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Alexander Ya Supin - One of the best experts on this subject based on the ideXlab platform.
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Rippled Depth Thresholds: Estimates Obtained by Discrimination From Rippled and NonRippled Reference Signals
Acta Acustica united with Acustica, 2019Co-Authors: Alexander Ya Supin, Olga N. Milekhina, Dmitry I. NechaevAbstract:The objective of the study was to better understand of contribution of excitation-pattern and temporal-processing mechanisms of frequency analysis to discrimination of complex-spectrum signals in various discrimination tasks. Using Rippled-spectrum signals, the Ripple depth thresholds were measured as functions of Ripple density under conditions of Rippled or non-Rippled reference signals. With Rippled reference signals, the Ripple depth thresholds were as low as 0.11 at low Ripple densities (2–3 cycles/oct) and rose to 1.0 at a Ripple density of 8.9 cycles/oct. For non-Rippled reference signals, Ripple depth thresholds were nearly the same as for Rippled reference signals at Ripple densities of up to 7 cycles/oct; at Ripple densities of 10 cycles/oct and higher, Ripple depth thresholds rose slowly and reached 1.0 at a Ripple density of 26 cycles/oct. The results hypothetically suggest contributions of the excitation-pattern processing and temporal-processing mechanisms of frequency analysis to discrimination of Rippled signals. The excitation-pattern mechanism featured low depth thresholds at low Ripple densities but could not function at Ripple densities above 10 cycles/oct. The temporal-processing mechanism manifested at higher Ripple densities and non-Rippled reference stimuli.
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Estimates of Ripple-Density Resolution Based on the Discrimination From Rippled and NonRippled Reference Signals.
Trends in hearing, 2019Co-Authors: Dmitry I. Nechaev, Olga N. Milekhina, Alexander Ya SupinAbstract:: Rippled-spectrum stimuli are used to evaluate the resolution of the spectro-temporal structure of sounds. Measurements of spectrum-pattern resolution imply the discrimination between the test and reference stimuli. Therefore, estimates of Rippled-pattern resolution could depend on both the test stimulus and the reference stimulus type. In this study, the Ripple-density resolution was measured using combinations of two test stimuli and two reference stimuli. The test stimuli were Rippled-spectrum signals with constant phase or Rippled-spectrum signals with Ripple-phase reversals. The reference stimuli were Rippled-spectrum signals with opposite Ripple phase to the test or nonRippled signals. The spectra were centered at 2 kHz and had an equivalent rectangular bandwidth of 1 oct and a level of 70 dB sound pressure level. A three-alternative forced-choice procedure was combined with an adaptive procedure. With Rippled reference stimuli, the mean Ripple-density resolution limits were 8.9 Ripples/oct (phase-reversals test stimulus) or 7.7 Ripples/oct (constant-phase test stimulus). With nonRippled reference stimuli, the mean resolution limits were 26.1 Ripples/oct (phase-reversals test stimulus) or 22.2 Ripples/oct (constant-phase test stimulus). Different contributions of excitation-pattern and temporal-processing mechanisms are assumed for measurements with Rippled and nonRippled reference stimuli: The excitation-pattern mechanism is more effective for the discrimination of Rippled stimuli that differ in their Ripple-phase patterns, whereas the temporal-processing mechanism is more effective for the discrimination of Rippled and nonRippled stimuli.
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Discrimination of Rippled spectra: Contribution of excitation-pattern and temporal-processing mechanisms
The Journal of the Acoustical Society of America, 2019Co-Authors: Olga N. Milekhina, Dmitry I. Nechaev, Alexander Ya SupinAbstract:Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution specified in Ripples/oct little depended on center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled test and non-Rippled reference signals, the resolution specified in Ripple frequency spacing little depended on center frequency, as predicted by the temporal-processing model. It was concluded that contributions of the excitation-pattern and temporal-processing mechanism depend on the discrimination task. Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution spe...
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Discrimination of Rippled spectra at various frequencies: Contribution of excitation-pattern and temporal-processing mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled tests and nonRippled reference signals, the resolution specified in the Ripple frequency spacing depended very little on the center frequency, as predicted by the temporal-processing model. This study concluded that contributions of the excitation-pattern and temporal-processing mechanisms depend on the discrimination task.Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the ...
