Masking Conditions Research Articles

Effect of Level and Frequency of Forward Masker on Auditory Brainstem Response.

Forward masking (FM) is characterized by the perception of a signal being reduced or wholly masked due to a preceding sound (masker) of the same or different frequencies that offers a challenge for the auditory system to resolve. Considering that the off-frequency masker is expected to undergo linear processing compared to the on-frequency masker at the signal place, it reflects the peripheral auditory systems' compressive response. Thus, the present study focused on employing FM electrophysiological analogous such as auditory brainstem responses (ABR) to the behavioral masking experiments to objectively measure the frequency and level of processing in the auditory system, from the periphery to the brainstem level. The study was an observational research on 21 female volunteers. ABR was obtained using a tone-on-tone FM paradigm for 1000- and 4000-Hz probe stimuli. An experiment used two forward maskers, on-frequency and off-frequency, with varying levels from 50 to 70 dB SPL. A progressive shift for Vth peak latency and reduction in response amplitude was observed in proportion to the increase of masker level for both the probe stimuli and the masking experiments. However, ABR responses in neither masking condition were observed to differ between 60 and 70 dB SPL. FM ABR experiments are an assessment tool for estimating frequency and level processing in the auditory system, providing good efficiency, reliability, and less subject bias compared to behavioral measures.

Active noise-cancelling headphones do not improve cognitive performance in office noise environment

Our purpose was to determine the influence of different use settings of on-ear ANC (active noise-cancelling) headphones on performance, experience, and physiological stress in conditions resembling an office where task irrelevant speech is present. Laboratory experiment involved 54 participants, who were exposed to five conditions: 1. No headphones, 2. Headphones without ANC operation, 3. Headphones with ANC operation, 4. Headphones with sound masking playback, 5. Headphones with ANC operation and sound masking playback. In all conditions, speech was present in the room at 52 dB LAeq. Masking was 51 dB LAeq wideband noise played from the headphones. Participants' performance was measured with visual serial recall and 3-back tasks, and physiological stress with heart rate variability. The condition did not influence performances nor physiological stress. The only effects of sound condition were observed in subjective experiences. With masking (conditions 4 and 5), the speech was less annoying than without the headphones (condition 1). Sound environment was estimated to impair performance and disturb concentration less than without the headphones only in condition 5. Therefore, using headphones together with masking and ANC function can improve experience. Using headphones with ANC function alone did not improve performance nor reduce stress level.

"Hot" affect-related aspects in emotional information processing: The role of facial muscle responses in the direct and indirect processing of emotion categories.

The present study investigated the involvement of facial muscle responses in the indirect and direct processing of emotional facial expressions. Five discrete emotion categories were used, and we assessed both facial muscle and behavioral responses on a trial-by-trial basis. Experiment 1 tested facial muscle activation of clearly visible stimuli in an emotion categorization task. We observed emotion-specific facial muscle responses and corresponding behavioral categorization effects, providing evidence for the specificity of facial muscle activation. By contrast, under masked indirect presentation conditions in which emotional facial expressions were presented as primes in an emotion misattribution procedure, a specific pattern of emotion-congruent and cross-category behavioral misattributions was observed (in line with Rohr et al., 2015, 2018). Multilevel analyses in Study 2 suggest that an emotional reaction feeds into the behavioral decision, as indicated by differential activation of the frontalis lateralis in response to angry faces. Thus, the present study provides evidence that facial muscle responses contribute to behavioral decisions under masked indirect processing conditions. The different pattern of effects in both studies suggests that facial muscle responses index different processes, depending on the processing conditions: sensorimotor simulation in direct processing conditions and emotional reactions in masked indirect processing conditions. We discuss the implications for models that aim to account for facial muscle activity in response to emotional facial expressions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Masking Effects Caused by Contralateral Distractors in Participants With Versus Without Listening Difficulties

