Auditory Steady-state Response Research Articles (Page 1)

Brain oscillations are critical for neural communication and are increasingly recognized as sensitive biomarkers of neuropsychiatric dysfunction. Specifically, the auditory steady-state response (ASSR) has been identified as a reliable assessment of cortical entrainment and is a potential biomarker for the diagnosis or even prognosis of schizophrenia. Despite the growing awareness of sex as a biological variable, sex differences in oscillatory dynamics remain underexplored. Using electrophysiological recordings in mice, this study investigated sex differences in both spontaneous and evoked oscillatory brain activity under baseline conditions and following systemic NMDA receptor suppression via ketamine, a widely used pharmacological model of schizophrenia. Although spontaneous oscillations across a wide range of frequency bands did not differ significantly between sexes, male mice exhibited greater gamma-band entrainment at 40Hz ASSRs than females did. The administration of a subanaesthetic dose of ketamine consistently disrupted both spontaneous and gamma-band entrainment during ASSRs but without sex-specific effects. All measured oscillatory parameters showed high test‒retest reliability, thus indicating the robustness of the findings. Collectively, these results demonstrate sex-dependent differences in baseline cortical entrainment, highlighting the importance of including both sexes in preclinical research to fully elucidate the neurobiological mechanisms underlying brain oscillations and their implications in psychiatric disorders.

Prospective data analysis. The intraoperative measurement of auditory brainstem responses (ABR) enables the assessment of the coupling efficiency in active middle ear implant surgeries. Furthermore, auditory steady-state response (ASSR) measurements can offer additional frequency-specific evaluations. This study aims to examine the efficacy of intraoperative ASSR and ABR measurements and optimize implant placement during surgery. Tertiary referral center with an extensive active middle ear implant program. Main outcome measures: Intraoperative ABR and ASSR measurements were conducted using a standard ABR system and the AcoustiAP adapter. After the surgical procedure, vibrogram thresholds were measured. The statistical analysis determined correlations between intraoperative ASSR and ABR thresholds, preoperative bone conduction, and postoperative vibrogram thresholds. All patients underwent successful intraoperative recording of ABR and ASSR measurements. The ASSR thresholds exhibited a high correlation with bone conduction thresholds at 1000 Hz, 2000 Hz, and 4000 Hz. Furthermore, ASSR thresholds demonstrated robust correlations with postoperative vibrogram thresholds. Intraoperative ASSR measurements can provide valuable real-time feedback for ensuring optimal placement during implantation due to their good correlation with bone conduction. The high correlation between intraoperative ASSR and postoperative vibrogram thresholds indicates that ASSR can also assess postoperative hearing outcomes. Further development and implementation of these measurements in the clinical routine might improve surgical outcomes by enabling more precise frequency-specific assessments, improving both coupling efficiency and postoperative hearing results.

Do cognitive and neurophysiological effects of acute memantine "challenge" predict its clinical benefits in Alzheimer's Disease?

Background: Gamma-range auditory steady-state responses (ASSRs) are emerging as promising translational biomarkers of neural network function. While extensively studied in human neuropsychiatric and neurodevelopmental research, their application in animal models has expanded in recent years, providing mechanistic insights into disease-related neural dynamics. However, methodological approaches vary widely, findings remain fragmented, and outcomes are not easily generalized. Methods: A literature search was conducted in March 2025 across PubMed and Scopus to identify studies investigating gamma-range ASSRs (30–100 Hz) in animal models with relevance to psychiatric and developmental conditions. Results: Most studies employed rodents, with a smaller number involving non-human primates, and used pharmacological, genetic, lesion-based, or developmental manipulations relevant to schizophrenia, autism spectrum disorder, and related conditions. ASSRs were highly sensitive to NMDA receptor antagonism, state- and trait-related factors, and exhibited region- and layer-specific generation patterns centered on the auditory cortex. Less common paradigms, such as chirps and gap-in-noise, also demonstrated translational potential. Conclusions: Animal research confirms that gamma-range ASSRs provide a sensitive, cross-species readout of circuit dysfunctions observed in psychiatric and neurodevelopmental disorders. To maximize their translational utility, future work should prioritize methodological harmonization, systematic inclusion of sex and behavioral state factors, and replication across laboratories. Strengthening these aspects will enhance the value of ASSRs as biomarkers for early detection, patient stratification, and treatment monitoring in clinical psychiatry.

