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OBJECTIVES@#To explore the relationship between the frequency characteristics and response threshold of auditory steady-state response (ASSR), auditory brainstem response (ABR) and 40 Hz auditory event related potential (40 Hz AERP), and their application values in forensic medicine.@*METHODS@#Thirty volunteers with normal hearing (60 ears) were selected to perform pure tone audiometry (PTA) threshold and ASSR, ABR and 40 Hz AERP response threshold tests in the standard sound insulation shielding room, and the results were statistically analyzed by SPSS 22.0 software.@*RESULTS@#At 0.5 kHz and 1.0 kHz frequencies, the correlation between 40 Hz AERP response threshold and PTA threshold was good, which was better than that of ASSR and ABR response threshold. At 2.0 kHz and 4.0 kHz frequencies, the correlation between ASSR and ABR response thresholds and PTA threshold was good, which was better than that of 40 Hz AERP response threshold.@*CONCLUSIONS@#To evaluate the hearing at 0.5 kHz and 1.0 kHz frequencies, it is recommended to use 40 Hz AERP and ASSR to comprehensively assess the PTA threshold of the subjects. To evaluate the hearing at 2.0 kHz and 4.0 kHz frequencies, ABR and ASSR are recommended to assess the PTA threshold of subjects comprehensively. The combination of ASSR, ABR and 40 Hz AERP can improve the accuracy of hearing function evaluation.
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Humans , Acoustic Stimulation/methods , Audiometry, Evoked Response , Audiometry, Pure-Tone , Auditory Threshold/physiology , Evoked Potentials, Auditory, Brain Stem/physiology , Forensic Medicine , Hearing/physiologyABSTRACT
OBJECTIVE: To evaluate the application value of 40 Hz auditory event related potential(40 Hz AERP) in hearing assessment in workers exposed to noise by observing the consistency between pure tone audiometry(PTA) and 40 Hz AERP. METHODS: A total of 240 ears of 120 workers who exposed to noise with PTA high-frequency hearing threshold > 25 dB were selected as the research subjects using the convenient sampling method. The thresholds of PTA and 40 Hz AERP at different frequencies were investigated. According to the average hearing threshold of PTA language frequency, the workers were divided into normal hearing group and mild-, medium-, medium-severe-, severe-hearing loss groups, and the difference and correlation between the thresholds of 40 Hz auditory potential and PTA were analyzed. RESULTS: The response thresholds of 40 Hz AERP of 0.5, 1.0, 2.0 kHz in ears of normal hearing group, and mild-and moderate-hearing loss groups were higher than the PTA hearing threshold(P<0.01), while the 40 Hz AERP response thresholds of 0.5 kHz in the ears of medium-severe-and severe-hearing loss groups were lower than the hearing thresholds of PTA(P<0.05). The different value of the response threshold of 40 Hz AERP and PTA of 1.0 and 2.0 kHz in ears of normal hearing group was higher than 0.5 kHz(median: 25.0 vs 15.0 dBHL, 30.0 vs 15.0 dBHL, P<0.01). Except for 0.5 and 1.0 kHz of mild-hearing loss group, the different value of the response threshold of 40 Hz AERP and PTA in ears of the other hearing loss groups were lower than that of the normal hearing group(P<0.01). The 40 Hz AERP response threshold was frequency-specific and correlated well with PTA at the same frequency. The correlation coefficients of 0.5, 1.0 and 2.0 kHz were 0.744, 0.732 and 0.665 respectively(P<0.01). CONCLUSION: It is feasible to evaluate PTA in noise-exposed workers using 40 Hz AERP response threshold, but the 40 Hz AERP cannot completely replace PTA. The measurement frequency and the degree of hearing loss should be considered simultaneously.
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Objective The tests of three types of auditory evoked potentials （AEPs） were performed on normal young adults, to understand the frequency characteristics of different testing methods and the relationship between response threshold and pure tone audiometry threshold of different methods, and to discuss the forensic value of 3 types of AEPs to evaluate hearing function. Methods Twenty normal young adults were selected, their standard pure tone audiometry threshold, short-term pure tone audiometry threshold and the response threshold of 3 types of AEPs （tone burst-auditory brainstem response, 40 Hz auditory event-related potential and slow vertex response） at 0.5 kHz, 1.0 kHz, 2.0 kHz and 4.0 kHz were recorded. The relationship between the response threshold and standard pure tone audiometry threshold, short-term pure tone audiometry threshold of 3 types of AEPs at different frequencies as well as the differences between different types of AEPs were analyzed. Results The short-term pure tone audiometry threshold was higher than the standard pure tone audiometry threshold at each frequency. The response threshold and standard pure tone audiometry threshold of the 3 types of AEPs all had a certain correlation, and the response threshold of the 3 types of AEPs was higher than short-term pure tone audiometry threshold and standard pure tone audiometry threshold at each frequency. The differences in the differences between the response threshold and standard pure tone audiometry threshold of the 3 types of AEPs at different frequencies had statistical significance. Linear regression mathematical models were established to infer the standard pure tone audiometry threshold （hearing level） from response threshold （sound pressure level） of 3 types of AEPs of normal young adults. Conclusion When using response threshold of different types of AEPs to estimate pure tone audiometry threshold, conversion and correction are needed. Combined use of different types of AEPs could improve the accuracy of hearing function evaluation.
