Improved Speech Understanding Research Articles

Cochlear Implantation in Children with Postlingual Progressive Steeply Sloping High-Frequency Hearing Loss.

Children with steeply sloping sensorineural hearing loss (SNHL) lack access to critical high-frequency cues despite the use of advanced hearing aid technology. In addition, their auditory-only aided speech perception abilities often meet Food and Drug Administration criteria for cochlear implantation. The objective of this study was to describe hearing preservation and speech perception outcomes in a group of young children with steeply sloping SNHL who received a cochlear implant (CI). Retrospective case series. Eight children with steeply sloping postlingual progressive SNHL who received a unilateral traditional CI at Seattle Children's Hospital between 2009 and 2013 and had follow-up data available up to 24 mo postimplant were included. A retrospective chart review was completed. Medical records were reviewed for demographic information, preoperative and postoperative behavioral hearing thresholds, and speech perception scores. Paired t tests were used to analyze speech perception data. Hearing preservation results are reported. Rapid improvement of speech perception scores was observed within the first month postimplant for all participants. Mean monosyllabic word scores were 76% and mean phoneme scores were 86.7% at 1-mo postactivation compared to mean preimplant scores of 19.5% and 31.0%, respectively. Hearing preservation was observed in five participants out to 24-mo postactivation. Two participants lost hearing in both the implanted and unimplanted ear, and received a sequential bilateral CI in the other ear after progression of the hearing loss. One participant had a total loss of hearing in only the implanted ear. Results reported in this article are from the ear implanted first. Bilateral outcomes are not reported. CIs provided benefit for children with steeply sloping bilateral hearing loss for whom hearing aids did not provide adequate auditory access. In our cohort, significant improvements in speech understanding occurred rapidly postactivation. Preservation of residual hearing in children with a traditional CI electrode is possible.

Speech Understanding in Complex Listening Environments by Listeners Fit With Cochlear Implants

The aim of this article is to summarize recent published and unpublished research from our 2 laboratories on improving speech understanding in complex listening environments by listeners fit with cochlear implants (CIs). CI listeners were tested in 2 listening environments. One was a simulation of a restaurant with multiple, diffuse noise sources, and the other was a cocktail party with 2 spatially separated point sources of competing speech. At issue was the value of the following sources of information, or interventions, on speech understanding: (a) visual information, (b) adaptive beamformer microphones and remote microphones, (c) bimodal fittings, that is, a CI and contralateral low-frequency acoustic hearing, (d) hearing preservation fittings, that is, a CI with preserved low-frequency acoustic in the same ear plus low-frequency acoustic hearing in the contralateral ear, and (e) bilateral CIs. A remote microphone provided the largest improvement in speech understanding. Visual information and adaptive beamformers ranked next, while bimodal fittings, bilateral fittings, and hearing preservation provided significant but less benefit than the other interventions or sources of information. Only bilateral CIs allowed listeners high levels of speech understanding when signals were roved over the frontal plane. The evidence supports the use of bilateral CIs and hearing preservation surgery for best speech understanding in complex environments. These fittings, when combined with visual information and microphone technology, should lead to high levels of speech understanding by CI patients in complex listening environments. http://cred.pubs.asha.org/article.aspx?articleid=2601622.

Cochlear Implantation in the Elderly: Review on the Clinical Effectiveness

The aim of this review is to identify relevant literature reports on cochlear implantation in the elderly population; to compare the outcome of hearing rehabilitation in elderly versus younger adult cochlear implant recipients; to review reported surgical complications; to analyze possible predictive factors; and to evaluate the health-related quality of life. All elderly cohorts had a significant improvement in speech understanding and a positive impact on quality of life after cochlear implantation without an increased surgical risk. It was irrelevant if elderly was defined at the age of 60 or 80 years. Complex hearing tasks, such as hearing in background noise, may require a longer time for comprehension, and in general, the elderly population requires longer auditory therapy than the younger counterparts. Duration of deafness seems to be the most redundant predictive factor supported in most studies. Cochlear implantation candidacy in elderly patients must be made on an individual basis, dependent on overall health as well as cognitive status. Advanced age alone is not a contraindication when determining candidacy for cochlear implantation.

Physiological Mechanisms in Combined Electric-Acoustic Stimulation.

