Normal Young People Research Articles

Study on Self-Monitoring Method of Ankle Impedance

Abstract Objective The aim of the study was to analyze the self-monitoring ankle impedance measuring instrument for patients with heart failure and to evaluate the degree of ankle impedance variation in normal young people for three days. Methods We developed a portable impedance measuring instrument based on AD5940 chip of ADI. The circuit composed of programmable alternating current (AC) voltage generator, digital signal processor, microcontroller, and related peripheral circuits. The four-line body impedance analysis measurement method was used, which was powered by two 1.5-V batteries, and a frequency of 50 kHz was selected to improve the measurement accuracy. The bioimpedance of the human body can be measured in the range of 0 to 2,000 Ω, and the phase range is –180 to + 180 degrees, both of which are accurate to two decimal places. Ten normal young volunteers were included, with an average age of 24.5 ± 1.3 years. The electrical impedance of the right ankle was measured in the sitting position, the supine position, and the standing position. Each posture was measured three times, and the variation of the ankle impedance was observed for three days at the same time point. Results There was no significant difference in ankle impedance between the three positions of 10 volunteers in this group during the three days. The mean difference between the mean groups ranged from 6.14 to 9.53%, and the maximum difference was 9.53%. There was no significant correlation between ankle impedance and BMI in the three positions. Conclusion Although there are some changes in the ankle impedance measured by the self-developed impedance tester within three days, it can still monitor the ankle impedance of normal young people relatively stably. This impedance meter may be used for home monitoring of ankle impedance in patients with heart failure.

Depression and anxiety among first-year students at Hanoi Medical University, academic year 2022-2023

Background: Depression and anxiety are common mental health problems in medical students worldwide. This study aims to estimate the prevalence of self-reported depression, and anxiety and to identify associated risk factors among first-year medical students at Hanoi Medical University. Method: A cross-sectional study was conducted from October 2022 to January 2023 at Hanoi Medical University using the DASS-21 scale. Results: Among 353 participants, we found that (i) the prevalence of self-reported depression and anxiety was 34.8% and 69.7%, respectively; (ii) times of exercise per week, hours of sleep per night, and participation in clubs are some factors associated with self-reported depression and anxiety. Conclusion: The prevalence of self-reported depression and anxiety in first-year medical students is notably higher than normal young people in Vietnam. Our study will provide foundations and references for future studies to explore further impacts of the academic environment on first-year medical students.

Pre-coronavirus disease 2019 brain structure might be associated with social anxiety alterations during the pandemic.

Pre-coronavirus disease 2019 brain structure might be associated with social anxiety alterations during the pandemic.

Brain network mechanism on cognitive control task in the elderly with brain aging: A functional near infrared spectroscopy study.

To study the brain network mechanism of cognitive control in the elderly with brain aging. 21 normal young people and 20 elderly people were included in this study. Mini-mental State Examination and functional near-infrared spectroscopy (fNIRS) synchronous judgment test (including forward tests and reverse judgment tests) were performed on all subjects. To observe and compare differences in brain region activation and brain functional connectivity between subjects and forward and reverse trials by recording functional connectivity (FC) in different task paradigms and calculating bilateral prefrontal and primary motor cortical (PMC) areas. In the forward and reverse judgment tests, the reaction time of the elderly group was significantly longer than the young group (P < 0.05), and there was no significant difference in the correct rate. In the homologous regions of interest (ROI) data, the FC of PMC and prefrontal cortex (PFC) in the elderly group was significantly decreased (P < 0.05). In the heterologous ROI data, except for left primary motor cortex (LPMC)-left prefrontal cortex (LPFC), the other PMC and PFC of the elderly group were significantly lower than the young group (P < 0.05) while processing the forward judgment test. However, the heterologous ROI data of LPMC-right prefrontal cortex (RPFC), LPMC-LPFC and RPFC-LPFC in the elderly group were significantly lower than the young group (P < 0.05) while processing the reverse judgment test. The results suggest that brain aging affected degeneration of whole brain function, which reduce the speed of information processing and form a brain network functional connection mode different from that of young people.

Objective Assessment of Hyposmia in Alzheimer's Disease From Image and Behavior by Combining Pleasant Odor With Unpleasant Odor.