Objectives: To examine the effects of distractor sounds presented to the contralateral ear on speech intelligibility in patients with listening difficulties without apparent peripheral pathology and in control participants. Design: This study examined and analyzed 15 control participants (age range, 22 to 30 years) without any complaints of listening difficulties and 15 patients (age range, 15 to 33 years) diagnosed as having listening difficulties without apparent peripheral pathology in the outpatient clinic of the Department of Otolaryngology-Head and Neck Surgery, Tohoku University Hospital. Speech intelligibility for 50 Japanese monosyllables presented to the right ear was examined under the following three different conditions: “without contralateral sound,” “with continuous white noise in the contralateral ear,” and “with music stimuli in the contralateral ear.” Results: The results indicated the following: (1) speech intelligibility was significantly worse in the patient group with contralateral music stimuli and noise stimuli; (2) speech intelligibility was significantly worse with contralateral music stimuli than with contralateral noise stimuli in the patient group; (3) there was no significant difference in speech intelligibility among three contralateral masking conditions (without contra-stimuli, with contra-noise, and with contra-music) in the control group, although average and median values of speech intelligibility tended to be worse with contralateral music stimuli than without contralateral stimuli. Conclusions: Significantly larger masking effects due to a contralateral distractor sound observed in patients with listening difficulties without apparent peripheral pathology may suggest the possible involvement of masking mechanisms other than the energetic masking mechanism occurring in the periphery in these patients. In addition, it was also shown that the masking effect is more pronounced with real environmental sounds, that is, music with lyrics, than with continuous steady noise, which is often used as a masker for speech-in-noise testing in clinical trials. In other words, it should be noted that a speech-in-noise test using such steady noise may underestimate the degree of listening problems of patients with listening difficulties in their daily lives, and a speech-in-noise test using a masker such as music and/or speech sounds could make listening problems more obvious in patients with listening difficulties.

Efficacy of a novel oxygen scavenger mask in reducing local oxygen concentrations below the surgical fire risk threshold: an experimental proof-of-concept study

BackgroundThis study aims to evaluate the efficacy of an oxygen scavenging mask device in reducing local oxygen concentrations from nasal cannula ventilation compared to a standard open facial surgical field.MethodsThis is a controlled experiment using a custom-fabricated silicone midfacial oxygen scavenging device, SimMan airway management trainer manikin (Laerdal Medical, Stavanger, Norway), handheld oxygen detector (Forensics Detectors, Los Angeles, United States) and oxygen from a Datex Ohmeda Aisys Carestation anesthesia unit (GE HealthCare, Chicago, United States). Oxygen concentrations were measured at 18 facial landmarks (Fig. 1) with nasal cannula flow of 2, 4, and 6 L/min of 100% FiO2 in both masked and unmasked conditions (Fig. 2).ResultsThe mean oxygen concentration in the facial surgical field was 20.95% with the scavenger mask and 24.8% without (P < 0.001; two-tailed paired t-test). The unmasked condition was associated with suprathreshold oxygen concentration levels at 13 of 18 facial landmarks (Table 1). The device significantly reduced local oxygen concentration at 16 of 18 facial landmarks (Table 1). The device provided safe oxygen concentration levels at all three flow rates, and measured oxygen concentrations directly correlated with oxygen flow rate in the unmasked condition (Table 2).ConclusionsAn oxygen scavenger mask device reduced local oxygen concentrations from nasal cannula ventilation to below the 23% fire threshold in the entire facial surgical field external to the mask in these experiments. The device may reduce intraoperative fire risk in patients that require supplementary oxygen during surgery.

Impact of Reverberation on Speech Perception in Noise in Bimodal/Bilateral Cochlear Implant Users with and without Residual Hearing.

(1) Background: The aim of the present study was to assess the impact of reverberation on speech perception in noise and spatial release from masking (SRM) in bimodal or bilateral cochlear implant (CI) users and CI subjects with low-frequency residual hearing using combined electric-acoustic stimulation (EAS). (2) Methods: In total, 10 bimodal, 14 bilateral CI users and 14 EAS users, and 17 normal hearing (NH) controls, took part in the study. Speech reception thresholds (SRTs) in unmodulated noise were assessed in co-located masker condition (S0N0) with a spatial separation of speech and noise (S0N60) in both free-field and loudspeaker-based room simulation for two different reverberation times. (3) Results: There was a significant detrimental effect of reverberation on SRTs and SRM in all subject groups. A significant difference between the NH group and all the CI/EAS groups was found. There was no significant difference in SRTs between any CI and EAS group. Only NH subjects achieved spatial release from masking in reverberation, whereas no beneficial effect of spatial separation of speech and noise was found in any CI/EAS group. (4) Conclusions: The subject group with electric-acoustic stimulation did not yield a superior outcome in terms of speech perception in noise under reverberation when the noise was presented towards the better hearing ear.

