Walt Jesteadt, Ph.D. - US grants

The primary evidence of reduced frequency selectivity in listeners with sensorineural hearing loss comes from masking studies where these listeners are found to have abnormally high thresholds and abnormally poor speech perception. This proposal outlines a series of studies designed to test the hypothesis that the effect of hearing loss combines with the effect of an external masker in the same way that the effect of one external masker combines with the effect of another. Recent research suggests that most combinations of external maskers produce more masking in listeners with normal hearing than would be predicted from the effects of the individual maskers and that the rules governing effects of combined maskers differ for different types of maskers. Recent models of additivity of masking provide a framework for integrating these diverse results which could be expanded to include effects of sensorineural hearing loss. The proposed work includes further development of models of additivity, further studies of additivity in both normal and impaired listeners, and studies to extend this approach to encompass loudness growth and speech perception. Hearing loss and masking are clearly not equivalent. Learning more about precisely how they differ will lead to a better understanding of both processes and of how they interact with one another.

health science research support; university;

biomedical equipment resource;

We propose to obtain a more basic understanding of disorders of hearing and speech by pursuing five closely related neurobiological and behavioral studies. Project 1 deals with physiological correlates of certain auditory perceptual phenomena. Using the cat as a model, the project tests hypotheses proposed to account for intensity coding, examines the physiological bases of frequency-specific auditory brainstem response (ABR) masking techniques, and investigates CNS processing of speech and perceptually-relevant complex tones. Project II deals with ABR and behavioral measures of peripheral auditory function in humans with an emphasis on issues related to fitting children with hearing aids. This work includes human ABR studies, related psychophysical studies in adults and children, and studies of speech perception through simulated compression hearing aids. Project III deals with neural mechanisms of orofacial and laryngeal control, again using cat as a model. This work includes studies of motor cortical representation of perioral and facial musculature, anatomical and physiological studies of laryngeal innervation and control, and bulbar and suprabulbar modulation of perioral reflexes elicited by mechanical stimuli. Project IV deals with quantitative measures of vocal tract function that are applicable in clinical studies of speech disorders. This work includes studies of fine force control and evoked perioral muscle response, perioral mechano-sensitivity, and trigeminal somatosensory evoked potentials. Project V deals with the genetics of sensorineural hearing loss, applying recombinant DNA marker techniques in an effort to localize the genes for autosomal dominant hearing losses such as those associated with Waardenburg and Usher syndromes. The common goal of these studies is to improve the diagnosis and treatment of communication disorders in children by relating quantitative measures of human hearing and speech to underlying neurobiological function.

biomedical equipment resource; biomedical equipment purchase;

biomedical equipment purchase;

computer system hardware; health science research support; computer center; biomedical facility; computer program /software; personal computers;

The primary evidence of reduced frequency selectivity in listeners with sensorineural hearing loss comes from masking studies where these listeners are found to have abnormally high thresholds and abnormally poor speech perception. This proposal outlines a series of studies designed to test the hypothesis that the effect of hearing loss combines with the effect of an external masker in the same way that the effect of one external masker combines with the effect of another. Recent research suggests that most combinations of external maskers produce more masking in listeners with normal hearing than would be predicted from the effects of the individual maskers and that the rules governing effects of combined maskers differ for different types of maskers. Recent models of additivity of masking provide a framework for integrating these diverse results which could be expanded to include effects of sensorineural hearing loss. The proposed work includes further development of models of additivity, further studies of additivity in both normal and impaired listeners, and studies to extend this approach to encompass loudness growth and speech perception. Hearing loss and masking are clearly not equivalent. Learning more about precisely how they differ will lead to a better understanding of both processes and of how they interact with one another.

