Low-Frequency Vowel Formant Discrimination in Hearing-Impaired Listeners

1970 ◽  
Vol 13 (2) ◽  
pp. 347-359 ◽  
Author(s):  
J. M. Pickett ◽  
J. Mártony
Keyword(s):  
Low Frequency ◽  
Discrimination Performance ◽  
Frequency Discrimination ◽  
Auditory Discrimination ◽  
Frequency Change ◽  
Adaptive Procedure ◽  
Sensation Level ◽  
Formant Frequency ◽  
Vowel Formant ◽  
Measure Of Discrimination

Measurements of vowel formant discrimination were made on 6 listeners with severe-to-profound sensorineural hearing losses and compared with discrimination in 4 normal listeners. The measure of discrimination was the size of the threshold for a frequency change in the formant of a synthetic vowel. An adaptive procedure was used to locate threshold. Results indicated that, at two low formant locations, 205 and 275 Hz, sensorineural discrimination was equal to normal; at 400 and 875 Hz, however, the sensorineural subjects had less discrimination than normal. Learning to maximum discrimination performance was slow for the sensorineural subjects at the two higher formant locations. Formant frequency discrimination appeared to be insensitive to changes in sensation level. Tactual discrimination tests with the vowel stimuli indicated that the obtained performance levels for very poor discrimination may have reflected tactual discrimination rather than auditory discrimination.

Intelligibility of Time-Compressed CNC Monosyllables

1972 ◽  
Vol 15 (2) ◽  
pp. 340-350 ◽  
Author(s):  
Daniel S. Beasley ◽  
Shelley Schwimmer ◽  
William F. Rintelmann
Keyword(s):  
Young Adults ◽  
Compression Ratio ◽  
Discrimination Performance ◽  
Normal Hearing ◽  
Auditory Discrimination ◽  
Sensation Level ◽  
Time Compression

The effects of time-compressed monosyllabic CNCs on the auditory discrimination performance of 96 young adults with normal hearing were studied. Five conditions of time compression, 30% through 70% in 10% steps, plus a 0% control condition were presented at four sensation levels (8, 16, 24, and 32 dB). Ear presentation and list version were counterbalanced with these factors. Results indicated that intelligibility was inversely related to time-compression ratio and directly related to sensation level. Ear and list effects were minimal.

scholarly journals Magnetoelastic Coupling and Delta-E Effect in Magnetoelectric Torsion Mode Resonators

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2022
Author(s):  
Benjamin Spetzler ◽  
Elizaveta V. Golubeva ◽  
Ron-Marco Friedrich ◽  
Sebastian Zabel ◽  
Christine Kirchhof ◽  
...  
Keyword(s):  
Low Frequency ◽  
High Sensitivity ◽  
Element Model ◽  
Mode Number ◽  
Frequency Change ◽  
General Description ◽  
Resonance Modes ◽  
Field Sensor ◽  
Magnetic Sensitivity ◽  
Bending Modes

Magnetoelectric resonators have been studied for the detection of small amplitude and low frequency magnetic fields via the delta-E effect, mainly in fundamental bending or bulk resonance modes. Here, we present an experimental and theoretical investigation of magnetoelectric thin-film cantilevers that can be operated in bending modes (BMs) and torsion modes (TMs) as a magnetic field sensor. A magnetoelastic macrospin model is combined with an electromechanical finite element model and a general description of the delta-E effect of all stiffness tensor components Cij is derived. Simulations confirm quantitatively that the delta-E effect of the C66 component has the promising potential of significantly increasing the magnetic sensitivity and the maximum normalized frequency change ∆fr. However, the electrical excitation of TMs remains challenging and is found to significantly diminish the gain in sensitivity. Experiments reveal the dependency of the sensitivity and ∆fr of TMs on the mode number, which differs fundamentally from BMs and is well explained by our model. Because the contribution of C11 to the TMs increases with the mode number, the first-order TM yields the highest magnetic sensitivity. Overall, general insights are gained for the design of high-sensitivity delta-E effect sensors, as well as for frequency tunable devices based on the delta-E effect.