Abstract Background Sensorineural hearing loss (SNHL) poses a significant public health burden globally, with a disproportionately higher prevalence in developing regions like Africa. The consequences of SNHL in early childhood can be devastating, impacting speech, language, cognitive, and psychosocial development, ultimately affecting educational attainment and quality of life. The etiology of SNHL is multifactorial, encompassing genetic predispositions, prenatal and perinatal complications, infections, ototoxic insults, and environmental factors. In the African context, preventable causes such as congenital rubella, meningitis, mumps, and ototoxic medications play a significant role. Additionally, the high prevalence of consanguineous marriages and the lack of universal newborn hearing screening programs contribute to delayed diagnosis and interventions. Early and accurate diagnosis of SNHL is crucial for timely and appropriate medical, surgical, or audiological (re)habilitative measures. Main body However, the diagnosis of SNHL, particularly in children, can be challenging, necessitating a combination of audiological and radiological evaluations. Audiological assessments; behavioral measures (pure-tone audiometry [PTA]), electroacoustic measures (immittance audiometry and otoacoustic emissions), and electrophysiologic measures (auditory brainstem response and auditory steady-state response) are comprehensive audiological assessments which remain the cornerstone for identifying the site, degree, and laterality of hearing loss. They cannot localize or detect the underlying pathology, and this may affect the determination of appropriate interventions such as hearing aids, cochlear implants, other amplification devices, and other management options. Radiological imaging techniques, particularly computed tomography and magnetic resonance imaging, have revolutionized the evaluation of SNHL by providing detailed visualization of the intricate anatomy and pathologies of the bony and membranous labyrinths, respectively. Conclusion SNHL poses a significant challenge in the African context, with a higher burden and unique etiological patterns. Early and accurate diagnosis, facilitated by the integration of audiological and radiological evaluations, is crucial for timely interventions and optimal outcomes.

ASSR and ABR tests in early diagnosis of hearing loss: A STROBE observational study.

Auditory processing underlies phonological representation and presents neural oscillation lateralization in the brain. Atypical lateralization in auditory processing has been widely accepted as associated with impaired reading skills in alphabetic languages. However, whether Chinese adults with a reading difficulty (RD) history present atypical lateralization in auditory processing similar to that in alphabetic languages remains unknown. The purpose of this study was to investigate whether Chinese adults with poor reading would show atypical lateralization of neural oscillations during auditory sampling. Thirty-two adults with self-reported RD history and 44 adults without RD history were screened using the Chinese Adult Reading History Questionnaire. Reading accuracy, phonological accuracy, and rapid automatized naming (RAN) were assessed in all the participants. Auditory steady-state responses modulated at 10 to 80 Hz were recorded during a 5.4-sec white noise. Time-frequency power and phase synchrony indices were used to measure induced oscillatory power and synchrony of beta and gamma oscillations related to phonemic processing. Adults with a RD history performed worse than adults without RD history in reading accuracy and phonological accuracy. Adults with a RD history showed atypical rightward lateralization in the gamma band oscillation, whereas the adults without a RD history showed leftward lateralization. Adults with a RD history also demostrated reduced left-hemisphere oscillatory power and weaker bilateral synchrony. Event-related spectral perturbation in the left hemisphere correlated with reading accuracy in adults with RD history, while left-hemisphere lateralization of event-related spectral perturbation correlated with phonological accuracy in adults without RD history. In adults with RD history, the inter-trial phase synchrony in the left hemisphere correlated with RAN, and inter-trial phase synchrony in the right hemisphere correlated with reading accuracy and RAN, respectively. Adults with RD history demonstrated atypical rightward gamma band lateralization compared with adults without RD history, alongside reduced left-hemisphere oscillatory power and weaker bilateral synchrony. These neural patterns correlated with reading accuracy and phonological skills, supporting the hypothesis that auditory lateralization deficits underlie phonological processing challenges in Chinese, mirroring mechanisms observed in alphabetic languages.