DESCRIPTION (provided by applicant): This application requests support for three postdoctoral positions in a multidisciplinary research training program in the area of human communication and its disorders at Boys Town National Research Hospital (BTNRH). The purpose of the program, currently in its 29th year, is to fulfill four basic training needs: 1) advanced research training for applicants who are recent graduates of speech and hearing or communication sciences doctoral programs, 2) training in hearing research and related areas for applicants with strong backgrounds in molecular biology, molecular genetics, and neuroscience, 3) training in human and molecular genetics for those with strong backgrounds in hearing research, and 4) training for applicants who would benefit from additional research experience in a collaborative, research-intensive environment. The training program consists primarily of direct participation by trainees in basic, translational, or clinical research under the sponsorship of one or more experienced, independent Investigators who comprise the Program Faculty. Research at BTNRH is conducted in 18 different laboratories in a wide range of disciplines from molecular biology to language development, but is focused on a narrower range of questions concerning the mechanisms underlying human communication and its disorders. The environment offers a number of unique advantages for such a training program, including: 1) a faculty that consists of 20 basic and clinical scientists to serve as mentors; 2) a critical mass of research trainees, funded by a variety of mechanisms, including the T32 and F32 and R01 grants; 3) a clinical staff with access to a large and varied pediatric and adult patient population; 4) modern, well-equipped laboratories and diagnostic clinics; 5) a stimulating mix of basic, translational, and clinical research projects; and 6) conditions that foster collaborative, multi-disciplinary research. Trainees are selected from PhD's, DSc's, and MD's in areas relevant to ongoing research programs at BTNRH on the basis of their research capabilities and the likelihood of their interacting synergistically with training faculty. Particular attention is paid to identifying and inviting applications to the program by minority candidates. Every effort is made to increase minority participation in the postdoctoral training program and eventually in research related to the mission of the NIDCD.

DESCRIPTION (provided by applicant): The Boys Town National Research Hospital (BTNRH) Core Center has been designed to meet current and anticipated needs in three areas: 1) laboratory computing, 2) use of transgenic and knockout mouse models, and 3) recruitment of human subjects. The first of the proposed research cores, Laboratory Computing, under the direction of Stephen Neely, will provide central support for the unique needs associated with real-time data collection as well as research database support. By making it feasible to share engineering and programming staff across R01s and by providing the additional support required to develop more general data collection and analysis tools, this core will facilitate sharing of software across laboratories both within our facility and with the auditory research community as a whole. The second research core, Transgenic Mouse Models, under the direction of Dominic Cosgrove, will provide support for the use of unique mouse strains in research by providing integrated animal husbandry and genotyping services. The addition of a technician to our Animal Care Facility will allow us to adopt a uniformly high standard of care, implement routine health monitoring, and operate a more effective breeding program. The addition of a technician responsible for genotyping will provide the information required for breeding and research in a timely manner. This core will foster collaboration by facilitating the sharing of mouse strains within the research program. The third research core, Human Subject Recruitment, under the direction of Michael Gorga, will provide better access to specific types of research subjects while maintaining confidentiality. Recruitment of subjects is a major bottleneck in all of our research projects. With a coordinated effort, we not only can achieve a great increase in efficiency within projects, but also can enable collaboration across research projects that will extend the range of the research program. Our current user base includes 10 R01 grants and 5 P01 projects for which 16 senior staff members serve as principal investigators or co-investigators. The list of key personnel includes 4 additional staff members who are likely to join the user base during the five-year cycle of the Core Center.

