preschool Children With Attention-Deficit/Hyperactivity Disorder.

This study aimed to investigate the characteristics of auditory processing (AP) in preschool children with attention-deficit/hyperactivity disorder (ADHD) using the speech auditory brainstem response (speech-ABR), which provides insights into the AP of speech signals in the central auditory nervous system (CANS). A total of 84 preschool children diagnosed with ADHD, aged 4-6 years, were matched with 84 typically developing (TD) children based on gender and age. All children underwent speech-ABR testing, cognitive assessment using the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition or the Wechsler Intelligence Scale for Children-Fourth Edition, and a continuous performance test. Children with ADHD exhibited significantly longer latencies of speech-ABR waveforms V, A, and D compared to TD children. Multiple linear regression analysis showed that the latencies of speech-ABR waves V, A, and D were affected by the presence of ADHD, but not by the full-scale intelligence quotient. This study revealed that preschool children with ADHD exhibited abnormal AP of speech signals in their CANS. The findings suggest that speech-ABR can be utilized as a reliable measure to evaluate AP ability in this population, as it remains unaffected by cognitive or attentional factors. The transient response (V, A) of speech-ABR was found to be a significant predictor of ADHD in a clinical setting. Early assessment of AP abnormalities via speech-ABR is recommended in preschool-age children to develop targeted interventions for ADHD. https://doi.org/10.23641/asha.26376502.

Factors influencing auditory brainstem response changes in infants

BackgroundTo elucidate the factors influencing auditory brainstem response (ABR) threshold improvement in infants. MethodsThis retrospective study included 626 infants who underwent ABR at the our Health and Medical Center between 2016 and 2020. Preliminary assessment indicated that 352 infants had an ABR threshold ≥40 dBnHL in both ears. A second ABR examination was conducted 5 months after delivery. The participants were divided into the improved (improvement ≥20 dBnHL) and unchanged (improvement <20 dBnHL) groups. The associations between risk factors were evaluated. Furthermore, we measured and compared the latencies of waves I, III, and V between participants with normal hearing and those in the improved and unchanged groups. ResultsThe improved and unchanged groups consisted of 185 and 167 participants, respectively. ABR deterioration occurred in one infant with unilateral congenital cytomegalovirus-associated hearing loss. Binary logistic regression analysis revealed that the presence of otitis media with effusion and Down syndrome were factors contributing to ABR threshold improvement. In the ABR waveform analysis, patients in the improved group who had otitis media with effusion exhibited prolonged latencies of waves I, III, and V. Conversely, patients in the unchanged group who had Down syndrome showed shortened I–V interval. ConclusionsHalf of the infants tested the second time showed improvement in ABR threshold. Children with congenital syndromes (such as Down syndrome) or otitis media with effusion should undergo a second ABR examination or other auditory assessments to ensure an accurate diagnosis of hearing loss.

The Neural and Computational Architecture of Feedback Dynamics in Mouse Cortex during Stimulus Report.

Conscious reportability of visual input is associated with a bimodal neural response in the primary visual cortex (V1): an early-latency response coupled to stimulus features and a late-latency response coupled to stimulus report or detection. This late wave of activity, central to major theories of consciousness, is thought to be driven by the prefrontal cortex (PFC), responsible for "igniting" it. Here we analyzed two electrophysiological studies in mice performing different stimulus detection tasks and characterized neural activity profiles in three key cortical regions: V1, posterior parietal cortex (PPC), and PFC. We then developed a minimal network model, constrained by known connectivity between these regions, reproducing the spatiotemporal propagation of visual- and report-related activity. Remarkably, while PFC was indeed necessary to generate report-related activity in V1, this occurred only through the mediation of PPC. PPC, and not PFC, had the final veto in enabling the report-related late wave of V1 activity.

Impaired cognitive flexibility in major depressive disorder: Evidences from spatial-temporal ERPs analysis

