Auditory Processing Assessment Research Articles

A longitudinal study on the development trajectory of auditory processing and its relationship with language development in Chinese preschool children with autism spectrum disorder: study protocol

BackgroundIt was reported that more than 96% of autism spectrum disorder (ASD) children are accompanied with different degrees of sensory processing abnormalities, and up to 50% of ASD children exhibit abnormal auditory response. Studies have confirmed that some ASD children’s abnormal auditory response may be related to their abnormal auditory processing. Prior research demonstrated that ASD children’s auditory processing has high heterogeneity, thus, ASD children’s auditory processing may have different developmental trajectories. However, no study has concentrated on the developmental trajectories of ASD children’s auditory processing. In addition, auditory processing plays a crucial role in ASD children’s language development, thus, ASD children’s different language development outcomes may be related to different auditory processing development tracks. Therefore, this study aims to explore the developmental trajectory of auditory processing in ASD children and analyze the relationship between different developmental trajectories of auditory processing and language impairment.Methods/DesignIn this study, 220 ASD children aging 3 years and 0 months to 4 years and 11 months are recruited as the research objects, and their demographic characteristics are collected. The subjects are tested for peripheral hearing, intelligence, and autism symptoms. Furthermore, ASD children’s auditory processing and language development are evaluated at baseline, 1 year, and 2 years later. In addition, ASD children’s auditory processing is evaluated by electrophysiological test and the Preschool Auditory Processing Assessment Scale. Moreover, ASD children’s language skills are assessed using the Language Development Assessment Scale for Children Aged 1–6. The various categories of the developmental trajectory of ASD children’s auditory processing are examined through the latent category growth model. Additionally, a hierarchical regression model is developed to analyze the predictive impact of different auditory processing development trajectories on language impairment in ASD children.DiscussionThis longitudinal study will explore the categories of auditory processing developmental trajectories in ASD children, and analyze the relationship between different categories of auditory processing developmental trajectories and language development, providing new ideas and targeted targets for the rehabilitation training of language impairment in ASD children, as well as promoting early and accurate interventions for ASD children.

Letter to the Editor Regarding “Development and Evaluation of the Persian Version of the Multiple Auditory Processing Assessment”

The Article Abstract is not available

Concussion acutely disrupts auditory processing in division I football student-athletes

ABSTRACT Introduction Diagnosis, assessment, and management of sports-related concussion require a multi-modal approach. Yet, currently, an objective assessment of auditory processing is not included. The auditory system is uniquely complex, relying on exquisite temporal precision to integrate signals across many synapses, connected by long axons. Given this complexity and precision, together with the fact that axons are highly susceptible to damage from mechanical force, we hypothesize that auditory processing is susceptible to concussive injury. Methods We measured the frequency-following response (FFR), a scalp-recorded evoked potential that assesses processing of complex sound features, including pitch and phonetic identity. FFRs were obtained on male Division I Collegiate football players prior to contact practice to determine a pre-season baseline of auditory processing abilities, and again after sustaining a sports-related concussion. We predicted that concussion would decrease pitch and phonetic processing relative to the student-athlete’s preseason baseline. Results We found that pitch and phonetic encoding was smaller post-concussion. Student-athletes who sustained a second concussion showed similar declines after each injury. Conclusions Auditory processing should be included in the multimodal assessment of sports-related concussion. Future studies that extend this work to other sports, other injuries (e.g. blast exposure), and to female athletes are needed.

Is It Possible to Use the Speech-Evoked Auditory Brainstem Response Test During Sleep as It Is Used During Wakefulness?

Background and Aim: It is important to know how much are the auditory electrophysi- ological tests affected by sleep and wakefulness to be employed in different situations. This problem is more important for the speech-evoked Auditory Brainstem Response (speech- ABR) test that is affected by higher-level processing. This study aimed to compare the results of the speech-ABR test between wakefulness and sleep states. Methods: Sixteen young male adults (aged 20–28 years) with normal hearing participated in this study. The speech-ABR to the /da/ syllable was recorded during wakefulness and sleep. Electroencephalography (EEG) and behavioral tests (eyes position, body movements, etc.) were monitored during the test time to confirm the sleep state. Results: The speech-ABR test parameters showed significant changes during sleep compared to wakefulness (latencies of waves V and A were longer and the amplitudes of waves V and A, the slope of V-A complex, and the spectral magnitude of F1 were lower). However, the spectral magnitude of higher frequencies was not significantly different. In addition, no significant statistical difference was observed in speech-ABR parameters between right and left ears. Conclusion: Although the speech-ABR originates from brainstem centers, unlike conventional click-evoked ABR, it is affected by sleep as it is affected by the higher-level auditory processing functions. Although, further studies are needed. However, our study opens the way for many applied auditory studies about the possibility to use speech-ABR for auditory processing assessments in sleep state of different population groups, such as neonates. Keywords: Auditory brainstem response; speech acoustics; sleep; electroencephalography