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Humans , Young Adult , Audiometry, Evoked Response , Audiometry, Pure-Tone , Auditory Threshold , Evoked Potentials, Auditory , Evoked Potentials, Auditory, Brain Stem , HearingABSTRACT
Objective To investigate the characteristics of auditory event-related potentials(AERP) mismatch negativity and P300 in presbycusis patients.Methods Auditory event-related potentials were recorded from 20 presbycusis patients, 20 normal hearing elderly subjects and 20 normal young volunteers(the control group) in the Oddball stimulus paradigm.Mismatch negativity(MMN) was tested under the status of reading.P300 was tested under the status of concentrating.The latencies and amplitudes of 3 groups were compared.Results The latency of MMN in the presbycusis patient group(187.38±29.63ms) was significantly longer than those of the normal hearing older group(160.10±23.21±ms)and the control group(148.22±19.30 ms)(P0.05).The latency of P300 in the presbycusis patient group (369.83±27.09 ms) was significantly longer than those of the normal hearing older group(332.89±25.60 ms)and the control group(318.51±22.32ms)(P0.05).Conclusion The presbycusis patients show some central auditory processing dysfunction and cognitive impairment.MMN and P300 might be used as objective methods for evaluating central auditory processing and cognitive function in presbycusis patients.
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Objective To compare the latency and amplitude of normal subject's auditory event -related po‐tentials(AERP) via P300 evoked by same target stimulation and different intensitve non target stimulation ,and to explore the appropriate intensity of target and nontarget stimulus which evoke typical P300 at the same frequency . Methods A total of 20 normal young volunteers were induced in this study .Each subject received 3 AERP tests , respectively by the same tone burst target stimulus(60 dB nHL ,1 kHz) and different intensity levels for the non target stimulus(50 ,65 ,70 dB nHL ,and 1 kHz) ,and the latency and amplitude of 3 group's P300 were compared . Results In all cases ,P300 was successfully induced .The latencies of 3 group's P300 were 316 .25 ± 21 .16 ms , 320 .83 ± 22 .64 ms ,318 .44 ± 25 .82 ms (P>0 .05) ,respectively and the amplitudes of 3 group's P300 were 5 .02 ± 2 .04 μV ,7 .42 ± 2 .58 μV ,3 .54 ± 2 .23 μV (P<0 .01) ,respectively .The amplitude of the moderate intensity group was greater than the high intensity group and low intensity group ,and the amplitude differences were not statistical‐ly significant between the high and the low intensity groups .Conclusion Different intensity levels of nontarget stim‐ulus do not affect the latency of P300 ,but significantly affect the amplitude .Along with the decreasing of the inten‐sity difference of target and nontarget stimula ,the P300 amplitude raise gradually .A typical P300 is induced at the same frequency when the target stimuli and non target stimuli are 60 dB nHL and 65 dB nHL respectively .
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Objective To study the changes of hearing function and cochlear morphology on diffuse brain in-jury model in rat .Methods One hundred and fifty SD rats with normal hearing were randomly divided into five groups ,each group consisted of 30 SD rats ,including a control group and four experimental groups which endured diffuse brain injury(DBI) from one to four weeks .Diffuse brain injury model of rats were established ,then ABR , 40 Hz AERP and ASSR examination ,light microscopy ,electron microscopy were used to evaluate the change of hearing function and morphology .Results The difference of ABR ,40 Hz AERP and ASSR thresholds between the experimental and the normal control group were significant (P<0 .05) .The thresholds of ABR ,40HzAERP and AS-SR were increased in the first week of DBI ,then the threshold continuously increased in the second and third week , at last the threshold decreased in the fourth week .The results under scaning electron microscope demonstrated that the ciliums of the majority of outer hair cells lodged in the first week of DBI .The results under transmission electron microscope showed that in the first week of DBI ,there were edema and denuration of mitochondrial ,mitochondrial cristaes were obscured or disappeared .The changes were deteriorate in the second and third week ,whereas the changes were mitigatal in the fourth week .Conclusion Cochlear morphology and hearing damage were observed in diffuse brain injury model of rats .
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Autism is a pervasive developmental disorder characterized by deficits in socialization, communication, and adaptive functioning. To investigate its neurophysiology, lots of measures have been used. In the past twenty years, due to its evaluation function in the central auditory processing and recognition, auditory event related potential has been implemented in autism more and more generally.