Background: Olfactory functional magnetic resonance imaging (fMRI) of responses to a pleasant odor (PO) (lavender) can objectively evaluate olfactory dysfunction in Alzheimer's disease (AD) patients. The brain responses to a PO and unpleasant odor (UPO) were shown to differ in normal young people. Whether AD patients with olfactory dysfunction have the same brain response is not yet known.Objective: Our aim was to explore whether olfactory fMRI with both a PO and UPO can provide more information regarding olfactory impairment in AD than a PO alone.Methods: Twenty-five normal controls (NC), 26 individuals with mild cognitive impairment (MCI), and 22 AD patients underwent olfactory fMRI with lavender and pyridine odorants at three concentrations (0.10, 0.33, and 1.00%) with a 3.0-T MRI scanner.Results: There were no differences in the number of activated voxels in the primary olfactory cortex (POC) between PO and UPO conditions in the NC, MCI, and AD groups (SPM, paired t-test, uncorrected p < 0.001, extent threshold = 70). In the right inferior frontal gyrus, orbital part (F3O), the number of activated voxels was greater with the UPO than with the PO in the NC group (SPM, paired t-test, uncorrected p < 0.001, extent threshold = 70), but there were no differences in the MCI and AD groups. Regardless of PO or UPO conditions, there were significant differences in the number of activated voxels in the POC among the NC, MCI, and AD groups. With increasing odor concentration, the number of activated voxels in the POC decreased in the NC group but increased in the AD group. When 0.10% UPO was presented, the NC group (21/25) showed a lower breathing amplitude and shorter inhalation time, whereas the AD patients (0/22) did not show such changes in breathing.Conclusions: After PO and UPO inhalation, brain activation and respiratory behavior in AD patients were significantly different than in NC patients. Therefore, olfactory fMRI using both PO and UPO stimulation, compared with PO stimulation only, can provide more objective information regarding hyposmia associated with AD based on imaging and behavior.

Finite element mechanics analysis of lumbar spine with normal and varying degrees of herniated lesions under different working conditions and material properties

This paper has completed the three-dimensional reconstruction of normal young people’s L4–L5 lumbar spine integration model and the integrated model of different degree of disk herniation. On the basis of the reconstruction model, add meshing and set the corresponding material properties of each component, and apply different concentrated forces and boundary conditions to the established finite element model to simulate different working conditions, and then obtain the corresponding nephogram of deformation, displacement and stress of the 3D model. By analyzing the biomechanical characteristics of the model, the validity of the constructed three-dimensional model was verified.

Cone-beam CT evaluation of the Monson's spherical radius of young adults in Guangdong

Objective: To measure and analyze the spherical radius of Monson of normal young people in Guangdong province using cone-beam CT (CBCT), and to establish a personalized measurement method of the spherical radius of Monson to provide a reference for clinical application of Monson spherical radius in occlusal reconstruction. Methods: Sixty healthy young adults from physical examination population at Stomatology Hospital of Guangzhou Medical University [30 males and 30 females, aged (22.1±2.0) years 18-26 years) were recruited, and their CBCT were taken. Three-dimensional reconstruction of CBCT data was carried out, and the reconstructed models were fixed, traced and measured. The difference of Monson spherical radius between male and female was compared by using a single sample t-test. Results: The Monson spherical radius was (100.72±4.89) mm. The Monson spherical radius of male and female were (103.48±4.19) mm and (97.97±3.93) mm respectively. The difference between male and female was statistically significant (P<0.01). Conclusions: CBCT can be used to accurately measure the spherical radius of Monson and can be used as a reference for reconstruction of occlusal plane.

Study on normal reference range of smooth tracking gain for healthy young people

Objective:Analysis of normal reference value of smooth pursuit test for normal young people. Method:Thirty normal young volunteers were tested by Synapsys videonystagmography. The maximum horizontal tracking angle was 30 °, the vertical maximum tracking angle was 20°, and the frequency was 0.30 Hz, 0.45 Hz and 0.60 Hz, respectively， and the gain under different conditions is used as the observation index. Result:When the frequency is 0.3 Hz, 0.45 Hz, 0.60 Hz, the left and right horizontal gain is 0.92±0.07/0.93±0.07, 0.87±0.08/0.88±0.11, 0.79±0.11/0.78±0.13, respectively, and the asymmetry of left/right gain is 0.021±0.017, 0.031±0.026, 0.037±0.040; the up and down vertical gain is 0.82±0.16/0.80±0.16, 0.78±0.17/0.72±0.15, 0.68±0.20/0.61±0.15, and the asymmetry of the upper/lower gain is 0.046±0.045, 0.069±0.058, 0.109±0.076. Comparing and analyzing the paired left and right gain values of the three frequencies by paired t test, the differences were not statistically significant （P>0.05）. Paired t -test of gain value for different frequency of up and down stationary tracking, the difference was not statistically significant at 0.30 Hz（P>0.05）, but the gain at 0.45 Hz and 0.60 Hz has significant difference（P<0.05）. Comparing the gains of different frequencies in the same direction, the differences in analysis of variance were statistically significant（P<0.05）. Conclusion:The gain value of smooth pursuit test for normal young people can be affected by tracking frequency and direction. At the same frequency, the left/right tracking of 3 frequencies and the up/down tracking gain values of 0.30 Hz are symmetrical, but at 0.45 Hz and 0.6 Hz, the up tracking gain is greater than the down tracking gain, and the gain value in the same direction gradually decreases with the increase of frequency, is the clinical smooth pursuit test is mainly based on 0.30 Hz.

