Presence Of Background Noise Research Articles

Do Patients Benefit From a Cochlear Implant When They Qualify Only in the Presence of Background Noise?

To compare the difference in pre- to postoperative speech performance of patients qualifying for a cochlear implant (CI) in quiet, +10 dB signal-to-noise ratio (SNR), and +5 dB SNR. Retrospective. Tertiary referral center. Fifty-eight post-lingually deafened, unilateral CI recipients from three Groups were included: 1) those who met CI candidacy criteria with AzBio sentences in quiet, 2) in noise at +10 dB SNR but not in quiet, 3) and in noise at +5 dB SNR but not in quiet or +10 dB SNR. Unilateral CI. Pre- and 1 year postoperative speech recognition scores. Best-aided AzBio speech recognition of individuals in Group 1 improved significantly for all test conditions and improved significantly for Groups 2 and 3 in the +10 and +5 dB SNR test conditions postoperatively. When tested with their CI alone however, while AzBio speech recognition of individuals in Group 1 and Group 2 improved significantly in the quiet and +10 dB SNR conditions, speech recognition was not significantly changed postoperatively under any testing condition for individuals in Group 3. While individuals qualifying for a CI only in the +5 dB SNR condition may derive significant benefit from implantation in best aided conditions, speech understanding outcomes can be more variable thus warranting additional counseling before implantation and case-by-case consideration of listening needs and goals.

Analysis of Language Errors in Speakers Who Are Bilingual Under Quiet and Background Noise Conditions

Purpose This study discusses the ways in which the presence of background noise may adversely affect bilingual students' ability to repeat speech, specifically, whether the presence of background noise increases lexical, grammatical, omission, and other errors on the AzBio Sentence Test. Method Participants consisted of 15 monolingual English (first language) speakers and 41 bilingual (second language [L2]) speakers from Spanish, Portuguese, and Korean language groups, ranging from students who learned English after the age of 4 years to adulthood. Participants completed the AzBio Sentence Test in both quiet and background noise environments. A language analysis was conducted, and errors were classified under categories of lexical, grammatical, omissions, and other. Results The results of this study show that L2 speakers made more lexical, grammatical, omissions, and other errors than first language speakers on the AzBio Sentence Test. In background noise, all bilingual language groups made more errors than monolinguals. Portuguese speakers notably made more omissions than other language groups. This study also shows that participants who were introduced to English at a younger age made fewer errors. Conclusions In conclusion, our results corroborate previous research, indicating that bilingual speakers have more difficulty accurately interpreting speech in the presence of background noise. These findings have implications for classroom instruction considering the statistically higher percentage of omissions made by L2 speakers.

Effect of exceeding compliance voltage on speech perception in cochlear implants

ObjectivesIn cochlear implants, the maximum current I (Amperes) that can be delivered on a cochlear implant electrode is determined by V = I * R, where V = compliance voltage (Volts) and R = electrode impedance (Ohms). Generally, electrode impedances are measured during each clinical visit and are used to set electrical stimulation parameters in cochlear implants. However, electrode impedances can rise during the course of cochlear implant use and lead to electrical stimulation voltage requirements exceeding the maximum compliance voltage of the medical device. Electric stimulation requirements that exceed the compliance voltage lead to clipping of the biphasic electrical pulse (current going into the cochlea) and are known to adversely affect cochlear implant outcomes. DesignThirteen (11 unilateral and 2 bilateral) Advanced Bionics cochlear implant patients with a HiRes 90k™ cochlear implant participated in this study. Speech perception scores were measured using the patient's baseline clinical program with the most comfortable loudness levels (M-levels) and the following four test programs: (1) stimulation clipped at 15% below clinical M-levels (15%C) (2) stimulation clipped at 30% below clinical M-levels (30%C) (3) M-levels decreased by 15% (15%M) and (4) M-levels decreased by 30% (30%C). Speech perception scores were measured using AzBio sentences presented at 60 dB SPL in quiet and in the presence of multi-talker babble (+10 dB SNR). ResultsRelative to the clinical baseline program, speech perception scores with the four test programs decreased in both quiet and noisy listening conditions. In quiet, speech perception scores measured with the 30%M and 30%C programs were significantly (p < 0.001) poorer than the baseline program. No significant differences in speech perception scores were measured between the baseline and the 15%C or 15%M programs. In the noisy listening condition, speech perception scores were significantly poorer than the baseline program for the 15%C (p = 0.008), 30%C (p < 0.001), and 30%M (p < 0.001) programs. No significant differences in speech perception scores were obtained between the baseline and the 15%M program in the noisy listening condition. Speech perception scores measured with the 30%C program were significantly (p < 0.001) poorer than those with the 30%M program, suggesting that clipping was more detrimental than reducing electrical stimulation levels. ConclusionSmall amounts (15%) of clipping can significantly decrease speech perception in the presence of background noise. Large amounts (30%) of both clipping and M-level reduction may lead to significantly poorer speech perception in quiet and in background noise. The decrease in speech perception scores can most likely be attributed to reduced volume and poorer spectro-temporal representation. Therefore, it is important to establish comfortably loud electrical stimulation levels without exceeding the compliance voltage to maximize cochlear implant outcomes.

