Communication Sciences and Disorders Commons^™

Functional Recovery: A Mixed Methods Study Of The Specific Variables Within A Post-Hospital Inter-Disciplinary Brain Injury Rehabilitation - Residential Program, Victoria Harding

Dissertations, 2014-2019

The mixed methods explanatory design study examined specific constructs of Post Hospital Interdisciplinary Brain Injury Rehabilitation – Residential (PHIDBIR-R) programs that positively influenced gains in function. The investigation involved exploring the phenomenon of individuals’ experiences while participating in a PHIDBIR-R program as part of recovery from brain injury. The study’ primary purpose was to understand individuals who make the greatest gains in function while participating in these programs, as measured by the Mayo-Portland Adaptability Inventory-4 (MPAI-4) change scores from admission to discharge and what are the components of these programs that may contribute to individuals’ gains in function.

Data were …

The Effect Of Taste On Swallowing Function, Rachel Mulheren

Dissertations, 2014-2019

This study investigated the effects of taste on swallowing frequency and cortical activation in the swallowing network. The effects of salivary flow and taster status were also examined, along with genetic taster status. The effects of a 3ml bolus compared sour, sour with slow infusion, sweet, water, and water with infusion. Swallowing frequency was significantly higher 0-15 seconds after bolus delivery than 16-30 seconds. Swallowing frequency was higher in the sour conditions, whereas sweet and water did not differ. Functional near-infrared spectroscopy recordings measured changes in blood oxygenation (HbO) in the right and left hemispheres in the premotor, S1 and …

The Effect Of Auditory Fatigue On Reaction Time In Normal Hearing Listeners, Beth I. Hulvey

Dissertations, 2014-2019

Hearing impaired individuals often report feeling fatigue at the end of the day. These individuals are forced to exert more cognitive effort throughout the day as they strain to understand speech in an ever-changing auditory environment through an impaired/degraded auditory system (Rabbitt, 1991). Today’s digital hearing aids attempt to increase audibility and relieve cognitive strain through advanced signal processing techniques such as digital noise reduction (DNR). Recent research regarding noise and its effects on auditory fatigue in hearing impaired listeners suggests that DNR may reduce the effects of auditory fatigue (Sarampalis et al, 2009). The overarching goal of a future …

Pre-Pulse Inhibition Assessment Of Sound Localization In Mice: Methodological, Functional, And Genetic Considerations, Megan Klingenberg

Dissertations, 2014-2019

Sound localization is an important aspect of normal hearing. The Eph/ephin family of signaling proteins, studied here, is known to guide the formation of central auditory connections in early development, particularly topographic inputs from the lateral superior olive (LSO) to the inferior colliculus (IC). Processing in the LSO and its influences on the IC are known to be heavily involved in sound localization tasks. One way to study sound localization in mice is through pre-pulse inhibition (PPI). PPI is the phenomenon by which a weak prestimulus inhibits the response to a subsequent startle stimulus. In studying sound localization, the prestimulus …

Examining Monaural And Binaural Measures Of Phase-Locking As A Function Of Age, Larissa M. Heckler

Dissertations, 2014-2019

Understanding speech in the presence of background noise is a common complaint of middle-aged and older listeners with clinically normal audiograms. There is great interest in understanding how age-related changes in auditory physiology make it harder for older adults to understand speech in difficult listening situations, compared to young listeners. It was recently reported that middle-aged and older normal-hearing listeners showed frequency-dependent, age-related declines in the behavioral and physiological detection of interaural phase differences (Grose & Mamo, 2010; Ross et al, 2007). There is also evidence of an age-related, frequency-dependent decline in the frequency-following response (FFR) (Clinard et al., 2010), …

Training To Avoid Distractions, Cara E. Sanderson

Dissertations, 2014-2019

Introduction: Auditory training has been extensively studied and applied to training software that is currently available for children with attention, hearing, or speech/language difficulties. The extent to which training generalizes, or transfers to an untrained task, is of great theoretical value. To our knowledge, there has not been a study that examines transference to a non-sensory masking task.