Development of a Pitch Discrimination Screening Test for Preschool Children

2016 ◽  
Vol 27 (04) ◽  
pp. 281-292
Author(s):  
Maria Kulick Abramson ◽  
Peter J. Lloyd
Keyword(s):  
Preschool Children ◽  
Specific Language Impairment ◽  
Normative Data ◽  
Frequency Discrimination ◽  
Auditory Discrimination ◽  
Auditory Memory ◽  
Pitch Discrimination ◽  
Choice Response ◽  
Typically Developing ◽  
Cross Sectional

Background: There is a critical need for tests of auditory discrimination for young children as this skill plays a fundamental role in the development of speaking, prereading, reading, language, and more complex auditory processes. Frequency discrimination is important with regard to basic sensory processing affecting phonological processing, dyslexia, measurements of intelligence, auditory memory, Asperger syndrome, and specific language impairment. Purpose: This study was performed to determine the clinical feasibility of the Pitch Discrimination Test (PDT) to screen the preschool child’s ability to discriminate some of the acoustic demands of speech perception, primarily pitch discrimination, without linguistic content. The PDT used brief speech frequency tones to gather normative data from preschool children aged 3 to 5 yrs. Research Design: A cross-sectional study was used to gather data regarding the pitch discrimination abilities of a sample of typically developing preschool children, between 3 and 5 yrs of age. The PDT consists of ten trials using two pure tones of 100-msec duration each, and was administered in an AA or AB forced-choice response format. Study Sample: Data from 90 typically developing preschool children between the ages of 3 and 5 yrs were used to provide normative data. Data Analysis: Nonparametric Mann–Whitney U-testing was used to examine the effects of age as a continuous variable on pitch discrimination. The Kruskal–Wallis test was used to determine the significance of age on performance on the PDT. Spearman rank was used to determine the correlation of age and performance on the PDT. Results: Pitch discrimination of brief tones improved significantly from age 3 yrs to age 4 yrs, as well as from age 3 yrs to the age 4- and 5-yrs group. Results indicated that between ages 3 and 4 yrs, children’s auditory discrimination of pitch improved on the PDT. The data showed that children can be screened for auditory discrimination of pitch beginning with age 4 yrs. Conclusions: The PDT proved to be a time efficient, feasible tool for a simple form of frequency discrimination screening in the preschool population before the age where other diagnostic tests of auditory processing disorders can be used.

scholarly journals Hearing at threshold intensities: by slow mechanical traveling waves or by fast cochlear fluid pressure waves

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Haim Sohmer
Keyword(s):  
Soft Tissue ◽  
Hair Cells ◽  
Traveling Wave ◽  
Basilar Membrane ◽  
Fluid Pressure ◽  
Low Frequency ◽  
Frequency Discrimination ◽  
Outer Hair Cells ◽  
Common Mechanism ◽  
Frequency Stimulation

The three modes of auditory stimulation (air, bone and soft tissue conduction) at threshold intensities are thought to share a common excitation mechanism: the stimuli induce passive displacements of the basilar membrane propagating from the base to the apex (slow mechanical traveling wave), which activate the outer hair cells, producing active displacements, which sum with the passive displacements. However, theoretical analyses and modeling of cochlear mechanics provide indications that the slow mechanical basilar membrane traveling wave may not be able to excite the cochlea at threshold intensities with the frequency discrimination observed. These analyses are complemented by several independent lines of research results supporting the notion that cochlear excitation at threshold may not involve a passive traveling wave, and the fast cochlear fluid pressures may directly activate the outer hair cells: opening of the sealed inner ear in patients undergoing cochlear implantation is not accompanied by threshold elevations to low frequency stimulation which would be expected to result from opening the cochlea, reducing cochlear impedance, altering hydrodynamics. The magnitude of the passive displacements at threshold is negligible. Isolated outer hair cells in fluid display tuned mechanical motility to fluid pressures which likely act on stretch sensitive ion channels in the walls of the cells. Vibrations delivered to soft tissue body sites elicit hearing. Thus, based on theoretical and experimental evidence, the common mechanism eliciting hearing during threshold stimulation by air, bone and soft tissue conduction may involve the fast-cochlear fluid pressures which directly activate the outer hair cells.

scholarly journals Functional Role of Auditory Cortex in Frequency Processing and Pitch Perception

