scholarly journals Mismatch Negativity in Children: Reference Values

2018 ◽  
Vol 23 (02) ◽  
pp. 142-146 ◽  
Author(s):  
Dulce Azevedo Ferreira ◽  
Claudine Devicari Bueno ◽  
Sady Selaimen de Costa ◽  
Pricila Sleifer

Introduction The Mismatch Negativity (MMN) auditory evoked potential evaluation is a promising procedure to assess objectively the ability of auditory discrimination. Objective To characterize the latency and amplitude values of MMN in children with normal auditory thresholds and without auditory complaints. Methods Children between 5 and 11 years old participated in the present study. All participants underwent acoustic immittance measurements and tonal and vocal audiometry. The MMN was recorded with the MASBE ATC Plus system (Contronic, Pelotas, RS, Brazil). The electrodes were fixed in Fz (active electrode), Fpz (ground electrode) and in M2 and M1 (references electrodes). The intensity used was 80 dBHL, the frequent stimulus was 1,000 Hz and the rare stimulus was 2,000 Hz. The stimuli were presented in both ears separately. Results For the female group, the mean latencies and amplitude of MMN were 177.3 ms and 5.01 μV in the right ear (RE) and 182.4 ms and 5.39 μV in the left ear (LE). In the male group, the mean latencies were 194.4 ms in the RE and 183.6 ms in the LE, with an amplitude of 5.11 μV in the RE and 5.83 μV in the LE. There was no statistically significant difference between ears (p = 0.867 - latency and p = 0.178 - amplitude), age (p > 0.20) and the gender of the participants (p > 0.05). Conclusion Using the described protocol, the mean latency value of MMN was 184.0 ms for RE and 182.9 ms for LE, and the amplitude was 5.05 μV and 5.56 μV for the left and right ears, respective.

2016 ◽  
Vol 21 (03) ◽  
pp. 232-238 ◽  
Author(s):  
Laura Schwade ◽  
Dayane Didoné ◽  
Pricila Sleifer

Introduction Mismatch Negativity (MMN) corresponds to a response of the central auditory nervous system. Objective The objective of this study is to analyze MMN latencies and amplitudes in normal-hearing adults and compare the results between ears, gender and hand dominance. Methods This is a cross-sectional study. Forty subjects participated, 20 women and 20 men, aged 18 to 29 years and having normal auditory thresholds. A frequency of 1000Hz (standard stimuli) and 2000Hz (deviant stimuli) was used to evoked the MMN. Results Mean latencies in the right ear were 169.4ms and 175.3ms in the left ear, with mean amplitudes of 4.6µV in the right ear and 4.2µV in the left ear. There was no statistically significant difference between ears. The comparison of latencies between genders showed a statistically significant difference for the right ear, being higher in the men than in women. There was no significant statistical difference between ears for both right-handed and left-handed group. However, the results indicated that the latency of the right ear was significantly higher for the left handers than the right handers. We also found a significant result for the latency of the left ear, which was higher for the right handers. Conclusion It was possible to obtain references of values for the MMN. There are no differences in the MMN latencies and amplitudes between the ears. Regarding gender, the male group presented higher latencies in relation to the female group in the right ear. Some results indicate that there is a significant statistical difference of the MMN between right- and left-handed individuals.


2009 ◽  
Vol 79 (2) ◽  
pp. 265-270 ◽  
Author(s):  
Claudia A. Reicheneder ◽  
Peter Proff ◽  
Uwe Baumert ◽  
Tomas Gedrange

Abstract Objective: To test the null hypothesis that there are no differences between children and adults in maximum laterotrusion and maximum retrusion on the right and left sides. Materials and Methods: This population-based study included 81 randomly selected children between the ages of 6 and 10 years and 67 adults. Kinematic variables were measured with the ultrasonic JMA-System for registration. Results: The mean maximum laterotrusion of the children's group (10.6 ± 1.5 mm on the left, 11.0 ± 1.7 mm on the right) was significantly smaller than that of the adult group (11.7 ± 2.0 mm on the left, 12.2 ± 1.7 mm on the right). The maximum laterotrusion of the children's group corresponded to about 90% on the left and right sides of that of the adult group. The mean maximum retrusion of the children's group was significantly bigger than that of the adult group. There, the adult values corresponded to 66.7% on the left and 50% on the right side of the children's values. No significant difference in maximum laterotrusion and retrusion was noted on the right and left sides, and no significant differences according to gender specificities were observed in either group. Conclusions: The hypothesis is rejected. In development of the temporomandibular joint, maximum laterotrusion on the right and left sides increases significantly with age, and maximum retrusion decreases significantly with age.