IMPROVING SPEECH INTERVENTION FOR DEAF CHILDREN The long-range goal of this project is to develop intervention practices that will optimize speech production outcomes for prelingually deafened children, particularly those with cochlear implants (CIs). There is remarkably little scientific evidence to support the treatment approaches used in speech intervention with such children. Data are needed to guide clinicians in selecting the most appropriate treatment goals and most effective treatment procedures. Speech/voice physiologic data from children implanted after four years of age support the need for early and highly focused intervention directed at remediation of their deviant speech/voice characteristics. One aim of this application is to determine if there is a similar need for children who have had fewer years of auditory deprivation. Therefore, the frequency of occurrence of deviant speech/voice behaviors (i.e., negative intraoral air pressures, high fundamental frequencies) for children implanted before age three and after age four will be compared. A second aim is to compare the efficacy of two forms of speech intervention with children with CIs. One form of treatment will include auditory discrimination and speech production activities. The other will focus on speech production only. Speech production and perception outcomes with both forms of treatment will be compared. Other aims will address how the acoustic characteristics of speech production of children with hearing loss (HL) are affected by 1) simultaneous speaking and signing and signed models 2) instruction to speak more clearly and 3) different speech elicitation procedures. These findings will provide information about 1) the ways in which signing and signed input could be adapted to help deaf children learn the most normal speech production patterns possible during intervention 2) the successful and unsuccessful strategies used by children with HL to maximize their intelligibility and 3) the hierarchy of difficulty of tasks that are used during speech intervention with children with HL. The ultimate goal of this application is to contribute to the development of improved intervention procedures so that more deaf children can become intelligible speakers. Such an achievement would expand the social, educational, and vocational opportunities of deaf children.

DESCRIPTION (provided by applicant): The goal of this research program is to develop a better understanding of fundamental aspects of human hearing by characterizing differences in decision processes for three tasks that use the same basic stimuli in different temporal configurations: intensity discrimination, increment detection, and forward masking. The classic and ubiquitous energy detector model of the decision process provides a good account of data for intensity discrimination. An alternative to energy detection, however, is required to account for results obtained in increment detection and forward masking, as well as the majority of other detection and discrimination tasks. Alternative models of the decision process, in particular "template matching", are currently poorly defined and make vague predictions. We will characterize properties of the decision process in these tasks by determining the effects of variability in overall stimulus level and the effects of introducing background noise. Performance measures include adaptive thresholds, psychometric functions, direct measures of internal noise, and the correlation of specific features of stimuli with each subject's response on individual trials. The specific aims are: 1) to determine the relation between peripheral nonlinearity and the slopes of psychometric functions;2) to compare decision processes in intensity discrimination and increment detection;3) to determine the effects of noise on intensity discrimination, increment detection and forward masking;and 4) to develop and compare direct measures of internal noise. This research effort will result in a better characterization of alternative decision processes, a detailed test of specific features of the decision process associated with each of the three basic psychophysical tasks considered here, measures of internal noise appropriate to each task, and a better understanding of the interaction of peripheral compression and internal noise in multi-stage models of masking.

Area; Auditory; Auditory Prosthesis; Binding Sites; Center Core Grants; Chemicals; Childhood; Clinic; Clinical; Clinical Research; Clinical Services; Clinical Study; Cochlear Implants; Cochlear Prosthesis; Collaborations; Combining Site; Communication; Deafness; Diagnostic Services; E-Mail; Electronic Mail; Email; Ethics Committees, Research; Evaluation; Genetic; Goals; Government regulations; Graefe-Usher syndrome; Grant; Hallgren syndrome; Hearing; Hearing Aids; IACUC; IRBs; Individual; Institution; Institutional Animal Care and Use Committee; Institutional Review Boards; Intellectual Property; Internet; Investigators; Laboratories; Language; Library Services; Medical center; Minor; Mission; Nebraska; P-30; P-30 Protein; P30; P30 Mechanism; P30 Program; P30 Protein; Philosophy; Postdoc; Postdoctoral Fellow; Programs (PT); Programs [Publication Type]; Qualifying; Radiation; Reactive Site; Recruitment Activity; Research; Research Associate; Research Ethics Committees; Research Personnel; Research Support; Researchers; Retinitis pigmentosa-deafness syndrome; SCHED; Safety; Schedule; Scientist; Sensory; Series; Services; Site; Source; Speech; Structure; Students; Time; Translational Research; Translational Research Enterprise; Translational Science; Universities; Usher Syndrome; Usher syndrome (US); Usher's syndrome; WWW; diagnosis service; dystrophia retinae pigmentosa-dysostosis syndrome; dystrophia retinae pigmentosa-dysostosis syndrome (DRD); dystrophia retinae-dysacousis syndrome; hearing perception; interest; member; pediatric; post-doc; post-doctoral; programs; ranpirnase; ray (radiation); recruit; rehabilitation service; retinitis pigmentosa-congenital deafness syndrome; sound perception; translation research enterprise; web; world wide web

