Biomedical subjects

H S Plattsmier

Publications and source records attributed to H S Plattsmier.

6 recordsLinked to original sources

PubMed1988

Temporary threshold shift measured with two psychophysical procedures.

Studies of temporary threshold shift (TTS) typically use classical psychophysical procedures, such as the method of adjustment, which are known to confound the obtained measure of sensitivity with the subject's criterion for response. A distinguishing feature of TTS research is high variability in the postexposure estimates of sensitivity, both within and across subjects and within and across sessions. It is possible that fluctuations in the subject's criterion for response (rather than actual variations in sensitivity) are responsible both for misestimations of the magnitude of the hearing loss induced by exposure to particular intense sounds (the TTS), and for the high variability that is commonly observed. To test this possibility, postexposure recovery of sensitivity was followed using two psychophysical procedures, one acknowledged to be criterion-dependent and the other relatively criterion-free. Within each postexposure session, alternate estimates of sensitivity were obtained with a version of the method of adjustment and with adaptive, two-interval forced-choice. The postexposure estimates of hearing sensitivity obtained with the two procedures were found to differ statistically; however, the preexposure baseline measures differed by essentially identical amounts. Thus, the values of TTS were equivalent with the two psychophysical procedures. Further, the session-to-session variability was found not to be significantly different with the two methods. Thus, for our trained observers at least, differences in pre- and postexposure response criteria did not appear to be a contaminating factor in estimates of TTS, and there was little basis for choice between the two procedures in regard to session-to-session variability.

Adult↗

PubMed1984

Aspirin-induced hearing loss as a model of sensorineural hearing loss.

Performance in forward-masking, temporal-integration, and gap-detection tasks was measured in five normal-hearing subjects before and during a five-day period of aspirin use. The drug regimen was 3.9 g per day, taken in four equal doses at 6-h intervals. In the subjects showing substantial temporary hearing loss induced by the aspirin, (1) forward masking declined at about a normal rate as the masker-to-signal interval was increased, (2) the temporal-integration functions were flatter than normal, and (3) detection of a temporal gap was worse than normal at low sound-pressure levels (SPLs) but was essentially normal at levels above about 60 dB SPL. These aspirin-induced changes in performance are similar to the differences observed between normal listeners and listeners with mild sensorineural hearing loss. Thus, temporary, aspirin-induced hearing loss offers promise as a model condition for sensorineural hearing loss. The advantages offered by this model include all those typically attributed to within-subjects experimental designs, as well as the ability to manipulate the amount of hearing loss. Its primary disadvantages are that the hearing loss is not asymmetrically distributed toward the high-frequency region, as it typically is with sensorineural deafness, and there are large individual differences in the amount of temporary hearing loss induced by fixed doses of aspirin.

Adult↗

PubMed1984

Aspirin abolishes spontaneous oto-acoustic emissions.

Spontaneous oto-acoustic emissions (OAEs) were measured prior to, during, and following administration of aspirin. The dose schedule was three 325-mg tablets every 6 h for a total of 16 doses (3.75 days). In every subject studied, all spontaneous OAEs gradually diminished and then disappeared during the drug regimen. Emissions that were initially small disappeared within 14-20 h of beginning the drug regimen (3-4 doses), while initially large emissions took 40-70 h (7-12 doses) to disappear completely. In contrast, the initial size of an emission appeared unrelated to the time required for it to recover to full strength once drug administration ceased. The recovery process was highly idiosyncratic, with the emissions of some subjects returning to full strength within 24 h, while for other subjects, full recovery required several days. In two subjects having multiple emissions in the same ear, the relative sizes of the different emissions often changed greatly during the disappearance and recovery phases. When small frequency shifts appeared for these subjects, they appeared--and were in the same direction--for each of the multiple emissions. In a related experiment, the spontaneous emission was unchanged in one subject who took a drug that inhibits the intracellular entry of calcium ions (verapamil).

Aspirin↗

PubMed1983

Aspirin can potentiate the temporary hearing loss induced by intense sounds.

UNLABELLED: Aspirin is known to produce a reversible loss of hearing that can be as great as 40 dB, depending upon the dose and the individual subject. Here we show that aspirin-induced losses exacerbate the temporary hearing loss induced by exposure to intense sound. EXPOSUREs that ordinarily produce about 14 dB of temporary threshold shift (TTS) will produce about 18-27 dB of TTS if the listener has been taking 3.9 g of aspirin for the past two days or more. A lesser dose or a shorter duration of use produces a smaller, or no, increment in temporary hearing loss. This greater TTS, and an apparent prolongation of recovery from exposure, make chronic aspirin use ill-advised for people routinely exposed to intense sounds. EXPOSURE: 2500 Hz, 10 min, varying intensity. TTS frequency: 3550 Hz. Psychophysical method: 2IFC, adaptive.

Adult↗

PubMed1983

Frequency patterns of TTS for different exposure intensities.

Temporary threshold shift (TTS) was measured for several different test frequencies following exposure to a 2500-Hz tone. The intensity of the exposure tone was varied from 82 to 97 dB SPL; its duration was 5 or 10 min. In each post-exposure session, TTS was followed for four test frequencies using a method of adjustment. In all cases, the "center of balance" of the TTS pattern moved upward in frequency as exposure intensity increased. This outcome is consistent with the idea of a basalward migration of the traveling-wave envelope with increasing exposure intensity, but the evidence is not unequivocal.

Acoustic Stimulation↗

PubMedDate not supplied

Temporary hearing loss induced by combinations of intense sounds and nonsteroidal anti-inflammatory drugs.

Intense sounds were delivered to 11 subjects with normal hearing both before and during administration of standard doses of four nonsteroidal anti-inflammatory drugs. After four days of aspirin treatment (3.9 g daily), the subjects' resting hearing levels raised by about 10 dB. Administration of intense sounds that had previously been shown to produce about 12 dB of temporary hearing loss added increments of 10 to 15 dB to the aspirin-induced hearing loss. That is, the total temporary hearing loss produced by aspirin plus exposure to intense sound was about 10 to 15 dB greater than that produced by exposure to the intense sound alone. A similar effect was observed for sodium salicylate. After similar administrations of sulindac (400 mg per day) and diflunisal (750 mg per day), there was no corresponding increase in the sound-induced hearing loss. Under certain reasonable assumptions about underlying mechanisms, these findings suggest that persons taking moderate doses of aspirin or sodium salicylate may be at increased risk of noise-induced hearing loss.

Adult↗