Electrical stimulation is normally performed on ears that have no hearing function, i.e., lack functional hair cells. The properties of electrically-evoked responses in these cochleae were investigated in several previous studies. Recent clinical developments have introduced cochlear implantation (CI) in residually-hearing ears to improve speech understanding in noise. The present study documents the known physiological differences between electrical stimulation of hair cells and of spiral ganglion cells, respectively, and reviews the mechanisms of combined electric and acoustic stimulation in the hearing ears. Literature review from 1971 to 2016. Compared with pure electrical stimulation the combined electroacoustic stimulation provides additional low-frequency information and expands the dynamic range of the input. Physiological studies document a weaker synchronization of the evoked activity in electrically stimulated hearing ears compared with deaf ears that reduces the hypersynchronization of electrically-evoked activity. The findings suggest the possibility of balancing the information provided by acoustic and electric input using stimulus intensity. Absence of distorting acoustic-electric interactions allows exploiting these clinical benefits of electroacoustic stimulation.

Speech Understanding in Noise by Patients With Cochlear Implants Using a Monaural Adaptive Beamformer.

The aim of this experiment was to compare, for patients with cochlear implants (CIs), the improvement for speech understanding in noise provided by a monaural adaptive beamformer and for two interventions that produced bilateral input (i.e., bilateral CIs and hearing preservation [HP] surgery). Speech understanding scores for sentences were obtained for 10 listeners fit with a single CI. The listeners were tested with and without beamformer activated in a "cocktail party" environment with spatially separated target and maskers. Data for 10 listeners with bilateral CIs and 8 listeners with HP CIs were taken from Loiselle, Dorman, Yost, Cook, and Gifford (2016), who used the same test protocol. The use of the beamformer resulted in a 31 percentage point improvement in performance; in bilateral CIs, an 18 percentage point improvement; and in HP CIs, a 20 percentage point improvement. A monaural adaptive beamformer can produce an improvement in speech understanding in a complex noise environment that is equal to, or greater than, the improvement produced by bilateral CIs and HP surgery.

The use of cochlear's SCAN and wireless microphones to improve speech understanding in noise with the Nucleus6® CP900 processor

Objectives: The newest Nucleus CI processor, the CP900, has two new options to improve speech-in-noise perception: (1) use of an adaptive directional microphone (SCAN mode) and (2) wireless connection to MiniMic1 and MiniMic2 wireless remote microphones. Design: An analysis was made of the absolute and relative benefits of these technologies in a real-world mimicking test situation. Speech perception was tested using an adaptive speech-in-noise test (sentences-in-babble noise). In session A, SRTs were measured in three conditions: (1) Clinical Map, (2) SCAN and (3) MiniMic1. Each was assessed for three distances between speakers and CI recipient: 1 m, 2 m and 3 m. In session B, the benefit of the use of MiniMic2 was compared to benefit of MiniMic1 at 3 m. Study sample: A group of 13 adult CP900 recipients participated. Results: SCAN and MiniMic1 improved performance compared to the standard microphone with a median improvement in SRT of 2.7–3.9 dB for SCAN at 1 m and 3 m, respectively, and 4.7–10.9 dB for the MiniMic1. MiniMic1 improvements were significant. MiniMic2 showed an improvement in SRT of 22.2 dB compared to 10.0 dB for MiniMic1 (3 m). Conclusions: Digital wireless transmission systems (i.e. MiniMic) offer a statistically and clinically significant improvement in speech perception in challenging, realistic listening conditions.

The effects of early auditory-based intervention on adult bilateral cochlear implant outcomes

Objectives: The goal of this exploratory study was to determine the types of improvement that sequentially implanted auditory-verbal and auditory-oral adults with prelingual and childhood hearing loss received in bilateral listening conditions, compared to their best unilateral listening condition.Methods: Five auditory-verbal adults and five auditory-oral adults were recruited for this study. Participants were seated in the center of a 6-loudspeaker array. BKB-SIN sentences were presented from 0° azimuth, while multi-talker babble was presented from various loudspeakers. BKB-SIN scores in bilateral and the best unilateral listening conditions were compared to determine the amount of improvement gained.Results: As a group, the participants had improved speech understanding scores in the bilateral listening condition. Although not statistically significant, the auditory-verbal group tended to have greater speech understanding with greater levels of competing background noise, compared to the auditory-oral participants.Discussion: Bilateral cochlear implantation provides individuals with prelingual and childhood hearing loss with improved speech understanding in noise. A higher emphasis on auditory development during the critical language development years may add to increased speech understanding in adulthood. However, other demographic factors such as age or device characteristics must also be considered.Conclusion: Although both auditory-verbal and auditory-oral approaches emphasize spoken language development, they emphasize auditory development to different degrees. This may affect cochlear implant (CI) outcomes. Further consideration should be made in future auditory research to determine whether these differences contribute to performance outcomes. Additional investigation with a larger participant pool, controlled for effects of age and CI devices and processing strategies, would be necessary to determine whether language learning approaches are associated with different levels of speech understanding performance.