2019 ◽  
Vol 24 (02) ◽  
pp. e154-e159
Author(s):  
Mirtes Brückmann ◽  
Michele Vargas Garcia

Abstract Introduction Mismatch negativity (MMN) is a long latency auditory evoked potential, represented by a negative wave, generated after the potential N1 and visualized in a resulting wave. Objective To identify the time of occurrence of MMN after N1, elicited with verbal and nonverbal stimuli. Methods Ninety individuals aged between 18 and 56 years old participated in the study, 39 of whom were male and 51 female, with normal auditory thresholds, at least 8 years of schooling, and who did not present auditory processing complaints. All of them underwent audiologic anamnesis, visual inspection of external auditory meatus, pure tone audiometry, speech audiometry, acoustic immittance measures and the dichotic sentence identification test as a screening for alterations in auditory processing, a requirement to participate in the sample. The MMN was applied with two different stimuli, with these being da/ta (verbal) and 750 Hz and 1,000 Hz (nonverbal). Results There was a statistically significant difference between the latency values of the N1 potential and the MMN with the two stimuli, as well as between the MMN with verbal and nonverbal stimuli, and the latency of the MMN elicited with da/ta being greater than that elicited with 750 Hz and 1,000 Hz, which facilitated its visualization. Conclusion The time of occurrence of MMN after the N1 elicited with verbal stimuli was 100.4 ms and with nonverbal stimuli 85.5 ms. Thus, the marking of the MMN with verbal stimuli proved to be more distant from N1 compared with the nonverbal stimuli.


2017 ◽  
Vol 19 (3) ◽  
pp. 165
Author(s):  
Audrei Thayse Viegel de Ávila ◽  
Pricila Sleifer ◽  
Vanessa Onzi Rocha ◽  
Rafael Fabiano Machado Rosa ◽  
Paulo Ricardo Gazzola Zen

A realização dos Potencias Evocados Auditivos de Longa Latência - PEALL em indivíduos com síndrome de Down - SD podem fornecer dados importantes sobre o processamento cerebral da audição e suas associações necessária para um bom desenvolvimento da linguagem. Analisar latências e amplitudes obtidas no registro dos componentes exógenos e endógeno dos PEALL, em adolescentes com SD, assim como correlacionar os achados entre os gêneros. Foram incluídos no estudo onze adolescentes com SD, que não apresentassem perdas auditivas, sete do gênero feminino e quatro do masculino, com idade mínima de 13 e máxima de 17 anos. Foi realizada avaliação auditiva periférica básica e pesquisa dos PEALL, incluindo o potencial cognitivo (P3). As médias encontradas para as latências dos componentes exógenos P1, N1, P2, N2 foram, respectivamente, de 110,2ms; 180,3ms; 322,2ms e 492,5ms para orelha direita e 100,2ms; 168,3ms; 323,1ms e 497,5ms para orelha esquerda. As amplitudes médias encontradas para P1N1 e N1P2 foram, respectivamente, 15,0μV e 16,0μV para orelha direita e 16,8μV e 18,7μV para orelha esquerda. A média encontrada para a latência da onda P3 foi 651,7ms e amplitude média foi 10,0μV. Houve diferença significativa entre gêneros para a latência de N1 na orelha direita (p=0,020). Na análise das ondas P1, N1, P2, N2 e P3 foi possível observar aumento das latências e amplitudes dentro dos padrões de normalidade. Foi verificada correlação significativa entre gêneros somente para as latências de N1 na orelha direita, tendo o gênero feminino latências superiores. Sugere-se a realização de estudos, que usem os procedimentos de PEALL para avaliar e monitorar, objetivamente, as intervenções e evoluções terapêuticas na SD.Palavra-chave: Audição. Eletrofisiologia. Potenciais Evocados Auditivos.AbstractThe accomplishment of Late Latency Auditory Evoked Potential - LLAEP in individuals with Down syndrome - DS can provide important data from brain processing of hearing and their associations necessary for a good language development. To evaluate latencies and amplitudes obtained from exogenous and endogenous components of LLAEP in teenagers with DS and correlate the findings between genders. This study included 11 teenagers with DS and without hearing loss, seven females and four males with minimum age 13 and maximum 17 years. Hearing evaluation and research of the LLAEP were performed, including cognitive potential (P3). The averages found for the latencies of exogenous components P1, N1, P2, N2 were respectively 110,2ms; 180,3ms; 322,2ms and 492,5ms to right ear and 100,2ms; 168,3ms; 323,1ms and 497,5ms to left ear. The averages found for the amplitudes P1N1 and N1P2 were respectively 15.00μV and 16.0 μV to right ear and 16.8μV and 18.7μV to left ear. The mean found for the latency of the P3 wave was 651.7 ms and mean amplitude 10.0μV. There was a significant difference between genders for N1 latency in the right ear (p=0.020). Analyzing P1, N1, P2, N2 and P3 waves, it was observed increased latencies and amplitudes within the normal range. Significant correlation was observed between genders only for N1 latencies for the right ear, females had higher latencies. It is suggested to carry out studies that use the LLAEP procedures to evaluate and objectively monitor the interventions and therapeutics evolutions in DS.Keywords: Hearing. Electrophysiology. Evoked Potentials, Auditory.