SNRENN: A Transformer-Based Neural Network with Self-Supervised Learning for Auditory Steady State Response Signal SNR Enhancement

Auditory steady-state responses (ASSR) are available for frequency-dependent hearing threshold estimation in addition to the technique of conventional auditory brainstem responses (ABR). Although ABR and ASSR principally show strong correlations in hearing threshold estimation, there is preliminary evidence that temporal bone malformations might be associated with significantly greater differences between ABR- and ASSR-results. Therefore, the present study aimed to compare hearing threshold estimation derived from ABR and ASSR in a larger cohort of single-sided deafness (SSD) of various etiology, including temporal bone anomalies. The diagnostic consistency between ABR and ASSR using narrow-band-chirp-stimuli at 1000, 2000, and 4000Hz was analyzed in 47 children with single-sided deafness with varying MRI-morphologic findings: cochlear nerve malformation (CNM, n = 24), cochlear malformation (CM, n = 7) vs. combined malformation (CM + CNM, n = 8) vs. absent temporal bone and inner ear pathology (n = 8). Children with additional health issues other than SSD were excluded. ABR and ASSR showed a strong correlation in deaf ears without malformation (r = 0.728, p < 0.0001), a moderate correlation in isolated cochlear malformation (r = 0.574, p = 0.01), and a weak correlation in case of cochlear nerve anomaly (r = 0.189, p = 0.112 in CNM and r = 0.235, p = 0.268 in CM + CNM). Ears with isolated CNM showed an average discrepancy of 23.40 ± 15.19 dB, p < 0.00001 between ABR and ASSR (vs. 17.08 ± 15.81 dB, p = 0.0008 in CNM + CM, vs. 7.63 ± 8.56 dB, p = 0.008 in CM, vs. 4.38 ± 4.96 dB, p = 0.036 in ears without malformation and vs. 0.36 ± 4.75 dB, p = 0.748 in healthy control ears). In ears with highly discrepant ASSR and ABR values, enlarged ABR wave I and otoacoustic emissions were frequently present. In cochlear nerve malformation, ASSR and ABR frequently provide significantly discrepant hearing threshold estimations, probably derived from a cochlear origin. ASSR should only be used in conjunction with conventional ABR in the diagnostic management of suspected severe-profound hearing loss or deafness in children. A large difference between ASSR and ABR thresholds may indicate a cochlear nerve anomaly.

Broadband neural oscillatory dynamics at stimulus onset and offset during 40-Hz auditory stimulation.

Walking provides the motor foundation for navigation, while navigation ensures that walking is purposeful and adaptive to environmental contexts. Sensory processing of environmental information acts as the informational bridge that connects walking and adaptive navigation. In the current study, we assessed if walking and the walking direction influences neuronal dynamics underlying environmental information processing. To this end, we conducted two experiments with 12 male and 18 female participants while they walked along an 8-shaped path. Auditory entrainment stimuli were continuously presented, and mobile electroencephalogram was recorded. We found increased auditory entrainment (auditory steady-state response) and early auditory evoked responses during walking compared with standing or stepping in place. We also replicated the well-established reduction of occipital alpha power during walking. The increase of auditory entrainment and the decrease of alpha power were correlated across participants. In the second experiment, randomly presented transient burst sounds led to a perturbation of the auditory entrainment response. The perturbation response was stronger during walking compared with standing; however, only when the burst sounds were presented to one ear but not to both ears. Most importantly, we found that the auditory entrainment was systematically modulated dependent on the walking path. The entrainment responses changed as a function of the turning direction. In general, the current work shows that walking changes auditory processing in a walking path-dependent way which might serve to optimize navigation. The walking path-related modulation might further reflect a shift of attention, marking a form of higher-order active sensing.