Auditory confounds can drive online effects of transcranial ultrasonic stimulation in humans.

Transcranial ultrasonic stimulation (TUS) is rapidly emerging as a promising non-invasive neuromodulation technique. TUS is already well-established in animal models, providing foundations to now optimize neuromodulatory efficacy for human applications. Across multiple studies, one promising protocol, pulsed at 1000 Hz, has consistently resulted in motor cortical inhibition in humans (Fomenko et al., 2020). At the same time, a parallel research line has highlighted the potentially confounding influence of peripheral auditory stimulation arising from TUS pulsing at audible frequencies. In this study, we disentangle direct neuromodulatory and indirect auditory contributions to motor inhibitory effects of TUS. To this end, we include tightly matched control conditions across four experiments, one preregistered, conducted independently at three institutions. We employed a combined transcranial ultrasonic and magnetic stimulation paradigm, where TMS-elicited motor-evoked potentials (MEPs) served as an index of corticospinal excitability. First, we replicated motor inhibitory effects of TUS but showed through both tight controls and manipulation of stimulation intensity, duration, and auditory masking conditions that this inhibition was driven by peripheral auditory stimulation, not direct neuromodulation. Furthermore, we consider neuromodulation beyond driving overall excitation/inhibition and show preliminary evidence of how TUS might interact with ongoing neural dynamics instead. Primarily, this study highlights the substantial shortcomings in accounting for the auditory confound in prior TUS-TMS work where only a flip-over sham and no active control was used. The field must critically reevaluate previous findings given the demonstrated impact of peripheral confounds. Furthermore, rigorous experimental design via (in)active control conditions is required to make substantiated claims in future TUS studies. Only when direct effects are disentangled from those driven by peripheral confounds can TUS fully realize its potential for research and clinical applications.

Auditory confounds can drive online effects of transcranial ultrasonic stimulation in humans

Transcranial ultrasonic stimulation (TUS) is rapidly emerging as a promising non-invasive neuromodulation technique. TUS is already well-established in animal models, providing foundations to now optimize neuromodulatory efficacy for human applications. Across multiple studies, one promising protocol, pulsed at 1000 Hz, has consistently resulted in motor cortical inhibition in humans (Fomenko et al., 2020). At the same time, a parallel research line has highlighted the potentially confounding influence of peripheral auditory stimulation arising from TUS pulsing at audible frequencies. In this study, we disentangle direct neuromodulatory and indirect auditory contributions to motor inhibitory effects of TUS. To this end, we include tightly matched control conditions across four experiments, one preregistered, conducted independently at three institutions. We employed a combined transcranial ultrasonic and magnetic stimulation paradigm, where TMS-elicited motor-evoked potentials (MEPs) served as an index of corticospinal excitability. First, we replicated motor inhibitory effects of TUS but showed through both tight controls and manipulation of stimulation intensity, duration, and auditory masking conditions that this inhibition was driven by peripheral auditory stimulation, not direct neuromodulation. Furthermore, we consider neuromodulation beyond driving overall excitation/inhibition and show preliminary evidence of how TUS might interact with ongoing neural dynamics instead. Primarily, this study highlights the substantial shortcomings in accounting for the auditory confound in prior TUS-TMS work where only a flip-over sham and no active control was used. The field must critically reevaluate previous findings given the demonstrated impact of peripheral confounds. Furthermore, rigorous experimental design via (in)active control conditions is required to make substantiated claims in future TUS studies. Only when direct effects are disentangled from those driven by peripheral confounds can TUS fully realize its potential for research and clinical applications.

Localization of Moving Sound Stimuli under Conditions of Spatial Masking

The aim of this study was to investigate spatial masking of noise signals in the delayed motion paradigm. Spatial effects were created by interaural level differences (ILD). Stationary maskers were located laterally or near the head midline, while test signals moved at different velocities from the head midline towards the ears, or in the opposite direction. The masking effect was measured by shifts in the perceived azimuthal positions of the starting and final points of signal trajectories, compared to their positions in silence. The perceived trajectories of all test signals shifted in the opposite direction from the masker. The masking effect was most pronounced in the spatial regions closest to the maskers, and was stronger when the signal moved towards the masker, compared to moving away from it. The final points were perceptually shifted further than the starting points. Signal velocity and masker presentation side (left or right) did not change the degree of masking.

Learning effects in speech-in-noise tasks: Effect of masker modulation and masking release.