Development and Evaluation of the Italian Version of the Dichotic Digit Test: Insights from 39 Normal-Hearing Children Aged 11 to 13 years.

BACKGROUND The dichotic digit test (DDT) is one of the tests for the behavioral assessment of central auditory processing. Dichotic listening tests are sensitive ways of assessing cortical structures, the corpus callossum, and binaural integration mechanisms, showing strong correlations with learning difficulties. The DDT is presently available in a number of languages, each appropriate for the subject's native language. However, there is presently no test in the Italian language. The goal of this study was to develop an Italian version of the one-pair dichotic digit test (DDT-IT) and analyze results in 39 normal-hearing Italian children 11 to 13 years old. We used 2 conditions of presentation: free recall and directed attention (left or right ear), and looked at possible effects of sex and ear side. MATERIAL AND METHODS This study involved 3 steps: creation of the stimuli, checking their quality with Italian speakers, and assessment of the DDT-IT in our subject pool. The study involved 39 children (26 girls and 13 boys), aged 11-13 years. All participants underwent basic audiological assessment, auditory brainstem response, and then DDT-IT. RESULTS Results under free recall and directed attention conditions were similar for right and left ears, and there were no sex or age effects. CONCLUSIONS The Italian version of DDT (DDT-IT) has been developed and its performance on 39 normal-hearing Italian children was assessed. We found there were no age or sex effects for either the free recall condition or the directed attention condition.

Assessment of Peripheral and Central Auditory Processing after Treatment for Idiopathic Sudden Sensorineural Hearing Loss.

Introduction When cases of idiopathic sudden sensorineural hearing loss (SSNHL) are treated successfully, most clinicians assume the normality and symmetry of the auditory processing. This assumption is based on the recovery of the detection ability on the part of the patients, but the auditory processing involves much more than detection alone. Since certain studies have suggested a possible involvement of the central auditory system during the acute phase of sudden hearing loss, the present study hypothesized that auditory processing would be asymmetric in people who have experienced sudden hearing loss. Objective To assess the physiologic and electrophysiological conditions of the cochlea and central auditory system, as well as behavioral discrimination, of three primary aspects of sound (intensity, frequency, and time) in subjects with normal ears and ears treated successfully for SSNHL. Methods The study included 19 SSNHL patients whose normal and treated ears were assessed for otoacoustic emissions, speech auditory brainstem response, intensity and pitch discrimination, and temporal resolution in a within-subject design. Results The otoacoustic emissions were poorer in the treated ears compared to the normal ears. Ear- and sex-dependent differences were observed regarding otoacoustic emissions and pitch discrimination. Conclusion The asymmetrical processing observed in the present study was not consistent with the hearing threshold values, which might suggest that the central auditory system would be affected regardless of the status of the peripheral hearing. Further experiments with larger samples, different recovery scenarios after treatment, and other assessments are required.

Association between auditory processing and problem behaviors in preschool children: the mediating role of executive function

To investigate the association between auditory processing and problem behaviors in preschool children, as well as the mediating role of executive function. A total of 2 342 preschool children were selected from 7 kindergartens in Nanjing, China from June to August 2021. They were evaluated using Preschool Auditory Processing Assessment Scale, Conners Parent Symptom Questionnaire, and Behavior Rating Inventory of Executive Functioning-Preschool version. Children with different demographic features were compared in the scores and the abnormality rates of auditory processing, problem behaviors, and executive function. The influencing factors of the total scores of auditory processing, problem behaviors, and executive function were evaluated using multiple linear regression analysis. Whether executive function was a mediating factor between auditory processing and executive function was examined. Sex and grade were the main influencing factors for the total score of auditory processing (P<0.05), and sex, grade, parental education level, and family economic status were the main influencing factors for the total scores of problem behaviors and executive function (P<0.05). The auditory processing score (rs=0.458, P<0.05) and problem behavior score (rs=0.185, P<0.05) were significantly positively correlated with the executive function score, and the auditory processing score was significantly positively correlated with the problem behavior score (rs=0.423, P<0.05). Executive function played a partial mediating role between auditory processing and problem behaviors, and the mediating effect accounted for 33.44% of the total effect. Auditory processing can directly affect the problem behaviors of preschool children and indirectly affect problem behaviors through executive function.

