Significant Difference In Amplitude Research Articles

Differential effects of gender on mismatch negativity to violations of simple and pattern acoustic regularities.

IntroductionThe effects of gender on the mismatch negativity (MMN) potential have been studied using simple frequency deviants. However, the effects of gender on MMN to violations of abstract regularities have not yet been studied. Here, we addressed this issue and compared the effects of gender on simple and pattern frequency MMNs.MethodsMMN response was recorded from 29 healthy young adults, 14 females (mean age = 26.20 ± 2.17) and 15 males (mean age = 27.57 ± 2.24), using 32 scalp electrodes during simple and pattern frequency oddball paradigms and the mean amplitude, peak latency, and scalp topography of MMN evoked by each paradigm were compared between the two genders.ResultsThe peak latency of simple MMN was significantly longer in females (p < .05); however, its mean amplitude and topography were similar between the two genders (p > .05). There were no significant differences in peak latency, mean amplitude, and scalp topography of pattern MMN between the two genders (p > .05).ConclusionsBased on the obtained results, gender differently affects simple and pattern MMN. These findings may provide preliminary evidence for distinct effects of gender on various types of MMN.

Characteristic Deviations of Auditory Evoked Potentials in Individuals with Autism Spectrum Disorder.

Neurological, structural, and behavioral abnormalities are widely reported in individuals with autism spectrum disorder (ASD); yet there are no objective markers to date. We postulated that by using dominant and nondominant ear data, underlying differences in auditory evoked potentials (AEPs) between ASD and control groups can be recognized. The primary purpose was to identify if significant differences exist in AEPs recorded from dominant and nondominant ear stimulation in (1) children with ASD and their matched controls, (2) adults with ASD and their matched controls, and (3) a combined child and adult ASD group and control group. The secondary purpose was to explore the association between the significant findings of this study with those obtained in our previous study that evaluated the effects of auditory training on AEPs in individuals with ASD. Factorial analysis of variance with interaction was performed. Forty subjects with normal hearing between the ages of 9 and 25 years were included. Eleven children and 9 adults with ASD were age- and gender-matched with neurotypical peers. Auditory brainstem responses (ABRs) and auditory late responses (ALRs) were recorded. Adult and child ASD subjects were compared with non-ASD adult and child control subjects, respectively. The combined child and adult ASD group was compared with the combined child and adult control group. No significant differences in ABR latency or amplitude were observed between ASD and control groups. ALR N1 amplitude in the dominant ear was significantly smaller for the ASD adult group compared with their control group. Combined child and adult data showed significantly smaller amplitude for ALR N1 and longer ALR P2 latency in the dominant ear for the ASD group compared with the control group. In our earlier study, the top predictor of behavioral improvement following auditory training was ALR N1 amplitude in the dominant ear. Correspondingly, the ALR N1 amplitude in the dominant ear yielded group differences in the current study. ALR peak N1 amplitude is proposed as the most feasible AEP marker in the evaluation of ASD.

Discrimination of α-Thrombin and γ-Thrombin Using Aptamer-Functionalized Nanopore Sensing.

Protein detection and identification at the single-molecule level are major challenges in many biotechnological fields. Solid-state nanopores have raised attention as label-free biosensors with high sensitivity. Here, we use solid-state nanopore sensing to discriminate two closely related proteins, α-thrombin and γ-thrombin. We show that aptamer functionalization improves protein discrimination thanks to a significant difference in the relative current blockade amplitude. To enhance discrimination, we postprocessed the signals using machine learning and training algorithms and we were able to reach an accuracy of 98.8% using seven features and ensemble methods.

Leadless pacemakers: does location matter?