2002 ◽  
Vol 87 (1) ◽  
pp. 122-139 ◽  
Author(s):  
Mark Jude Tramo ◽  
Gaurav D. Shah ◽  
Louis D. Braida
Keyword(s):  
Auditory Cortex ◽  
Pure Tone ◽  
Current Knowledge ◽  
Frequency Discrimination ◽  
Frequency Selectivity ◽  
Frequency Resolution ◽  
Frequency Change ◽  
Fine Grained ◽  
Difference Thresholds ◽  
Frequency Processing

Microelectrode studies in nonhuman primates and other mammals have demonstrated that many neurons in auditory cortex are excited by pure tone stimulation only when the tone's frequency lies within a narrow range of the audible spectrum. However, the effects of auditory cortex lesions in animals and humans have been interpreted as evidence against the notion that neuronal frequency selectivity is functionally relevant to frequency discrimination. Here we report psychophysical and anatomical evidence in favor of the hypothesis that fine-grained frequency resolution at the perceptual level relies on neuronal frequency selectivity in auditory cortex. An adaptive procedure was used to measure difference thresholds for pure tone frequency discrimination in five humans with focal brain lesions and eight normal controls. Only the patient with bilateral lesions of primary auditory cortex and surrounding areas showed markedly elevated frequency difference thresholds: Weber fractions for frequency direction discrimination (“higher”—“lower” pitch judgments) were about eightfold higher than Weber fractions measured in patients with unilateral lesions of auditory cortex, auditory midbrain, or dorsolateral frontal cortex; Weber fractions for frequency change discrimination (“same”—“different” pitch judgments) were about seven times higher. In contrast, pure-tone detection thresholds, difference thresholds for pure tone duration discrimination centered at 500 ms, difference thresholds for vibrotactile intensity discrimination, and judgments of visual line orientation were within normal limits or only mildly impaired following bilateral auditory cortex lesions. In light of current knowledge about the physiology and anatomy of primate auditory cortex and a review of previous lesion studies, we interpret the present results as evidence that fine-grained frequency processing at the perceptual level relies on the integrity of finely tuned neurons in auditory cortex.

scholarly journals Acoustic Change Complex (ACC) using Speech and Non-Speech Stimuli in Normal Hearing Children

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
W A Elkholy ◽  
D M Hassan ◽  
N A Shafik ◽  
Y E K Eltoukhy
Keyword(s):  
Auditory Evoked Potentials ◽  
Temporal Frequency ◽  
Normal Hearing ◽  
Auditory Discrimination ◽  
Auditory Evoked Potential ◽  
Frequency Change ◽  
Spectral Change ◽  
Speech Stimuli ◽  
Significant Difference ◽  
Hearing Children

Abstract Background Cortical auditory evoked potentials (CAEPs) are brain responses evoked by sound and are processed in or near the auditory cortex. ACC is a cortical auditory evoked potential (P1-N1-P2) elicited by a change within an ongoing sound stimulus. Objective To reach the best stimuli that can elicit ACC and act as an objective tool for assessment of cortical auditory discrimination in normal hearing children. Patients and Methods The present study was originally designed to standardize ACC evoked response in 41 children aged from 2 to 10 years. The mean age in our study group was 6.2 years with no significant difference between males and females. Stimuli used in this study were specifically designed to be used by AEP equipment that is capable of uploading short duration stimuli (500 msec.), thus can be used in a regular AEP lab. ACC was elicited by three groups of stimuli. Gap-in-tones stimuli represent temporal change (6, 10, 30 and 50 msec. gap introduced to 1000 Hz tone separately), frequency pairs stimuli represent frequency change (2%, 4%, 10% and 25% change from base freq. 1000 Hz) and vowel pairs stimuli represent spectral change (/i-u/, /u-i/, /i-a/. /a-i/, /u-a/, /a-u/). ACC response parameters were compared when using the different stimuli as regards percent detectability, morphology, latency and amplitude. Results Gap-in-tones at 6 msec. and 4% frequency change could elicit ACC response in 100% of subjects. For spectral change, /u-i/ was the highest in eliciting ACC (78%) followed by /i-u/ (68.2%) then /a-i/ (58.5%). ACC had the same morphology of the onset response in the majority of subjects, with longer latency and smaller amplitude. ACC amplitude is a better indicator of cortical discrimination compared to latency because it is consistently affected by magnitude of change. Conclusion ACC is a good electrophysiological tool for cortical auditory discrimination for temporal, frequency and spectral change.

Sign in / Sign up

Export Citation Format

Share Document