Search results for " Evoked Response"
showing 8 items of 8 documents
Extra-tympanic electrocochleography in a normal population. A descriptive study.
2015
Abstract Introduction and objectives Extra-tympanic electrocochleography is an electrophysiological register obtained after stimulating the cochlea with an audible stimulus. This stimulus is applied using an earphone over the external auditory canal, while the electrical activity is registered by surface electrodes. There are few studies that analyse normal electrocochleography in our environment. Thus, the main objective of our study was to regularise the values obtained with electrocochleography in ears without any otoneurological diseases. We explain in detail the process of obtaining the register. Methods Sixty healthy ears were studied by extratympanic electrocochleography. Statistical…
Comparison of Electrocochleography and Video Head Impulse Test findings in Vestibular Migraine and Ménière Disease: A Preliminary Study
2020
OBJECTIVES: To evaluate electrophysiological findings among patients with vestibular migraine (VM) and to compare them with those of patients suffering from definite Ménière disease (MD) without migraine. MATERIALS and METHODS: Twenty-one consecutive patients suffering from VM were enrolled; all subjects were selected according to the criteria proposed by the Bàràny Society for Neuro-otology. Each patient underwent a careful otological and neurotological examination. After completing a questionnaire regarding migraine and vertigo complaints, they were assessed by audiometric testing, video head impulse test (vHIT), and elec-trocochleography (EcochG). Data were compared with those of 21 pati…
On the threshold of effective well infant nursery hearing screening in Western Sicily.
2012
Abstract Objective To determine the feasibility and effectiveness of well-infant nursery hearing screening programme for the early identification of hearing impairment, based on transient evoked otoacoustic emission (TEOAE) with a high “screen sensitivity” reducing the number of more expensive secondary level exams. Methods The newborns were screened by non-specialist health workers in well babies nursery at the twentieth day of life for 6 years consecutive. Based on PASS/FAIL criteria and presence/absence of audiological risk factors the newborns were divided into four groups each one with its personal step programme: G1 – PASS without risk factor, free to go home; G2 – PASS with risk fact…
Auditory event-related potentials show altered hemispheric responses in dyslexia
2011
Dyslexia is characterized by deficits in phonological processing abilities. However, it is unclear what the underlying factors for poor phonological abilities or speech sound representations are. One hypothesis suggests that individuals with dyslexia have problems in basic acoustic perception which in turn can also cause problems in speech perception. Here basic auditory processing was assessed by auditory event-related potentials recorded for paired tones presented in an oddball paradigm in 9-year-old children with dyslexia and a familial background of dyslexia, typically reading children at familial risk for dyslexia and control children without risk for dyslexia. The tone pairs elicited …
Audiologic profile of infants at risk: experience of a Western Sicily tertiary care centre.
2012
Objective: To identify the incidence of sensorineural hearing loss (SNHL) on infant at risk and to classify the degree and type of hearing loss describing the main causes associated in Western Sicily. To compare single TEOAE and combined TEOAE/ABR techniques studying the referral rate, the false-positive and false-negative rates through concordance test (κ coefficient), sensitivity (TPR) and specificity (TNR) for each protocol. Methods: From January 2010 to June 2011, 412 infants at risk, ranging from 4 to 20 weeks of life, transferred to Audiology Department of Palermo from the births centers of Western Sicily, underwent to audiological assessment with TEOAE, tympanometry and ABR. The foll…
Neural Mechanisms Underlying Human Auditory Evoked Responses Revealed By Human Neocortical Neurosolver
2022
Funding Information: This study was supported by National Institutes of Health (Grant Nos. NIBIB RO1 EB022889, NIMH RO1 MH106174). Publisher Copyright: © 2021, The Author(s). Auditory evoked fields (AEFs) are commonly studied, yet their underlying neural mechanisms remain poorly understood. Here, we used the biophysical modelling software Human Neocortical Neurosolver (HNN) whose foundation is a canonical neocortical circuit model to interpret the cell and network mechanisms contributing to macroscale AEFs elicited by a simple tone, measured with magnetoencephalography. We found that AEFs can be reproduced by activating the neocortical circuit through a layer specific sequence of feedforwar…
Vitamin A deficiency increases noise susceptibility in guinea pigs.
1990
The effect of vitamin A deficiency in guinea pigs on noise-induced temporary threshold shift (TTS) was evaluated after short (15 min) acoustic overstimulation with a moderate (90 dB) broad-band white noise. Some guinea pigs were fed ad libitum a purified diet deficient in vitamin A (VAD group) until biochemical signs of deficiency occurred. A second, control group (VA group) received the same diet as well as 100 IU vitamin A daily by pharyngeal tube. Cochlear potentials were recorded by special computerized equipment using implanted electrodes. Before acoustic stimulation, a baseline value was determined with a test stimulus [90 dBA (A-filter according to usual DIN instructions)] correspond…
Otoacoustic emissions: a new method to diagnose hearing impairment in children.
1993
Otoacoustic emissions (OAEs) are epiphenomena of sensitive, amplifying processes during hearing which can be detected in persons with normal inner ear function. They originate from the cochlea and are interpreted as an energy leakage of cochlear processes, perhaps resulting from active outer hair cell movements. OAEs travel from the cochlea through the middle ear to the external auditory canal where they can be detected using sensitive miniature microphones. Transient evoked (TEOAE) tests allow to otoacoustic emissions non-invasively check the integrity of the cochlea. In the neonatal period, registration of OAEs can be accomplished during natural sleep. In infants and neonates TEOAEs can b…