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Leadless pacemakers (LPs) provide a viable alternative for patients who have an indication for pacing where transvenous pacing is not desirable or possible. Registries have demonstrated stable performance associated with LPs. There is preference towards implanting LPs into the trabeculated septum rather than the apex or free wall. We report our experience with the impact of the implantation site on acute and long-term electrical performance of LPs. Methods We ran a retrospective analysis on the first 100 LPS implanted at our centre. Two independent observers reviewed the fluoroscopic images and post-implant chest x-rays to classify the LPs’ positions. We obtained the recorded pacing threshold , R-wave amplitude and impedance of the devices at the time of implant and at the latest available routine device follow-up. We used one-way ANOVA testing to compare the acute and long-term electrical performance of the LPs between different implantation sites. Results We were able to classify the site of the LPs implants in a total of 90 patient. 84 Patients (60% male) 57.3± 22.16 years were included .23.8% of the patients presented with syncope. Indications for pacing were symptomatic sinus node dysfunction (33.3%), high grade AV block (34.5%), bradyarrhythmia associated with atrial tachyarrhythmias (28.6%) and other indications (3.6%). We had a 100% successful implant rate, 85.7% required ≤2 attempts and 71.4% required one attempt. A total of 32 implants were in the apex (38.1%), 26 in mid-septum (30.9 %), 13 in the apical septum (15.5%), 12 on the septal aspect of the right ventricular inflow (14.3%) and 1 implant (1.2%) in the septum of the RV outflow tract. The follow up period of the 84 patients was 3.09 ± 1.97 years. 100% of the LPs had the pacing thresholds &amp;lt;2.0 V @0.24 ms at the time of implant. Pacing threshold, R-wave amplitude, and impedance averaged at 0.67 ± 0.41 V, 10.86 ± 5.41 mV, and 775 ± 193.28 Ohms respectively at the time of implantation and 0.66 ± 0.39 V, 14.08 ± 6.14 mV, and 564.29 ± 96.76 Ohms at the last device check. There was no statistically significant difference in either the pacing thresholds or the impedance between implant sites. Post hocTukey’s analysis (excluding the outflow tract case) demonstrated significant statistical difference in the R-wave amplitudes between implants at the apex and the mid-septum both at the time of implantation (12.9 ± 6.1 mV and 8.53 ± 2.84 mV; p = 0.0196) and at follow up (15.97 ± 5.35 mV and 11.52 ± 5.01 mV; p = 0.0415). There were no differences between other sites Conclusions Our analysis demonstrated that aside from the difference between the sensed R wave amplitudes between LPs implanted at the apex and those implanted at mid-septum , there was no statistically significant difference in the acute or the long term electrical performance of implanted LPs regardless of the implantation site. A limitation to our analysis is the relatively low number of LP implants included in our analysis. Abstract Figure. Mean of parameters by validated position

Autonomic dysfunction detection by an automatic pupillometer as a non-invasive test in patients recovered from COVID-19.

PurposeTo recognize dysfunctions in the autonomic nervous system (ANS) with changes in dynamic and static pupillary responses in patients who recovered from coronavirus disease-2019 (COVID-19)MethodsOne month after recovery from COVID-19, patients were subjected to eye examinations. Pupillary responses were measured using a pupillometry system. Dynamic pupil parameters (i.e., pupil contraction amplitude, pupil dilatation latency, pupil contraction latency, pupil dilatation duration, pupil dilatation velocity, pupil contraction duration, pupil contraction velocity, resting pupil diameter [PD]) and static pupil parameters (i.e., mesopic PD, scotopic PD, high photopic PD, and low photopic PD) were registered.ResultsAlthough high photopic and scotopic PDs were significantly higher in patients recovering from COVID-19 than in healthy controls (P = 0.04 and P = 0.002), no statistically significant difference was found in mesopic and low photopic PD (P = 0.19 and P = 0.41). Regarding dynamic pupillometry parameters, resting PD and pupil contraction velocity (P = 0.04 and P = 0.02, respectively) were significantly higher in patients recovering from COVID-19 than in healthy controls (P < 0.001 and P < 0.001, respectively), whereas pupil dilatation latency and pupil contraction duration were lower in these patients than in healthy controls (P = 0.01 and P = 0.008, respectively). No significant differences in pupil contraction amplitude, pupil dilatation duration, pupil contraction latency, and pupil dilatation velocity were found between the study groups (P = 0.93, P = 0.91, P = 0.42, and P = 0.48, respectively).ConclusionPupil responses, which are controlled by the ANS, were impaired in patients recovering from COVID-19. Pupillometry shows promise as a non-invasive, easy-to-apply diagnostic technology for detecting autonomic dysfunction in patients recovering from COVID-19.Clinical trial registrationNot applicable.