Deep Learning-Based Portable Device for Audio Distress Signal Recognition in Urban Areas

Real-time automatic identification of audio distress signals in urban areas is a task that in a smart city can improve response times in emergency alert systems. The main challenge in this problem lies in finding a model that is able to accurately recognize these type of signals in the presence of background noise and allows for real-time processing. In this paper, we present the design of a portable and low-cost device for accurate audio distress signal recognition in real urban scenarios based on deep learning models. As real audio distress recordings in urban areas have not been collected and made publicly available so far, we first constructed a database where audios were recorded in urban areas using a low-cost microphone. Using this database, we trained a deep multi-headed 2D convolutional neural network that processed temporal and frequency features to accurately recognize audio distress signals in noisy environments with a significant performance improvement to other methods from the literature. Then, we deployed and assessed the trained convolutional neural network model on a Raspberry Pi that, along with the low-cost microphone, constituted a device for accurate real-time audio recognition. Source code and database are publicly available.

Robust EEG-Based Decoding of Auditory Attention With High-RMS-Level Speech Segments in Noisy Conditions

The attended speech stream can be detected robustly, even in adverse auditory scenarios with auditory attentional modulation, and can be decoded using electroencephalographic (EEG) data. Speech segmentation based on the relative root-mean-square (RMS) intensity can be used to estimate segmental contributions to perception in noisy conditions. High-RMS-level segments contain crucial information for speech perception. Hence, this study aimed to investigate the effect of high-RMS-level speech segments on auditory attention decoding performance under various signal-to-noise ratio (SNR) conditions. Scalp EEG signals were recorded when subjects listened to the attended speech stream in the mixed speech narrated concurrently by two Mandarin speakers. The temporal response function was used to identify the attended speech from EEG responses of tracking to the temporal envelopes of intact speech and high-RMS-level speech segments alone, respectively. Auditory decoding performance was then analyzed under various SNR conditions by comparing EEG correlations to the attended and ignored speech streams. The accuracy of auditory attention decoding based on the temporal envelope with high-RMS-level speech segments was not inferior to that based on the temporal envelope of intact speech. Cortical activity correlated more strongly with attended than with ignored speech under different SNR conditions. These results suggest that EEG recordings corresponding to high-RMS-level speech segments carry crucial information for the identification and tracking of attended speech in the presence of background noise. This study also showed that with the modulation of auditory attention, attended speech can be decoded more robustly from neural activity than from behavioral measures under a wide range of SNR.

A real-time wavelet-based algorithm for improving speech intelligibility

A wavelet-based algorithm to improve speech intelligibility is reported. The speech signal is split into frequency sub-bands via a multi-level discrete wavelet transform. Various gains are applied to the sub-band signals before they are recombined to form a modified version of the speech. Dynamic range compression then follows to control the peak amplitude. The sub-band gains are adjusted while keeping the overall signal energy unchanged, and the speech intelligibility under simulated hearing loss conditions and various background interference is enhanced and evaluated objectively and quantitatively using Google Speech-to-Text transcription. For English and Chinese noise-free speech, overall intelligibility is improved, and the transcription accuracy can increase by over 80 percentage points by reallocating the spectral energy toward the mid-frequency sub-bands, effectively increasing the consonant-vowel intensity ratio. This is reasonable since the consonants are relatively weak and of short duration, and are therefore the most likely to become indistinguishable in the presence of background noise or high frequency hearing impairment. For speech already corrupted by noise, improving intelligibility is challenging but still realizable. The proposed algorithm is implementable in real-time and comparatively simpler than previous algorithms. Potential applications include speech transmission, hearing aids, machine listening, and a better understanding of speech intelligibility.