BackgroundMajor Depressive Disorder (MDD) may exhibit impairments in cognitive flexibility. This study investigated whether the cognitive flexibility deficits in MDD are evident across general stimuli or specific to emotional stimuli, while exploring the underlying neuropsychological mechanism. MethodsA total of 41 MDD patients and 42 healthy controls (HCs) were recruited. Event-related potentials (ERPs) were recorded when participants performed a non-emotional and an emotional task switching paradigm (N-ETSP and ETSP), both of which assessed cognitive flexibility. Microstate and source localization analysis were applied to reflect brain activity among different brain areas during task switching. ResultsIn the N-ETSP, MDD group showed larger P3 difference wave (Pd3) amplitudes and longer P2 difference wave (Pd2) latencies. In the ETSP, MDD group displayed smaller N2 difference wave (Nd2) amplitudes and larger Pd3 amplitudes. The comparison of sLORETA images of emotional switch task and emotional repeat task showed that MDD group had increased activation in the precentral gyrus in microstate2 of the P2 time window and had reduced activation in the middle occipital gyrus in microstate3 of the N2 time window. LimitationsThe cross-sectional design failed to capture dynamic changes in cognitive flexibility in MDD. ConclusionsMDD demonstrated impaired cognitive flexibility respond to both non-emotional and emotional stimuli, with greater impairment for negative emotional stimuli. These deficits are evident in abnormal ERPs component during the early attention stage and the later task preparation stage. Furthermore, abnormal emotional switching cost in MDD appears to be related to early abnormal perceptual control in the parietal-occipital cortex.

Effect of the Heaviness of Smoking Index (HSI) and Duration of Smoking on Central Neural Processing Using Brainstem Auditory Evoked Responses (BAERs).

Purpose of study The goal of this research was to find the correlation of nicotine dependence and duration of smoking with the status of central neuronal processing in chronic smokers. Our primary objective was to record brainstem auditory evoked responses (BAERs) in chronic smokers and further find their correlation to the Heaviness of Smoking Index (HSI) scores and years of non-abstained smoking of the subjects. We postulated that smoking leads to myelination abnormalities which in turn causes decreased impulse conduction velocity. Methods After obtaining informed consent, we conducted BAER on 60 male smokers who were further classified into groups based on their HSI scores (low, moderate, and high nicotine dependency) and 20 age-matched, non-smoking males. The obtained data was examined using the two-way ANOVA test and the Kruskal-Wallis test. Pearson's coefficient of correlationand the median (as a measure of central tendency) were calculated. Results We observed a non-significant negative correlation between wave I BAER latency and the degree of nicotine dependence. Wave II showed minimal correlation, whereas a positive correlation was seen in waves III, IV, and V. Interpeak latencies (IPL) I-III and III-V showed a non-significant positive correlation with the HSI score, whereas IPL I-V showed a significant positive correlation with the same. When correlated with the duration of smoking (years), the latencies (msec) of BAER waves I-V showed a pattern of progressively decreasing negative correlation, out of which waves I, II, and III were significantly affected. The IPL (msec) of waves I-III was non-significantly, yet positively, correlated, while the IPL of waves I-V and III-V showed a significant positive correlation to the duration of smoking. Conclusions The degree of nicotine dependence and duration of tobacco smoking progressively affected the latencies of BAER waves at the pontomedullary level of the brainstem. This indicates slower central neuronal processing at this level and an increased central transmission time, the extent of which is directly dependent on the extent of tobacco smoking. This is attributed to the myelination defects caused by direct and indirect effects of the toxic metabolites of tobacco smoke, chronic hypoxia, hypercapnia, and respiratory acidosis.

Audiological profile of patients with type 2 diabetes mellitus.

South Africa shows a high prevalence of type 2 diabetes with reported association with auditory dysfunction. To describe the audiological profile of adults with this metabolic condition. Employing a descriptive research design, 35 individuals with type 2 diabetes, selected through purposive sampling, underwent a basic audiological assessment in addition to extended high-frequency (EHF) audiometry, distortion product otoacoustic emissions (DPOAE) testing and neurological auditory brainstem response (ABR) test. This study revealed a 31.4% prevalence of hearing loss with 81.8% being sensorineural in nature. Poor hearing thresholds were observed at 16 kHz (n= 19; 54.3%), 18 kHz (n= 24; 68.6%) and 20 kHz (n= 30; 85.7%) in the right ear and at 16 kHz (n= 20; 57.1%), 18 kHz (n= 24; 68.6%) and 20 kHz (n= 30; 85.7%) in the left ear. Absent DPOAEs were observed at 6 kHz (n= 20; 51.7%) and 8 kHz (n= 24; 68.6%) in the right ear and at 6 kHz (n= 17; 48.6%) and 8 kHz (n= 29; 82.9%) in the left ear, possibly indicating that type 2 diabetes specifically targets higher frequency hearing. The ABR results revealed a delayed absolute latency of wave III bilaterally (right ear -69%; left ear - 51%), suggesting an impact of this metabolic disease on retro-cochlear pathways. Hearing loss should be recognised as a comorbidity accompanying type 2 diabetes, which indicates the need for routine comprehensive audiological assessments to facilitate early detection and intervention.Contribution:The present findings have implications for audiology clinical protocols; diabetes related health policies and patient education.