Montage-related Variability in the Characteristics of Envelope Following Responses

The study aimed to compare two electrode montages commonly used for recording speech-evoked envelope following responses. Twenty-three normal-hearing adults participated in this study. EFRs were elicited by a naturally spoken, modified /susa∫i/ stimulus presented at 65 dB SPL monaurally. EFRs were recorded using two single-channel electrode montages: Cz-nape and Fz-ipsilateral mastoid, where the noninverting and inverting sites were the vertex and nape, and the high forehead and ipsilateral mastoid, respectively. Montage order was counterbalanced across participants. Envelope following responses amplitude and phase coherence were significantly higher overall in the Cz-nape montage with no significant differences in noise amplitude. Post hoc testing on montage effects in response amplitude and phase coherence was not significant for individual stimuli. The Cz-nape montage also resulted in a greater number of detections and analyzed using the Hotelling's T2. Electrode montage influences the estimated characteristics of speech-evoked EFRs.

Contribution of the peroneus longus neuromuscular compartments to eversion and plantarflexion of the ankle.

Compartmentalization of animal and human skeletal muscle by multiple motor nerve branches known as the neuromuscular compartment (NMC) has been observed primarily in muscles that participate in a plane of motion. In this context, the peroneus longus muscle contributes to eversion and plantarflexion of the ankle and the presence of NMCs has been reported. However, no research has reported the selective activation of the compartments of the peroneus longus during the performance of different ankle movements. The purpose of this research was to determine the contribution of peroneus longus NMCs, through multi-channel surface electromyography (sEMG), to eversion and plantarflexion movements. Multi-channel sEMG was recorded from the peroneus longus muscle by using an electrode grid during eversion and plantarflexion of the ankle at 10%, 30%, 50%, and 70% of maximal voluntary isometric contraction (MVIC). The root mean square and displacement of the center of mass position in the X (COMx) and Y (COMy) components were calculated. The primary finding was that eversion showed significantly higher sEMG amplitude than plantarflexion in the posterior compartment in low, moderate, and high percentages of MVIC. However, no significant difference in sEMG amplitude was observed in the anterior compartment between eversion and plantarflexion. In addition, a posterior displacement of the COMx in eversion compared to plantarflexion in all MVIC percentages, with greater topographic distancing of the COMx at higher levels of activation. In conclusion, the peroneus longus muscle presented NMCs; the anterior compartment contributed to both eversion and plantarflexion movements, whereas the posterior compartment mainly contributed to the eversion movement of the ankle in low, moderate, and high percentages of MVIC.

Glutamatergic dysfunction in resistant obsessive-compulsive disorder: An auditory mismatch negativity study

IntroductionObsessive-compulsive disorder (OCD) patients with poor response to serotonin reuptake inhibitors (SRIs) may have dysfunction involving other neurotransmitters, including glutamate. Mismatch negativity (MMN), an event-related potential dependent on glutamatergic functioning, has not been studied in the adult OCD population and SRI non-responders.ObjectivesTo compare the amplitude of MMN between OCD subjects who have responded(R) and not responded(NR) to SRIs, with healthy volunteers(HV).MethodsMMN was measured in 15 OCD subjects fulfilling DSM-IV criteria (8 non-responders and 7 responders) and 22 healthy volunteers. Auditory MMN was measured using a multi-feature paradigm consisting of two variants each in frequency, duration, and intensity domains. EEG was recorded using 64 channel electrodes at 1000Hz. Epochs of 700 ms were extracted for each stimulus. MMN was evaluated as peak difference between the deviant and standard stimulus. MMN amplitudes at Fz were used for comparison between the groups using Kruskal-Wallis test followed by posthoc analysis, with significance set at p&lt;0.05.ResultsThere was no significant difference in age/gender distribution between the three groups and duration of illness between the two OCD groups. There was a significant difference in MMN amplitude of a frequency deviant between the three groups (H=7.312,P=0.026). Post-hoc pairwise analyses revealed a significant reduction in MMN amplitude in NRs as compared to the HV group (H=10.9,P=0.04).ConclusionsThe results are suggestive of glutamatergic dysfunction in OCD subjects with poor response to SRIs. The findings have to be replicated in larger samples employing other paradigms to evaluate glutamatergic functioning and have future potential in understanding treatment response to SRIs.