Assessment of Central Auditory Processing in Children Using a Novel Tablet-Based Platform: Application for Low- and Middle-Income Countries.

Evaluate whether a portable, tablet-based central auditory processing (CAP) test system using native language training videos and administered by minimally trained community health workers can produce CAP results comparable to previously published norms. Our secondary aim was to determine subject parameters that influence test results. Cross-sectional study. Community-based settings in Chontales, Nicaragua, New Hampshire, and Florida. English- and/or Spanish-speaking children and adolescents (n = 245; average age, 12.20 yr; range, 6-18 yr). Completion of the following tests with responses comparable to published norms: Pure-tone average (PTA), gap detection threshold (GDT), fixed-level frequency threshold, masking level difference (MLD), Hearing in Noise Test (HINT), Dichotic Digits Test (DDT), and Frequency Pattern Recognition (FPR) test. GDT, HINT, and DDT had comparable results to previously published normative values. MLD and FPR results differed compared with previously published normative values. Most CAP tests (MLD, GDT, HINT) results were independent of age and PTA (p = 0.1-0.9). However, DDT was associated with age and PTA (p < 0.0001). Pediatric CAP testing can be successfully completed in remote low- and middle- income country environments using a tablet-based platform without the presence of an audiologist. Performance on DDT improved with age but deteriorated with hearing loss. Further investigation is warranted to assess the variability of FPR.

A comment on the order of report in two-pair dichotic digit testing in children assessed for auditory processing

Objective This clinical note aimed to 1) describe the order-of-report (OoR) strategies used by a large sample of children who completed 2pDD testing in the free-recall condition as part of an audiological assessment of auditory processing (AP), and 2) determine if use of OoR correlated with 2pDD test performance. Design A retrospective (case-review), single observation design. Study sample A convenient sample of 77 children (50 males and 27 females aged 7.0 to 17.4 years [median = 8.8 years]) referred to audiology for an AP assessment. Results The participating children used temporal more than ear or sequential OoR and showed decreased test scores with increased use of ear OoR. Conclusions These findings suggest children referred for an AP assessment could favour a temporal OoR when completing 2pDD testing for its opportunity to rehearse the first digit pair (possibly strengthening its memory trace) prior to processing the second digit pair, while their use of an ear OoR could come at the cost detrimental ear dominance effects that reduce their test performance. Future research could consider if similar results are observed in other child populations and if preferred dichotic processing strategy could inform auditory training for children with dichotic listening deficits.

Central auditory processing and self-perception questionnaire after acoustically controlled auditory training in individuals with mild traumatic brain injury.

To correlate behavioral assessment results of central auditory processing and the self-perception questionnaire after acoustically controlled auditory training. The study assessed 10 individuals with a mean age of 44.5 years who had suffered mild traumatic brain injury. They underwent behavioral assessment of central auditory processing and answered the Formal Auditory Training self-perception questionnaire after the therapeutic intervention - whose questions address auditory perception, understanding orders, request to repeat statements, occurrence of misunderstandings, attention span, auditory performance in noisy environments, telephone communication, and self-esteem. Patients were asked to indicate the frequency with which the listed behaviors occurred. Figure-ground, sequential memory for sounds, and temporal processing correlated with improvement in following instructions, fewer requests to repeat statements, increased attention span, improved communication, and understanding on the phone and when watching TV. Auditory closure, figure-ground, and temporal processing had improved in the assessment after the acoustically controlled auditory training, and there were fewer auditory behavior complaints.

Advancing Auditory Processing by Detecting Frequency-Following Responses Through a Specialized Machine Learning Model.