The human auditory system must distinguish relevant sounds from noise. Severe hearing loss can be treated with cochlear implants (CIs), but how the brain adapts to electrical hearing remains unclear. This study examined adaptation to unilateral CI use in the first and seventh months after CI activation using speech comprehension measures and electroencephalography recordings, both during passive listening and an active spatial listening task. Neural phase-locking to amplitude-modulated sounds interacted with time, such that phase-locking longitudinally increased stronger for 40 Hz compared with 4 Hz. In the spatial listening task, the benefit of performing the task with the CI on vs. off was most pronounced when the CI ear was primarily exposed to target speech. Lateralized alpha oscillations (~10 Hz) reliably marked CI users’ focus of spatial attention. Stronger alpha modulation in the hemisphere opposite to the nonimplanted ear indicates an attentional bias toward the acoustically hearing ear. Our findings suggest that adaptation to hearing with a CI is accomplished by dynamic changes in auditory phase locking and a bias in auditory spatial attention.

Utility of auditory steady-state response in differentiating pediatric auditory neuropathy spectrum disorders: with normal auditory nerve diameter versus with auditory nerve hypoplasia.

Background:The aim is to quantify the electrode insertion trauma-induced hearing loss (EITHL), its risk factors, and its impact on speech outcomes in prelingually deafened children undergoing cochlear implantation.Methods:This was a prospective, observational study conducted at a single center between 2021 and 2024. Forty children aged 1–5 years with severe-to-profound sensorineural hearing loss underwent cochlear implantation using either the cochleostomy or round-window (RW) techniques. Auditory steady-state response (ASSR) thresholds were utilized to assess hearing preservation levels. Speech outcomes were evaluated by measuring word recognition scores (WRS) at 6, 12, and 24 months. The correlation between electrode insertion depth, hearing preservation, and speech outcomes was analyzed.Results:All participants achieved Grade 1 hearing preservation (>75%). The mean hearing preservation rates at 3, 6, 9, and 12 months were 93.2%, 92.3%, 92.9%, and 92.1%, respectively. Although the RWT demonstrated better hearing preservation than the CS technique, the difference was not statistically significant. A significant increase in low-frequency hearing thresholds was observed over time, with 12-month values of 84.9 ± 3.5 dB (250 Hz), 90.2 ± 3.7 dB (500 Hz), and 92.4 ± 4.0 dB (1000 Hz). A negative correlation was found between the depth of electrode insertion and hearing preservation (r = −0.45, P = .03). Word recognition scores improved over time, with bilateral implant recipients showing significantly higher scores (P < .00).Conclusion:Cochlear implantation via both CS and RW approaches preserves residual hearing in prelingually deafened children, with RW insertion demonstrating superior preservation. Deeper electrode insertion is associated with poorer hearing preservation, while better hearing preservation correlates with improved speech outcomes.