2019 ◽  
Vol 133 (06) ◽  
pp. 515-519 ◽  
Author(s):  
N A Fitchat ◽  
S Maharaj ◽  
M O Kwete

AbstractBackgroundZenker's diverticulum is a pharyngoesophageal outpouching of mucosa and submucosa through Killian's dehiscence.ObjectiveTo investigate the propensity for Zenker's diverticulum to occur on the left side by examining muscle thickness in Killian's dehiscence, and to explore correlations between muscle thickness, sex, height and age.MethodsThe study included 109 Caucasian cadavers, 52 male and 57 female. The mean thickest and thinnest measurements of left medial, left lateral, right medial and right lateral aspects of Killian's dehiscence were calculated. The paired student's t-test was used to determine significance.ResultsThe average left muscle layer was significantly thinner than the right muscle layer, in both medial and lateral aspects. Furthermore, medial muscle thickness was significantly thinner than its respective lateral aspect for both the left and right sides. No correlations were found between muscle thickness and cadavers’ sex, length or stature, or age.ConclusionThere was a significant difference in muscle thickness between the left and right sides of Killian's dehiscence. The findings suggest there is a reason why Zenker's diverticulum occurs predominantly on the left side. The study also showed a significant difference in muscle thickness between the medial and lateral aspects of Killian's triangle.


2016 ◽  
Vol 26 (3) ◽  
pp. 368 ◽  
Author(s):  
Anna Caroline Silva de Oliveira ◽  
Simone Fiuza Regaçone ◽  
Ana Claudia Figueiredo Frizzo

Introduction: The middle-latency auditory evoked potential is used to evaluate any abnormality that might impair the central auditory pathways, which are situated between the brain stem and the primary auditory cortex. Objective: To analyse the middle-latency auditory evoked potentials in children. Methods: This is a descriptive and cross-sectional study. Pure-tone audiometry was performed, and if no change was detected, Biologic’s portable Evoked Potential System (EP) was used to measure auditory evoked potentials. The identification of the responses was performed using electrodes positioned at C3 and C4 (left and right hemispheres) in reference to ears A1 and A2 (left and right earlobe). These were ipsilaterally and contralaterally paired and landed at Fpz (forehead), in two steps, with alternating stimulation of the right and left ears. Results: In this study, there was 100% detectability of the Na, Pa, and Nb components and interamplitude Na–Pa. This study compared different electrode leads, and there was no significant difference between the different electrode positions studied for the right and left ears in the studied population. Conclusion: It was concluded that the examination of middle-latency evoked potential is steady and feasible for the studied age group regardless of electrode position.


