Exploring the Differences Between an Immature and a Mature Human Auditory System Through Auditory Late Responses in Quiet and in Noise

Many previous studies examining developmental trends in P3 amplitude or latency have used a two-stimulus (standard and target) oddball paradigm. Fewer studies exist using the novelty oddball paradigm, a three-tone (standard, target, and novel) paradigm. In this study with 204 typically developing participants aged 7-25 years, the influence of participant traits-age and sex-on the developmental trends of P3 peak-to-peak amplitude and latency were examined. Additionally, interactions between the three tones of the novelty oddball paradigm and scalp sites on P3 amplitude and latency were evaluated. While previous studies using baseline-to-peak measures have shown smaller P3 amplitude in children compared with adults, this study, using peak-to-peak measures (P3 minus N2 amplitude), found the opposite effect with children having larger P3 amplitudes than adults. This finding is explained by further analyses of N2, representing discrimination. N2 baseline-to-peak amplitude significantly predicted P3 baseline-to-peak amplitude; a mediation effect such that as N2 becomes less negative, P3 becomes larger. Regression analyses revealed that developmental trends of the P3 amplitude were primarily linear, but trends in P3 latency were mostly non-linear. Sex differences were observed, although limited to latency measures. Results from ancovas found significant interactions between the three tones and between frontal (Fz) and parietal (Pz) sites, with larger P3 amplitude during target and novel tones at Pz than Fz, and larger amplitudes during frequent tones at Fz than Pz. These findings highlight the importance of considering more than P3 amplitude in understanding developmental trends in cognitive processing during oddball paradigms.

Age-changed normative auditory event-related potential value in children in Taiwan

To examine the differences in auditory evoked cortical responses that may underlie the tendency of some people to perceive tinnitus. The study hypothesis is that the mean ALR and P300 amplitudes in normal hearing adults who perceive temporary tinnitus after exposure to sustained silence will be larger than the mean ALR and P300 amplitudes in normal hearing adults who do not perceive temporary tinnitus after exposure to sustained silence. This was a prospective cross-sectional study. The approval for the study was obtained from the IRB and COVID ramp up committee of University of North Carolina Greensboro (UNCG). Participants completed comprehensive hearing screening and preand postsilence ALR and P300 recordings were obtained. After the first ALR/P300 recording participants were exposed to ten minutes of silence. Participants completed a Qualtrics questionnaire to report any tinnitus perception that emerged during silence exposure. Absolute N1, P2 and P300 waveform amplitudes and latencies were identified and were entered into an SPSS spreadsheet for data analysis. Thirty adult females with normal pure tone hearing thresholds and no history of persistent tinnitus were included in the study. The mean age of the participants was 22.5 ± 3.9 years. When exposed to silence, eight (26.7%) participants perceived temporary tinnitus. N1 and P300 waveforms were smaller in amplitude and faster in latency in the tinnitus perception group; however, the ALR and P300 waveform latencies and amplitudes did not statistically differ significantly between the participants who perceived temporary tinnitus in silence and those who did not (p>0.05). The difference in waveform morphology between the tinnitus perception group and the non-tinnitus perception group revealed a greater difference in P300 amplitude after exposure to silence. Differences in ALR and P300 latencies and amplitudes were observed between the tinnitus perception group and non-tinnitus perception group, with smaller P300 amplitudes appearing in the group perceiving tinnitus. While the results did not statistically significant, this pattern may reflect a mismatch between the neuronal response in the auditory cortex (N1 and P2 amplitudes and latencies) and the neuronal activity in the modulatory network regions (P300).

IntroductionBilingualism significantly contributes to neuroplasticity in the brain, with research indicating enhanced auditory processing in bilingual individuals. Obligatory sensory components of the auditory late responses (ALRs) reflect primary and secondary auditory cortex activity, serving as an electrophysiological measure of auditory processing. This study aims to compare ALRs' obligatory components (P1-N1-P2) in bilingual (Turkish-Persian) and monolingual (Persian) young adults.MethodThis cross-sectional study analyzed ALRs in 28 monolingual and 28 bilingual participants aged 19 to 30 years, using a 70 dB nHL speech stimulus (/da/). ALRs were recorded monaurally with insert earphones. The study then compared the mean latency and amplitude of P1- N1- P2 complex in the right and left ear between two groups.ResultThe study revealed shorter latency for all three ALRs components in bilingual participants compared to monolinguals. This difference was statistically significant (P-value < 0.05) for N1 with right ear stimulation and P2 with right and left ear stimulations. No significant differences were found in the amplitude of P1-N1 and N1-P2 between the groups.ConclusionThe significant reduction in N1 and P2 latency observed in bilingual subjects' ALRs likely results from neural plasticity. This may enhance neural transmission and accelerate speech sound processing in the respective cortical regions. These latency changes could serve as a cortical neural biomarker distinguishing monolinguals from bilinguals, highlighting the impact of bilingualism on auditory processing efficiency.

