Wireless communication between personal electronic devices and hearing aids using high frequency audio and ultrasound.

Hearing aids continue to be the main intervention for hearing loss but ease of use and control is of concern due to the small size of these aids. While technological advances in Bluetooth Low Energy have allowed for improved wireless control, in particular between personal electronic devices, its use for communication with hearing aids is problematic due to limited battery life. This paper outlines the implementation of acoustic wireless communication between personal electronic devices and hearing aids using On-Off Keying (OOK) and Frequency Shift Keying (FSK) between the frequencies of 16 and 20 kHz.

Investigating the Impact of Hearing Aid Use and Auditory Training on Cognition, Depressive Symptoms, and Social Interaction in Adults With Hearing Loss: Protocol for a Crossover Trial.

Background: Sensorineural hearing loss is the most common sensory deficit among older adults. Some of the psychosocial consequences of this condition include difficulty in understanding speech, depression, and social isolation. Studies have shown that older adults with hearing loss show some age-related cognitive decline.

Pitch matching in bimodal cochlear implant patients: Effects of frequency, spectral envelope, and level.

This study systematically investigated the effects of frequency, level, and spectral envelope on pitch matching in twelve bimodal cochlear implant (CI) users. The participants were asked to vary the frequency and level of a pure or complex tone (adjustable sounds) presented in the non-implanted ear to match the pitch and loudness of different reference stimuli presented to the implanted ear. Three reference sounds were used: single electrode pulse trains, pure tones, and piano notes.

Identification of Characters and Localization of Images Using Direct Multiple-Electrode Stimulation With a Suprachoroidal Retinal Prosthesis.

Purpose: Retinal prostheses provide vision to blind patients by eliciting phosphenes through electrical stimulation. This study explored whether character identification and image localization could be achieved through direct multiple-electrode stimulation with a suprachoroidal retinal prosthesis.

Methods: Two of three retinitis pigmentosa patients implanted with a suprachoroidal electrode array were tested on three psychophysical tasks.

Determining the Contribution of Retinotopic Discrimination to Localization Performance With a Suprachoroidal Retinal Prosthesis.

Purpose: With a retinal prosthesis connected to a head-mounted camera, subjects can perform low vision tasks using a combination of electrode discrimination and head-directed localization. The objective of the present study was to investigate the contribution of retinotopic electrode discrimination (perception corresponding to the arrangement of the implanted electrodes with respect to their position beneath the retina) to visual performance for three recipients of a 24-channel suprachoroidal retinal implant. Proficiency in retinotopic discrimination may allow good performance with smaller head movements, and identification of this ability would be useful for targeted rehabilitation.

An integrated model of pitch perception incorporating place and temporal pitch codes with application to cochlear implant research.

Although the neural mechanisms underlying pitch perception are not yet fully understood, there is general agreement that place and temporal representations of pitch are both used by the auditory system. This paper describes a neural network model of pitch perception that integrates both codes of pitch and explores the contributions of, and the interactions between, the two representations in simulated pitch ranking trials in normal and cochlear implant hearing. The model can replicate various psychophysical observations including the perception of the missing fundamental pitch and sensitivity to pitch interval sizes.

The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis.

Purpose: Phosphenes are the fundamental building blocks for presenting meaningful visual information to the visually impaired using a bionic eye device. The aim of this study was to characterize the size, shape, and location of phosphenes elicited using a suprachoroidal retinal prosthesis.

Methods: Three patients with profound vision loss due to retinitis pigmentosa were implanted with a suprachoroidal electrode array, which was used to deliver charge-balanced biphasic constant-current pulses at various rates, amplitudes, and durations to produce phosphenes.

Advances in implantable bionic devices for blindness: a review.

Since the 1950s, vision researchers have been working towards the ambitious goal of restoring a functional level of vision to the blind via electrical stimulation of the visual pathways. Groups based in Australia, USA, Germany, France and Japan report progress in the translation of retinal visual prosthetics from the experimental to clinical domains, with two retinal visual prostheses having recently received regulatory approval for clinical use. Regulatory approval for cortical visual prostheses is yet to be obtained; however, several groups report plans to conduct clinical trials in the near future, building upon the seminal clinical studies of Brindley and Dobelle.