DESCRIPTION (provided by applicant): The goal of the Short-Term Research Training Program for Au.D. Students at the Boys Town National Research Hospital (BTNRH) is to give six Au.D. students per year the opportunity to pursue a full-time (40 hours per week) hands-on clinical or translational research experience in the hearing sciences over a three-month period. Each trainee will be involved in the conduct of a specific research project, working in one of 10 BTNRH NIH-funded laboratories currently carrying out clinical and translational research directly related to audiology. Trainees will work closely with BTNRH faculty mentors who have extensive experience working in a clinically oriented, multidisciplinary research environment. Prior to participation in a research project, trainees will complete the CITI training course related to research involving humans as research subjects. In addition, they will participate in a course on responsible conduct in research which will meet over the course of their internship at BTNRH. Trainees will attend colloquia and journal groups, and will be exposed to a wide range of BTNRH laboratories, in addition to the one in which they have primary interest, including laboratories involved in basic research. They will benefit from available support services, including cores devoted to laboratory computing and subject recruitment, and from the presence of postdoctoral fellows who work in many of the laboratories in which predoctoral Au.D. students will be trained. Postdoctoral fellows, many of whom will go on to academic careers, will benefit by participating with faculty mentors in the training of these students. In conducting the proposed program, the BTNRH faculty will benefit from their experience in providing short- and long-term clinical training, short-term research training for undergraduates from underrepresented minorities, and from participation as faculty in the Au.D. and Ph.D. programs at the University of Nebraska - Lincoln. Trainees in the Short-Term Research Training Program will be recruited from Au.D. programs nationally. To date, 19 programs have provided letters of interest. This program will benefit public health by improving the training of audiologists who will be providing services to the public in medical centers, clinics, and schools.

DESCRIPTION (provided by applicant): The Core Center for Communication Disorders (CCCD) will increase the efficiency of qualifying investigators and promote collaboration among a wide range of research programs at the Boys Town National Research Hospital (BTNRH) and neighboring academic institutions by providing Core support in three areas. The Laboratory Computing and Biostatistics Core (LCBC), under the direction of Stephen Neely, will continue to support research programs by: 1) providing troubleshooting and software development that enables research productivity;2) developing and maintaining useful software packages that benefit multiple laboratories;and 3) providing expert assistance in the use of research hardware and software. With the addition of a biostatistics resource, the LCBC will provide essential services to all CCCD research programs. The new Research Synergy Core (RSC), under the direction of Barbara Morley and Mary Pat Moeller, will facilitate interactions within a large group of investigators at BTNRH and neighboring institutions by: 1) fostering scientific collaboration through a multifaceted, interdisciplinary program of research and information sharing;2) fostering the integration of new ideas and research technologies by establishing affinity groups;and 3) reducing barriers to collaboration by identifying opportunities for resource sharing and other forms of interdependence across laboratories and institutions. The Human Research Subjects Core (HRSC), under the direction of Michael Gorga, will continue to support research with human subjects by: 1) increasing the efficiency, with which potential subjects are recruited, including minority subjects, by maintaining and expanding a database of individuals who have expressed an interest in participating in research;2) assisting investigators in assuring that they are in compliance with local and national regulations;and 3) assisting investigators in the preparation of IRB protocols, IRB and NIH progress reports and in the proper storage and handling of consent forms and related documents. The current CCCD user base includes nine R01grants, but there are more than 20 additional investigators at BTNRH and neighboring institutions with a history of NIH funding and an interest in communication disorders research that can provide the critical mass necessary for increased efficiency and effective collaborations.

