Auditory neuropathy in mice and humans with Friedreich ataxia.

Objective: Recent studies have found that human Friedreich ataxia patients have dysfunction of transmission in the auditory neural pathways. Here, we characterize hearing deficits in a mouse model of Friedreich ataxia and compare these to a clinical population.

Methods: Sixteen mice with a C57BL/6 background were evaluated.

Hearing Aid Use in Older Adults With Postlingual Sensorineural Hearing Loss: Protocol for a Prospective Cohort Study.

Background: Older adults with postlingual sensorineural hearing loss (SNHL) exhibit a poor prognosis that not only includes impaired auditory function but also rapid cognitive decline, especially speech-related cognition, in addition to psychosocial dysfunction and an increased risk of dementia. Consistent with this prognosis, individuals with SNHL exhibit global atrophic brain alteration as well as altered neural function and regional brain organization within the cortical substrates that underlie auditory and speech processing. Recent evidence suggests that the use of hearing aids might ameliorate this prognosis.

Cannula-based drug delivery to the guinea pig round window causes a lasting hearing loss that may be temporarily mitigated by BDNF.

Sustained local delivery of drugs to the inner ear may be required for future regenerative and protective strategies. The round window is surgically accessible and a promising delivery route. To be viable, a delivery system should not cause hearing loss.

Electrophysiological Evidence of the Basilar-Membrane Travelling Wave and Frequency Place Coding of Sound in Cochlear Implant Recipients.

Aim: To obtain direct evidence for the cochlear travelling wave in humans by performing electrocochleography from within the cochlea in subjects implanted with an auditory prosthesis.

Background: Sound induces a travelling wave that propagates along the basilar membrane, exhibiting cochleotopic tuning with a frequency-dependent phase delay. To date, evoked potentials and psychophysical experiments have supported the presence of the travelling wave in humans, but direct measurements have not been made.

Applying Neurotrophins to the Round Window Rescues Auditory Function and Reduces Inner Hair Cell Synaptopathy After Noise-induced Hearing Loss.

Hypothesis: Applying neurotrophins to the round window immediately after a single noise exposure will prevent noise-induced hidden hearing loss.

Background: Loud noise can eliminate neural connections between inner hair cells and their afferent neurons (thereby diminishing sound perception) without causing a detectable change on audiogram. This phenomenon is termed hidden hearing loss.

Correlates of smoking among youth: the role of parents, friends, attitudes/beliefs, and demographics.

Background: Family engagement has been shown to play a crucial role in youth cigarette use prevention and uptake. We examine cross-sectional and longitudinal data to determine whether changes in parental monitoring factors influence changes in smoking susceptibility.

Methods: Two cross-sectional surveys of Florida youth (12-17 years) were conducted in 2009, with a follow-up survey in 2010.

Intraoperative Real-time Cochlear Response Telemetry Predicts Hearing Preservation in Cochlear Implantation.

Aim: To monitor cochlear function during cochlear implantation and determine correlations with postoperative acoustic hearing.

Background: Cochlear response telemetry measures cochlear function directly from cochlear implant electrodes. We have adapted this system to provide real-time cochlear response telemetry (RT-CRT) monitoring of a patient's acoustic hearing as the cochlear implant electrode array is inserted.

A microelectromechanical system artificial basilar membrane based on a piezoelectric cantilever array and its characterization using an animal model.

We proposed a piezoelectric artificial basilar membrane (ABM) composed of a microelectromechanical system cantilever array. The ABM mimics the tonotopy of the cochlea: frequency selectivity and mechanoelectric transduction. The fabricated ABM exhibits a clear tonotopy in an audible frequency range (2.

Identifying misclassification in youth self-reported smoking status: testing different consent processes of biological sample collection to capture misclassification.

Introduction: In Florida, since 1998, identical survey items have been used to measure youth smoking status for the CDC sponsored state school-based survey and the tobacco control program evaluation telephone survey. The two surveys should parallel one another to track tobacco use. Tobacco items collected in the two surveys closely paralleled one another until recently.

Training of cochlear implant users to improve pitch perception in the presence of competing place cues.

Objectives: Perception of musical pitch in cochlear implant (CI) systems is relatively poor compared with normal hearing and can be adversely affected by changes in spectral timbre coded by stimulation place. In this study, we evaluated whether the perception of musical pitch could be improved through specific training designed to teach listeners to attend to fundamental frequency (F0) exclusively for judgment of pitch and to spectral envelope exclusively for discrimination of spectral timbre.

Design: A computer-based training program to improve musical pitch perception was developed that required listeners to match acoustic patterns of pitch and spectral timbre to visual patterns.

Young adult former ever smokers: the role of type of smoker, quit attempts, quit aids, attitudes/beliefs, and demographics.

Objective: Young adults who smoke are often nondaily users who either quit or transition into dependent smokers. Further, this age group often has been considered an extension of the adult population. This study aims to examine young adult former ever smokers to understand factors associated with their stopping smoking.

Pitch and loudness matching of unmodulated and modulated stimuli in cochlear implantees.

The pitch elicited by unmodulated and amplitude modulated electrical pulse trains was examined with six adult cochlear implantees. In addition, for three of those subjects who had some hearing in their contralateral ear, the pitch of unmodulated electrical pulse trains was compared to that of complex harmonic acoustic tones. In the first experiment, pulse rate discrimination and the effects of place and level differences on pitch were examined for unmodulated pulse trains.

Correlates of smoking among young adults: the role of lifestyle, attitudes/beliefs, demographics, and exposure to anti-tobacco media messaging.