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Discrimination of Ripple depth in Rippled spectra: Contributions of spectral and temporal mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used to measure signal resolution in hearing-impaired listeners and cochlear implant users. Two mechanisms are believed to be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. Measurements were performed either by discrimination between the Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between the Rippled-spectrum test and a non-Rippled reference signal. For discrimination between the Rippled-spectrum test and reference signals, resolutions specified in Ripples/oct minimally depended on the center frequency, as predicted by the excitation-pattern model. For discrimination between the Rippled test and non-Rippled reference signals, the resolution specified by the Ripple frequency spacing minimally depended on the center frequency, as predicted by the temporal processing model. It was concluded that the contributions of the excitation-pattern and temporal processing mechanisms depended on the discrimination task.
Julia Jacobs - One of the best experts on this subject based on the ideXlab platform.
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High Frequency Oscillations in the Ripple Band (80–250 Hz) in Scalp EEG: Higher Density of Electrodes Allows for Better Localization of the Seizure Onset Zone
Brain Topography, 2018Co-Authors: N Kuhnke, J Schwind, Matthias Dumpelmann, M Mader, A. Schulze-bonhage, Julia JacobsAbstract:High frequency oscillations (HFO) are known as markers of epileptic areas in intracranial EEG and possibly scalp EEG. We compared distributions of HFO in the Ripple band (80–250 Hz) in intracranial and scalp EEG with either a conventional 10–20-montage (10–20-EEG) or a high density recording using 128 electrodes (HD-EEG). HFO were visually identified, in all intracranial EEG channels (80–500 Hz) and all channels of the 10–20-EEG (scalp EEG 80–250 Hz). For the HD-EEG, HFO were analyzed in regions of interest using areas with HFO as seen on the 10–20-EEG as well as areas in the clinically-defined seizure onset zone (SOZ). 13 patients were included in the study, of whom 12 showed HFO in the Ripple band. In 8 patients HD-EEG revealed additional regions of Ripples compared to the 10–20-EEG. With HD-EEG, areas of highest Ripple rates were corresponding between scalp and intracranial EEG in 7 patients (58%) and 8 (67%) patients showed highest Ripple rates over the SOZ. In contrast, with 10–20-EEG only 2 patients (17%) had corresponding areas of highest Ripple rates and only 3 patients (23%) showed highest Ripple rates over the SOZ. HD-EEG proved to be better to identify scalp HFO in the Ripple band compared to standard 10–20-EEG. Moreover, Ripples in 10–20-EEG seem to lead to false localization of epileptic areas. In contrast Ripples detected with HD-EEG were located over the seizure onset zone and maybe a promising tool to localize epileptic tissue in the future.
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high frequency oscillations in the Ripple band 80 250 hz in scalp eeg higher density of electrodes allows for better localization of the seizure onset zone
Brain Topography, 2018Co-Authors: N Kuhnke, J Schwind, Matthias Dumpelmann, M Mader, Andreas Schulzebonhage, Julia JacobsAbstract:High frequency oscillations (HFO) are known as markers of epileptic areas in intracranial EEG and possibly scalp EEG. We compared distributions of HFO in the Ripple band (80–250 Hz) in intracranial and scalp EEG with either a conventional 10–20-montage (10–20-EEG) or a high density recording using 128 electrodes (HD-EEG). HFO were visually identified, in all intracranial EEG channels (80–500 Hz) and all channels of the 10–20-EEG (scalp EEG 80–250 Hz). For the HD-EEG, HFO were analyzed in regions of interest using areas with HFO as seen on the 10–20-EEG as well as areas in the clinically-defined seizure onset zone (SOZ). 13 patients were included in the study, of whom 12 showed HFO in the Ripple band. In 8 patients HD-EEG revealed additional regions of Ripples compared to the 10–20-EEG. With HD-EEG, areas of highest Ripple rates were corresponding between scalp and intracranial EEG in 7 patients (58%) and 8 (67%) patients showed highest Ripple rates over the SOZ. In contrast, with 10–20-EEG only 2 patients (17%) had corresponding areas of highest Ripple rates and only 3 patients (23%) showed highest Ripple rates over the SOZ. HD-EEG proved to be better to identify scalp HFO in the Ripple band compared to standard 10–20-EEG. Moreover, Ripples in 10–20-EEG seem to lead to false localization of epileptic areas. In contrast Ripples detected with HD-EEG were located over the seizure onset zone and maybe a promising tool to localize epileptic tissue in the future.