The biomechanical role of the lacertus fibrosus of the biceps brachii Muscle

The lacertus fibrosus (LF) is involved in various surgeries. However, the biomechanical contribution of the LF remains unclear. The aim of this study was to determine the role of the lacertus fibrosus on the elbow and forearm kinematics and on the biceps brachii muscle lever arms. This biomechanical study was performed on seven fresh-frozen upper limbs of cadavers. Elbow flexion, forearm supination, and biceps brachii muscle lever arms were analyzed in the intact conditions (I) and after superficial (R) and deep part (R2) of the lacertus fibrosus release, respectively. Elbow flexion shows a significant difference (p < 0.0001) between I, R, R2. Abduction/adduction shows a significant difference between I-R (p < 0.0001) and I-R2 (p < 0.0001). Supination does not show a significant difference in mean maximum amplitude, but between 40 and 70%, there are significant differences. There is a significant mean decrease of lever arm in flexion (28%) and supination (50%) after superficial and deep part of the lacertus fibrosus release. The results of this study show that the lacertus fibrosus increases the lever arm during flexion and supination. It limits the flexion and abduction of the elbow and supination of the forearm. Lacertus fibrosus maintains the rhythmicity between the elbow flexion and supination of the forearm. Basic science study, biomechanics.

Effects of spatial separation with better- ear listening on N1–P2 complex

ObjectiveThe purpose of this study was to determine better- ear listening effect on spatial separation with the N1–P2 complex. MethodsTwenty individuals with normal hearing participated in this study. The speech stimulus /ba/ was presented in front of the participant (0°). Continuous Speech Noise (5 dB signal-to-noise ratio) was presented either in front of the participant (0°), left-side (-90°), or right-side (+90°). N1- P2 complex has been recorded in quiet and three noisy conditions. ResultsThere was a remarkable effect of noise direction on N1, P2 latencies. When the noise was separated from the stimulus, N1 and P2 latency increased in terms of when noise was co-located with the stimulus. There was no statistically significant difference in N1-P2 amplitudes between the stimulus-only and co-located condition. N1-P2 amplitude was increased when the noise came from the sides, according to the stimulus-only and co-located conditions. ConclusionThese findings demonstrate that the latency shifts on N1-P2 complex explain cortical mechanisms of spatial separation in better-ear listening.

A resting-state functional MRI study in patients with vestibular migraine during interictal period.

To evaluate the spontaneous neuronal activities and the changes of brain functional network in patients with vestibular migraine (VM). Three groups including18 patients with VM, 21 patients with migraine without aura (MWoA) and 21 healthy controls (HCs) underwent the scanning of the resting-state fMRI. Covariance analysis and bonferroni multiple comparisons were used to obtain brain regions with significant differences in amplitude of low-frequency fluctuation (ALFF) values. Furthermore, the brain regions with the most significant differences of ALFF values were recognized as a region of interest (ROI) and functional connectivity (FC) analysis was performed in these regions. (1) ALFF: Compared with HCs, patients with VM showed significantly lower ALFF in the right putamen (P < 0.05), and significantly higher ALFF in the right lingual gyrus (P < 0.05). In addition, compared with MWoA patients, patients with VM showed significantly higher ALFF in the right lingual gyrus (P < 0.05). (2) Compared with HCs, VM patients showed significantly higher FC among the cerebellum, the left dorsolateral superior frontal gyrus and the right putamen (P < 0.05) but significantly lower FC among the left median cingulate, paracingulate gyri and the right putamen (P < 0.05). Compared with MWoA patients, VM patients showed significantly higher FC between the cerebellum and the right putamen (P < 0.05) but significantly lower FC among the left median cingulate, paracingulate gyri and the right putamen (P < 0.05). There are functional abnormalities in nociceptive, vestibular and visual cortex regions in patients with VM during the interictal period.

Effects of excessive violent video game playing on verbal memory: an event-related brain potentials study.

The goal of the study was to investigate temporal dynamics of excessive violent game playing. We compared behavioral data and event-related potentials (ERPs) of excessive video game players (EVGPs, n = 21) and non-players (NPs, n = 21) using a classical learning, cued recall and recognition paradigm, featuring violent and non-violent words. During the recognition phase, EVGPs performed better for violent words, but worse for non-violent words compared to NPs. Also, EVGPs showed slower reaction times than NPs when responding to new violent words. We found significant group differences in parietal P300 and FN400 amplitudes. The EVGP group showed larger P300 amplitudes for violent words, and more negative FN400 amplitudes for new violent words compared to NPs. The results imply that EVGPs differ from NPs in their cognitive and ERP responses to violent and non-violent verbal stimuli. The cognitive processes of EVGPs are consistent with a model of attention and memory bias rather than with desensitization to violence.