The effect of presentation level and stimulation rate on speech perception and modulation detection for cochlear implant users.

In order to improve speech understanding for cochlear implant users, it is important to maximize the transmission of temporal information. The combined effects of stimulation rate and presentation level on temporal information transfer and speech understanding remain unclear. The present study systematically varied presentation level (60, 50, and 40 dBA) and stimulation rate [500 and 2400 pulses per second per electrode (pps)] in order to observe how the effect of rate on speech understanding changes for different presentation levels. Speech recognition in quiet and noise, and acoustic amplitude modulation detection thresholds (AMDTs) were measured with acoustic stimuli presented to speech processors via direct audio input (DAI). With the 500 pps processor, results showed significantly better performance for consonant-vowel nucleus-consonant words in quiet, and a reduced effect of noise on sentence recognition. However, no rate or level effect was found for AMDTs, perhaps partly because of amplitude compression in the sound processor. AMDTs were found to be strongly correlated with the effect of noise on sentence perception at low levels. These results indicate that AMDTs, at least when measured with the CP910 Freedom speech processor via DAI, explain between-subject variance of speech understanding, but do not explain within-subject variance for different rates and levels.

Acoustic plus electric speech processing: Long-term results.

Few studies have investigated the stability of residual hearing and speech perception outcomes in individuals who were implanted with a shorter electrode device. Longitudinal, single-subject design. Fifty subjects who received a Nucleus Hybrid (Cochlear, Sydney, Australia) short electrode cochlear implant (CI) and had a minimum of 2 years (and up to 15 years) of postoperative longitudinal experience were included in this study. Twenty-three subjects received a Nucleus Hybrid S8 (S8); 14 subjects received a Nucleus Hybrid L24 (L24); and 13 received a Nucleus Hybrid S12 (S12). Audiometric thresholds and consonant-nucleus-consonant (CNC) words were collected pre- and postoperatively for up to 15 years for the S8 subjects and for up to 7 years for the S12 and L24 subjects. AzBio Sentences in multi-talker babble was collected for up to 7 years on the S12 and L24 subjects. Longitudinally, 83% of the S8 subjects, 92% of the S12 subjects, and 86% of the L24 subjects maintained a functional hearing pure-tone average (PTA) (125-500 Hz). Predicted change using a piecewise linear mixed model in PTA over time showed a postoperative linear decrease in hearing for each group until 0.5 years, after which the PTA stabilizes and is maintained. The averaged individual data for CNC and AzBio sentences show a significant improvement in scores by 0.25 to 0.5 years postimplantation, after which scores start to reach their maximum. This long-term study demonstrates that acoustic-electric processing hearing and improvement in speech understanding in quiet and in noise can be accomplished and sustained for many years with a short electrode CI. 2C. Laryngoscope, 128:473-481, 2018.

Computer-assisted CI fitting: Is the learning capacity of the intelligent agent FOX beneficial for speech understanding?

Objective: The software application FOX (‘Fitting to Outcome eXpert’) is an intelligent agent to assist in the programing of cochlear implant (CI) processors. The current version utilizes a mixture of deterministic and probabilistic logic which is able to improve over time through a learning effect. This study aimed at assessing whether this learning capacity yields measurable improvements in speech understanding.Methods: A retrospective study was performed on 25 consecutive CI recipients with a median CI use experience of 10 years who came for their annual CI follow-up fitting session. All subjects were assessed by means of speech audiometry with open set monosyllables at 40, 55, 70, and 85 dB SPL in quiet with their home MAP. Other psychoacoustic tests were executed depending on the audiologist's clinical judgment. The home MAP and the corresponding test results were entered into FOX. If FOX suggested to make MAP changes, they were implemented and another speech audiometry was performed with the new MAP.Results: FOX suggested MAP changes in 21 subjects (84%). The within-subject comparison showed a significant median improvement of 10, 3, 1, and 7% at 40, 55, 70, and 85 dB SPL, respectively. All but two subjects showed an instantaneous improvement in their mean speech audiometric score.Discussion: Persons with long-term CI use, who received a FOX-assisted CI fitting at least 6 months ago, display improved speech understanding after MAP modifications, as recommended by the current version of FOX. This can be explained only by intrinsic improvements in FOX's algorithms, as they have resulted from learning. This learning is an inherent feature of artificial intelligence and it may yield measurable benefit in speech understanding even in long-term CI recipients.

