21 research outputs found
Heart-Kidney Interaction: Epidemiology of Cardiorenal Syndromes
Cardiac and kidney diseases are common, increasingly encountered, and often coexist. Recently, the Acute Dialysis Quality Initiative (ADQI) Working Group convened a consensus conference to develop a classification scheme for the CRS and for five discrete subtypes. These CRS subtypes likely share pathophysiologic mechanisms, however, also have distinguishing clinical features, in terms of precipitating events, risk identification, natural history, and outcomes. Knowledge of the epidemiology of heart-kidney interaction stratified by the proposed CRS subtypes is increasingly important for understanding the overall burden of disease for each CRS subtype, along with associated morbidity, mortality, and health resource utilization. Likewise, an understanding of the epidemiology of CRS is necessary for characterizing whether there exists important knowledge gaps and to aid in the design of clinical studies. This paper will provide a summary of the epidemiology of the cardiorenal syndrome and its subtypes
Differences in fundamental frequency discrimination and frequency modulation detection between complex tones consisting of resolved and unresolved harmonics
Intensity discrimination in hearing
SIGLEAvailable from British Library Lending Division - LD:D55545/85 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Perceptual auditory stream segregation of sequences of complex sounds in subjects with normal and impaired hearing
International audienc
Perceptual auditory stream segregation of sequences of complex sounds in subjects with normal and impaired hearing
The binaural masking level difference: Cortical correlates persist despite severe brain stem atrophy in progressive supranuclear palsy (in press)
Human auditory nerve compound action potentials and long latency responses
The compound action potential (CAP) is followed by a long latency response (LLR), attributable to the post-auricular musculature. The LLR to one pulse may overlap with the CAP to a subsequent one, contributing to the clinically observed reduction in CAP at high pulse rates. Objectives. To measure refractory and other influences on CAPs in humans and guinea pigs. Materials and methods. CAPs were obtained from humans using trans-tympanic and extra-tympanic electrocochleography and from anaesthetized guinea pigs. Stimuli were single pulses presented at a slow rate, pairs of pulses, and 100 ms pulse trains where the inter-pulse interval alternated between 4 and 6 ms. Results. For single pulses, the CAP shape was similar across species. For pairs of pulses, the CAP to the second pulse was smaller than that to the first, and decreased with increasing inter-pulse interval in a way that was similar across species. For pulse trains, CAPs were observed in response to each pulse in the train for the guinea pigs, but not for humans. For both filtered and unfiltered single pulses, there was a large LLR in humans, but not in guinea pigs, with peaks at latencies of 10–12 and 20–25 ms. Posture affected the LLR in a way consistent with the post-auricular response<br/
Behvioral and physiological correlates of temporal pitch perception in electric and acoustic hearing
In the “4–6” condition of experiment 1, normal-hearing (NH) listeners compared the pitch of a bandpass-filtered pulse train, whose inter-pulse intervals (IPIs) alternated between 4 and 6 ms, to that of isochronous pulse trains. Consistent with previous results obtained at a lower signal level, the pitch of the 4–6 stimulus corresponded to that of an isochronous pulse train having a period of 5.7 ms—longer than the mean IPI of 5 ms. In other conditions the IPI alternated between 3.5–5.5 and 4.5–6.5 ms. Experiment 2 was similar but presented electric pulse trains to one channel of a cochlear implant. In both cases, as overall IPI increased, the pitch of the alternating-interval stimulus approached that of an isochronous train having a period equal to the mean IPI. Experiment 3 measured compound action potentials (CAPs) to alternating-interval stimuli in guinea pigs and in NH listeners. The CAPs to pulses occurring after 4-ms intervals were smaller than responses to pulses occurring after 6-ms intervals, resulting in a modulated pattern that was independent of overall level. The results are compared to the predictions of a simple model incorporating auditory-nerve (AN) refractoriness, and where pitch is estimated from first-order intervals in the AN response