Introduction Human auditory and vestibular systems change due to noise exposure. Professional musicians are often subjected to loud music and longer durations as part of their practice. Although the effects of music have been explored extensively on the auditory system, it is important to understand changes in the vestibular system also. The current study is aimed to compare cervical vestibular evoked myogenic potential (cVEMP) findings in nonmusicians and violinists to understand if there are any changes in the P1 and N1 latencies and absolute amplitudes in the violinists’ groups because of their exposure to violin music. Materials and Methods Twelve participants (6 nonmusicians and 6 violinists) of both genders were included in the study. Pure tone audiometry and distortion product otoacoustic emissions (DPOAEs) were performed on all the participants. cVEMP P1 and N1 latencies and absolute amplitudes were obtained, and overall mean differences were compared within and between groups. Results Pure tone average and DPOAE were within the normal range between and within the groups. Results indicate that P1 and N1 absolute amplitudes and latencies were slightly prolonged in the violinists’ group; however, the mean difference was not statistically significant. Comparison of mean absolute amplitudes and latencies between the ears in the violinists’ group showed longer latencies and greater absolute amplitudes in the left ear of violinists as compared with the right ear. In the study, the violinists’ group consisted of participants who had an average daily exposure of about one-and-a-half hours and had an experience of playing the instrument for more than 5 years. Conclusion cVEMP is useful in detecting early changes in the saccule that may occur due to noise exposure. It can be concluded that, even before a clinically detectable hearing loss or vestibular damage, changes in saccule are observed with the help of cVEMP and should be included in the audiovestibular test for early identification.

Listening in noisy situations demands cognitive effort. Recently, we have shown that the Wavelet Phase Synchronization Stability (WPSS) of Auditory Late Responses (ALRs) represents an objective method to estimate mental load in auditory environments. In literature only a limited number of publications can be found which focus on the effects of noise types and noise onset effects using syllable evoked ALRs. The objective of the present work was to analyze the influence of different parameters, like white and babble noise as well as different noise onset times 50, 300, 1000ms and continuous noise conditions, on syllable evoked ALRs. Also, the analysis of the WPSS, as used in previous work, has never been applied to see such effects on the ALRs. We found that noise onset times of 300ms or larger showed a good separation of the ALR components. Furthermore, the analysis of the WPSS for different scales showed a clear identification of the N1 components. However, the best type of noise, and noise onset configuration depends on the specific application. For investigations related to auditory processing of speech, ecological noises are preferred because they could be used to mimic everyday listening situations.

Introduction Learning a second language is an essential task in today's world, and is experienced by many children. The cognitive auditory-evoked potential (P300) is related to cognitive activity, attention and concentration, enabling the investigation of the effect of a second language on the central auditory pathway. Objective To analyze the effects of learning English on P300 latency and amplitude in children and to correlate them with age, time of exposure to English, and time in class. Method An observational, descriptive, cross-sectional and quantitative study, in which 33 children, aged between 5 and 9 years and 11 months, of both genders participated, 14 of them in the process of learning English (study group) and 19 without this experience (control group). All subjects had their P300 evaluated using the Intelligent Hearing Systems (IHS, Miami, FL, US) Smart EP equipment. A total of 300 binaural stimuli were used in 75 dBnHL, as well as 240 frequent and 60 rare stimuli, using the pairs /ba/ and /di/ respectively. Results There was a statistically significant difference regarding P300 latency between the groups, and children exposed to English classes had lower latency in this component. No statistical difference was found between P300 amplitudes. No correlation was observed regarding age, time of exposure to English, time in class, and electrophysiological responses. Conclusion The Children exposed to English classes had the most stimulating auditory pathway, because their P300 had lower latency, being a resource for the speech therapy clinic.