Examining motor evoked potential amplitude and short-interval intracortical inhibition on the up-going and down-going phases of a transcranial alternating current stimulation (tacs) imposed alpha oscillation.

Many brain regions exhibit rhythmical activity thought to reflect the summed behaviour of large populations of neurons. The endogenous alpha rhythm has been associated with phase-dependent modulation of corticospinal excitability. However, whether exogenous alpha rhythm, induced using transcranial alternating current stimulation (tACS) also has a phase-dependent effect on corticospinal excitability remains unknown. Here, we triggered transcranial magnetic stimuli (TMS) on the up- or down-going phase of a tACS-imposed alpha oscillation and measured motor evoked potential (MEP) amplitude and short-interval intracortical inhibition (SICI). There was no significant difference in MEP amplitude or SICI when TMS was triggered on the up- or down-going phase of the tACS-imposed alpha oscillation. The current study provides no evidence of differences in corticospinal excitability or GABAergic inhibition when targeting the up-going (peak) and down-going (trough) phase of the tACS-imposed oscillation.

Precipitation Diurnal Cycle over the Maritime Continent Modulated by the Climatological Annual Cycle

AbstractThe modulation of the diurnal cycle (DC) of precipitation over the Maritime Continent (MC) by the background annual cycle mean state was studied for the period of 1998–2014 through observational analyses and high-resolution simulations using the Weather Research and Forecasting (WRF) Model. The observational analyses reveal that there are statistically significant differences in the DC amplitude between boreal winter and summer. The amplitude of precipitation DC reduces by about 35% during boreal summer compared to boreal winter, especially over the MC major islands and adjacent oceans. A precipitation budget analysis indicates that the DC amplitude difference is primarily attributed to vertically integrated convergence of the mean moisture by diurnal winds. The relative roles of the background dynamic and thermodynamic states in causing the enhanced diurnal wind activity in boreal winter are further investigated through idealized WRF simulations. The results show that the seasonal mean background moisture condition is most critical in inducing the winter–summer difference of the precipitation DC over the MC, followed by atmospheric static stability (i.e., vertical temperature gradient) and circulation conditions.

Study of ocular vestibular evoked myogenic potentials in benign paroxysmal positional vertigo associated with Meniere's disease

Objective:The aim of this study is to explore the characteristics of ocular muscle vestibular evoked myogenic potential （oVEMP） in patients with Meniere's disease and benign paroxysmal positional vertigo （BPPV-MD）, and to explore the clinical characteristics of oVEMP frequency amplitude ratio （FAR）. Methods:Forty-one patients with unilateral MD diagnosed in the outpatient clinic from January 2016 to April 2019 were selected, of which 15 patients with BPPV-MD were set as BPPV-MD group, and 26 patients with unilateral MD were set as MD group. During the same period, 30 healthy volunteers matched in age and gender were selected as the control group. All the individuals underwent oVEMP and cVEMP recording for 500 Hz and 1000 Hz tone burst. The oVEMP and cVEMP response rate, N1 and P1 waves latency, N1-P1 wave amplitude and 1000/500 Hz FAR of the affected and contralateral ears of the three groups were compared and analyzed by SPSS 20.0 software. The receiver operating characteristics curves were obtained for finding out the criterion point, sensitivity, and specificity of 1000/500 Hz FAR for the diagnosis of BPPV-MD. Results:In response to 500 Hz tone burst, oVEMP response rates in the affected lateral ears of BPPV-MD group, MD group and right ears of control group were 46.67%, 46.15% and 76.67%, respectively; the rates for the 1000 Hz-oVEMP of the three groups were 53.33%, 46.15% and 63.33%, respectively. By the 500 Hz air-conducted tone-burst stimulus, the oVEMP N1 and P1 latency of the affected ears in the BPPV-MD group was longer than that in the MD group and the control group（P<0.05）. By the stimulus of 1000 Hz tone burst, the oVEMP N1 and P1 latency of the affected ears in BPPV-MD group and MD group was longer than that in control group（P<0.05）. At 500 Hz, the oVEMP amplitude of the affected ears in BPPV-MD group and MD group was lower than that in the right ears of the control group（P<0.05）. There was no statistically significant difference in the N1-P1 amplitudes of oVEMP in the three groups under the stimulation of 1000 Hz tone burst（P>0.05）. The FAR for 1000/500 Hz of the affected ears in BPPV-MD group and MD group was higher than that in control group（P<0.05）, but there was no significant difference between BPPV-MD group and MD group（P>0.05）. Conclusion:When FAR is greater than 0.84, which indicates that the pathophysiologic factor is accumulation of excessive amounts of endolymph; when FAR is greater than 1.79, which suggests that the otolitic membrane of the elliptic cyst is damaged by the hydrops of the labyrinthus. The FAR of BPPV-MD can be used as one of the indicators to evaluate the function of the utricle.