Previous research has shown that learning effects are present for speech intelligibility in temporally modulated (TM) noise, but not in stationary noise. The present study aimed to gain more insight into the factors that might affect the time course (the number of trials required to reach stable performance) and size [the improvement in the speech reception threshold (SRT)] of the learning effect. Two hypotheses were addressed: (1) learning effects are present in both TM and spectrally modulated (SM) noise and (2) the time course and size of the learning effect depend on the amount of masking release caused by either TM or SM noise. Eighteen normal-hearing adults (23-62 years) participated in SRT measurements, in which they listened to sentences in six masker conditions, including stationary, TM, and SM noise conditions. The results showed learning effects in all TM and SM noise conditions, but not for the stationary noise condition. The learning effect was related to the size of masking release: a larger masking release was accompanied by an increased time course of the learning effect and a larger learning effect. The results also indicate that speech is processed differently in SM noise than in TM noise.

French version of the coordinate response measure corpus and its validation on a speech-on-speech task.

Since its creation, the coordinate response measure (CRM) corpus has been applied in hundreds of studies to explore the mechanisms of informational masking in multi-talker situations, but also in speech-in-noise or auditory attentional tasks. Here, we present its French version, with equivalent content to the original version in English. Furthermore, an evaluation of speech-on-speech intelligibility in French shows informational masking with similar result patterns to the original data in English. This validation of the French CRM corpus allows to propose the use of the CRM for intelligibility tests in French, and for comparisons with a foreign language under masking conditions.

The role of long-term target and masker talker familiarity in children's speech-in-speech recognition.

This study investigated the influence of long-term talker familiarity on speech-in-speech recognition in school-age children, with a specific emphasis on the role of familiarity with the mother's voice as either the target or masker speech. Open-set sentence recognition was measured adaptively in a two-talker masker. Target and masker sentences were recorded by the adult mothers of the child participants. Each child heard sentences spoken by three adult female voices during testing; their own mother's voice (familiar voice) and two unfamiliar adult female voices. Twenty-four school age children (8-13 years) with normal hearing. When the target speech was spoken by a familiar talker (the mother), speech recognition was significantly better compared to when the target was unfamiliar. When the masker was spoken by the familiar talker, there was no difference in performance relative to the unfamiliar masker condition. Across all conditions, younger children required a more favorable signal-to-noise ratio than older children. Implicit long-term familiarity with a talker consistently improves children's speech-in-speech recognition across the age range tested, specifically when the target talker is familiar. However, performance remains unaffected by masker talker familiarity. Additionally, while target familiarity is advantageous, it does not entirely eliminate children's increased susceptibility to competing speech.

Fast saccades to faces during the feedforward sweep.

Saccadic choice tasks use eye movements as a response method, typically in a task where observers are asked to saccade as quickly as possible to an image of a prespecified target category. Using this approach, face-selective saccades have been observed within 100ms poststimulus. When taking into account oculomotor processing, this suggests that faces can be detected in as little as 70 to 80ms. It has therefore been suggested that face detection must occur during the initial feedforward sweep, since this latency leaves little time for feedback processing. In the current experiment, we tested this hypothesis using backward masking-a technique shown to primarily disrupt feedback processing while leaving feedforward activation relatively intact. Based on minimum saccadic reaction time, we found that face detection benefited from ultra-fast, accurate saccades within 110 to 160ms and that these eye movements are obtainable even under extreme masking conditions that limit perceptual awareness. However, masking did significantly increase the median SRT for faces. In the manual responses, we found remarkable detection accuracy for faces and houses, even when participants indicated having no visual experience of the test images. These results provide evidence for the view that the saccadic bias to faces is initiated by coarse information used to categorize faces in the feedforward sweep but that, in most cases, additional processing is required to quickly reach the threshold for saccade initiation.

Investigating the impact of surgical masks on behavioral reactions to facial emotions in the COVID-19 era.