N Kuhnke - One of the best experts on this subject based on the ideXlab platform.
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High Frequency Oscillations in the Ripple Band (80–250 Hz) in Scalp EEG: Higher Density of Electrodes Allows for Better Localization of the Seizure Onset Zone
Brain Topography, 2018Co-Authors: N Kuhnke, J Schwind, Matthias Dumpelmann, M Mader, A. Schulze-bonhage, Julia JacobsAbstract:High frequency oscillations (HFO) are known as markers of epileptic areas in intracranial EEG and possibly scalp EEG. We compared distributions of HFO in the Ripple band (80–250 Hz) in intracranial and scalp EEG with either a conventional 10–20-montage (10–20-EEG) or a high density recording using 128 electrodes (HD-EEG). HFO were visually identified, in all intracranial EEG channels (80–500 Hz) and all channels of the 10–20-EEG (scalp EEG 80–250 Hz). For the HD-EEG, HFO were analyzed in regions of interest using areas with HFO as seen on the 10–20-EEG as well as areas in the clinically-defined seizure onset zone (SOZ). 13 patients were included in the study, of whom 12 showed HFO in the Ripple band. In 8 patients HD-EEG revealed additional regions of Ripples compared to the 10–20-EEG. With HD-EEG, areas of highest Ripple rates were corresponding between scalp and intracranial EEG in 7 patients (58%) and 8 (67%) patients showed highest Ripple rates over the SOZ. In contrast, with 10–20-EEG only 2 patients (17%) had corresponding areas of highest Ripple rates and only 3 patients (23%) showed highest Ripple rates over the SOZ. HD-EEG proved to be better to identify scalp HFO in the Ripple band compared to standard 10–20-EEG. Moreover, Ripples in 10–20-EEG seem to lead to false localization of epileptic areas. In contrast Ripples detected with HD-EEG were located over the seizure onset zone and maybe a promising tool to localize epileptic tissue in the future.
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high frequency oscillations in the Ripple band 80 250 hz in scalp eeg higher density of electrodes allows for better localization of the seizure onset zone
Brain Topography, 2018Co-Authors: N Kuhnke, J Schwind, Matthias Dumpelmann, M Mader, Andreas Schulzebonhage, Julia JacobsAbstract:High frequency oscillations (HFO) are known as markers of epileptic areas in intracranial EEG and possibly scalp EEG. We compared distributions of HFO in the Ripple band (80–250 Hz) in intracranial and scalp EEG with either a conventional 10–20-montage (10–20-EEG) or a high density recording using 128 electrodes (HD-EEG). HFO were visually identified, in all intracranial EEG channels (80–500 Hz) and all channels of the 10–20-EEG (scalp EEG 80–250 Hz). For the HD-EEG, HFO were analyzed in regions of interest using areas with HFO as seen on the 10–20-EEG as well as areas in the clinically-defined seizure onset zone (SOZ). 13 patients were included in the study, of whom 12 showed HFO in the Ripple band. In 8 patients HD-EEG revealed additional regions of Ripples compared to the 10–20-EEG. With HD-EEG, areas of highest Ripple rates were corresponding between scalp and intracranial EEG in 7 patients (58%) and 8 (67%) patients showed highest Ripple rates over the SOZ. In contrast, with 10–20-EEG only 2 patients (17%) had corresponding areas of highest Ripple rates and only 3 patients (23%) showed highest Ripple rates over the SOZ. HD-EEG proved to be better to identify scalp HFO in the Ripple band compared to standard 10–20-EEG. Moreover, Ripples in 10–20-EEG seem to lead to false localization of epileptic areas. In contrast Ripples detected with HD-EEG were located over the seizure onset zone and maybe a promising tool to localize epileptic tissue in the future.
