Normal Values in Hearing and Balance Testing

* INCLUSION CRITERIA: Healthy adult volunteers: * Healthy adults, aged 18-80 years * Able to provide informed consent * Normal hearing sensitivity, defined as pure-tone thresholds less than or equal to 25 dB HL, or when the pure-tone threshold exceeds 25 dB HL, it must be less than or equal to the median threshold for the appropriate gender- and age-based group, for 250-8000 Hz (Morrell et al, 1996, ISO-7029, 2000). * No air-bone gaps in excess of 10 dB for 500-4000 Hz. * Normal middle ear function as indicated by normal 226 Hz tympanograms bilaterally, defined as middle ear pressure between more or less 100 decaPascals, and peak compensated static compliance between 0.3-1.5 milliliters * American English as a first language for those participating in study tasks evaluating auditory processing. * Able to refrain from caffeine and alcohol for 48 hours before vestibular study sessions because both agents may modify the test results. EXCLUSION CRITERIA: * History of auditory and/or vestibular disorders (e.g., Meniere s syndrome, labyrinthitis). * Evidence of active outer or middle ear disease or anomaly (e.g. otitis media, stenotic ear canal, otorrhea) * History of chronic (fluid in middle ear for more than 4 months) or recurrent otitis media (more than 4 episodes of acute otitis media in one year) * History of ear surgery other than PE tubes * Current PE tubes * History of treatment with ototoxic medications (e.g. cisplatin, aminoglycoside antibiotics) * Unable to discontinue medications that can interfere with vestibular test results for the 48 hours immediately preceding a vestibular study session. These include any and all anti-dizziness medications (such as Antivert), prescription pain medications (such as Percocet), prescription headache medications (such as Imitrex), sleeping pills (such as Ambien), anti-seizure medications (such as Topamax), and/or antihistamines (such as Benadryl). * Current diagnosis from the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) of a psychiatric disorder or on medications for a psychiatric disorder in the past two years, including any or all antidepressants, anxiolytics, or psychostimulant drugs. * Cognitive impairment as evidenced by a score \<26 on the Montreal Cognitive Assessment (MoCA). * Attention deficit hyperactivity disorder (ADHD) as evidenced by a score of greater than or equal than or equal to 4 on the Adult ADHD Self Report Scale (Kessler et al., 2005). * History or diagnosis of a central nervous system disorder, including but not limited to: * Intracranial tumors * Cerebrovascular disease * Degenerative CNS disorder * CNS trauma * Encephalitis * Meningitis * Current diagnosis of speech and/or language disorders, autism, auditory neuropathy, or auditory processing disorder; or in therapy for these disorders in past 2 years. * Reduced visual acuity preventing ability to see the visual targets used for vestibular and balance testing as evidenced by corrected visual acuity worse than 20/25 on a Snellen chart for those participating in vestibular tasks. * Ocular motor impairment preventing ability accurately follow the visual target used for calibration and/or ocular motor tasks for those participating in the vestibular tasks. * Employees and staff of the Audiology Unit, Otolaryngology Branch, NIDCD. * Reduced balance or postural instability as evidenced by a Timed Up and Go score greater than or equal to 11.1 seconds (Whitney et al., 2004) for adults \<65 years of age and \>12.6 seconds for adults 65-80 years of age (Shumway-Cook et al.,2000) and/or Activities-specific Balance Confidence Score \<67% for those participating in vestibular study tasks. Healthy children volunteers: INCLUSION CRITERIA: * Healthy children, aged 5 years-0 months to 17 years-11 months * Normal hearing sensitivity, defined as pure-tone thresholds of 15 dB HL or better for 250-8000 Hz * Normal middle ear function as indicated by normal 226 Hz tympanograms bilaterally, defined as middle ear pressure between more or less 100 decaPascals, and peak compensated static compliance between 0.2-1.5 milliliters * American English as a first language for those participating in study tasks evaluating auditory processing. * Ability to follow the verbal instructions and commands for study tests * Able to refrain from alcohol and caffeine intake for 48 hours before vestibular study sessions because caffeine may modify the test results * Weight greater than 40 pounds for those participating in vestibular tasks that include CDDP EXCLUSION CRITERIA: * History of auditory and/or vestibular disorders (e.g. Meniere syndrome, enlarged vestibular aqueduct). * Evidence of active outer or middle ear disease or anomaly (e.g. otitis media, stenotic ear canal, otorrhea) * History of chronic (fluid in middle ear for more than 4 months) or recurrent otitis media (more than 4 episodes of acute otitis media in one year) * History of ear surgery other than PE tubes * Current PE tubes * History of treatment with ototoxic medications (e.g. cisplatin, aminoglycoside antibiotics) * Unable to discontinue medications that can interfere with vestibular test results for the 48 hours immediately preceding a vestibular study session. These include any and all anti-dizziness medications (such as Antivert), prescription pain medications (such as Percocet), prescription headache medications (such as Imitrex), sleeping pills (such as Ambien), anti-seizure medications (such as Topamax), and/or antihistamines (such as Benadryl). * Current diagnosis from the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) of a psychiatric disorder or on medications for psychiatric disorder in the past two years, including any or all antidepressants, anxiolytics, or psychostimulant drugs. * Cognitive impairment as evidenced by a standard score less than 85 on the Peabody Picture Vocabulary Test (Fourth Edition) * Attention deficit hyperactivity disorder (ADHD) as evidenced by a score of greater than or equal to 6 on the SNAP IV * History or previous diagnosis of a central nervous system disorder, including but not limited to: * Intracranial tumors * Cerebrovascular disease * Degenerative CNS disorder * CNS trauma * Encephalitis * Meningitis * Current diagnosis of speech and/or language disorders or delays, autism, auditory neuropathy, or auditory processing disorder; or in therapy of these disorders in past 2 years. * Reduced visual acuity preventing ability to see the visual targets used for vestibular and balance testing as evidenced by corrected visual acuity worse than 20/25 on a Snellen chart for those participating in vestibular study tasks. * Ocular motor impairment preventing ability to see or accurately follow the visual target used for ocular motor tasks for those participating in the vestibular study tasks. * Reduced balance or postural instability as evidenced by a Timed Up and Go score of greater than or equal to 9.4 seconds for those participating in vestibular study tasks.