Methods: 16 adults without ADHD were trained in a contralateral masking task over the course of two days, with 900 trials per day. False alarm rates, thresholds, and reaction times were measured. Pre- and post-tests of contralateral and informational masking were conducted …

Effect Of Adaptive Frequency Lowering On Phoneme Identification And Sound Quality Of Music In Hearing-Impaired Listeners, Kaitlyn A. Sabri

Dissertations, 2014-2019

The most common type and configuration of hearing loss seen in clinics is high frequency sensorineural hearing loss. High-frequency hearing losses can lead to difficulties understanding speech in noise. Traditional amplification can aid in audibility of high-frequency information; however, its success is limited due to acoustic feedback, output limitations of the hearing aids, and loudness discomfort (Bohnert, Nyffeler, & Keilmann, 2010, Turner & Cummings, 1999). Cochlear dead regions further hinder the success of traditional hearing aids, as speech recognition may not improve with increased audibility (Turner & Cummings, 1999). Frequency-lowering algorithms, developed by four major hearing aid manufacturers, attempt to …

Effects Of Eph/Ephrin Mutations On Pre Pulse Inhibition In Mice, Andrea Marie Liuzzo

Dissertations, 2014-2019

The acoustic startle response (ASR) is a reliable reflexive behavioral response in mammals elicited by an unexpected intense acoustic startle eliciting stimulus (SES). It is mediated by a sub-cortical pathway that includes the inferior colliculus (IC). The ASR amplitude can be measured with an accelerometer beneath the subject attached to the cage, and can be decreased in amplitude by presenting a less intense, non-startling stimulus 20-300 ms before the SES. This reflexive decrement in ASR is called pre pulse inhibition (PPI) and indicates that the relatively soft pre pulse was heard. Murine species have been used to study this response …

Effects Of Auditory And Visual Distracters On Acceptable Background Noise Level In Hearing-Impaired Listeners, Elizabeth A. Ripley

Dissertations, 2014-2019

Acceptable Noise Level (ANL), is an established procedure for determining the amount of background noise a listener is willing to accept while listening to speech. ANL is established by having the listener select most amount of background noise they are willing to accept while listening to a speech stimulus presented at their most comfortable listening level (MCL). While ANLs have been established as good predictors of hearing aid use, little is known on how hearing aid users accept background noise while engaged in cognitively demanding tasks. Previous research in normal hearing listeners has demonstrated that listeners will allow the most …

The Neural Representation And Behavioral Detection Of Frequency Modulation, Daniel Elliott Shearer

Dissertations, 2014-2019

Understanding a speech signal is reliant on the ability of the auditory system to accurately encode rapidly changing spectral and temporal cues over time. Evidence from behavioral studies in humans suggests that relatively poor temporal fine structure (TFS) encoding ability is correlated with poorer performance on speech understanding tasks in quiet and in noise. Electroencephalography, including measurement of the frequency-following response, has been used to assess the human central auditory nervous system’s ability to encode temporal patterns in steady-state and dynamic tonal stimuli and short syllables. To date, the FFR has been used to investigate the accuracy of phase-locked auditory …

The Effects Of Various Modes Of Feedback On Preferred Ipod Listening Levels, Justine A. Mcdermott

Dissertations, 2014-2019

The current study was conducted in an effort to promote safe listening habits of personal media player device users. Devices such as the iPod are known to have high output capacities well within the range of potentially hazardous sound levels, thus there is a concern that personal listening may pose a risk to hearing. Intuitive and real-time feedback representing the risk of hearing damage based on selected Preferred Listening Levels (PLLs) was provided to subjects they listened to an iPod. Objective: To provide listeners with tools to judge ‘what is too loud’ (and potentially damaging to hearing) so that they …

The Effect Of Early Hearing Loss On Bobwhites’ Responses To Pure Tones: A Possible Animal Model Of Prelingual Deafness, Bethany Leanne Magee