Dmitry I. Nechaev - One of the best experts on this subject based on the ideXlab platform.
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Rippled Depth Thresholds: Estimates Obtained by Discrimination From Rippled and NonRippled Reference Signals
Acta Acustica united with Acustica, 2019Co-Authors: Alexander Ya Supin, Olga N. Milekhina, Dmitry I. NechaevAbstract:The objective of the study was to better understand of contribution of excitation-pattern and temporal-processing mechanisms of frequency analysis to discrimination of complex-spectrum signals in various discrimination tasks. Using Rippled-spectrum signals, the Ripple depth thresholds were measured as functions of Ripple density under conditions of Rippled or non-Rippled reference signals. With Rippled reference signals, the Ripple depth thresholds were as low as 0.11 at low Ripple densities (2–3 cycles/oct) and rose to 1.0 at a Ripple density of 8.9 cycles/oct. For non-Rippled reference signals, Ripple depth thresholds were nearly the same as for Rippled reference signals at Ripple densities of up to 7 cycles/oct; at Ripple densities of 10 cycles/oct and higher, Ripple depth thresholds rose slowly and reached 1.0 at a Ripple density of 26 cycles/oct. The results hypothetically suggest contributions of the excitation-pattern processing and temporal-processing mechanisms of frequency analysis to discrimination of Rippled signals. The excitation-pattern mechanism featured low depth thresholds at low Ripple densities but could not function at Ripple densities above 10 cycles/oct. The temporal-processing mechanism manifested at higher Ripple densities and non-Rippled reference stimuli.
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Estimates of Ripple-Density Resolution Based on the Discrimination From Rippled and NonRippled Reference Signals.
Trends in hearing, 2019Co-Authors: Dmitry I. Nechaev, Olga N. Milekhina, Alexander Ya SupinAbstract:: Rippled-spectrum stimuli are used to evaluate the resolution of the spectro-temporal structure of sounds. Measurements of spectrum-pattern resolution imply the discrimination between the test and reference stimuli. Therefore, estimates of Rippled-pattern resolution could depend on both the test stimulus and the reference stimulus type. In this study, the Ripple-density resolution was measured using combinations of two test stimuli and two reference stimuli. The test stimuli were Rippled-spectrum signals with constant phase or Rippled-spectrum signals with Ripple-phase reversals. The reference stimuli were Rippled-spectrum signals with opposite Ripple phase to the test or nonRippled signals. The spectra were centered at 2 kHz and had an equivalent rectangular bandwidth of 1 oct and a level of 70 dB sound pressure level. A three-alternative forced-choice procedure was combined with an adaptive procedure. With Rippled reference stimuli, the mean Ripple-density resolution limits were 8.9 Ripples/oct (phase-reversals test stimulus) or 7.7 Ripples/oct (constant-phase test stimulus). With nonRippled reference stimuli, the mean resolution limits were 26.1 Ripples/oct (phase-reversals test stimulus) or 22.2 Ripples/oct (constant-phase test stimulus). Different contributions of excitation-pattern and temporal-processing mechanisms are assumed for measurements with Rippled and nonRippled reference stimuli: The excitation-pattern mechanism is more effective for the discrimination of Rippled stimuli that differ in their Ripple-phase patterns, whereas the temporal-processing mechanism is more effective for the discrimination of Rippled and nonRippled stimuli.
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Discrimination of Rippled spectra: Contribution of excitation-pattern and temporal-processing mechanisms
The Journal of the Acoustical Society of America, 2019Co-Authors: Olga N. Milekhina, Dmitry I. Nechaev, Alexander Ya SupinAbstract:Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution specified in Ripples/oct little depended on center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled test and non-Rippled reference signals, the resolution specified in Ripple frequency spacing little depended on center frequency, as predicted by the temporal-processing model. It was concluded that contributions of the excitation-pattern and temporal-processing mechanism depend on the discrimination task. Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution spe...