Analysis of broadband sinusoidal harmonic acceleration test results for normal young people

Objective: We tested more frequency (0.01-3.0 Hz) of the sinusoidal harmonic acceleration test(SHAT) by the NKI rotation chair, aimed to analyze the results of the normal youth. Methods: Fifty normal young people were tested with sinusoidal harmonic acceleration by NKI rotation chair. Including 24 men and 26 women, aged from 20 to 40 years old, with median age of 27 years, with no vestibular dysfunction participated in the present study. All the volunteers accepted the sinusoidal harmonic acceleration test by the NKI rotation chair, the frequency included 0.01 Hz, 0.02 Hz, 0.03 Hz, 0.05 Hz, 0.1 Hz, 0.2 Hz, 0.3 Hz, 0.6 Hz, 1.0 Hz, 1.5 Hz, 2.0 Hz, 3.0 Hz. Taken the gain, phase, and asymmetry as the parameters, the trait of each frequency was analysed. Results: From 0.01 Hz to 1.5 Hz, the gain increased close to 1 gradually, and with fluctuates slightly at the 2.0 Hz and 3.0 Hz frequencies. The phase decreased as frequencies increased close to 0 at 0.3 Hz. The frequency above 0.6 Hz presented negative. Asymmetric values were distributed on both positive and negative sides at each frequency and were different from each other, both values were less than 20%. Conclusion: Broadband SHAT can accurately assess the horizontal semicircular canal function at different frequencies in a wider frequency range, and objectively, reflect the physiological function of the horizontal semicircular canal, and expand the clinical value of traditional SHAT.

Frequency properties of bone-conducted vibration and sound-induced ocular evoked myogenic potential

Objective: The present study was to compare the frequency characteristics of bone- conducted vibration (BCV) and air-conducted sound-induced ocular vestibular evoked myogenic potential(oVEMP) with different stimulation settings, so as to select an optimal setting. Methods: Bruel and Kjaer artificial mastoid was used to calibrate bone vibrator, the mini-shaker. The outputspectrum and transient waveform were recorded when the input frequency was set at different frequencies and data were further analyzed to get the peake quivalent force level value of the output vibration. oVEMP was recorded as we previously reported with normal young adults. Response prevalence, latency, wave interval, amplitude, amplitude ratio, and bilateral amplitude asymmetry ratio were recorded and analyzed. SPSS 24.0 software was used for statistical analysis. Results: Output peak equivalent force level increased as the intensity of primary input stimulation increased at certain frequency,while it decreased as the frequency of primary input stimulation increased at certain intensity. Peak equivalent force level of 500 Hz tone burst (1-2-1) input stimulation was greatest as 139.8 dB when using mini-shaker for vibration stimulation,even greater when using bone conductor B-71.Twenty subjects were elicited with normal oVEMP with N1 and P1 waves in both ears using air-conducted stimulation or bone-conducted vibration.The response rate in these subjects was 95% and 100% respectively. The latency of N1 was (11.33±1.35) ms and (10.14±0.38) ms, latency of P1 was (16.24±1.56) ms and (15.65±1.19) ms, interval N1-P1 was (4.59±1.26) ms and (5.55±0.81) ms, symmetry coefficient was 12.22%[5.50%,21.85%] and 8.74%[3.37%,14.08%], amplitude was 3.07[2.05,4.43] μV and 3.07[2.05,4.43] μV in sound and bone conducted vibration group, respectively. The latency of N1, latency of P1, interval N1-P1, symmetry coefficient and n1-P1 amplitude of BC-oVEMP were different statistically (all P<0.05). Conclusions: 500 Hz 45 dB input stimulation setting is the optimal parameter for BC-oVEMP. BC-oVEMP can be recorded simply, safely and quickly in normal young people, thus it is a clinically practical way of measuring utricular function.