Dissertations, 2014-2019

This study aimed to look at the behavioral responses of Bobwhite quail to pure tone stimuli by measuring peep suppression. We also considered if a duration of early hearing loss would affect Bobwhite’s responsiveness to the tones. Bobwhites were tested individually at all different ages post hatch day. The pure tones were presented at several different intensity levels and peep suppression was calculated as a measure of responsiveness to the stimuli. Mock trials were conducted as a measure of control to determine the birds’ typical peep rate. Some of the Bobwhite quail were injected with gentamicin 0-1 post-hatch day in …

The Acute Effects Of Gentamycin Ototoxicity On Bobwhite Quail Basilar Papilla And Auditory Brainstem Responses, Kristie Wilson

Dissertations, 2014-2019

The present study aimed to investigate the effectiveness of a single dose of gentamycin in elevating Auditory Brainstem Response (ABR) thresholds and causing inner ear hair cell loss or damage. A total of twenty-two Bobwhite quail were used (n=7 control, n=15 experimental); experimental group quail were injected with a 200 mg/kg dose of gentamycin within 24 hours of hatch (P0). Three to four days post-hatch or injection the quail underwent ABR testing. Thresholds were measured using a 1,000 Hz, 2,000 Hz, and 4,000 Hz tone pip and a click beginning at 90 dB nominalSPL. Resulting waveforms were analyzed using MATLAB …

Ultrasonic Vocalizations In Eph/Ephrin Mutant Mice, Bryna Rickenbach-Cline

Dissertations, 2014-2019

Purpose: Murine mammals, more commonly known as mice, emit ultrasonic vocalizations or “yelps” to communicate. It has been found that adult mice use these vocalizations to communicate with each other, and infant mice utilize ultrasonic vocalizations to communicate with their mother. It is known that a relationship exists between hearing ability and vocalization (Bass-Ringdahl, 2010). This study aims to record yelps/ vocalizations of four strains of mouse pups to determine how the development of hearing relates to the vocalizations that are emitted. It is thought that mice with compromised genes that encode for signaling proteins that are essential to the …

The Effects Of Musical Training On Perception And Neural Representation Of Temporal Fine Structure, Verleyne Andrews-Rodgers

Dissertations, 2014-2019

One of the most common complaints of persons with sensorineural hearing loss is difficulty hearing in background noise. Temporal fine structure (TFS) is one of the factors that contributes to understanding speech in the presence of background noise. TFS refers to the periodic information in speech which helps us to identify which speech sound we are listening to. TFS is also negatively affected by hearing loss, as well as age. In a quest to discover how TFS processing and thus speech-in-noise understanding can be improved, this study examined the effects of musical training on behavioral and physiological measures of temporal …

Quantifying Head Acceleration During Vestibular Rehabilitation, Anne Hogan

Dissertations, 2014-2019

Dizziness can often be a serious and confounding condition that ranges in severity from annoying to debilitating and affects many people. The most common and effective treatment for persistent dizziness is vestibular rehabilitation therapy, which falls into three categories: adaptation, sensory substitution, and habituation. While more is known about adaptation and sensory substitution, questions remain regarding the exact mechanisms of recovery for habituation. Precisely, the optimal stimulation to the vestibular system, as measured in intensity of head accelerations, is unknown for habituation treatment. In this dissertation are drafts of two manuscripts. The first explores the average intensity of linear and …

The Effects Of Auditory And Visual Distracters On The Toleration Of Background Noise In Normal Hearing Listeners, Lauren Shastany

Dissertations, 2014-2019

The primary objective of this study was to evaluate the effect of auditory and visual cognitive loads on the preferred background noise levels in normal-hearing listeners. This study investigated the preferable background noise levels (primary task) when normal hearing listeners were presented with auditory and/or visual cognitive distractions (secondary task). It was hypothesized that normal hearing listeners’ preferable background noise level would decrease in the presence of either distracter and that the synergistic effect of the two distracters would result in even lower preferable background noise level. Preferable background noise levels were measured on 24 normal-hearing listeners under four conditions. …

Perceived Occlusion And Comfort In Receiver-In-The-Ear Hearing Aids, Sara A. Conrad

