John Greer Clark

Effect of kennel noise on hearing in dogs.

OBJECTIVE To evaluate the degree of noise to which kenneled dogs were exposed in 2 typical kennels and to determine whether a measurable change in hearing might have developed as a result of exposure to this noise. ANIMALS 14 dogs temporarily housed in 2 kennel environments. PROCEDURES Noise levels were measured for a 6-month period in one environment (veterinary technical college kennel) and for 3 months in another (animal shelter). Auditory brainstem response testing was performed on dogs in the veterinary kennel 48 hours and 3 and 6 months after arrival. Temporal changes in the lowest detectable response levels for wave V were analyzed. RESULTS Acoustic analysis of the kennel environments revealed equivalent sound level values ranging between 100 and 108 dB sound pressure level for the 2 kennels. At the end of 6 months, all 14 dogs that underwent hearing tests had a measured change in hearing. CONCLUSIONS AND CLINICAL RELEVANCE Results of the noise assessments indicated levels that are damaging to the human auditory system. Such levels could be considered dangerous for kenneled dogs as well, particularly given the demonstrated hearing loss in dogs housed in the veterinary kennel for a prolonged period. Noise abatement strategies should be a standard part of kennel design and operation when such kennels are intended for long-term housing of dogs.

Long‐period fluctuations of CW signals in deep and shallow water

In July 1972, as part of the cooperative studies between the Miami and Michigan Project MIMI research groups, continuous fixed‐system underwater sound propagation tests at 406 Hz were commenced between a sound source off Eleuthera, Bahamas, and receivers at Bermuda, a distance of 1250 km, and at positions intermediate in range with respect to the 1250‐km path. Preliminary studies of long‐period CW transmission fluctuations at Bermuda and at one intermediate position have been completed. The long‐period phase and amplitude fluctuations are qualitatively quite similar to those observed in the Straits of Florida and in other relatively shallow water locations. Phase fluctuations associated with the ocean tides are a marked feature of the data. With averages taken over two‐day time spans, significant variations in the statistical properties of transmission loss have been observed over a five‐month time period. Shorter‐period fluctuations in acoustic phase (time scale of a few minutes to a few hours) have similar characteristics in the deep and shallow water propagation ranges. [The research was supported by Code 412 of the Office of Naval Research.]In July 1972, as part of the cooperative studies between the Miami and Michigan Project MIMI research groups, continuous fixed‐system underwater sound propagation tests at 406 Hz were commenced between a sound source off Eleuthera, Bahamas, and receivers at Bermuda, a distance of 1250 km, and at positions intermediate in range with respect to the 1250‐km path. Preliminary studies of long‐period CW transmission fluctuations at Bermuda and at one intermediate position have been completed. The long‐period phase and amplitude fluctuations are qualitatively quite similar to those observed in the Straits of Florida and in other relatively shallow water locations. Phase fluctuations associated with the ocean tides are a marked feature of the data. With averages taken over two‐day time spans, significant variations in the statistical properties of transmission loss have been observed over a five‐month time period. Shorter‐period fluctuations in acoustic phase (time scale of a few minutes to a few hours) have simi...

Electrodiagnostic Evaluation of Auditory Function in the Dog

Given the high incidence of deafness within several breeds of dogs, accurate hearing screening and assessment is essential. In addition to brainstem auditory evoked response (BAER) testing, 2 other electrophysiologic tests are now being examined as audiologic tools for use in veterinary medicine: otoacoustic emissions and the auditory steady state response (ASSR). To improve BAER testing of animals and ensure an accurate interpretation of test findings from one test site to another, the establishment of and adherence to clear protocols is essential. The ASSR holds promise as an objective test for rapid testing of multiple frequencies in both ears simultaneously.

Visual Discrimination Predicts Naming and Semantic Association Accuracy in Alzheimer Disease

ObjectiveLanguage impairment is a common symptom of Alzheimer disease (AD), and is thought to be related to semantic processing. This study examines the contribution of another process, namely visual perception, on measures of confrontation naming and semantic association abilities in persons with probable AD. MethodsTwenty individuals with probable mild-moderate Alzheimer disease and 20 age-matched controls completed a battery of neuropsychologic measures assessing visual perception, naming, and semantic association ability. Visual discrimination tasks that varied in the degree to which they likely accessed stored structural representations were used to gauge whether structural processing deficits could account for deficits in naming and in semantic association in AD. ResultsVisual discrimination abilities of nameable objects in AD strongly predicted performance on both picture naming and semantic association ability, but lacked the same predictive value for controls. Although impaired, performance on visual discrimination tests of abstract shapes and novel faces showed no significant relationship with picture naming and semantic association. These results provide additional evidence to support that structural processing deficits exist in AD, and may contribute to object recognition and naming deficits. ConclusionsOur findings suggest that there is a common deficit in discrimination of pictures using nameable objects, picture naming, and semantic association of pictures in AD. Disturbances in structural processing of pictured items may be associated with lexical-semantic impairment in AD, owing to degraded internal storage of structural knowledge.