Background: Hearing loss is the most common sensory disorder in children, affecting 0.1 percent of newborns. The auditory brainstem response (ABR) test is the gold standard diagnostic test for infants who are unable to participate in behavioral testing. ABR is preferably performed under natural sleep (NS-ABR) to avoid risks associated with general anesthesia and sedation. However, if the infant wakes up during an NS-ABR, the test must be stopped and may need to be repeated later. Delays in diagnosis can place the child at higher risk for delays in cognitive and educational development. Purpose: We sought to understand factors that contribute to successful NS-ABR. Research Design: This was an exploratory mixed methods study to understand the barriers in obtaining an NS-ABR that is clinically sufficient for management. Study Sample: We performed a retrospective review of 0- to 12-month-old children who underwent NS-ABR. Data Collection and Analysis: For the quantitative approach, we studied 86 consecutive infants of 0‐12 months of age who underwent NS-ABR. For qualitative analysis, semistructured interviews and focus groups with audiologists were performed and analyzed using a thematic analysis approach. Results: Among the cohort of 86 infants, 164 NS-ABRs were performed. Sixty-three (73 percent) patients obtained a successful NS-ABR; only 65 (40 percent) of NS-ABRs were successful. The most common reasons for unsuccessful NS-ABR were poor sleep quality (n = 60/99, 61 percent), needing to “expand and confirm findings” (n = 26, 26 percent), and lack of or nonadherence to patient instructions (n = 27, 27 percent). Previous NS-ABR attempts and auditory steady-state response (ASSR) were significantly associated with successful NS-ABR (odds ratio [OR] = 1.46, 90 percent confidence interval [CI] = 1.13‐2.05; OR = 4.65, 90 percent CI = 1.70‐12.73, respectively). We identified four themes that impact success: inadequate logistical support for providers, inadequate emotional support for providers, providers juggling multiple tasks, and inadequate system scheduling flexibility. We triangulated these results to model interactions between factors that contribute to successful NS-ABR. Conclusions: NS-ABR is a diagnostic tool that can decrease patient exposure to sedation and anesthesia. This study suggests that individual, caregiver, provider, and systemic factors impact the success of NS-ABRs, especially for underserved populations. Multilevel interventions to improve success rates of NS-ABR would help decrease time from screening to diagnosis.

A strategy to predict psychotic risks of drug candidates using auditory steady-state response

Concurrent examination of gamma-stimulated variability in heart rate and auditory steady-state response in patients with major depressive, bipolar, and schizophrenia spectrum disorders.

Missing what's right under your nose: Failed appetitive and aversive audio-olfactory conditioning in humans.

In recent years, hybrid brain-computer interfaces (BCIs) have gained significant attention due to their demonstrated advantages in increasing the number of targets and enhancing robustness of the systems. However, Existing studies usually construct BCI systems using intense auditory stimulation and strong central visual stimulation, which lead to poor user experience and indicate a need for improving system comfort. Studies have proved that the use of peripheral visual stimulation and lower intensity of auditory stimulation can effectively boost the user's comfort. Therefore, this study used high-frequency peripheral visual stimulation and 40-dB weak auditory stimulation to elicit steady-state visual evoked potential (SSVEP) and auditory steady-state response (ASSR) signals, building a high-comfort hybrid BCI based on weak audio-visual evoked responses. This system coded 40 targets via 20 high-frequency visual stimulation frequencies and two auditory stimulation frequencies, improving the coding efficiency of BCI systems. Results showed that the hybrid system's averaged classification accuracy was (78.00 ± 12.18) %, and the information transfer rate (ITR) could reached 27.47 bits/min. This study offers new ideas for the design of hybrid BCI paradigm based on imperceptible stimulation.

Two EEG-responses to periodical auditory 40-Hz stimulation – auditory steady-state response (ASSR) and sustained wave (SW) – are important neurophysiological correlates of temporal and spectral aspects of auditory perception, respectively. However, little is known about the sex difference of their development in children of 3–6 years, the period of extensive language acquisition. We registered a 32-channel electroencephalogram (EEG) while 500-ms 40-Hz click trains (n = 150) were presented to 57 typically developing children (27 females). We also assessed total language skill, expressive and receptive speech abilities, the perception of speech in noise and pseudowords repetition. 40-Hz ASSR was not very clearly expressed in our sample but showed developmental increase for both boys and girls. Topography of SW showed significant right-hemisphere predominance in boys, while girls had more symmetric response. On a subsample of boys (n = 14) we also found that the laterality index of SW correlated with speech in noise repetition score: the greater rightwarded the laterality was, the worse boys repeated words in noise. Our results are also consistent with the findings of greater lateralization of some components of EEG-activity in men.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-08266-x.