Evaluation of a wireless remote microphone in bimodal cochlear implant recipients

Objective: To evaluate the benefit of a wireless remote microphone (MM) for speech recognition in noise in bimodal adult cochlear implant (CI) users both in a test setting and in daily life. Design: This prospective study measured speech reception thresholds in noise in a repeated measures design with factors including bimodal hearing and MM use. The participants also had a 3-week trial period at home with the MM. Study sample: Thirteen post-lingually deafened adult bimodal CI users. Results: A significant improvement in SRT of 5.4 dB was found between the use of the CI with the MM and the use of the CI without the MM. By also pairing the MM to the hearing aid (HA) another improvement in SRT of 2.2 dB was found compared to the situation with the MM paired to the CI alone. In daily life, participants reported better speech perception for various challenging listening situations, when using the MM in the bimodal condition. Conclusion: There is a clear advantage of bimodal listening (CI and HA) compared to CI alone when applying advanced wireless remote microphone techniques to improve speech understanding in adult bimodal CI users.

A Sound Therapy-Based Intervention to Expand the Auditory Dynamic Range for Loudness among Persons with Sensorineural Hearing Losses: Case Evidence Showcasing Treatment Efficacy.

Case evidence is presented that highlights the clinical relevance and significance of a novel sound therapy-based treatment. This intervention has been shown to be efficacious in a randomized controlled trial for promoting expansion of the dynamic range for loudness and increased sound tolerance among persons with sensorineural hearing losses. Prior to treatment, these individuals were unable to use aided sound effectively because of their limited dynamic ranges. These promising treatment effects are shown in this article to be functionally significant, giving rise to improved speech understanding and enhanced hearing aid benefit and satisfaction, and, in turn, to enhanced quality of life posttreatment. These posttreatment sound therapy effects also are shown to be sustained, in whole or part, with aided environmental sound and to be dependent on specialized counseling to maximize treatment benefit. Importantly, the treatment appears to be efficacious for hearing-impaired persons with primary hyperacusis (i.e., abnormally reduced loudness discomfort levels [LDLs]) and for persons with loudness recruitment (i.e., LDLs within the typical range), which suggests the intervention should generalize across most individuals with reduced dynamic ranges owing to sensorineural hearing loss. An exception presented in this article is for a person describing the perceptual experience of pronounced loudness adaptation, which apparently rendered the sound therapy inaudible and ineffectual for this individual. Ultimately, these case examples showcase the enormous potential of a surprisingly simple sound therapy intervention, which has utility for virtually all audiologists to master and empower the adaptive plasticity of the auditory system to achieve remarkable treatment benefits for large numbers of individuals with sensorineural hearing losses.

Results of Speech Audiometry Testing in Case of Transcranial CROS Depend on Duration of Deafness

In single sided deafness, treatment with transcranial CROS makes pseudo stereophonic listening possible. This leads to improved speech understanding in noise. However, several reports show large variations between the individual results of the benefit by speech audiometry in noise. One possible factor is the duration and changes in the auditory pathway between the onset of deafness to CROS supply. 18 patients with single sided deafness have tested a transcranial CROS supply. The speech intelligibility thresholds were evaluated in 2 spatial hearing situations each with CROS and unaided. When speech was arriving at 45° from the deaf ear and noise at 45° from the hearing ear, a significant improvement of speech reception threshold for 50% intelligibility was detected by CROS supply compared the medians. Patients with longer duration of deafness showed higher benefit by an average of -4.0 dB, in contrast to patients with short duration of deafness. In the reversed situation, that speech on the hearing ear and noise on the deaf ear was a significant deterioration observed, an average of 3.1 dB at longer deafened patients. In addition, a highly significant correlation was found with the individual changes in the speech recognition threshold between the two situations. The duration of deafness is an essential factor in the individual benefit estimate for treatment with transcranial CROS supply. The time frame for audimetrically proven changes in the auditory pathway as a result of unilateral auditory deprivation can be estimated to about 1-3 years. Patients with short duration of deafness have low or no benefit from transcranial CROS supply.