Comparison of Bone-Conducted Cervical VEMPs Elicited by B71 and B81 Bone Vibrators

A variety of stimulus delivery methods can elicit vestibular evoked myogenic potentials (VEMPs). The current study compared bone conduction (BC) cervical VEMPs (cVEMPs) across two different clinical bone vibrators. It was hypothesized that the B81 transducer would be more effective for producing larger BC-cVEMP peak to peak amplitudes due to its low-frequency advantages in pure-tone audiometry applications. Twenty young adults under the age of 40 years with no reported history of hearing or balance disorders participated in the study. BC cVEMPs were elicited using two clinical bone transducers: the Radioear B71 bone vibrator and the Radioear B81 bone vibrator. Both transducers were calibrated using the acoustic method of calibration before data collection, and the linear dynamic range of the transducers was determined. Participants were asked to sit and match a fixed electromyography (EMG) target level of 100 µV, while BC cVEMPs were recorded using stimulus frequencies of 250, 500, and 750 Hz. Statistically significant differences in raw amplitude at 250 and 750 Hz between the B71 and B81 were observed; the B71 produced larger peak to peak amplitudes over the B81. At 500 Hz, larger amplitudes were observed with the B71, but results were not statistically significant. The B71 produced significantly lower cVEMP thresholds at all three frequencies. Across both transducers, 500 Hz produced the largest peak to peak amplitude compared with 250 and 750 Hz. Peak to peak amplitude did not increase above 55 dB nHL for 250 and 500 Hz, but amplitude continued to increase at 750 Hz. The present study found statistically significant differences in BC-cVEMP amplitude and threshold between the B71 and B81, but results were not what we hypothesized. In general, the B71 elicited larger BC-cVEMP amplitudes and lower thresholds compared with the B81. Additionally, 500 Hz was found to be the best frequency for both BC transducers, contrasting previous studies suggesting lower frequencies yield larger BC-cVEMP amplitudes. It is possible that these average differences could also be clinically significant when looking at individual amplitude differences. Larger peak to peak amplitudes at 500 Hz may be partially due to the underlying physical levels used in the current study, as well as the output spectra of the transducers, and may explain the larger response amplitudes observed at 500 Hz compared with 250 Hz.

Motor unit action potential amplitude during low torque fatiguing contractions versus high torque non-fatiguing contractions: a multilevel analysis.

The ability to maintain an absolute, submaximal torque level during fatiguing contractions is controlled, in part, by the recruitment of larger motor units. These motor units are commonly identified based on greater action potential peak-to-peak amplitude values. It is unclear, however, if motor unit action potential (MUAP) amplitude values during low torque, fatiguing contractions reach similar levels as those observed during non-fatigued, high torque contractions. To establish a clearer understanding of motor unit control during fatigue, we compared MUAP amplitude during 50 and 80% maximum voluntary contraction (MVC) torque contractions and at the beginning, middle, and end of a 30% MVC fatigue protocol. Eleven untrained men (mean age = 24years) performed isometric contractions at 50 and 80% MVC, followed by repeated contractions at 30% MVC. Surface electromyographic (EMG) signals were detected from the vastus lateralis and decomposed to quantify the peak-to-peak amplitude of individual MUAPs. A two-level multilevel model was estimated, allowing examination of simultaneous measures of MUAP amplitude within participants and controlling for the dependence between measures within participants. Results from the multilevel analyses suggested that there were not statistically significant differences in MUAP amplitude between 80% MVC and end fatigue. Separate repeated-measures analyses of variance indicated that there were not statistically significant mean differences in greatest MUAP or surface EMG amplitude between 80% MVC and end fatigue. MUAP and surface EMG amplitude values during a 30% MVC fatiguing protocol appear to be comparable to those observed during a non-fatigued 80% MVC condition.