Learning Pitch with STDP: A Computational Model of Place and Temporal Pitch Perception Using Spiking Neural Networks.

Pitch perception is important for understanding speech prosody, music perception, recognizing tones in tonal languages, and perceiving speech in noisy environments. The two principal pitch perception theories consider the place of maximum neural excitation along the auditory nerve and the temporal pattern of the auditory neurons' action potentials (spikes) as pitch cues. This paper describes a biophysical mechanism by which fine-structure temporal information can be extracted from the spikes generated at the auditory periphery.

Effectiveness of a teleaudiology approach to hearing aid fitting.

This research was conducted to evaluate the efficacy of an online speech perception test (SPT) for the measurement of hearing and hearing aid fitting in comparison with conventional methods. Phase 1 was performed with 88 people to evaluate the SPT for the detection of significant hearing loss. The SPT had high sensitivity (94%) and high selectivity (98%).

A Retrospective Multicenter Study Comparing Speech Perception Outcomes for Bilateral Implantation and Bimodal Rehabilitation.

Objectives: To compare speech perception outcomes between bilateral implantation (cochlear implants [CIs]) and bimodal rehabilitation (one CI on one side plus one hearing aid [HA] on the other side) and to explore the clinical factors that may cause asymmetric performances in speech intelligibility between the two ears in case of bilateral implantation.

Design: Retrospective data from 2247 patients implanted since 2003 in 15 international centers were collected. Intelligibility scores, measured in quiet and in noise, were converted into percentile ranks to remove differences between centers.

neuroBi: A Highly Configurable Neurostimulator for a Retinal Prosthesis and Other Applications.

To evaluate the efficacy of a suprachoroidal retinal prosthesis, a highly configurable external neurostimulator is required. In order to meet functional and safety specifications, it was necessary to develop a custom device. A system is presented which can deliver charge-balanced, constant-current biphasic pulses, with widely adjustable parameters, to arbitrary configurations of output electrodes.

First-in-human trial of a novel suprachoroidal retinal prosthesis.

Unlabelled: Retinal visual prostheses ("bionic eyes") have the potential to restore vision to blind or profoundly vision-impaired patients. The medical bionic technology used to design, manufacture and implant such prostheses is still in its relative infancy, with various technologies and surgical approaches being evaluated. We hypothesised that a suprachoroidal implant location (between the sclera and choroid of the eye) would provide significant surgical and safety benefits for patients, allowing them to maintain preoperative residual vision as well as gaining prosthetic vision input from the device.

Factors affecting perceptual thresholds in a suprachoroidal retinal prosthesis.

Purpose: The suprachoroidal location for a retinal prosthesis provides advantages over other locations in terms of a simplified surgical procedure and a potentially more stable electrode-neural interface. The aim of this study was to assess the factors affecting perceptual thresholds, and to optimize stimulus parameters to achieve the lowest thresholds in patients implanted with a suprachoroidal retinal prosthesis.

Methods: Three patients with profound vision loss from retinitis pigmentosa were implanted with a suprachoroidal array.

Application of a pitch perception model to investigate the effect of stimulation field spread on the pitch ranking abilities of cochlear implant recipients.

Although many cochlear implant (CI) recipients perceive speech very well in favorable conditions, they still have difficulty with music, speech in noisy environments, and tonal languages. Studies show that CI users' performance in these tasks are correlated with their ability to perceive pitch. The spread of stimulation field from the electrodes to the auditory nerve is one of the factors affecting performance.

Behavioral frequency discrimination ability of partially deafened cats using cochlear implants.

The aim of this study was to determine the effects of cochlear implant (CI) use on behavioral frequency discrimination ability in partially deafened cats. We hypothesized that the additional information provided by the CI would allow subjects to perform better on a frequency discrimination task. Four cats with a high frequency hearing loss induced by ototoxic drugs were first trained on a go/no-go, positive reinforcement, frequency discrimination task and reached asymptotic performance (measured by d' - detection theory).

An automated psychoacoustic testing apparatus for use in cats.