In this study, we explore the feasibility and performance of detecting scalp-recorded frequency-following responses (FFRs) with a specialized machine learning (ML) model. By leveraging the strengths of feature extraction of the source separation non-negative matrix factorization (SSNMF) algorithm and its adeptness in handling limited training data, we adapted the SSNMF algorithm into a specialized ML model with a hybrid architecture to enhance FFR detection amidst background noise. We recruited 40 adults with normal hearing and evoked their scalp recorded FFRs using the English vowel/i/with a rising pitch contour. The model was trained on FFR-present and FFR-absent conditions, and its performance was evaluated using sensitivity, specificity, efficiency, false-positive rate, and false-negative rate metrics. This study revealed that the specialized SSNMF model achieved heightened sensitivity, specificity, and efficiency in detecting FFRs as the number of recording sweeps increased. Sensitivity exceeded 80% at 500 sweeps and maintained over 89% from 1000 sweeps onwards. Similarly, specificity and efficiency also improved rapidly with increasing sweeps. The progressively enhanced sensitivity, specificity, and efficiency of this specialized ML model underscore its practicality and potential for broader applications. These findings have immediate implications for FFR research and clinical use, while paving the way for further advancements in the assessment of auditory processing.

Testing the Informativeness of Diverse Measures of Auditory Processing for Clinical Audiological Practice in Middle-Aged Adults in Mexico.

Standard clinical audiologic assessment is limited in its ability to capture variance in self-reported hearing difficulty. Additionally, the costs associated with clinical testing in audiology create financial barriers for hearing health care in developing countries like Mexico. This study used an open-source Spanish-language tool called PART (Portable Automated Rapid Testing) to test the hypothesis that a battery of assessments of auditory processing can complement standard clinical audiological assessment to better capture the variance of self-reported hearing difficulty. Forty-three adults between 40 and 69 years of age were tested in Mexico City using a traditional clinical pure-tone audiogram, cognitive screening, and a battery of PART-based auditory processing assessments including a speech-on-speech competition spatial release from masking task. Results were compared to self-reported hearing difficulty, assessed with a Spanish-language adaptation of the Hearing Handicap Inventory for the Elderly-Screening Version (HHIE-S). Several measures from the PART battery exhibited stronger correlations with self-reported hearing difficulties than the pure-tone audiogram. The spatial release from masking task best captured variance in HHIE-S scores and remained significant after controlling for the effects of age, audibility, and cognitive score. The spatial release from masking task can complement traditional clinical measures to better account for patient's self-reported hearing difficulty. Open-source access to this test in PART supports its implementation for Spanish speakers in clinical settings around the world at low cost. https://doi.org/10.23641/asha.24470140.

Changes in Auditory Evoked Potentials Increase the Chances of Adults Having Central Auditory Processing Disorder.

Introduction Auditory evoked potentials are widely used in clinical practice to complement the assessment of central auditory processing. However, it is necessary to understand whether these potentials are highly accurate, to assist in the diagnosis of auditory processing disorder. Objective To measure the accuracy of middle and long latency auditory evoked potentials in the diagnosis of auditory processing disorder in adults. Methods This is a case-control study, formed by a control group of 30 individuals with normal auditory processing assessment, and a case group composed of 43 individuals with altered auditory processing assessment. Their sensitivities, specificities, accuracies, positive and negative predictive values for the diagnosis of alterations were measured and compared between the potentials. Results The accuracies of the middle and long latency potentials were 51% and 67%, respectively. The P1-N1-P2 and N2-P300 complexes had an accuracy of 57.5% and 58.9%, respectively. The cognitive potential P300 showed an accuracy of 55%. There was no significant result for the middle-latency potential (OR = 1.8; 95% CI: 0.6-5.4, p > 0.42) and for P300 (OR = 2.63, 95% CI: 0.85-8.43, p > 0.11). However, the result was significant for the long-latency potential (OR = 6.3; 95% CI: 2-19.6, p < 0.01). There was a significant result for the P1-N1-P2 complexes (OR = 6.76, 95% CI:1.4-32.5, p = < 0.010) and N2-P300 (OR = 3.60; 95% CI: 10.16-11.20, p < 0.039). Conclusion Individuals with altered long-latency auditory evoked potential are more likely to have auditory processing disorder and, as such, this test can be used as a complementary tool to confirm the diagnosis.

Behavioral Assessment of Central Auditory Processing in Turner Syndrome.