Idiopathic subjective tinnitus has a complex pathophysiology in which not only cochlear and central classical auditory pathways but also nonclassical auditory pathways of different parts of the brain are involved. Vestibuloocular and vestibulocollic pathways are the central projections of utricle and saccule used in the vestibular evoked myogenic potential (VEMP) test. Aim of this study was to investigate the effects of idiopathic subjective tinnitus on vestibuloocular and vestibulocollic pathways via VEMP. We prospectively analyzed 30 unilateral idiopathic subjective tinnitus patient's cervical, ocular VEMP tests, tinnitus handicap index scores, symptom duration and compared with contralateral ear and 35 healthy volunteers. The latencies and amplitudes of P1 and N1 waves were recorded and pathologic wave criteria was calculated according to healthy volunteer's data. In cervical VEMP there were significant longer latencies of P1 and N1 waves with respect to contralateral ear and control group. In ocular VEMP test, N1 and P1 latencies and amplitudes were not significantly different. The percentages of pathologic wave of the tinnitus side were not significantly higher in both cervical VEMP and ocular VEMP tests with respect to contralateral side. Tinnitus handicap index scores and symptom duration had no relationship with latency and amplitude of VEMP tests. Although cervical VEMP P1 and N1 latencies were significantly longer, subjective tinnitus did not result in pathological alterations in the VEMP test. Presence of subjective tinnitus is not an influencing factor in the VEMP interpretation.

ObjectiveTo investigate the effects of acoustic stimulation intensity on ocular and cervical vestibular evoked myogenic potential (oVEMP and cVEMP) responses elicited by air-conducted sound (ACS) in healthy children.MethodsThirteen healthy children aged 4–10 years and 20 healthy adults aged 20-40 years with normal hearing and tympanometry were enrolled in this study. All subjects received oVEMP and cVEMP tests under different acoustic stimulation intensities (131, 126, 121, 116, 111 and 106 dB SPL). Mean n1 latency, p1 latency, interpeak latency, amplitude and response rate were investigated and analyzed.ResultsAs the acoustic stimulation intensity decreased, for oVEMP, the response rate of children decreased from 100% (131, 126 and 121 dB SPL) to 57.69% (116 dB SPL), 26.92% (111 dB SPL) and 11.54% (106 dB SPL). The response rate of adults decreased from 100% (131 and 126 dB SPL) to 95% (121 dB SPL), 55% (116 dB SPL), 12.5% (111 dB SPL) and 2.5% (106 dB SPL). There were lower n1 latency, p1 latency and higher amplitude in children when comparing by acoustic stimulation intensities (p < 0.05). Regarding cVEMP, the response rate of children decreased from 100% (131, 126 and 121 dB SPL) to 88.46% (116 dB SPL), 53.85% (111 dB SPL) and 26.92% (106 dB SPL). The response rate of adults decreased from 100% (131 and 126 dB SPL) to 95% (121 dB SPL), 85% (116 dB SPL), 37.5% (111 dB SPL) and 7.5% (106 dB SPL). A statistically significant difference was found in amplitude at different acoustic stimulation intensities in both children and adults (p < 0.05). When stimulated by 131 dB SPL acoustic stimulation, there were lower n1 latency, p1 latency and higher amplitude in children in oVEMP and cVEMP compared with adults (p < 0.05).ConclusionThe response rate and amplitude of oVEMP and cVEMP in children and adults presented significant differences with a decrease in acoustic stimulation intensity. In this study, using 121 dB SPL for children and 126 dB SPL for adults during VEMP test could be regarded as safer stimulation intensities and thus reduced sound exposure.

The main goal of the research was to obtain a set of data for ability of speech in noise recognition using Polish word test (New Articulation Lists – NAL-93) with two different masking signals. The attempt was also made to standardise the background noise for Polish speech tests by creating babble noise for NAL-93. Two types of background noise were used for Polish word test – the babble noise and the speech noise. The short method was chosen in the study as it provided similar results to constant stimuli method using less word material. The experiment using both maskers was presented to 10 listeners with normal hearing. The mean SRT values for NAL-93 were −3.4 dB SNR for speech noise and 3.0 dB SNR for babble noise. In this regard, babble noise provided more efficient results. However, the SRT parameter for speech noise was more similar to values obtained for other Polish speech tests. The measurement of speech recognition using Polish word test is possible for both types of masking signals presented in the study. The decision as to which type of noise would be better in practice of hearing aid prosthetics remains an open-end question.