Frequency properties of bone-conducted vibration and sound-induced ocular evoked myogenic potential

Objective: The present study was to compare the frequency characteristics of bone- conducted vibration (BCV) and air-conducted sound-induced ocular vestibular evoked myogenic potential(oVEMP) with different stimulation settings, so as to select an optimal setting. Methods: Bruel and Kjaer artificial mastoid was used to calibrate bone vibrator, the mini-shaker. The outputspectrum and transient waveform were recorded when the input frequency was set at different frequencies and data were further analyzed to get the peake quivalent force level value of the output vibration. oVEMP was recorded as we previously reported with normal young adults. Response prevalence, latency, wave interval, amplitude, amplitude ratio, and bilateral amplitude asymmetry ratio were recorded and analyzed. SPSS 24.0 software was used for statistical analysis. Results: Output peak equivalent force level increased as the intensity of primary input stimulation increased at certain frequency,while it decreased as the frequency of primary input stimulation increased at certain intensity. Peak equivalent force level of 500 Hz tone burst (1-2-1) input stimulation was greatest as 139.8 dB when using mini-shaker for vibration stimulation,even greater when using bone conductor B-71.Twenty subjects were elicited with normal oVEMP with N1 and P1 waves in both ears using air-conducted stimulation or bone-conducted vibration.The response rate in these subjects was 95% and 100% respectively. The latency of N1 was (11.33±1.35) ms and (10.14±0.38) ms, latency of P1 was (16.24±1.56) ms and (15.65±1.19) ms, interval N1-P1 was (4.59±1.26) ms and (5.55±0.81) ms, symmetry coefficient was 12.22%[5.50%,21.85%] and 8.74%[3.37%,14.08%], amplitude was 3.07[2.05,4.43] μV and 3.07[2.05,4.43] μV in sound and bone conducted vibration group, respectively. The latency of N1, latency of P1, interval N1-P1, symmetry coefficient and n1-P1 amplitude of BC-oVEMP were different statistically (all P<0.05). Conclusions: 500 Hz 45 dB input stimulation setting is the optimal parameter for BC-oVEMP. BC-oVEMP can be recorded simply, safely and quickly in normal young people, thus it is a clinically practical way of measuring utricular function.

EHomeSeniors Dataset: An Infrared Thermal Sensor Dataset for Automatic Fall Detection Research.

Automatic fall detection is a very active research area, which has grown explosively since the 2010s, especially focused on elderly care. Rapid detection of falls favors early awareness from the injured person, reducing a series of negative consequences in the health of the elderly. Currently, there are several fall detection systems (FDSs), mostly based on predictive and machine-learning approaches. These algorithms are based on different data sources, such as wearable devices, ambient-based sensors, or vision/camera-based approaches. While wearable devices like inertial measurement units (IMUs) and smartphones entail a dependence on their use, most image-based devices like Kinect sensors generate video recordings, which may affect the privacy of the user. Regardless of the device used, most of these FDSs have been tested only in controlled laboratory environments, and there are still no mass commercial FDS. The latter is partly due to the impossibility of counting, for ethical reasons, with datasets generated by falls of real older adults. All public datasets generated in laboratory are performed by young people, without considering the differences in acceleration and falling features of older adults. Given the above, this article presents the eHomeSeniors dataset, a new public dataset which is innovative in at least three aspects: first, it collects data from two different privacy-friendly infrared thermal sensors; second, it is constructed by two types of volunteers: normal young people (as usual) and performing artists, with the latter group assisted by a physiotherapist to emulate the real fall conditions of older adults; and third, the types of falls selected are the result of a thorough literature review.

Effect of modified body position on cVEMP in normal young people

Objective: To observe the effect of modified body position on cervical vestibular evoked myogenic potential(cVEMP) in normal young people. Method: Thirty normal young people were selected as subjects. CVEMP test was performed by supine head position and sitting submandibular lower body position respectively. The cVEMP examination results were observed and compared. Result: The elicitation rate of the two kinds of position of cVEMP were 100%. There was no significant difference in P1 latency, N2 latency, amplitude and asymmetry ratio. Different body position comfort VAS score, submandibular pressure of sitting position was better than supine head up position(P<0.05). Conclusion: Submandibular pressure of sitting position has no effect on the results of cVEMP examination, and the subjects are more comfortable, and can be used for old age and inability to cooperate with supine head up position.