Preschool aged word learning from storybooks in the presence of background noise

Parents frequently read to their young children, and this can serve as an important opportunity for word learning. While some of these book-reading activities take place in quiet settings, others may occur in the presence of background noise; we were interested in how different types of noise might interfere with word learning. 18 children aged 3.5–5.5 saw and heard a digitized storybook containing 8 consonant-vowel-consonant (CVC) novel “words,” and then were tested on their learning. The words were presented in two types of maskers: single male talker in a foreign language and broadband noise. Following the story, word learning was assessed in two ways by: selecting the picture that matched a named referent in a 3AFC and producing the name of a referent. We found a main effect of noise type in the first measure, such that participants had greater accuracy in the broadband noise than in the single talker condition. There was an effect of age in the production measure, but no effect of noise type. These findings are consistent with previous word recognition work that suggests that broadband noise interferes less with learning than a background talker. Future work will expand on the specific features of the maskers that may interfere with word learning success.

Comparison of the recognition scores of stop and fricative consonants in babble noise between musicians and non-musicians

Everyday communication mostly occurs in the presence of various background noises and competing talkers. Studies have shown that musical training could have a positive effect on auditory processing, particularly in challenging listening situations. To our knowledge, no groups have specifically studied the advantage of musical training on perception of consonants in the presence of background noise. We hypothesized that musician advantage in speech in noise processing may also result in enhanced perception of speech units such as consonants in noise. Therefore, this study aimed to compare the recognition of stops and fricatives, which constitute the highest number of Persian consonants, in the presence of 12-talker babble noise between musicians and non-musicians. For this purpose, stops and fricatives presented in the consonant-vowel-consonant format and embedded in three signal-to-noise ratios of 0, −5, and −10 dB. The study was conducted on 40 young listeners (20 musicians and 20 non-musicians) with normal hearing. Our outcome indicated that musicians outperformed the non-musicians in recognition of stops and fricatives in all three signal-to-noise ratios. These findings provide important evidence about the impact of musical instruction on processing of consonants and highlight the role of musical training on perceptual abilities.

EVALUATION OF (GPS/GLONASS) PATCH VERSUS RF GPS (L1) PATCHANTENNA PERFORMANCE PARAMETER

In any wireless communication network and system an antenna is an important element along the propagation path of an electrical signals. Antenna module is a vital component of automated driving systems, it should function as needed in dGPS, HD map correction services, and radio and navigation systems. The main scope of this engineering research work involves the evaluation and determining the performance parameter and characteristic of the GPS/GLONASS patch vs RF GPS L1(1.57542 GHz) patch antenna characteristic. FEKO simulation studies are carried out to extensively compare, make an assessment and evaluate the characteristic and performance parameter, such as the average/passive gain of the proposed antenna in the presence of background noise. Prior to the start of the FEKO simulation studies, a physical mechanical dimension measurements via a Digital instrumentation were conducted for the following: Radiating Element Size: The actual length (L), and width (W), Substrate Material Size: The substrate length (Lsub), width (Wsub), and height (h). The proposed antenna model for GPS only patch antenna operating at 1.57542 GHz and the dual band patch antenna resonating at 1.5925 GHz are developed. To be specific, this work presents the design, modeling, determining passive gain of the RF GPS L1 patch vs. dual band patch antenna with intended targeted applications within the automotive system and space. Simulation are undertaken to generate the RF GPS L1 patch and dual band patch antenna structure respectively for the sole purpose of evaluating the performance of the proposed dual band antenna. Simulation are performed rather than mathematical modelling. The emphasis of this paper is how to obtain the equivalent amount of total passive gain in a GPS vs. that of dual band antenna.

Active-beacon-based driver sound separation system for autonomous vehicle applications

Voice recognition technology can almost accurately recognize a user’s voice in the absence of background noise or when the noise levels are extremely low. However, voice recognition in the presence of background noise with various voice signals is complicated. The problem in the current voice separation scheme is that though voice separation is possible from mixed voice signals, a permutation problem occurs that renders it difficult to identify the desired signal among the separated signals. In this paper, we propose a driver voice separation method for autonomous vehicles. To solve the permutation problem, active-beacon-based driver sound separation (ABDSS) utilizing active sound is used to distinguish the driver’s sound. After recording the voice work, simulation was performed. In the simulation, the proposed method succeeded in separating and distinguishing the original voice signals from the mixed voice signals. In addition, the coherence, kurtosis, and skewness calculation were used to verify that the separated signals were correctly identified in the simulation. Therefore, the proposed method is simpler in terms of hardware configuration than the existing methods and it is suitable for in-vehicle voice separation systems as well.