2021 ◽  
Vol 17 (3) ◽  
pp. 295-301
Author(s):  
D.J. Marlin ◽  
H.P. Martin ◽  
S. Hughes ◽  
J.M. Williams

Stirrups aid the rider to stabilise their lower leg allowing it to be used effectively for communication and in maintaining their position in the saddle. Relatively few studies have investigated stirrup forces and to the best our knowledge no studies have reported stirrup forces in jumping. The aim of the present study was to measure stirrup forces in five showjumping horses ridden by the same professional rider. All horses were in regular training and competition jumping at least 30 cm higher than the fence used for the study. The fence chosen was a 70 cm upright with a pole at the top and a groundline. Right and left stirrup forces were measured using wireless load cells placed between the stirrup leathers and the stirrup. The signals were transmitted and digitised at 100 Hz and synchronised with video from a webcam using an inertial measurement unit. After warming-up, including over jumps, each horse attempted the jump three times from each rein in canter (3 horses left then right rein; 2 horses right then left rein). Mean peak total (sum of left and right) stirrup force for the approach (n=5 strides per horse per jump), take-off and landing phase of the jump was 1,034±110, 1,042±284 and 1,447±256 N (range 905 to 1,815 N), respectively (mean ± standard deviation). There was no significant difference between right or left mean peak stirrup force during approach or take-off, but mean peak force was consistently higher on the right stirrup during the early phase of landing on either the right or left rein (right: 827±320 N; left: 615±336 N; P<0.05). In conclusion, the mean total peak stirrup forces measured in the present study in the same rider jumping five different horses over a 70 cm single upright fence are similar to previous reports of peak stirrup forces in gallop and consistent with observations of asymmetric loading of the saddle and horses’ backs by riders.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 526.1-526
Author(s):  
L. Nacef ◽  
H. Riahi ◽  
Y. Mabrouk ◽  
H. Ferjani ◽  
K. Maatallah ◽  
...  

Background:Hypertension, diabetes, and dyslipidemia are traditional risk factors of cardiac events. Carotid ultrasonography is an available way to detect subclinical atherosclerosis.Objectives:This study aimed to compare the intima-media thickness in RA patients based on their personal cardiovascular (CV) history of hypertension (hypertension), diabetes, and dyslipidemia.Methods:The present study is a prospective study conducted on Tunisian RA patients in the rheumatology department of Mohamed Kassab University Hospital (March and December 2020). The characteristics of the patients and those of the disease were collected.The high-resolution B-mode carotid US measured the IMT, according to American Society of Echocardiography guidelines. The carotid bulb below its bifurcation and the internal and external carotid arteries were evaluated bilaterally with grayscale, spectral, and color Doppler ultrasonography using proprietary software for carotid artery measurements. IMT was measured using the two inner layers of the common carotid artery, and an increased IMT was defined as ≥0.9 mm. A Framingham score was calculated to predict the cardiovascular risk at 10-year.Results:Forty-seven patients were collected, 78.7% of whom were women. The mean age was 52.5 ±11.06 [32-76]. The rheumatoid factor (RF) was positive in 57.8% of cases, and anti-citrullinated peptide antibodies (ACPA) were positive in 62.2% of cases. RA was erosive in 81.6% of cases. Hypertension (hypertension) was present in 14.9% of patients, diabetes in 12.8% of patients, and dyslipidemia in 12.8% of patients. Nine patients were active smokers. The mean IMT in the left common carotid (LCC) was 0.069 ±0.015, in the left internal carotid (LIC) was 0.069 ±0.015, in the left external carotid (LEC) was 0.060 ±0.023. The mean IMT was 0.068 ±0.01 in the right common carotid (RCC), 0.062 ±0.02 in the right internal carotid (RIC), and 0.060 ±0.016 in the right external carotid (REC). The IMT was significantly higher in the left common carotid (LCC) in patients with hypertension (p=0.025). There was no significant difference in the other ultrasound sites (LIC, LEC, RCC, RIC, and REC) according to the presence or absence of hypertension. The IMT was also significantly increased in patients with diabetes at LCC (p=0.017) and RIC (p=0.025). There was no significant difference in the IMT at different ultrasound sites between patients with and without dyslipidemia.Conclusion:Hypertension was significantly associated with the increase in IMT at the LCC level in RA patients. Diabetes had an impact on IMT in LCC and RIC. However, dyslipidemia did not affect the IMT at the different ultrasound sites.References:[1]S. Gunter and al. Arterial wave reflection and subclinical atherosclerosis in rheumatoid arthritis. Clinical and Experimental Rheumatology 2018; 36: Clinical E.xperimental.[2]Aslan and al. Assessment of local carotid stiffness in seronegative and seropositive rheumatoid arthritis. SCANDINAVIAN CARDIOVASCULAR JOURNAL, 2017.[3]Martin I. Wah-Suarez and al, Carotid ultrasound findings in rheumatoid arthritis and control subjects: A case-control study. Int J Rheum Dis. 2018;1–7.[4]Gobbic C and al. Marcadores subclínicos de aterosclerosis y factores de riesgo cardiovascular en artritis temprana. Subclinical markers of atherosclerosis and cardiovascular risk factors in early arthritis marcadores subclínicos de aterosclerose e fatores de risco cardiovascular na artrite precoce.Disclosure of Interests:None declared