Dissertations, 2014-2019

Purpose: In this study participants rated self-perceived occlusion and physical comfort for receiver-in-the-ear (RITE) hearing aids with different sizes of standard domes. Perceived occlusion was rated across listening and own voice conditions. Method: Twenty-one older adults with hearing impairment were fitted with bilateral RITE hearing aids and tested with three dome size conditions: open, plus, and power domes, and one control condition: the participants' own aids. Participants ranked self-perceived occlusion across the dome size conditions as well as across listening and own voice conditions, and also ranked level of physical comfort across dome sizes. Results: Self-perceived occlusion increased as dome …

Headturn Preference Of 10-Month Infants For Familiar And Unfamiliar Signs, Steven Thomas Kulsar

Dissertations, 2014-2019

Most deaf babies born in the United States are born into hearing families and show a developmental lag in spoken language acquisition, reading, writing, and social development when compared to deaf babies of deaf parents or hearing babies of hearing parents, due to limited language access. A modified headturn paradigm has been devised to assess infant preference to various familiar and unfamiliar ASL stimuli, to determine parallels between auditory-spoken and visual-spatial languages. If visual perception of first signs parallels auditory perception of first words, we would expect infants exposed to ASL as their native language to show a preference for …

A Comparison Of Vibrotactile And Air Puff Stimulation For Inducing Swallowing, Kathryn Diane White

Dissertations, 2014-2019

The purpose of this study was to evaluate the effectiveness of two types of non-invasive, sensory stimulation on increasing the rate of swallowing and for inducing cortical activity associated with swallowing. The types of stimulation investigated were vibrotactile stimulation to the external throat area surrounding the laryngeal tissues and oral air puff stimulation to the anterior faucial pillars. A functional near infrared spectroscopy (fNIRS) system measured relative changes in the concentration of oxygenated hemoglobin (HbO) in cortical sensorimotor regions as an indirect measure of brain activity. The experiment included 16 healthy adult participants between the ages of 28 and 60 …

The Effects Of Age On The Mismatch Negativity Response To Differences In Place Of Articulation, Meredith Robotti

Dissertations, 2014-2019

The Mismatch negativity (MMN) response measures the auditory system’s response to change in stimulus. This measurement can be used to identify if the auditory system can physiologically discriminate two speech sounds. To date, studies that have recorded MMNs in response to differing place of articulation show conflicting data. One possibility for the conflicting results is due to the lack of carefully controlled stimuli. The purpose of this study was to evaluate the differences in amplitude and latency between adult and infant MMN responses when manipulating place of articulation for speech. Additionally, this study sought to determine if all adults showed …

Normal And Mutant Murine Auditory Brainstem Responses (Abrs), Kristin Shearer

Dissertations, 2014-2019

Spatial organization and topographic maps begin in the periphery and are preserved throughout the central auditory system. The Eph and ephrin family of signaling proteins is involved in the patterning and arrangement of auditory afferents which code information about frequency, intensity, and time. The present study utilizes the ABR as a physiological measure of the electrical potentials occurring in the brainstem following acoustic stimulation. We recorded this measure following click and tone pip stimulation in ephrin-B3 and EphA4 deficient mice at 2-3 months of age and compared them to wild type controls. Significant findings included elevated auditory thresholds, prolonged latency …

Do Different Methods Of Hearing Aid Information Delivery Influence Knowledge Acquisition?, Lindsey Ann Parr

Dissertations, 2014-2019

The main purposes of this study were to examine whether or not there was a difference in knowledge acquisition as a function of training method (these included: face-to-face session, DVD, and pamphlet); to determine which information included in hearing aid orientation was commonly known prior to training and which showed the most learning after training; and to evaluate which training method is the most popular among participants. A sample of 65 young college students with no prior hearing aid experience completed a pre- and post-multiple-choice test of hearing aid knowledge and gave their opinion of the hearing aid orientation immediately …