The proposed Core Center for Communication Disorders (CCCD) differs from our generic Core Center of the previous two cycles in that it has a research base that includes faculty members at the University of Nebraska - Lincoln (UNL) and Creighton University Medical Center (CUMC) as well as the Boys Town National Research Hospital (BTNRH). Geographic expansion of the base was not necessary to qualify for the current level of funding or to provide a sufficient number of users for any given core, but it will allow us to develop a more dynamic, growth-oriented Core Center. Our goal is to achieve further expansion that would include grants from the University of Nebraska Medical Center (UNMC) and the University of Nebraska at Omaha (UNO) as well as CUMC and UNL as part of the future research base. The larger, multi-institutional center will require greater care in the allocation of center resources than was necessary when the Core Center and the BTNRH research program were synonymous with one another and the same individual served as director of both. Under Approach, we outline the distinctions to be made between allocation of resources for members of the research base and the potential base, the governance structure of the CCCD that will monitor core performance and budgets, and the processes that will be used to make adjustments where necessary. Our prior experience suggests that the ongoing cores of the CCCD will play a significant role in increasing efficiency and collaboration within the research base. We can achieve further increases in both efficiency and collaboration by reaching out to the larger group of programs in the potential research base. This will benefit the programs in the current base at least as much as it will benefit the new programs because it will broaden the scope of the programs conducting research related to communication disorders. The growth of communication disorders research at BTNRH and the neighboring institutions is dependent on the Core Center running smoothly. We have the necessary experience and ties among institutions to develop administrative procedures that will insure success.

DESCRIPTION (provided by applicant): The goal of this research program is to establish a better framework for the use of loudness data in hearing-aid design and ultimately hearing-aid fitting. Several hearing-aid fitting algorithms attempt to restore normal loudness or reduce peaks in loudness, but there is no consensus on appropriate procedures that would enable researchers, engineers or clinicians to verify the extent to which these goals were met. Furthermore, the lack of data on which to base the rules governing the loudness of broadband sounds in listeners with normal hearing (NH) makes it impossible to provide an adequate specification of what restoration of normal loudness in listeners with sensorineural hearing loss (SNHL) would entail. We will explore the use of perceptual weights to establish the contribution of individual frequency bands to the total loudness of broadband sounds. This methodology will allow us to test the basic assumptions underlying current loudness models. The proposed studies are grouped under three specific aims. The first will test the hypothesis that the relation among results obtained with different measurement procedures are independent of the degree of hearing loss. The goal of this aim is to achieve consensus on methods to measure loudness. The second aim will use perceptual weights to test the hypothesis that the contribution of specific frequencies to the total loudness of broadband sounds is influenced by hearing loss. The goal is to explore the effects of level and hearing loss on the specific loudness of broadband sounds, including noise with the long-term spectrum of speech. The final aim will apply methods and insights developed in the course of work on the first two aims to measurements of loudness experienced by new hearing-aid users without and with the amounts of amplification provided by their hearing aids. The studies are designed to assess the extent to which the loudness goals of hearing-aid fitting strategies are met and to explore the effect of acclimatization to hearing aids on loudness perception. The current ANSI standard model of loudness and variations of it guided the design of experiments. The proposed studies are expected to lead to improvements of existing models that will better predict the loudness percepts of individuals with hearing loss, thus potentially leading to better intervention strategies.