Background: Young adults (18-24 years) have the highest smoking rate of any age group. Unlike youth/adult populations where there is one primary message targeting behavior, anti-tobacco campaigns targeting young adults should contain messages of prevention and cessation. The objective was to identify factors influencing young adult cigarette use, employing the Centers for Disease Control and Prevention logic model, with an emphasis on the role of lifestyle, tobacco use tolerance, and attitudes/beliefs.

Prediction and control of neural responses to pulsatile electrical stimulation.

This paper aims to predict and control the probability of firing of a neuron in response to pulsatile electrical stimulation of the type delivered by neural prostheses such as the cochlear implant, bionic eye or in deep brain stimulation. Using the cochlear implant as a model, we developed an efficient computational model that predicts the responses of auditory nerve fibers to electrical stimulation and evaluated the model's accuracy by comparing the model output with pooled responses from a group of guinea pig auditory nerve fibers. It was found that the model accurately predicted the changes in neural firing probability over time to constant and variable amplitude electrical pulse trains, including speech-derived signals, delivered at rates up to 889 pulses s(-1).

Brain-derived neurotrophic factor modulates auditory function in the hearing cochlea.

Neurotrophins prevent spiral ganglion neuron (SGN) degeneration in animal models of ototoxin-induced deafness and may be used in the future to improve the hearing of cochlear implant patients. It is increasingly common for patients with residual hearing to undergo cochlear implantation. However, the effect of neurotrophin treatment on acoustic hearing is not known.

Examining the auditory nerve fiber response to high rate cochlear implant stimulation: chronic sensorineural hearing loss and facilitation.

Neural prostheses, such as cochlear and retinal implants, induce perceptual responses by electrically stimulating sensory nerves. These devices restore sensory system function by using patterned electrical stimuli to evoke neural responses. An understanding of their function requires knowledge of the nerves responses to relevant electrical stimuli as well as the likely effects of pathology on nerve function.

Changes in youth cigarette use following the dismantling of an antitobacco media campaign in Florida.

We examined the association of the termination of a successful youth-targeted antitobacco media campaign ("truth") and changes in smoking rates among youths aged 12-17 years in Florida. Six telephone-based surveys were completed during the active media campaign (1998-2001), and 2 postcampaign surveys were completed in 2004 and 2006 (each n approximately 1,800). Prevalence of current smoking among youth observed during the campaign continued to decrease in the first postcampaign survey; however, by the second follow-up survey, youth smoking rates had increased significantly for youth aged 16 years or older.

Round window delivery of dexamethasone ameliorates local and remote hearing loss produced by cochlear implantation into the second turn of the guinea pig cochlea.

Application of dexamethasone to the round window has been shown to ameliorate high frequency hearing loss resulting from the trauma of cochlear implantation in experimental animals, but elucidation of the factors influencing protection of the high frequencies has been confounded by the local trauma from electrode array insertion. In this experiment, a second turn cochleostomy and implantation was performed on guinea pigs, to examine protection in the basal turn without the confounding effect of local trauma, as well as to test the efficacy of hearing protection in the second cochlear turn. The implantation resulted in an increase in hearing thresholds across all frequencies examined (2-32 kHz).

Targeted therapy of the inner ear.

Background: There is experimental evidence that targeted delivery of steroids to the inner ear can protect hearing during cochlear implant surgery. The best protection appears to be achieved through pre-treatment of the cochlea, but the time period required for treatment is long compared with the duration of surgery, and needs further optimization. The stability of hearing thresholds is determined over a 3-month period after hearing preservation cochlear implantation.

Factors influencing the efficacy of round window dexamethasone protection of residual hearing post-cochlear implant surgery.

Aim: To protect hearing in an experimental model of cochlear implantation by the application of dexamethasone to the round window prior to surgery. The present study examined the dosage and timing relationships required to optimise the hearing protection.

Methods: Dexamethasone or saline (control) was absorbed into a pledget of the carboxymethylcellulose and hyaluronic acid and applied to the round window of the guinea pig prior to cochlear implantation.

Deafness alters auditory nerve fibre responses to cochlear implant stimulation.

Here we characterized the relationship between duration of sensorineural hearing loss and the response of the auditory nerve to electrical stimulus rate. Electrophysiological recordings were made from undeafened guinea pigs and those ototoxically deafened for either 5 weeks or 6 months. Auditory neuron survival decreased significantly with the duration of deafness.

Using classification trees to profile adolescent smoking behaviors.

The purpose of this study was to explore the interactive nature of various predictor variables in profiling adolescent smoking behaviors characterized by intention to smoke, current, situational, and established smoking using classification trees. The data (n = 3610) were obtained from cross-sectional telephone surveys of the Florida Anti-Tobacco Media Evaluation Program. Three classification trees were constructed, namely, intention versus no intention to smoke among non-smokers, current smokers versus non-smokers, and established versus situational smokers.

The outcome consequences of defunding the Minnesota youth tobacco-use prevention program.

Objective: To assess the immediate and intermediate outcome consequences of defunding a successful tobacco use prevention program.

Methods: A four-survey repeated cross-sectional design is employed. Two surveys were completed while the program was fully operational, one after program dismantling was initiated and another about 6 months after the campaign was completely dismantled.

Assessing the reliability and validity of anti-tobacco attitudes/beliefs in the context of a campaign strategy.

Objectives: To identify multi-item attitude/belief scales associated with the theoretical foundations of an anti-tobacco counter-marketing campaign and assess their reliability and validity.

Methods: The data analyzed are from two state-wide, random, cross-sectional telephone surveys [n(S1)=1,079, n(S2)=1,150]. Items forming attitude/belief scales are identified using factor analysis.