The widespread use of surgical masks during the COVID-19 pandemic has posed challenges in interpreting facial emotions. As the mouth is known to play a crucial role in decoding emotional expressions, its covering is likely to affect this process. Recent evidence suggests that facial expressions impact behavioral responses only when their emotional content is relevant to subjects' goals. Thus, this study investigates whether and how masked emotional faces alter such a phenomenon. Forty participants completed two reaching versions of the Go/No-go task in a counterbalanced fashion. In the Emotional Discrimination Task (EDT), participants were required to respond to angry, fearful, or happy expressions by performing a reaching movement and withholding it when a neutral face was presented. In the Gender Discrimination Task (GDT), the same images were shown, but participants had to respond according to the poser's gender. The face stimuli were presented in two conditions: covered by a surgical mask (masked) or without any covering (unmasked). Consistent with previous studies, valence influenced behavioral control in the EDT but not in the GDT. Nevertheless, responses to facial emotions in the EDT exhibited significant differences between unmasked and masked conditions. In the former, angry expressions led to a slowdown in participants' responses. Conversely, in the masked condition, behavioral reactions were impacted by fearful and, to a greater extent, by happy expressions. Responses to fearful faces were slower, and those to happy faces exhibited increased variability in the masked condition compared to the unmasked condition. Furthermore, response accuracy to masked happy faces dramatically declined compared to the unmasked condition and other masked emotions. In sum, our findings indicate that surgical masks disrupt reactions to emotional expressions, leading people to react less accurately and with heightened variability to happy expressions, provided that the emotional dimension is relevant to people's goals.

Influencing assessment of mask wearing on thermal comfort and pleasure during outdoor walking in hot summer region

Face masks are normally used by ones who work /walk outdoors to protect them away from air pollutants, for instance, traffic police, but the impact on the outdoor thermal perception is rarely reported in high-density cities during extreme hot summer. This study aims to explore the effect of face mask wearing on subjects' thermal perceptions with walking in Shanghai during summer. 796 valid questionnaires with environmental measurement and physiological parameter are collected respectively under the condition of with and without wearing surgical face masks. Results point out that subjects show higher thermal sensation, exertion, and lower thermal comfort as well as pleasure when they put on face masks, and a negative effect exists on the recovery of subjects' physiological parameters and perceptions after walking. Subjects wearing face masks are more prone to thermal stress, as they feel hot at the physiological equivalent temperature (PET) value of 52.4 °C in no masking condition, but 48.6 °C in masking condition. Meanwhile, subjects respond less thermal comfort in hot outsides with face masks even in slow walking. The research finally proposes an assessing range of thermal perceptions with activities for PET to better understand outdoor thermal comfort in mask wearing conditions during hot summer.

Measuring and modeling Gaussian noise disruption across frequency, level, and hearing status

Recent work suggested that older listeners with minimal hearing loss exhibit more forward masking for a highly fluctuating Gaussian noise (GN) masker relative to a low-fluctuation noise (LFN) masker. This threshold difference (GN–LFN) is referred to as GN disruption and was previously attributed to time-varying cochlear gain resulting from feedback control by the medial olivocochlear (MOC) system. However, thus far, masker conditions have been limited to 80 dB SPL at 4 kHz. The current study aims to challenge the hypothesis that the physiological basis of GN disruption is the MOC system using behavioral measures and computational models across multiple target and masker frequencies (0.5, 1, 2, and 4 kHz), masker levels (80-, 65-, and 50-dB SPL), masker-signal delays (25- and 75-ms), participant age ranges (18–30 and 60–75), and hearing statuses (normal hearing, sensorineural hearing loss). Additionally, speech recognition using IEEE sentences will be measured with GN and LFN maskers. Although testing will not be completed until 2025, preliminary data from 20 younger participants with normal hearing suggest that GN disruption is greater for higher than lower masker and probe frequencies, that GN disruption is similar across masker levels, and that refinements to the computational model are needed to more accurately predict GN disruption.

Accuracy and Speed of Emotion Recognition With Face Masks.

Wearing face masks is one of the important actions to prevent the spread of COVID-19 among people around the world. Nevertheless, social interaction is limited via masks, and this impacts the accuracy and speed of emotional perception. In the present study, we assess the impact of mask-wearing on the accuracy and speed of emotion recognition. Fifty people (female n = 39, male n = 11) aged 19-28 participated in the study (M = 21.1 years). We used frontal photos of a Kosova woman who belonged to the same participants' age group, with a grey background. Twelve different pictures were used that showed the emotional states of fear, joy, sadness, anger, neutrality, and disgust, in masked and unmasked conditions. The experiment was conducted in a controlled laboratory setting. Participants were faster for identifying emotions like joy (1.507 ms) and neutral (1.971 ms). The participants were more accurate (emotions identification) in unmasked faces (M = 85.7%) than in masked faces (M = 73.8%), F(1,98) = 20.73, MSE = 1027.66, p ≤ .001, partial η² = 0.17. Masks make confusion and reduce the accuracy and speediness of emotional detection. This may have a notable impact on social interactions among peoples.