For some bilateral cochlear implantees, a second implant can cause interference rather than improved speech understanding in the presence of competing speech

The goal of bilateral cochlear implantation is to provide binaural-processing benefits, such as improved sound localization and speech understanding in background noise. A recent study [Bernstein et al., Ear Hear. 37, 282-288] showed that bilateral cochlear-implant (BICI) listeners could receive up to 5 dB of binaural speech-understanding benefit when listening with two ears compared to one. However, one outlier demonstrated interference rather than improvement from the second ear, which warranted further investigation. We recruited nine BICI listeners with pre- or peri-lingual onset of deafness and/or a long duration of deafness in at least one ear. We hypothesized these listeners might also demonstrate interference in binaural speech understanding. They listened to a male target and a male interferer, both taken from the Coordinate Response Measure corpus, in monaural (target and interferer in one ear) and binaural (monaural target, diotic interferer) listening configurations. On average, listeners received 9 dB of interference from their second ear. For listeners with a much longer duration of deafness in one ear, interference patterns were asymmetrical (little interference in the first implanted ear, extreme interference in the second). These data demonstrate that certain spatial listening configurations may hinder the advantages of bilateral implants for some users.

Smartphone-based noise adaptive speech enhancement for hearing aid applications.

It is well established that the presence of environmental noises has a negative impact on the performance of hearing aid devices. This paper addresses a noise adaptive speech enhancement solution for the purpose of improving the performance of hearing aid devices in noisy environments. Depending on three noise types of babble, machinery, and driving car, the parameters of a recently developed speech enhancement algorithm are appropriately adjusted to gain improved speech understanding performance in noisy environments. This solution is implemented on smartphone platforms as an app and interfaced with a hearing aid device. A clinical testing protocol is devised to evaluate the performance of the app in participants with normal hearing and hearing impairments. The clinical testing results have indicated that statistically significant improvement in speech understanding is gained between the unprocessed and processed conditions using the developed noise adaptive speech enhancement solution.

Listening Effort in Younger and Older Adults: A Comparison of Auditory-Only and Auditory-Visual Presentations

One goal of the present study was to establish whether providing younger and older adults with visual speech information (both seeing and hearing a talker compared with listening alone) would reduce listening effort for understanding speech in noise. In addition, we used an individual differences approach to assess whether changes in listening effort were related to changes in visual enhancement-the improvement in speech understanding in going from an auditory-only (A-only) to an auditory-visual condition (AV) condition. To compare word recognition in A-only and AV modalities, younger and older adults identified words in both A-only and AV conditions in the presence of six-talker babble. Listening effort was assessed using a modified version of a serial recall task. Participants heard (A-only) or saw and heard (AV) a talker producing individual words without background noise. List presentation was stopped randomly and participants were then asked to repeat the last three words that were presented. Listening effort was assessed using recall performance in the two- and three-back positions. Younger, but not older, adults exhibited reduced listening effort as indexed by greater recall in the two- and three-back positions for the AV compared with the A-only presentations. For younger, but not older adults, changes in performance from the A-only to the AV condition were moderately correlated with visual enhancement. Results are discussed within a limited-resource model of both A-only and AV speech perception.

Benefit of contralateral routing of signals for unilateral cochlear implant users.

One way to improve speech understanding in noise for HI with a unilateral hearing loss is by contralateral routing of signals (CROS). Such a CROS-system captures sounds with an additional microphone at the worst hearing ear and transmits these to the better one. The better ear is then provided with a mix of signals originating from both ears. The goal of this study is to quantify the effect of a CROS-system on speech reception thresholds (SRTs) with unilaterally implanted CI-users in diffuse and directional noise as a function of speaker location. Listening tests are performed and an accurate directional intelligibly model is proposed used for further analysis. In diffuse noise it is concluded that the use of a CROS system results in a maximum gain in SRT of 7.9 dB when speech comes from the CROS side compared to a maximum loss in SRT of 2.1 dB when speech comes from the implanted side. In the case of directional noise, the effect of the CROS is symmetric and the maximum loss or gain in SRT was around 9 dB. The study therefore shows a clear potential of using the CROS system in diffuse noise.

Matching Automatic Gain Control Across Devices in Bimodal Cochlear Implant Users.