Spin current nano-oscillator (SCNO) as a potential frequency-based, ultra-sensitive magnetic biosensor: a simulation study

This work is a micromagnetic simulation-based study on the GHz-frequency ferromagnetic resonances (FMR) for the detection of magnetic nanoparticles (MNPs) using spin current nano-oscillator (SCNO) operating in precession mode. Capture antibody-antigen-detection antibody-MNP complex on the SCNO surface generates magnetic fields that modify the FMR peaks and generate measurable resonance peak shifts. Moreover, our results strongly indicate the position-sensitive behavior of the SCNO biosensor and demonstrate ways to eradicate this effect to facilitate improved bio-sensing. Additionally, a study has been made on how MNPs with different sizes can alter the SCNO device performance. This simulation-based study on the SCNO device shows the feasibility of a frequency-based nano-biosensor with the sensitivity of detecting a single MNP, even in presence of background noise.

μLED‐based optical cochlear implants for spectrally selective activation of the auditory nerve

Electrical cochlear implants (eCIs) partially restore hearing and enable speech comprehension to more than half a million users, thereby re‐connecting deaf patients to the auditory scene surrounding them. Yet, eCIs suffer from limited spectral selectivity, resulting from current spread around each electrode contact and causing poor speech recognition in the presence of background noise. Optogenetic stimulation of the auditory nerve might overcome this limitation as light can be conveniently confined in space. Here, we combined virus‐mediated optogenetic manipulation of cochlear spiral ganglion neurons (SGNs) and microsystems engineering to establish acute multi‐channel optical cochlear implant (oCI) stimulation in adult Mongolian gerbils. oCIs based on 16 microscale thin‐film light‐emitting diodes (μLEDs) evoked tonotopic activation of the auditory pathway with high spectral selectivity and modest power requirements in hearing and deaf gerbils. These results prove the feasibility of μLED‐based oCIs for spectrally selective activation of the auditory nerve.

An Efficient Experimental Methodology for the Assessment of the Dynamic Behaviour of Resilient Elements.

The assessment of the dynamic behaviour of resilient elements can be performed using the indirect method as described in the standard ISO 10846-3. This paper presents a methodology for control the error on the estimation of the frequency response functions (FRF) required for the application of the indirect method when sweep sine excitation is used. Based on a simulation process, this methodology allows for the design of the sweep sine excitation parameters, i.e., the sweep rate and the force amplitude, to control three types of errors associated to the experimentally obtained FRF in the presence of background noise: a general error of the FRF in a selected frequency range, and the errors associated to the amplitude and the frequency of the FRF resonance peak. The signal processing method used can be also tested with this methodology. The methodology has been tested in the characterisation of two different resilient elements: an elastomer and a coil spring. The simulated error estimations has been found to be in good agreement with the errors found in the measured FRF. Furthermore, it is found that for large signal-to-noise ratios, both sweep rate and force amplitude significantly affect the FRF estimation error, while, for small signal-to-noise ratios, only the force amplitude can control the error efficiently. The current methodology is specially interesting for laboratory test rigs highly used for the dynamic characterisation of resilient elements which are required to operate efficiently, since it can be used for minimising test times and providing quality assurance. Moreover, the application of this methodology would be specially relevant when characterisation is done in noisy environments.

An ensemble technique for speech recognition in noisy environments

&lt;span&gt;Automatic speech recognition (ASR) is a technology that allows a computer and mobile device to recognize and translate spoken language into text. ASR systems often produce poor accuracy for the noisy speech signal. Therefore, this research proposed an ensemble technique that does not rely on a single filter for perfect noise reduction but incorporates information from multiple noise reduction filters to improve the final ASR accuracy. The main factor of this technique is the generation of K-copies of the speech signal using three noise reduction filters. The speech features of these copies differ slightly in order to extract different texts from them when processed by the ASR system. Thus, the best among these texts can be elected as final ASR output. The ensemble technique was compared with three related current noise reduction techniques in terms of CER and WER. The test results were encouraging and showed a relatively decreased by 16.61% and 11.54% on CER and WER compared with the best current technique. ASR field will benefit from the contribution of this research to increase the recognition accuracy of a human speech in the presence of background noise.&lt;/span&gt;

Acceptable Noise Level Stability Over a One-Year Period of Time.