DESCRIPTION (provided by applicant): With the widespread success of universal newborn hearing screening (UNHS) programs, it is now possible to identify hearing loss at birth and initiate amplification in early infancy. The ability to identify hearing loss at birth, however, has made the gaps in our knowledge more obvious. The overall goal of the proposed studies is to gain a better understanding of the challenges faced and the unique needs of young children with sensorineural hearing loss. Aim 1 will assess the relative benefit of an extended bandwidth hearing-aid vs. a frequency-lowering scheme to improve the audibility of high-frequency speech components for children with hearing loss. It is hypothesized that the benefit derived from these two approaches will vary as a function of degree and configuration of hearing loss. Results will provide new information regarding optimum amplification strategies for individuals with varying degrees and configurations of hearing loss. Aim 2 will examine the ability of children with and without hearing loss to perceive speech in adverse listening environments. It is hypothesized that performance will be poorer for the hearing-impaired group and that fast-acting compression will degrade performance relative to slow- acting compression. Results will provide a better understanding of children's ability to perform complex listening tasks in noise and how amplification strategies support or fail to support their perceptual strategies. Aim 3 will examine the relative contribution of acoustic-phonetic, phonotactic and language- based cues to speech perception for normal-hearing and hearing-impaired children. It is hypothesized that the patterns of reliance on language-based cues (e.g., filling in unheard acoustic-phonetic details by relying on the language context) will differ between the normal-hearing and hearing-impaired children and that developmental changes in the use of these cues will occur more rapidly in the normal-hearing group. Results will increase our understanding of individual differences in the use of perceptual strategies, the extent to which these two groups rely on language-based processes in difficult listening situations, and how these divergent strategies influence speech perception.

DESCRIPTION (provided by applicant): The goal of the Center for Perception and Communication in Children (CPCC), a COBRE at the Boys Town National Research Hospital (BTNRH) in Omaha, Nebraska, is to expand the range of the current research program by providing a unique environment for the development of junior faculty who have an interest in understanding the consequences of childhood hearing loss for speech and language perception and processing, and ultimately describing performance of children with hearing loss in the real world. Our goal is to broaden the research program, building on its current emphasis on peripheral function in the auditory system to include state-of-the-art work on more complex issues such as the impact of hearing loss on performance in real-world environments including classrooms, the contributions of bottom-up and top down processing in children learning English as a second language, integration of visual and auditory information in speech and language acquisition, the adjustment of hearing-aid properties to promote development of temporal processing and the consequences for visual processing of vestibular deficits associated with hearing loss. Research on these topics will be facilitated by an Administration Core that will coordinate interaction with an External Advisory Committee and external mentors, a Technical Core that will provide support for hardware and software development, signal processing and room-acoustics issues and a Clinical Measurement Core that will collect clinical data, implement quality assurance procedures and assist with selection and interpretation of clinical measures. The CPCC will benefit from combined research experience of the senior faculty who will serve as core directors and mentors and from the unique patient resources and translational research environment at BTNRH. Future plans call for continued expansion of the research program to include work on speech/ language and cognitive function in children with normal hearing, taking advantage of neural imaging facilities currently under development.

Acoustics; Auditory; Centers of Research Excellence; Child; Communication; Core Facility; design; Environment; Evoked Potentials; Faculty; Family member; Funding; Future; Laboratories; Measures; Perception; Phase; Play; Plumbing; Recruitment Activity; Role; simulation; sound; Testing; Visual; Work;

The Administration Core will provide mechanisms for management of resources within the Center for Perception and Communication in Children (CPCC), a COBRE at the Boys Town National Research Hospital. The goal of the CPCC is to expand the existing research program to address issues concerning the development of perception and communication in children with hearing loss as well as those with normal hearing, by promoting development of independent complementary research programs by members of the junior faculty within a cohesive center environment. The Administration Core will contribute to this effort by: 1) conducting periodic assessments of scientific progress; 2) coordinating and evaluating a mentoring program; and 3) performing other essential management functions required to develop and maintain a cohesive center. These include: 1) development of programs to create a cohesive environment; 2) monitoring project and core budgets; 3) creating a program for outside speakers and consultants; 4) development of a common resource sharing plan; 5) coordinating preparation of annual reports; 6) making travel arrangements for members of the Center, external advisors and external mentors; and 7) overall program evaluation and development of a common Resource Sharing plan.