An Exploration Of Swallowing Stimulation In The Infant, Sarah Elizabeth Hegyi

Dissertations, 2014-2019

The purpose of this study was twofold: to determine the effects of two types of non-invasive, peripheral sensory stimulation on the frequency of infant swallowing and to explore the cortical activation patterns in response to stimulation in the somatosensory and motor regions of the brain during infancy, between 2-4 months and 7-9 months of age. The two different forms of mechanical stimulation investigated include pacifier stimulation to the lips and oral cavity and vibrotactile stimulation via the external throat area to the laryngeal tissues. The study represents a prospective, repeated experimental research design. Investigators utilized an accelerometer and an inductive …

Objective And Subjective Evaluation Of Wind Noise Reduction In Digital Hearing Aids, Sheena Kate Jessee

Dissertations, 2014-2019

Wind noise is problematic for hearing aid users who enjoy outdoor activities. Not only is it annoying, it can create distortion by overloading the microphone and masking signals that hearing aid users desire to hear. Some hearing aid manufacturers offer wind noise reduction in addition to general noise reduction (WNR + NR) for clinicians to manipulate in their software. This study compares objective and subjective measures of wind noise reduction as well as subjective measure of intelligibility obtained using various hearing aid manufacturers and noise reduction settings while HINT sentences were played in the presence of constantly generated wind. Significant …

Effect Of Real-Ear Verification On Hearing Aid Benefit, Sarah K. Sporck

Dissertations, 2014-2019

Real-ear measurements have been proven to be the most accurate measure of hearing aid verification. However, many audiologists find real-ear to be too time consuming to use consistently. One popular reason for underutilizing real-ear verification is the use of first fitting algorithms provided on manufacturer programming software. However, the predicted fittings provided on the software are not an accurate means of providing what is recommended by popular prescriptive formulas (Hawkins and Cook, 2003; Aarts and Caffee, 2005). The main reason for this discrepancy is that the software does not take into account individual anatomical differences, i.e. ear canal volume and …

Effects Of Speech Signal Type And Attention On Acceptable Noise Level In Elderly, Hearing-Impaired Listeners, Jennifer Susan Mundorff

Dissertations, 2014-2019

The primary objective of this study was to determine if acceptable noise levels (ANLs) in elderly, hearing-impaired listeners were dependent on speech intelligibility and listener attention levels. Acceptable noise levels (ANLs), expressed in decibels, is defined as the maximum background noise level that is acceptable while listening to and following a story. Connected speech test (CST) sentences were recorded with clear speech, conversational speech and temporally altered, fast-rate speech. Thirty-five, elderly, hearing-impaired individuals (61-97 years, M=75) with symmetrical, bilateral sensorineural hearing loss participated. Most comfortable listening levels (MCL) and background noise level (BNL) measurements were completed for each speech stimulus …

Comparison Of Speech Intelligibility Over The Telephone Using A Hearing Aid Micorphone And Telecoil, Phillip K. Bond

Dissertations, 2014-2019

The purpose of the current study is to determine if the smaller, modern hearing aid has affected the speech intelligibility over the telephone using a telecoil and hearing aid microphone. Six hearing impaired listeners were situated in a quiet office and were asked to repeat aloud Connected Speech Sentences (CST) they heard through the telephone while wearing their hearing aid in telecoil only mode, microphone only mode, and without their hearing aid. The CST sentences were presented in three different signal-to-noise ratios (Quiet, +10dB, & +5dB) with the recorded speech babble of the CST test. It was discovered that the …

The Effect Of Kalman Weighted Filtering And In-Situ Pre-Amplification On The Accuracy And Efficiency Of Abr Threshold Estimation, Julie Kathleen Wheeler

Dissertations, 2014-2019

Auditory brainstem responses (ABRs) are important for acquiring frequency specific information for determination of the degree and type of hearing loss for infants and difficult-to-test populations when behavioral audiometry cannot be carried out. This study investigated the effects of Kalman weighted filtering and in-situ pre-amplification employed by the Vivosonic Integrity V500 ABR system on threshold accuracy and efficiency in an environment of high physiologic noise in comparison to a conventional ABR system which employs a standard artifact rejection paradigm. Auditory brainstem responses were collected using the Vivosonic ABR system and a conventional ABR system both in quiet and in noise …