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The purpose of this study was to determine the influence of selected predictive factors, primarily age at fitting of amplification and degree of hearing loss, on auditory-based outcomes in young children with bilateral sensorineural hearing loss.Forty-four infants and toddlers, first identified with mild to profound bilateral hearing loss, who were being fitted with amplification were enrolled in the study and followed longitudinally. Subjects were otherwise typically developing with no evidence of cognitive, motor, or visual impairment. A variety of subject factors were measured or documented and used as predictor variables, including age at fitting of amplification, degree of hearing loss in the better hearing ear, cochlear implant status, intensity of oral education, parent-child interaction, and the number of languages spoken in the home. These factors were used in a linear multiple regression analysis to assess their contribution to auditory-based communication outcomes. Five outcome measures, evaluated at regular intervals in children starting at age 3, included measures of speech perception (Pediatric Speech Intelligibility and Online Imitative Test of Speech Pattern Contrast Perception), speech production (Arizona-3), and spoken language (Reynell Expressive and Receptive Language).The age at fitting of amplification ranged from 1 to 72 mo, and the degree of hearing loss ranged from mild to profound. Age at fitting of amplification showed the largest influence and was a significant factor in all outcome models. The degree of hearing loss was an important factor in the modeling of speech production and spoken language outcomes. Cochlear implant use was the other factor that contributed significantly to speech perception, speech production, and language outcomes. Other factors contributed sparsely to the models.Prospective longitudinal studies of children are important to establish relationships between subject factors and outcomes. This study clearly demonstrated the importance of early amplification on communication outcomes. This demonstration required a participant pool that included children who have been fit at very early ages and who represent all degrees of hearing loss. Limitations of longitudinal studies include selection biases. Families who enroll tend to have high levels of education and rate highly on cooperation and compliance measures. Although valuable information can be extracted from prospective studies, not all factors can be evaluated because of enrollment constraints.

Background: Newborn Hearing Screening (NHS) programs aim to reduce the age of identification and intervention of infants with hearing loss. It is generally accepted that NHS programs achieve that outcome, but few studies have compared children who were screened to those not screened in the same study and during the same time period. This study takes advantage of the emerging screening programs in California to compare children based on screening status on age at intervention milestones. Purpose: The purpose of this study was to compare the outcomes of cohorts of children with hearing loss, some screened for hearing loss at birth and others not screened. Specifically, the measures compared are the benchmarks suggested by the Joint Committee on Infant hearing for determining the quality of screening programs. Study Sample: Records from 64 children with bilateral permanent hearing loss who were enrolled in a study of communication outcomes served as data for this study. Of these children, 47 were screened with 39 failing and 8 passing, and 17 were not screened. Intervention: This study was observational and involved no planned intervention. Data Collection and Analysis: Outcome benchmarks included age at diagnosis of hearing loss, age at fitting of amplification, and age at enrollment in early intervention. Delays between diagnosis and fitting or enrollment were also calculated. Hearing screening status of the children included screened with fail outcome, screened with pass outcome, and not screened. Analysis included simple descriptive statistics, and t-tests were used to compare outcomes by groups: screened/not screened, screened pass/screened failed, and passed/not screened. Results: Children with hearing loss who had been screened as newborns were diagnosed with hearing loss 24.62 months earlier, fitted with hearing aids 23.51 months earlier, and enrolled in early intervention 19.98 months earlier than those infants who were not screened. Screening status did not influence delays in fitting of amplification or enrollment in intervention following diagnosis. Eight of the infants with hearing loss (12.5%) passed the NHS, and the ages at benchmarks of those children were slightly but not significantly earlier than infants who had not been screened. Conclusions: The age at achievement of benchmarks such as diagnosis, fitting of amplification, and enrollment in early intervention in children who were screened for hearing loss is on target with stated goals provided by the Academy of Pediatrics and the Joint Committee on Infant Hearing. In addition, children who are not screened for hearing loss continue to show dramatic delays in achievement of benchmarks by as much as 24 months. Evaluating achievement of benchmarks during the start-up period of NHS programs allowed a direct evaluation of ability of these screening programs to meet stated goals. This demonstrates, unequivocally, that the NHS process itself is responsible for improvements in age at diagnosis, hearing aid fitting, and enrollment in intervention.

A systematic review of literature addressing the question "Is there evidence pointing to optimal signal processing for pediatric hearing aid patients?" was conducted. Key words and authors were used as search terms in five databases, and one textbook appendix was reviewed for related references. The levels of evidence that were accepted comprised randomized controlled trials, nonrandomized controlled trials, cohort, and before/after designs with or without control groups. Two hundred twenty-six articles were identified during the preliminary search with 183 of these eliminated by review of abstracts because they did not meet the search criteria. Forty-three manuscripts were reviewed, with eight meeting the evidence levels and search criteria. The strengths and weaknesses of these studies are highlighted, and the systematic review question is answered in light of these studies. There is evidence to recommend wide dynamic range compression signal processing for pediatric hearing aid users with mild, moderate, and moderately severe sensorineural hearing loss when full-time and consistent audibility is the goal of the hearing aid fitting. Further, there is evidence that audibility across a wide frequency bandwidth as well as across a large range of input levels is essential for pediatric hearing aid users to recognize critical components of the spoken language.

Dementia of the Alzheimer type (DAT) disrupts the function of the central auditory nervous system as a result of temporal lobe pathology. Auditory brain stem response (ABR) and middle latency responses (MLR) were studied in a group of patients with DAT to determine whether a correlate of dementia existed in these electrophysiological potentials. Comparison of absolute and interwave latencies on ABR, and absolute latency and amplitude of the MLR in patients with DAT and normal aged controls showed no significant differences between groups for any measure. Further, no relationship with degree of dementia or temporal lobe involvement, as assessed through dichotic speech recognition studies, and auditory evoked potentials could be demonstrated. It was concluded that the temporal lobe atrophy and hypometabolism seen in DAT is not generally sufficient to disrupt the generating of ABR and MLR potentials; however, slow cortical and cognitive evoked potentials may be more sensitive to central auditory nervous system impairment in DAT.