Animal behavioral studies make a significant contribution to hearing research and provide vital information which is not available from human subjects. Animal psychoacoustics is usually extremely time consuming and labor intensive; in addition, animals may become stressed, especially if restraints or negative reinforcers such as electric shocks are used. We present a novel behavioral experimental system that was developed to allow efficient animal training in response to acoustic stimuli.

Tone, rhythm, and timbre perception in school-age children using cochlear implants and hearing aids.

Background: Children with hearing impairments, especially those using hearing devices such as the cochlear implant (CI) or hearing aid (HA), are sometimes not encouraged to attend music classes, as they or their parents and teachers may be unsure whether the child can perform basic musical tasks.

Purpose: The objective of the current study was to provide a baseline for the performance of children using CIs and HAs on standardized tests of rhythm and pitch perception as well as an instrument timbre identification task. An additional aim was to determine the effect of structured music training on these measures during the course of a school year.

The acoustic and perceptual cues affecting melody segregation for listeners with a cochlear implant.

Our ability to listen selectively to single sound sources in complex auditory environments is termed "auditory stream segregation."This ability is affected by peripheral disorders such as hearing loss, as well as plasticity in central processing such as occurs with musical training. Brain plasticity induced by musical training can enhance the ability to segregate sound, leading to improvements in a variety of auditory abilities.

Visual prostheses for the blind.

After more than 40 years of research, visual prostheses are moving from the laboratory into the clinic. These devices are designed to provide prosthetic vision to the blind by stimulating localized neural populations in one of the retinotopically organized structures of the visual pathway - typically the retina or visual cortex. The long gestation of this research reflects the many significant technical challenges encountered including surgical access, mechanical stability, hardware miniaturization, hermetic encapsulation, high-density electrode arrays, and signal processing.

A cochlear implant user with exceptional musical hearing ability.

Unlabelled: Although the perception of music is generally poor in cochlear implant users, there are a few excellent performers.

Objective: The aim of this study was the assessment of different aspects of music perception in one exceptional cochlear implant user.

Design: The assessments included pitch direction discrimination, melody and timbre recognition, relative and absolute pitch judgment, and consonance rating of musical notes presented through the sound processor(s).

Pre-, per- and postoperative factors affecting performance of postlinguistically deaf adults using cochlear implants: a new conceptual model over time.

Objective: To test the influence of multiple factors on cochlear implant (CI) speech performance in quiet and in noise for postlinguistically deaf adults, and to design a model of predicted auditory performance with a CI as a function of the significant factors.

Study Design: Retrospective multi-centre study.

Methods: Data from 2251 patients implanted since 2003 in 15 international centres were collected.

Factors affecting auditory performance of postlinguistically deaf adults using cochlear implants: an update with 2251 patients.

Objective: To update a 15-year-old study of 800 postlinguistically deaf adult patients showing how duration of severe to profound hearing loss, age at cochlear implantation (CI), age at onset of severe to profound hearing loss, etiology and CI experience affected CI outcome.

Study Design: Retrospective multicenter study.

Methods: Data from 2251 adult patients implanted since 2003 in 15 international centers were collected and speech scores in quiet were converted to percentile ranks to remove differences between centers.

The effect of visual cues on difficulty ratings for segregation of musical streams in listeners with impaired hearing.

Background: Enjoyment of music is an important part of life that may be degraded for people with hearing impairments, especially those using cochlear implants. The ability to follow separate lines of melody is an important factor in music appreciation. This ability relies on effective auditory streaming, which is much reduced in people with hearing impairment, contributing to difficulties in music appreciation.

Factors contributing to speech perception scores in long-term pediatric cochlear implant users.

Objectives: The objectives of this report are to (1) describe the speech perception abilities of long-term pediatric cochlear implant (CI) recipients by comparing scores obtained at elementary school (CI-E, 8 to 9 yrs) with scores obtained at high school (CI-HS, 15 to 18 yrs); (2) evaluate speech perception abilities in demanding listening conditions (i.e., noise and lower intensity levels) at adolescence; and (3) examine the relation of speech perception scores to speech and language development over this longitudinal timeframe.