Standardized Lycium chinense fruit extract enhances attention and cognitive function in healthy young people by a double-blind, randomized, placebo-controlled, crossover trial.

Background:Lycium chinense fruit (LCF) is widely distributed in East Asia that has been used traditionally for antiaging purposes. This study was performed to examine the effects of LCF on attention and cognitive function in healthy young people.Materials and Methods:An 11-week, double-blind, randomized, placebo-controlled, crossover trial of 74 patients was conducted and its data were collected on Kyung-Hee University Korean Medical Hospital, Seoul, Korea. In crossover treatment, LCF or placebo was administered three times a day, total 3600 mg as two capsules of 600 mg once for 4 weeks with 3-week washout each. The computerized neurocognitive function test (CNT), the Korean version of the attention-deficit/hyperactivity disorder rating scale-IV, the clinical global impression rating scale, and the Frankfurt attention inventory (FAIR) for two groups were conducted 0 week before and 4 week, 11 week after the experiment, and significant mean changes of these tests for within group or two groups were measured by paired t-test or unpaired t-test.Results:The administration of LCF or placebo crossover for 8 weeks in healthy young people presented significant improvement in the verbal learning test, digit span forward test, digit span backward test, auditory continuous performance task of CNT, and FAIR-performance value compared with the placebo group (each group n = 43, P < 0.05).Conclusion:Thus, the consumption of LCF might be beneficial to increase learning and memory through attention and cognitive enhancing effect in normal young people, at an average age of 18 years of age.

The analysis of event-related potentials in normal brain aging based on N-back cognitive tasks

The purpose of this study is to investigate the change of the whole brain event-related potentials(P300) in normal brain aging based on N-back cognitive tasks. The P300 of 15 normal young people and 10 normal old people were evaluated based on N-back cognitive tasks and analyzed. The results showed that the P300 latency of old people was longer in whole brain than young people, and amplitude was increased in the frontal-central region, while significantly increased in the pre-frontal region in the same load cognitive tasks. With the cognitive task load increasing, the amplitude of old people in high-load task was higher in the whole brain than that in low-load task, mainly in in the frontal region, but the difference was not statistically significant. The latency in the high-load task was shorter in the frontal-central region of right brain than the low-load task, and the difference was statistically significant. Thus, P300 showed that the normal brain aging process is mainly reflected in the pre-frontal region, and the high-load cognitive task could better reflect the change of brain function compared with the low-load cognitive task. The finding is of revelatory meaning for diagnosis of early dementia in patients.

Variables that Predict Affirmative Responses to the Item If God Told Me to Kill I Would Do it in His Name: Implications for Radical Religious Behaviours

Groups of people who feel sanctioned by God or some equivalent perceived Deity to kill other groups of people who are considered external to the group sometimes constitute armies that eliminate others because they are different. Multiple regression was employed to discern which items from the Personal Philosophy Inventory administered to over 1,200 first year university students over 11 years predicted an affirmative response to the item “If God told me to kill I would do it in His name”. About 7% of the population answered “yes” to this item. Affirmative responders also stated that: they were “special agents of God”, people should be guided to ensure spiritual development and they went to church weekly. They also believed a sign would be given when a tough decision was to be made. Individuals who stated they would kill in God’s name endorsed more traditional religious beliefs than exotic beliefs. The consistency of the pattern over time for this population of normal young people living in an indentified democratic country suggested a potential trait (that if applied over large populations) might produce theme-congruent behaviors. Knowing the characteristics of individuals who respond in this manner might facilitate the development of strategies to reduce the dangerous applications of these beliefs and their recruitment by extremists groups

Determination of normal reference value of pyrrole adducts in urine in young people in a university in Shandong, China

To determine the normal reference value of pyrrole adducts in urine in young people in a university in Shandong, China, and to provide a reliable basis for the clinical diagnosis of n-hexane poisoning. A total of 240 college students were randomly selected. After excluding 32 ineligible students, 208 subjects were included in this study, consisting of 104 males and 104 females, with a mean age of 21?3 years (range: 18 to 24 years). Morning urine was collected from each subject. The content of pyrrole adducts was determined by chromatometry. The content of pyrrole adducts in both male and female obeyed a positively skewed distribution. The median level of pyrrole adducts in male subjects was 0.88 nmol/ml, and the reference value was 0.14-3.92 nmol/ml. The median level of pyrrole adducts in female subjects was 0.93 nmol/ ml, and the reference value was 0.09-3.27 nmol/ml. Student's t test identified no statistical difference in pyrrole adduct level between male and female subjects (t=0.15, P>0.05). The median level of pyrrole adducts in normal young people is 0.91 nmol/ml, and the reference value is 0.11-3.95 nmol/ml.