Can Narrow Band Chirp Stimulus Shake the Throne of 500 Hz Tone Burst Stimulus for Cervical Vestibular Myogenic Potentials?

Background and ObjectivesThe aim of the study was to compare effects of tone-burst (TB) and narrow-band (NB) Claus Elberling (CE)-chirp stimuli on amplitude, latency and interaural asymmetry ratio (IAR) of cervical vestibular evoked myogenic potentials (cVEMP) in healthy individuals.Subjects and MethodsThe study included 50 healthy volunteers. cVEMP procedure was carried out using 500 Hz TB and NB-CE-chirp stimulus (360-720 Hz, up-chirp) in random order. cVEMP were recorded at 100 dB nHL. For each ear and each stimulus, P1 latency, N1 latency and P1N1 amplitude were measured. IAR was also calculated.ResultsMean age was 26.66±9.48 years. cVEMP’s in response to both TB and NB CE-chirp stimuli were obtained in all subjects. No statistically significant difference in P1 latency, N1 latency, and P1N1 amplitude was found between the right and left ears for both TB and NB CE-chirp stimuli (p>0.05). In both sides, P1 and N1 latencies were significantly shorter in NB CE-chirp stimulation compared to TB stimulation (p=0.000). In both sides, no statistically significant difference was found in P1N1 amplitude between two types of stimuli (p>0.05).ConclusionsThe chirp stimulus produces robust but earlier cVEMP than TB does. This largest series study on NB chirp cVEMP shows that NB chirp is a good and new reliable alternative.

The neural differences of arithmetic verification performance depend on math skill: Evidence from event-related potential.

AimMath skill is a basic need for an individual, as a career prospect. However, little is known about early brain processes of arithmetic between individuals with different math skill. Therefore, we questioned the modulation of the amplitude of an early negative component by math skill level in an arithmetic verification paradigm using event‐related potential (ERP).MethodsThirty‐six right‐handed participants were assigned in two groups of high‐ and low‐performing students. Their electroencephalogram was recorded while they completed an arithmetic verification task. Simple arithmetic operands were made by random digits from 1 to 9. Addition and subtraction operations were equally used in correct and incorrect responses. The accuracy scores, reaction times, and peak amplitude of the negativity in 200‐400 ms time window were analyzed.ResultsThe high‐performing group showed significantly higher response speeds, and they were more accurate than the low‐performing group. The group × region interaction effect was significant. The high‐performing group showed a significantly greater negativity, particularly in parietal region, while the low‐performing group showed a significantly deeper negativity in frontal and prefrontal region. In the low‐performing group, there were significant peak amplitude differences between the anterior and posterior areas. However, such differences were not detected in the high‐performing group.ConclusionStudents with different mathematical performance showed distinct patterns in early processing of arithmetic verification, as reflected by differences in negativity at 200‐400 ms at anterior and posterior. This suggests that ERPs could be used to differentiate math mastery at neural level which is beneficial in educational and clinical contexts.

Effect of Sudarsankriya yoga practices on P300 amplitude and latency.

The cognitive ability which was perceived as a constant trait, is now understood to be upgraded by adaptive and extended training. Yoga practices are known to sharpen the intellect and enhance concentration. In the initial period of practicing yoga as an alternative/supporting tool to medical line of treatment, it is essential to investigate effect of yoga on cognitive ability using objective method, in order to establish evidences. Hence, aim of this study was to explore the effect of regular practice of sudarsankriya yoga on auditory event related potential (P300) by recording and comparing peak latency and amplitude. The participants were divided into three groups with Group I and Group II participants practicing sudarsankriya yoga for more than 36 months and less than 36 months respectively. Group III were non-practitioners with no prior practice of any form of yoga. Twenty participants in each group with a total of 60 participants between 40 to 65 years of age were recruited for the study. Results revealed a significant difference for mean latency and amplitude between three groups. Findings of the current study suggest that sudarsankriya yoga practices slows down the process of aging effect or maintains on cognitive ability in adults.