Hearing aid orientation supplement through DVD instruction

The successful selection of hearing instrumentation for new hearing aid users is dependent upon a variety of factors, including an accurate assessment of the physiologic and psychosocial effects of a diagnosed hearing loss and means to measure the acoustic performance and perceived efficacy of the selected technologies. The successful use of hearing instrumentation is dependent upon patient motivation and comprehensive instructions on the use, care, and limitations of personal amplification. The majority of audiologists allot 30 to 45 minutes to the orientation portion of the hearing aid fitting appointment.1,2 While a 30-45 minute period may appear sufficient, research suggests retention of healthrelated information is frequently poor. Kessels3 found that 40%-80% of information provided by healthcare professionals is forgotten by the patient almost immediately, while half of the information that is remembered is often remembered incorrectly. As the amount of information presented to a patient increases, the ability to remember all the pertinent details of that information often decreases, especially for patients 70 years of age and older.4,5 Margolis suggests that new hearing aid users may have difficulty remembering the variety of information given to them at the hearing aid orientation appointment.6 And while the results of Reese and Smith’s research suggest that hearing aid orientation recall may not be a problem for some patients,7 clearly retention of information presented to patients in a healthcare visit is difficult for many. Research indicates that poor congruence between a patient’s functional literacy level and the grade-level equivalency of the providers’ spoken instruction, as well as supplied printed (hearing aid) user guides, contributes to decreased understanding of the provided information.8,9 To address these factors, Pichora-Fuller and Singh suggest that current approaches to rehabilitative audiology need to be revamped in an effort to aid older adults in familiarizing themselves with their new devices.10 Reese and Hnath-Chisolm11 outline several key factors which influence the retention of hearing aid orientation information, while Kessels’ study indicates that a combination of spoken and visual information is best in conveying health-related information to patients. In an interview with Strom, Kochkin suggested that increased counseling time (including visual aids such as a CD-ROM or video) would enhance customer satisfaction exponentially.12

Canine brainstem auditory evoked responses are not clinically impacted by head size or breed

Accurate assessment of canine hearing is essential to decrease the incidence of hereditary deafness in predisposed breeds and to substantiate hearing acuity. The Brainstem Auditory Evoked Response (BAER) is a widely accepted, objective test used in humans and animals for estimation of hearing thresholds and deafness diagnosis. In contrast to humans, testing and recording parameters for determination of normal values for canine hearing are not available. Conflicting information concerning breed and head size effects on canine BAER tests are major contributors preventing this normalization. The present study utilized standard head measurement techniques coupled with BAER testing and recording parameters modeled from humans to examine the effect canine head size and breed have on BAER results. Forty-three adult dogs from fourteen different breeds had head size measurements and BAER tests performed. The mean latencies compared by breed for waves I, II, III, IV, and V were as follows: 1.46±0.49 ms, 2.52±0.54 ms, 3.45±0.41 ms, 4.53±0.83 ms and 5.53±0.43 ms, respectively. The mean wave I-V latency interval for all breeds was 3.69 ms. All dogs showed similar waveform morphology, structures, including the presence of five waves occurring within 11 ms after stimulus presentation and a significant trough occurring after Wave V. All of the waveform morphology for our subjects occurred with consistent interpeak latencies as shown by statistical testing. All animals had diagnostic results within the expected ranges for each wave latency and interwave interval allowing diagnostic evaluation. Our results establish that neither differences in head size nor breed impact determination of canine BAER waveform morphology, latency, or hearing sensitivity for diagnostic purposes. The differences in canine head size do not have a relevant impact on canine BAERs and are not clinically pertinent to management or diagnostic decisions.

Canine Hearing Loss Management

Dog owners and handlers are naturally concerned when suspicion of hearing loss arises for their dogs. Questions frequently asked of the veterinarian center on warning signs of canine hearing loss and what can be done for the dog if hearing loss is confirmed. This article addresses warning signs of canine hearing loss, communication training and safety awareness issues, and the feasibility of hearing aid amplification for dogs.

Long‐range Atlantic acoustic multipath identification

Multipath data from three long‐range (900 km) transmissions are examined. Two of the transmissions follow similar tracks, with one ending in the Gulf  Stream at the receiving end. The third, which is substantially free of Gulf Stream influence, has been extensively studied by Spiesberger et al. [J. Acoust. Soc. Am. 67, 2011–2017 (1980)]. The path structure of the transmission crossing the Gulf Stream was characterized by low S/N and appeared to be unstable. Path identification with ray calculations was attempted for the two transmission channels exhibiting stable multipath with success for the major features of the path structures. Excessive smoothing of the sound‐speed profile which eliminates the influence of the Atlantic 18° water in the upper layers is shown to degrade the identification of early arrivals. The slight curvature of the ocean sound‐speed profile around 4 km of depth also was critical to early arrival identification. The effect of weak range dependence was small while the effect of a grad...

Environmental Assessment of Offshore Wind Power Generation: Effect on a Noise Budget

The construction, operation, and removal of offshore wind power facilities have the potential to increase the levels of noise in the surrounding waters. Increased shipping noise can be associated with all phases of the life cycle of wind farms. Pile driving during platform construction can be short-lived but can introduce very high intensity pulses into the ocean. Operational noise, while at a much lower level, can affect the surrounding area almost continuously for the life of the facility. The removal of wind platforms at the end of their operational life may use explosives, again short-lived but very intense.

Ballroom Music Spillover into a Beluga Whale Aquarium Exhibit

It is not uncommon for modern aquaria to be built with special entertainment areas. There are no known measurements of sound spillover from such entertainment areas into underwater animal exhibits. Entertainment organizations typically prefer to play music for events at 95 and 100 dBA in a ballroom at Georgia Aquarium. Concern over the potential effects of the music and noise on animals in adjacent exhibits inspired an initial project to monitor and compare sound levels in the adjacent underwater exhibits against the typical in-air sound levels of the ballroom. Measured underwater noise levels were compared to modeled levels based on finite element analysis and plane wave transmission loss calculations through the acrylic viewing window. Results were compared with the model to determine how, if at all, the ambient noise level in the Cold Water Quest exhibit changed as a result of music played in the ballroom.