The effects of Chinese traditional feeding habits on the eating disorders and the psychological analysis

To investigate the impact of Chinese parents' traditional feeding habits on the development of their children's eating disorders, 35 patients suffering eating disorders and a randomly selected 35 normal young people as the control group were studied in this project. A force-feeding score graph was designed, and the 2 groups and their parents were asked to rate their force-feeding scores. The scores of the patients with eating disorders and the scores of their parents are significantly higher than those of the control group (P<0.01; P<0.01). The scores of the children in the two groups are significantly higher than those of the parents' respectively (P<0.01, P<0.01). Our study suggests that the Chinese traditional feeding habits have significant impact on the development of eating disorders.

Gender differences in hand stability of normal young people assessed at low force levels

To examine gender differences in hand stability, finger position and force holding tasks at low force levels were conducted with 30 male and 30 female young adults. Total fluctuation was defined as the standard deviation of measured data and fluctuation and the 10-Hz component of the physiological tremor were compared between maleand female subjects. In all tasks, the total fluctuation and the 10-Hz tremor were significantly larger in male subjects than females. On average, the fluctuation was 1.3 times larger and the 10-Hz tremor was 1.6 times larger. The results of this study suggest that women have superior hand stability compared with men at low force levels. Finger length, maximal voluntary contraction and surface electromyography were also measured and factors related to gender differences in hand stability are discussed. Statement of Relevance: Hand stability is crucial for precise manual operations. This study demonstrated gender differences in hand steadiness at low force levels. Though hand dexterity cannot be explained only by hand stability, the results of thisstudy are useful not only for occupational aptitude tests but also for neuropsychological tests.

Elicitation of mismatch negativity and its influence from stimuli deviant in the healthy youth

To work out the elicitation plan, obtain the mismatch negativity (MMN) and get out the laboratory normal value as well as to study the influence to MMN from the deviation of auditory stimuli. Hearing test of the tone burst stimulation was performed on 21 healthy young volunteers according to oddball stimulation sequence. Each subject was performed two kinds of auditory stimuli including frequency deviant stimuli and intensity deviant stimuli, and of each one included three series of stimulation. MMN was gained by subtracting the ERP of deviant stimuli from the ERP of standard stimuli. The latency and amplitude of each MMN were recorded, and then the effect of the deviant extent for MMN was analyzed. By this setup the MMN of normal young people was recorded and normal value of latency and amplitude of MMN were got. In the group of frequency deviant stimuli, the MMN latency [(155.81 +/- 29.08) ms], if the frequency was up to 2000 Hz, was shorter than that when the frequency deviance was 1000 Hz [(182.89 +/- 45.85) ms, (183.32 +/- 43.33) ms] (P = 0.033, 0.030); when the deviant extent were the same, the latency had no obvious difference if changing the frequency of the standard and deviant stimuli (P = 0.973); the MMN amplitude of three groups [(3.85 +/- 2.22) microV, (2.90 +/- 2.05) microV, (2.66 +/- 2.12) microV] had no obvious difference among them (P > 0.05). In the group of intensity deviant stimuli, the MMN latency [(157.04 +/- 34.87) ms], if the frequency was up to 20 dB, was shorter (P = 0.025, 0.017) than that when the intensity deviance was 10 dB [(184.46 +/- 38.05) ms, (186.24 +/- 42.36) ms]. When the deviant extent were the same, the latency had no obvious difference (P = 0.882) if changing the intensity of the standard and deviant stimuli but only group 4 and group 6 [(3.41 +/- 1.64) microV, (2.37 +/- 1.47) microV] were different in evidence (P = 0.031) while the others had no obvious difference (P = 0.524, 0.122). MMN was only related to the difference between standard stimuli and deviant stimuli, but there was no relationship between MMN and the notice, which indicate that MMN could objectively reflect the capability of brain to detect the change of stimuli. MMN is the representation of brain high-level sensory function.