Introduction Turner syndrome (TS) affects ∼ 1 in 2,500 live births. The presence of hearing alterations is one of the comorbidities found in this syndrome. Objective The present study aimed to evaluate the central auditory abilities in TS and to associate the alterations found with the cytogenetic pattern of the syndrome. Methods We included children and adults aged 9 to 39 years old, diagnosed with TS, with numerical or structural alterations of sex chromosomes in their karyotype. A battery of behavioral tests of central auditory processing (CAP) was performed, including a test within the modalities: monoaural low-redundancy, dichotic listening, binaural interaction, and temporal processing (resolution and ordering). We studied auditory skills in the total sample and in the sample stratified by age, divided into groups: G1 (9 to 13 years old), G2 (14 to 19 years old), and G3 (20 to 31 years old). For the association of the cytogenetic pattern, the division was T1 (chromosome monosomy X), and T2 (other TS cytogenetic patterns). Statistical analysis presented data expressed as median and interquartile range for numerical data and as frequency and percentage for categorical data. Results We found alterations in four auditory skills in the three age groups, but there was a statistically significant difference between the age groups only in the Gaps in Noise Test (GIN) ( p -value = 0.009). Regarding karyotype, a greater number of alterations in the T1 cytogenetic pattern (chromosome monosomy X) was observed in four auditory skills, but without a statistically significant difference. Conclusion The alterations found point to an impairment in CAP in TS.

Identification of Auditory Processing Disorder Based on the Persian Version of Multiple Auditory Processing Assessment in School-aged Children in Arak City, Iran

Background and Objectives: Auditory processing (AP) takes place throughout the central auditory nervous system. Therefore, to correctly assess auditory processing disorder (APD), it is necessary to use a test battery so that each of these tests can evaluate specific auditory skills. Therefore, considering the importance of detecting children with APD, the Persian version of the multiple auditory processing assessment (MAPA-P) was used in the present study. Methods: The study method was descriptive-analytical and cross-sectional. A total of 300 children aged 9-12 years old in equal numbers in both genders and at any age, from 7 primary schools in Arak City, Iran were enrolled. After ensuring the health of children’s peripheral hearing level, to check their central auditory system, the MAPA-P test battery was performed on laptops with headphones. Analysis of variance (ANOVA) and independent t-test were used to analyze the results. The mean scores in each age group were calculated and finally, the prevalence of APD was determined based on the cut-off point of the whole test. Results: The results showed that the mean scores in all 5 tests had a statistically significant difference in different age groups (P&lt;0.0001), and the mean scores increased with age. Also, no significant difference was observed in the scores of any of the 5 tests between the two genders (P&gt;0.05). The prevalence of APD in the school-age population was 5%. Conclusion: According to the valid results of the MAPA model in many studies, the Persian version of this test battery has been introduced as a standardized test battery. In addition to covering the three crucial domains of AP, it can easily be used in a calm classroom using a CD-RAM. The results of the present study showed that 5% of the children were suspected of APD, which was consistent with the results of the other studies.

Benefits of intervention in the Central Auditory Nervous System in individuals with Neurofibromatosis Type 1.

To verify the effectiveness of acoustically controlled auditory training in individuals with Neurofibromatosis Type 1. The sample consisted of individuals with Neurofibromatosis Type 1, randomly distributed into two groups, making up the intervention group: individuals undergoing formal auditory training; and the comparison group: individuals who were not submitted to the intervention. Behavioral assessment of central auditory processing and electrophysiological evaluation, composed by Brainstem Auditory Evoked Potential and Long Latency-P300 Auditory Evoked Potential, were evaluated in three moments of evaluations: initial evaluation, reevaluation and after four months of reevaluation and comparing the performance between the groups. Better performances in central auditory processing were observed after the formal auditory training in the intervention group with significant differences between the evaluations and performance maintenance four months after the end of the training. Significant differences were observed between the groups in the evaluations after the intervention. The electrophysiological evaluation shows unsystematic variation in the short latency potentials and changes in the long latency potentials with the appearance of the P3 wave after the intervention. The behavioral and electrophysiological evaluation in group that was not submitted to the intervention demonstrated that there is no improvement without the intervention, with deterioration of performance. Significant differences were observed in the behavioral and electrophysiological evaluations, in favor of the group submitted to formal auditory training. Formal auditory training is effective in rehabilitation in individuals with Neurofibromatosis Type 1. Neurofibromatosis 1; Hearing Disorders; Auditory Perceptual Disorders; Acoustic Stimulation; Evoked Potentials, Auditory.

