Two studies are reported in which the threshold estimates from auditory steady-state response (ASSR) tests are compared to those of click- or toneburst-evoked auditory brainstem responses (ABRs). The first, a retrospective review of 51 cases, demonstrated that both the click-evoked ABR and the ASSR threshold estimates in infants and children could be used to predict the pure-tone threshold. The...

INTRODUCTION Serotonin seems to play a central role in tinnitus. The intensity dependence of auditory evoked potential (IDAP) is considered an index of central serotonergic activity in the auditory cortex. The higher the steepness of the N1/P2 component amplitude-stimulus function slope (N1/P2 ASF slope as calculated by IDAP), the lower the central serotonergic activity. Similarly, the N1 ampli...

The neurofibromatoses with two subclasses known as NF1 and NF2 are two genetically distinct, autosomal dominantly inherited conditions with significant ramifications in the human auditory system. NF1 is a multisystem progressive disorder that can frequently involve portions of the auditory system in diverse and subtle ways and in which no characteristic audiologic findings can be discerned. NF2...

Neurons at higher stages of sensory processing can partially compensate for a sudden drop in peripheral input through a homeostatic plasticity process that increases the gain on weak afferent inputs. Even after a profound unilateral auditory neuropathy where >95% of afferent synapses between auditory nerve fibers and inner hair cells have been eliminated with ouabain, central gain can restore c...

Auditory brain-stem response (ABR) was measured in 40 patients (80 ears) with confirmed hydrocephalus. Eighty-eight percent of these patients showed some form of ABR abnormality. Responses indicative of brain-stem dysfunction consisted of prolonged I-V interwave latency (38%), reduced V/I amplitude ratio (33%), and abnormalities in wave-shape of components III (27%) and V (53%). In addition, 70...

Tinnitus or ringing of the ears is a subjective phantom sensation necessitating behavioral models that objectively demonstrate the existence and quality of the tinnitus sensation. The gap detection test uses the acoustic startle response elicited by loud noise pulses and its gating or suppression by preceding sub-startling prepulses. Gaps in noise bands serve as prepulses, assuming that ongoing...

Background and Objectives The latency of auditory brainstem response (ABR) wave V shifts depending on age, hearing threshold, stimulus intensity. This study was performed to examine the latencies ABR in infants with normal sensorineural loss.Subjects Method retrospective review 318 (539 ears) performed. patients were divided into four groups according age at time test (group A: 0-2 months, grou...

Background and Objectives There is no clear standard for the difference in thresholds of auditory brainstem response (ABR) pure tone audiometry (PTA) when using ABR to evaluate reliability PTA. Therefore, we assessed PTA each frequency. Consequently, present here actual values between two tests that can be used as a reference clinic.Subjects Method We retrospectively results 129 ears. Ears whic...

THE AVERAGED auditory brainstem responses are effectively utilized to determine hearing sensitivity in neonates and infants, ~, 2 and for the detection of brainstem lesions in neuro!ogic disease? In addition, they may also be used as measures of peripheral auditory pathway maturation 4,5 and to monitor the outcome of perinatal asphyxia. 6 Recently, a controversyJhas developed over the condition...

In June 2008, two pygmy killer whales (Feresa attenuata) were stranded alive near Boca Grande, FL, USA, and were taken into rehabilitation. We used this opportunity to learn about the peripheral anatomy of the auditory system and hearing sensitivity of these rare toothed whales. Three-dimensional (3-D) reconstructions of head structures from X-ray computed tomography (CT) images revealed mandib...