The effectiveness of curcumin as a safe agent on hearing threshold improvement in patients with chronic kidney disease: a double-blind, placebo-controlled trial

Hearing impairment in patients with chronic kidney disease (CKD), can affect the quality of life. At present, hearing dysfunction does not have an approved pharmacologic therapy. This study aimed to investigate the protective effects and possible mechanisms of curcumin as a therapeutic agent on hearing impairment in patients with chronic kidney disease. We conducted a randomized controlled trial of 40 chronic kidney disease patients not on dialysis with hearing impairment. Participants were randomly divided into two groups. One group received curcumin daily and the other received a placebo for 12 weeks. The interval between III and V waves, latency of wave V, auditory brain stem response (ABR) threshold, speech reception threshold (SRT), and speech discrimination score (SDS) were evaluated and analyzed before and after the intervention. After treatment, in the curcumin group, III–V waves interval and the latency of wave V were significantly reduced (P value < 0.0001), also ABR threshold was demonstrated a significant improvement (P value < 0.0001). In the trial group, the SDS was increased (P = 0.001) and the SRT was attenuated (P < 0.0001). We had either significant deterioration due to the course of the disease or insignificant changes in the placebo group. Daily administration of curcumin, can significantly improve hearing impairment in CKD patients. Accordingly, curcumin should be considered as a therapeutic option for treating hearing impairment in patients with chronic kidney disease.

The Effect of Antinociceptive Dose of Morphine on Cell Therapy in Rats with Spinal Cord Injury.

Spinal cord injury (SCI) is a sensory-motor injury. Today, combined treatments such as cell therapy along with drug therapy and their interactions are of interest. Morphine is an opioid drug used to relieve intolerable pain. This study aims to evaluate the impact of an antinociceptive dose of morphine (with minimal tolerance/dependence but effective pain relief) on cell therapy in SCI. The antinociceptive dose of morphine was determined in rats with SCI through the Hargreaves and naloxone-induced morphine withdrawal tests. The rats were then allocated to 5 groups: laminectomy, SCI, SCI + Morphine, SCI + cell therapy, SCI + Morphine + cell therapy. The antinociceptive dose (5 mg/kg) was administered on days 1, 4, 10, and 13 (i.p.) post-SCI. On day 7, Neural-like stem cells derived from adipose tissue were transplanted intraspinally into the injured animals, and they were monitored for 12 weeks. The outcomes were assessed using the BBB test, somatosensory evoked potential (SSEP), and histology. The BBB test indicated that morphine significantly hindered functional recovery post-cell transplantation compared to animals receiving only cell therapy (p < 0.05). In the SSEP test, the analysis of amplitude and latency of waves did not reveal a significant difference (p > 0.05). The histological results showed that cell therapy reduced the cavity size post-SCI, while morphine had no significant impact on it. Morphine at the antinociceptive dose significantly impairs motor recovery despite cell therapy. Nonetheless, there was no significant difference between groups in terms of sensory pathway outcomes.

N1 and LNC reveal the differential electrophysiological signatures of functional and hedonic images processing

In the process of creative sentence or phrase utilization, novel and appropriate evaluations cause the different brain responses observed in event-related potentials: the N400 reflects the novelty evaluation, whereas a late negative component marks appropriate processing. Do we have similar brain reactions in image perception when we rapidly browse pictures of objects with different novelty, functional/appropriate, and hedonic value? To explore this question, participants were presented with four novel object images with high or low functional and hedonic properties, as well as the ordinary product images, with the instruction to attentively observe and understand each image. We found a clear dissociation between processing of novelty and functional value: novelty objects produced negative deflections in the N2–N400 time window relative to the ordinary object images, whereas images with high functional value elicited a larger N2 and late negative waves (LNC) resembling the late component found for the appropriate phrases. Object images with high hedonic value, however, were associated with earlier aesthetic preference reflected in smaller N1 amplitudes, but failed to elicit a LNC effect. We therefore conclude that the processing of novelty, functional, and hedonic value are dissociation, and the perception of hedonic value is earlier (N1) than the novelty processing (N400) and the verification of functional value (LNC).