Abstract. We investigated the modality difference in the N2 and P3 components of event-related potentials (ERPs) between visual and auditory Go/No-go paradigms. We evaluated the relationship between RT and the amplitudes and latencies of N2 and P3 in visual and auditory Go/No-go paradigms. No significant differences were observed in the latencies of N2 and P3 between visual and auditory paradigms. Significant correlations were observed between RT and the latency of P3 in the visual and auditory paradigms. In contrast, the amplitudes of N2 and P3 were significantly larger in the visual paradigm than in the auditory paradigm. A significant correlation was observed between RT and the amplitude of P3 only in the auditory paradigm. These results suggested that there were two neural networks for the response execution and inhibitory function, common and uncommon, that depended on the stimulus modality.

Introduction: As hearing function is directly linked to language and communication abilities, hearing loss may negatively affect children’s cognitive development. Therefore, it is important that hearing-impaired children undergo cognitive function assessments to better understand how to alleviate this comorbidity. The P300 event-related potential measurement is a neurophysiological test increasingly used to objectively measure cognitive function. Aim: The aim of the study was to compare the latency and amplitude of P300 waves in children with profound sensorineural hearing loss (SNHL) with hearing aids and normal-hearing children aged 7–15 years old. Methods: A comparative cross-sectional study involving 15 children with profound SNHL and 15 children with normal hearing was conducted. The latency and amplitude of P300 waves in these children in response to auditory and visual stimuli were recorded and analyzed. Results: The mean P300 wave latency in children with SNHL was slightly longer than that in children with normal hearing, albeit insignificant (P = 0.578). Similarly, the amplitude of the P300 waves was not significantly smaller in children with SNHL (P = 0.885). Conclusions: SNHL children with hearing aid habilitation have comparable P300 amplitude and latency compare to normal-hearing children.

Introduction The number of stimuli is important to determine the quality of auditory evoked potential records. However, there is no consensus on that number in studies, especially in the sample studied.Objectives To investigate the influence of the number of rare stimuli on forming N2 and P3 components, with different types of acoustic stimuli.Methods Cross-sectional, descriptive, comparative study, approved by the ethics committee of the institution. The sample comprised 20 normal hearing adults of both sexes, aged 18 to 29 years old, with normal scores in the mental state examination and auditory processing skills. The event-related auditory evoked potentials were performed with nonverbal (1 kHz versus 2 kHz) and verbal stimuli (/BA/ versus /DA/). The number of rare stimuli varied randomly in the recordings, with 10, 20, 30, 40, and 50 presentations.Results P3 latency was significantly higher for nonverbal stimuli with 50 rare stimuli. N2 latency did not show any difference between the type and number of stimuli. The absolute P3 and N2-P3 amplitudes showed significant differences for both types of stimuli, with higher amplitude for 10 rare stimuli, in contrast with the other ones. The linear tendency test indicated significance only for the amplitude – as the number of rare stimuli increased, the amplitude tended to decrease.Conclusion The components were identifiable in the different numbers of rare stimuli and types of stimuli. The P3 and N2-P3 latency and amplitude increased with fewer verbal and nonverbal stimuli. Recording protocols must consider the number of rare stimuli.

The P300 results from focusing attention on rare stimuli in the midst of other frequent stimuli; it tests recent attention and memory, both of which depend on discriminating among verbal or nonverbal stimuli. AimTo compare the P300 with verbal and nonverbal stimuli in normal-hearing adults. Material and MethodA prospective study was made of 15 male subjects aged from 22 to 55, with no hearing complaints. The subjects underwent short and long latency (P300) auditory evoked potentials with verbal and non-verbal stimuli. ResultsThe mean P300 latency with verbal stimuli was significantly higher than the P300 with nonverbal stimuli. The P300 amplitudes were significantly lower for verbal compared with nonverbal stimuli. ConclusionThere were no differences between ears with respect to P300 latencies and amplitudes for both non-verbal and verbal stimuli. Latencies were higher with verbal stimuli; amplitudes had lower values.

Auditory Brain Development in Children with Hearing Loss – Part Two