Development and Standardization of Low-Verbal Material for Assessment of Central Auditory Processing in Arabic Language

Development and Standardization of Low-Verbal Material for Assessment of Central Auditory Processing in Arabic Language

Application of Preschool Auditory Processing Assessment Scale in children with attention deficit hyperactivity disorder

To investigate the characteristics of auditory processing (AP) in preschool children with attention deficit hyperactivity disorder (ADHD) using Preschool Auditory Processing Assessment Scale (hereafter referred to as "auditory processing scale"). A total of 41 children with ADHD and 41 typically developing (TD) children were assessed using the auditory processing scale, SNAP-IV rating scale, and Conners' Kiddie Continuous Performance Test (K-CPT). The auditory processing scale score was compared between the TD and ADHD groups. The correlations of the score with SNAP-IV and K-CPT scores were assessed. Compared with the TD group, the ADHD group had significantly higher total score of the auditory processing scale and scores of all dimensions except visual attention (P<0.05). In the children with ADHD, the attention deficit dimension score of the SNAP-IV rating scale was positively correlated with the total score of the auditory processing scale (rs30=0.531, P<0.05; rs27=0.627, P<0.05) as well as the scores of its subdimensions, including auditory decoding (rs=0.628, P<0.05), auditory attention (rs=0.492, P<0.05), and communication (rs=0.399, P<0.05). The hyperactivity-impulsivity dimension score of the SNAP-IV rating scale was positively correlated with the hyperactivity-impulsivity dimension score of the auditory processing scale (rs=0.429, P<0.05). In the children with ADHD, the attention deficit dimension score of the K-CPT was positively correlated with the total score (rs30=0.574, P<0.05; rs27=0.485, P<0.05) and the hyperactivity-impulsivity dimension score (rs=0.602, P<0.05) of the auditory processing scale. Preschool children with ADHD have the risk of AP abnormalities, and the auditory processing scale should be used early for the screening and evaluation of AP abnormalities in children.

Central Auditory Processing Dysfunction in Service Members and Veterans: Treatment Considerations and Strategies.

Military risk factors such as blast exposure, noise exposure, head trauma, and neurotoxin exposure place Service members and Veterans at risk for deficits associated with auditory processing dysfunction. However, there is no clinical guidance specific to the treatment of auditory processing deficits in this unique population. We provide an overview of available treatments and their limited supporting evidence for use in adults, emphasizing the need for multidisciplinary case management and interdisciplinary research to support evidence-based solutions. We explored relevant literature to inform the treatment of auditory processing dysfunction in adults, with emphasis on findings involving active or former military personnel. We were able to identify a limited number of studies, pertaining primarily to the treatment of auditory processing deficits through the use of assistive technologies and training strategies. We assessed the current state of the science for knowledge gaps that warrant additional study. Auditory processing deficits often co-occur with other military injuries and may pose significant risk in military operational and occupational settings. Research is needed to advance clinical diagnostic and rehabilitative capabilities, guide treatment planning, support effective multidisciplinary management, and inform fitness-for-duty standards. We emphasize the need for an inclusive approach to the assessment and treatment of auditory processing concerns in Service members and Veterans and for evidence-based solutions to address complex military risk factors and injuries.

Standardization of Latency and Amplitude Values of Short, Middle and Long Latency Auditory Evoked Potentials in Adults.

Introduction Auditory processing refers to the efficiency and effectiveness with which the central auditory nervous system uses auditory information. Middle- and long-latency auditory evoked potentials are objective electrophysiological tests that can complement the diagnosis of alterations involving central auditory processing. Objective To standardize latency and amplitude values for short-, middle-, and long-latency auditory evoked potentials in adults with normal hearing thresholds. Methods This is a cross-sectional study. Thirty-three adults with normal hearing thresholds, without hearing complaints, and with normal central auditory processing were evaluated. All underwent basic audiological evaluation, central auditory processing assessment, and short-, middle-, and long-latency auditory evoked potentials. Results Absolute latency and interpeak values for middle- and long-latency auditory evoked potentials were lower than internationally suggested. However, for the brainstem auditory evoked potential, the means were within the range considered as normal, as suggested in the equipment. Conclusion The present study provided measurements of normal latencies and amplitudes for short-, middle-, and long-latency auditory evoked potentials in adults.