Author(s):  
Marthinus J. Kotze ◽  
Kurt-W. Bütow ◽  
Steve A. Olorunju ◽  
Harry F. Kotze

There is a lack of information in comparing the healing rate between the left and right sides of the maxilla and mandible. Osteogenesis of alveolar bone was evaluated with digital radiology by comparing differences in bone density (BD) at different time points within the left and right maxilla and mandible. Alveolar bone defects were created in five healthy Chacma baboons. Standardised x-ray images were acquired over time and the densities of the selected trauma areas were measured pre-operatively, post-operatively and at 3 and 6 weeks post-operatively. Differences in densities were statistically tested. There was no significant difference when the grey scale averages of the combined first and fourth quadrants (right side) and combined second and third quadrants (left side) were compared pre-operatively (t = 0.70), immediately post-operatively (t = 0.34), 3 weeks post-operatively (t = 0.40) and 6 weeks post-operatively (t = 0.66). There was also no significant difference between the values for the first and second quadrants (maxilla) pre-operatively (t = 0.37), immediately post-operatively (t = 0.30), 3 weeks post-operatively (t = 0.30) and 6 weeks post-operatively (t = 0.38); the third and fourth quadrants (mandible) were also not significantly different pre-operatively (t = 0.29), immediately post-operatively (t = 0.69), 3 weeks post-operatively (t = 0.07) and 6 weeks postoperatively (t = 0.06). However, the results showed an increased predisposition of the right side to regenerate faster than the left side and indicated sufficient information to investigate the effect of laterality and preferred side of mastication on the rate of healing and alveolar BD in the maxilla and mandible.


Author(s):  
Chang-Jun Choi, Ha-Sung Kong

This study used the Pathfinder program to evaluate evacuation safety by assuming evacuation training in high school buildings and changing classroom layout. Analysis of the final evacuation requirements for Scenario 2, which currently has a concentration of classrooms on the third floor of the building, showed that Scenario 2 reduced 29.6 seconds to 173.9 seconds compared to Scenario 1's 203.5 seconds. However, the analysis of Scenario 3, in which 10 classrooms and personnel of three grades were placed equally on the left and right sides of the building, showed that the final evacuation requirements were reduced 3.9 seconds to 170.0 seconds compared to Scenario 2, but there was no significant difference. Scenario 3, which has more the efficiency of school year operation by placing classroom layout on the same floor by grade level than Scenario 2, in which more classrooms and students were placed downstairs. In each scenario, an analysis of the final evacuation requirements showed that the evacuation exit T1 on the left side of the building was 28 seconds or more shorter than T3 on the right side of the building. Therefore, it was analyzed that proper classroom layout and ramp facilities in high school buildings ensure evacuation safety


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