The acceptable noise level (ANL) is a measure of willingness to listen to speech in the presence of background noise and is thought to be related to success with amplification. To date, ANLs have only been assessed over short periods of time, including within a session and over a 3-week and 3-month time period. ANL stability over longer periods of time has not been assessed. The purpose was to examine the stability of ANL over a 1-year time period. A repeated-measures, longitudinal study was completed. Thirty young adults with normal hearing served as participants. The participants were tested at two different sites. Two trials of most comfortable listening levels (MCLs), background noise levels (BNLs), and ANLs were assessed for each participant during three experimental sessions: at 0 months, 6 months, and 1 year. Two-way repeated-measures analysis of variances revealed no significant change in MCLs, BNLs, or ANLs within a session or over a 1-year time period. These results indicate that ANLs remain stable for 1 year in listeners with normal hearing. The finding that the ANL is stable over a longer period of time supports the theory that the ANL is an inherent trait of the listener and mediated at in the central auditory nervous system.

The Effect of Unilateral Hearing Protection on Vocal Intensity With Varying Degrees of Background Noise

The Lombard effect (LE) is a phenomenon in which speakers adjust their vocal production by raising the volume in noisy environments. As a result, the LE can create problems of vocal strain, fatigue and potential injury. This study aims to examine the difference in vocal intensity output in subjects wearing unilateral hearing protection versus no hearing protection in the presence of background noise. Each subject was seated inside a sound booth wearing a head-mounted microphone. Subjects were asked to read an excerpt from "The Rainbow Passage" while various levels of background noise were played: 50, 60, 70, and 80 dBA (Multitalker Babble). Each noise level was played while the subject was with and without unilateral ear protection (Optime 98 Earmuff [3M]) in random order. The earmuff has a noise reduction rating of 25 dB. After each reading of the text, subjects were asked to rate communication disturbance, vocal clarity, and discomfort during talking using a 10 cm visual analogue scale. The LE is reduced from 0.38 dB/dB to 0.29 dB/dB with unilateral ear occlusion. However, self-perception of disturbance, clarity and comfort were not affected by unilateral occlusion, only by noise level. Unilateral hearing protection reduces the LE and may protect against phonotrauma when speaking in an environment with loud background noise.

Streaming of Repeated Noise in Primary and Secondary Fields of Auditory Cortex.

Statistical regularities in natural sounds facilitate the perceptual segregation of auditory sources, or streams. Repetition is one cue that drives stream segregation in humans, but the neural basis of this perceptual phenomenon remains unknown. We demonstrated a similar perceptual ability in animals by training ferrets of both sexes to detect a stream of repeating noise samples (foreground) embedded in a stream of random samples (background). During passive listening, we recorded neural activity in primary auditory cortex (A1) and secondary auditory cortex (posterior ectosylvian gyrus, PEG). We used two context-dependent encoding models to test for evidence of streaming of the repeating stimulus. The first was based on average evoked activity per noise sample and the second on the spectro-temporal receptive field. Both approaches tested whether differences in neural responses to repeating versus random stimuli were better modeled by scaling the response to both streams equally (global gain) or by separately scaling the response to the foreground versus background stream (stream-specific gain). Consistent with previous observations of adaptation, we found an overall reduction in global gain when the stimulus began to repeat. However, when we measured stream-specific changes in gain, responses to the foreground were enhanced relative to the background. This enhancement was stronger in PEG than A1. In A1, enhancement was strongest in units with low sparseness (i.e., broad sensory tuning) and with tuning selective for the repeated sample. Enhancement of responses to the foreground relative to the background provides evidence for stream segregation that emerges in A1 and is refined in PEG.SIGNIFICANCE STATEMENT To interact with the world successfully, the brain must parse behaviorally important information from a complex sensory environment. Complex mixtures of sounds often arrive at the ears simultaneously or in close succession, yet they are effortlessly segregated into distinct perceptual sources. This process breaks down in hearing-impaired individuals and speech recognition devices. By identifying the underlying neural mechanisms that facilitate perceptual segregation, we can develop strategies for ameliorating hearing loss and improving speech recognition technology in the presence of background noise. Here, we present evidence to support a hierarchical process, present in primary auditory cortex and refined in secondary auditory cortex, in which sound repetition facilitates segregation.