The purpose of this study was to improve bimodal benefit in listeners using a cochlear implant (CI) and a hearing aid (HA) in contralateral ears, by matching the time constants and the number of compression channels of the automatic gain control (AGC) of the HA to the CI. Equivalent AGC was hypothesized to support a balanced loudness for dynamically changing signals like speech and improve bimodal benefit for speech understanding in quiet and with noise presented from the side(s) at 90 degree. Fifteen subjects participated in the study, all using the same Advanced Bionics Harmony CI processor and HA (Phonak Naida S IX UP). In a 3-visit crossover design with 4 weeks between sessions, performance was measured using a HA with a standard AGC (syllabic multichannel compression with 1 ms attack time and 50 ms release time) or an AGC that was adjusted to match that of the CI processor (dual AGC broadband compression, 3 and 240 msec attack time, 80 and 1500 msec release time). In all devices, the AGC was activated above the threshold of 63 dB SPL. The authors balanced loudness across the devices for soft and loud input sounds in 3 frequency bands (0 to 548, 548 to 1000, and >1000 Hz). Speech understanding was tested in free field in quiet and in noise for three spatial speaker configurations, with target speech always presented from the front. Single-talker noise was either presented from the CI side or the HA side, or uncorrelated stationary speech-weighted noise or single-talker noise was presented from both sides. Questionnaires were administered to assess differences in perception between the two bimodal fittings. Significant bimodal benefit over the CI alone was only found for the AGC-matched HA for the speech tests with single-talker noise. Compared with the standard HA, matched AGC characteristics significantly improved speech understanding in single-talker noise by 1.9 dB when noise was presented from the HA side. AGC matching increased bimodal benefit insignificantly by 0.6 dB when noise was presented from the CI implanted side, or by 0.8 (single-talker noise) and 1.1 dB (stationary noise) in the more complex configurations with two simultaneous maskers from both sides. In questionnaires, subjects rated the AGC-matched HA higher than the standard HA for understanding of one person in quiet and in noise, and for the quality of sounds. Listening to a slightly raised voice, subjects indicated increased listening comfort with matched AGCs. At the end of the study, 9 of 15 subjects preferred to take home the AGC-matched HA, 1 preferred the standard HA and 5 subjects had no preference. For bimodal listening, the AGC-matched HA outperformed the standard HA in speech understanding in noise tasks using a single competing talker and it was favored in questionnaires and in a subjective preference test. When noise was presented from the HA side, AGC matching resulted in a 1.9 dB SNR additional benefit, even though the HA was at the least favorable SNR side in this speaker configuration. Our results possibly suggest better binaural processing for matched AGCs.

Method and application of auditory-visual attention training

The main idea underlying the proposed attention training is to perform stimulation of the hearing and sight senses employing digital signal processing algorithms controlled by electroencephalography signals. The auditory and visual stimuli are designated to force the perception through hearing and sight senses by the appropriate hemisphere. The applied speech modification uses a non-uniform real-time speech stretching algorithm. The video content retrieval showing the speaker's face is slowed down, accordingly. Research experiments employed subjects with central auditory and visual processing disorders revealing severe communication difficulties. The effectiveness of the proposed method has been shown using formal attention focus tests. It was demonstrated that the proposed method of attention training helps improve speech understanding and reading skills in examined subjects. [Research sponsored by the Polish National Science Centre, Dec. No. DEC-2014/15/B/ST7/04724.]

Efficacy and viability of an algorithm to improve speech understanding in noise for the hearing impaired

A primary complaint of hearing-impaired individuals involves poor speech understanding when background noise is present. Hearing aids and cochlear implants often allow good speech understanding in quiet backgrounds. However, the listeners’ noise intolerance and the devices’ inability to effectively combat background noise often conspire to produce poor performance in noise. Perhaps surprisingly, effective solutions to this problem have remained elusive despite considerable effort. One promising solution involves a single-microphone algorithm to extract speech from background noise. The algorithm is based on the concept of the ideal binary or ratio mask, and employs standard machine-learning techniques to train a deep neural network to estimate the mask, given only the speech-plus-noise mixture. Existing data indicate that large intelligibility increases by hearing-impaired listeners may be obtained across a variety of noisy conditions. In this talk, an overview of this approach will be provided, and the potential for implementation into hearing aids and cochlear implants will be discussed. [Work supported by NIH.]