Development of the Children's English and Spanish Speech Recognition Test: Psychometric Properties, Feasibility, Reliability, and Normative Data.

The Children's English and Spanish Speech Recognition (ChEgSS) test is a computer-based tool for assessing closed-set word recognition in English and in Spanish, with a masker that is either speech-shaped noise or competing speech. The present study was conducted to (1) characterize the psychometric properties of the ChEgSS test, (2) evaluate feasibility and reliability for a large cohort of Spanish/English bilingual children with normal hearing, and (3) establish normative data. Three experiments were conducted to evaluate speech perception in children (4-17 years) and adults (19-40 years) with normal hearing using the ChEgSS test. In Experiment 1, data were collected from Spanish/English bilingual and English monolingual adults at multiple, fixed signal-to-noise ratios. Psychometric functions were fitted to the word-level data to characterize variability across target words in each language and in each masker condition. In Experiment 2, Spanish/English bilingual adults were tested using an adaptive tracking procedure to evaluate the influence of different target-word normalization approaches on the reliability of estimates of masked-speech recognition thresholds corresponding to 70.7% correct word recognition and to determine the optimal number of reversals needed to obtain reliable estimates. In Experiment 3, Spanish/English bilingual and English monolingual children completed speech perception testing using the ChEgSS test to (1) characterize feasibility across age and language group, (2) evaluate test-retest reliability, and (3) establish normative data. Experiments 1 and 2 yielded data that are essential for stimulus normalization, optimizing threshold estimation procedures, and interpreting threshold data across test language and masker type. Findings obtained from Spanish/English bilingual and English monolingual children with normal hearing in Experiment 3 support feasibility and demonstrate reliability for use with children as young as 4 years of age. Equivalent results for testing in English and Spanish were observed for Spanish/English bilingual children, contingent on adequate proficiency in the target language. Regression-based threshold norms were established for Spanish/English bilingual and English monolingual children between 4 and 17 years of age. The present findings indicate the ChEgSS test is appropriate for testing a wide age range of children with normal hearing in either Spanish, English, or both languages. The ChEgSS test is currently being evaluated in a large cohort of patients with hearing loss at pediatric audiology clinics across the United States. Results will be compared with normative data established in the present study and with established clinical measures used to evaluate English- and Spanish-speaking children. Questionnaire data from parents and clinician feedback will be used to further improve test procedures.

Evoked Brain Potentials to Sound Offset in Humans in Conditions of Spatial Masking

Evoked Brain Potentials to Sound Offset in Humans in Conditions of Spatial Masking

Estimation of Cochlear Frequency Selectivity Using a Convolution Model of Forward-Masked Compound Action Potentials.

Frequency selectivity is a fundamental property of the peripheral auditory system; however, the invasiveness of auditory nerve (AN) experiments limits its study in the human ear. Compound action potentials (CAPs) associated with forward masking have been suggested as an alternative to assess cochlear frequency selectivity. Previous methods relied on an empirical comparison of AN and CAP tuning curves in animal models, arguably not taking full advantage of the information contained in forward-masked CAP waveforms. To improve the estimation of cochlear frequency selectivity based on the CAP, we introduce a convolution model to fit forward-masked CAP waveforms. The model generates masking patterns that, when convolved with a unitary response, can predict the masking of the CAP waveform induced by Gaussian noise maskers. Model parameters, including those characterizing frequency selectivity, are fine-tuned by minimizing waveform prediction errors across numerous masking conditions, yielding robust estimates. The method was applied to click-evoked CAPs at the round window of anesthetized chinchillas using notched-noise maskers with various notch widths and attenuations. The estimated quality factor Q10 as a function of center frequency is shown to closely match the average quality factor obtained from AN fiber tuning curves, without the need for an empirical correction factor. This study establishes a moderately invasive method for estimating cochlear frequency selectivity with potential applicability to other animal species or humans. Beyond the estimation of frequency selectivity, the proposed model proved to be remarkably accurate in fitting forward-masked CAP responses and could be extended to study more complex aspects of cochlear signal processing (e.g., compressive nonlinearities).