The effect of insular cortex lesion on hyperacusis-like behavior in rats

Background and objectives: Hyperacusis is hypersensitivity and extreme response to the intensity of sound that is tolerable in normal subjects. The mechanisms underlying hyperacusis has not been well understood, specially the role of insular cortex. The aim of this study is to investigate the role of insular cortex in hyperacusis like behavior. Material and methods: The number of 33 male wistar rats weighting 170-250 gr were allocated randomly in three groups; control, sham, and insular lesion. Auditory startle responses (ASR) to different intensities of stimuli (70, 80, 90, 100, and110 dB without background noise as well as 110 dB in the presence of 70, 80 dB background noise) were measured before and up to four weeks after intervention. Results: Data analyses showed an increase in ASR to 100 dB stimulus without background noise one week after insular lesion, and increased responses to other intensities two weeks after lesion. Furthermore, there was a decrease in ASR to 110 dB stimulus with 80 dB background noise two weeks after insular lesion. However, no significant difference was observed in 70 dB background noise. The changes in ASR lasts at least four weeks.Conclusion: The findings indicated that there was an increase in ASR in the absence of background noise following cortical excititoxic lesion limited to insular cortex, while there was a decrease in responses in the presence of background noise which suggests possible increased sensitivity to sound loudness as a hyperacusis-like phenomenon. The study showed a significant relationship between insular cortex lesion and ASR in rats.

The effect of age, gender and noise sensitivity on the liking of food in the presence of background noise

The liking of food in the presence of background noise has been associated with the noise type and level. So far, however, there have been few studies investigating the non-acoustic factors associated with food perception in the presence of background noise. This study investigated the food liking due to three non-acoustic factors (i.e. gender, noise sensitivity and age) in the presence of background noise, relative to the ambient background noise (i.e. no noise conditions). Fifteen participants rated the liking of food via questionnaires. The perceptual relative food liking due to age, gender and noise sensitivity at different noise types and levels were presented. The results indicated that age, noise sensitivity and gender influence relative food liking. Females had lower liking ratings of food than males (p = 0.038). Noise sensitivity was also negatively correlated with the relative liking of food (r = −0.72, p < 0.001). Sensitive participants gave lower relative food liking ratings (p = 0.023). The older participants also gave lower relative food liking ratings (p = 0.01). A better understanding of acoustic and non-acoustic factor effects on food perception can be an important area of interest in noise management of dining areas. These results also provide an opportunity for future practical and educational applications. These include a better service that could be presented from food providers and more practical acoustic design of dining areas to suit different groups of people.

Quantitative 3D Reconstructions of the Human Superior Olive Complex are Consistent with Auditory Dysfunction in Autism Spectrum Disorder

Beyond the characteristic social, communication and behavioral aberrations associated with autism spectrum disorder (ASD), the vast majority of subjects with this condition have some degree of auditory dysfunction. The auditory deficits range from complete deafness to hypersensitivity but typically include difficulty listening to speech in the presence of background noise. Clinical testing of brainstem evoked potentials and stapedial reflexes in children and adults with ASD reveal lower thresholds but slower conduction times and right‐left ear asymmetries. Previous studies on post‐mortem brain specimens from our lab revealed drastic and consistent hypoplasia and dysmorphology in the auditory brainstem. The most drastic alterations were found in the medial superior olive (MSO), the largest and most prominent component of the superior olivary complex (SOC). Our morphological studies have shown that in subjects with ASD, there are significantly fewer neurons in the MSO and surviving neurons are smaller, more round and have an abnormal orientation. Based on these results, we hypothesized that the SOC in subjects with ASD not only includes fewer neurons but that these nuclei occupy significantly less brain volume and demonstrate abnormal nuclear contours. We investigated this hypothesis by obtaining donated brain tissue from an age‐matched series of subjects with ASD or no known neurological diagnosis (neurotypical; NT) through Autism BrainNet. Free‐floating tissue sections were mounted onto glass slides, stained for Nissl substance with Giemsa and sealed under coverslips. 3D volume renderings of the SOC nuclei were created in Amira. Subjects in this study include two NT subjects (ages 4 and 8, both female) and four age‐matched subjects with ASD (ages 2–11 years of age, all male). At autopsy, there was no difference in total brain weight between NT and ASD subjects (p=.42). Our 3D reconstructions reveal a drastic reduction in the total volume of the SOC in subjects with ASD (control = 6.8 mm3, ASD = 2.23 mm3; p&lt;.005). In fact, all SOC nuclei were significantly smaller in ASD subjects expect for the ventral nucleus of the trapezoid body (p=.922). Together, these results support the brainstem as a core site of pathology in ASD and are consistent with previous clinical evaluations of hearing in subjects with ASD.Support or Funding InformationAutism BrainNet