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Objective To study the effect of different attention states on auditory ERP and EEG power in normal subjects. Methods In three different states such as passive attention,active attention with target counting and active attention without target counting,EEG were recorded using oddball paradigm in 8 normal subjects while the test tones were presented;Then the peak-peak amplitude and latency of ERP were evaluated and the EEG power spectra were observed. Results The condition of active attention with target counting resulted in the smallest peak-peak amplitude of P 2-N 1 and the largest one of P 3-N 2,and it led to the increment of EEG power at the frequency of 10Hz,while the latencies did not differ among the three different attention states. Conclusion Reduced P 2-N 1 amplitude and increased P 3-N 2 amplitude reflected the allocation changes of attention resource in different states,and increased EEG power reflected more energy consumption in the process of recognition and memory,but the latency was relatively stable and not affected significantly by subject's attention condition.
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OBJECTIVES: This study was carried out to investigate the clinical availability of topographic auditory event related potential P300 as a biological marker in children with attention deficit hyperactivity disorder(ADHD). METHODS: The subjects were composed of children with ADHD(n=22:16 boys, 6 girl s:mean age=89.8+/-17.1months) and normal controls(n=20:12 boys, 8 girls:mean age=90.6+/-16.8months). Topographic auditory event related potential was measured by "oddball paradigm", and the latencies and amplitudes of P300 of both groups were determined by Global Field Power Measurement. After 8 weeks treatment with methylphenidate, P300 of ADHD children were also measured. RESULTS: Both P300 latency and amplitude were not different between ADHD children after treatment and normal controls, but significantly different between ADHD children before treatment and normal controls, and between before and after treatment of ADHD children. CONCLUSIONS: The results implicate that the latency and amplitude of P300 may be considered as state markers of ADHD.
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Child , Female , Humans , Attention Deficit Disorder with Hyperactivity , Biomarkers , Evoked Potentials , MethylphenidateABSTRACT
Objective To study the neuroelectrophysiological responsibility, mechanism and clinical application of auditory event-related potential (AERP) generated in bilateral auditory centers with ipsilateral and contralateral recordings. Methods 14 normal young adults were served as subjects. AERPs, including the responsibility, latencies, amplitudes and waveforms, were simultaneously recorded on ipsilateral and contralateral vertexes and analyzed. Results The latencies and amplitudes of AERPs did not show significicant difference statislically between ipsilateral and contralateral vertexes recordings. However, the responsibility of AERP recorded on ipsilateral vertex was more satisfied than that on contralateral vertex, which exhibited smoothing waves, discriminative wave peaks and little hetero-wave. Conclusion The origins of AERP in bilateral auditory centers were essentially symmetrical. Nevertheless, the responsibility of AERP recorded on ipsilateral vertex was more satisfied than that on contralateral vertex, which was related to the components of auditory subcortex, transmission of auditory nerve to bilateral centers and the contralateral inhibiting effect of medial olivo-cochlear system. The effects of multi-generation and multi-component of AERPs on the clinical application should be considered.
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OBJECTIVES: The authors studied the effects of cigarette smoking on the cognitive function with topographic mapping of auditory event-related potential P300. METHODS: The subjects, 24 smokers and 14 nonsmokers, were assessed in the latencies and amplitudes of topographic auditory event-related potential P300 determined by Global Field Power Measurement. RESULTS: 1) There were significant differences of P300 latencies between smokers and controls artier smoking(ANOVAL F=10.45, P=0.0026). 2) There were no significant differences of P300 amplitude but a trend was present between smokers and nonsmokers after smoking(ANOVAL F=3.77, P=0.06). 3) There were no significant differences of difference between amplitude in maximal point and amplitude in minimal point but a trend was present between smokers and nonsmokers artier smoking(ANOVAL F=3.68, P=0.063). 4) There were no significant differences of maximal point in X-axis and in Y-axis, minimal point in X-axis and in Y-axis of P300 between smokers and nonsmokers artier smoking. CONCLUSIONS: These results support that auditory event-related potential P300 change by cigarrete smoking is indicative of enhanced cognitive function.
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Evoked Potentials , Smoke , Smoking , Tobacco ProductsABSTRACT
Objective:To explore auditory event-related P300 in children with behavior problems. Methods: 40 children with behavior problems were screened out from a ample of pupils by CBCL and CRT-C 2. The control group was selected from the others matched by age and gender, the rate of case/control was 1:2. The study and control group were assessed by auditory event-related P300 elicited by pure tone stimuli using the oddball paradigm.Results:(1) There was no significant difference in P300 between study and control groups; (2) The P300 latency of mixed problem group were significantly longer than those of controls. (3) The P300 amplitude were significantly negatively correlated with the CBCL score.Conclusion:It is suggested cognitive function deficit of severe behavior problem children.