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Discrimination of Rippled spectra at various frequencies: Contribution of excitation-pattern and temporal-processing mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled tests and nonRippled reference signals, the resolution specified in the Ripple frequency spacing depended very little on the center frequency, as predicted by the temporal-processing model. This study concluded that contributions of the excitation-pattern and temporal-processing mechanisms depend on the discrimination task.Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the ...
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Discrimination of Ripple depth in Rippled spectra: Contributions of spectral and temporal mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used to measure signal resolution in hearing-impaired listeners and cochlear implant users. Two mechanisms are believed to be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. Measurements were performed either by discrimination between the Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between the Rippled-spectrum test and a non-Rippled reference signal. For discrimination between the Rippled-spectrum test and reference signals, resolutions specified in Ripples/oct minimally depended on the center frequency, as predicted by the excitation-pattern model. For discrimination between the Rippled test and non-Rippled reference signals, the resolution specified by the Ripple frequency spacing minimally depended on the center frequency, as predicted by the temporal processing model. It was concluded that the contributions of the excitation-pattern and temporal processing mechanisms depended on the discrimination task.
Olga N. Milekhina - One of the best experts on this subject based on the ideXlab platform.
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Rippled Depth Thresholds: Estimates Obtained by Discrimination From Rippled and NonRippled Reference Signals
Acta Acustica united with Acustica, 2019Co-Authors: Alexander Ya Supin, Olga N. Milekhina, Dmitry I. NechaevAbstract:The objective of the study was to better understand of contribution of excitation-pattern and temporal-processing mechanisms of frequency analysis to discrimination of complex-spectrum signals in various discrimination tasks. Using Rippled-spectrum signals, the Ripple depth thresholds were measured as functions of Ripple density under conditions of Rippled or non-Rippled reference signals. With Rippled reference signals, the Ripple depth thresholds were as low as 0.11 at low Ripple densities (2–3 cycles/oct) and rose to 1.0 at a Ripple density of 8.9 cycles/oct. For non-Rippled reference signals, Ripple depth thresholds were nearly the same as for Rippled reference signals at Ripple densities of up to 7 cycles/oct; at Ripple densities of 10 cycles/oct and higher, Ripple depth thresholds rose slowly and reached 1.0 at a Ripple density of 26 cycles/oct. The results hypothetically suggest contributions of the excitation-pattern processing and temporal-processing mechanisms of frequency analysis to discrimination of Rippled signals. The excitation-pattern mechanism featured low depth thresholds at low Ripple densities but could not function at Ripple densities above 10 cycles/oct. The temporal-processing mechanism manifested at higher Ripple densities and non-Rippled reference stimuli.
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Estimates of Ripple-Density Resolution Based on the Discrimination From Rippled and NonRippled Reference Signals.
Trends in hearing, 2019Co-Authors: Dmitry I. Nechaev, Olga N. Milekhina, Alexander Ya SupinAbstract:: Rippled-spectrum stimuli are used to evaluate the resolution of the spectro-temporal structure of sounds. Measurements of spectrum-pattern resolution imply the discrimination between the test and reference stimuli. Therefore, estimates of Rippled-pattern resolution could depend on both the test stimulus and the reference stimulus type. In this study, the Ripple-density resolution was measured using combinations of two test stimuli and two reference stimuli. The test stimuli were Rippled-spectrum signals with constant phase or Rippled-spectrum signals with Ripple-phase reversals. The reference stimuli were Rippled-spectrum signals with opposite Ripple phase to the test or nonRippled signals. The spectra were centered at 2 kHz and had an equivalent rectangular bandwidth of 1 oct and a level of 70 dB sound pressure level. A three-alternative forced-choice procedure was combined with an adaptive procedure. With Rippled reference stimuli, the mean Ripple-density resolution limits were 8.9 Ripples/oct (phase-reversals test stimulus) or 7.7 Ripples/oct (constant-phase test stimulus). With nonRippled reference stimuli, the mean resolution limits were 26.1 Ripples/oct (phase-reversals test stimulus) or 22.2 Ripples/oct (constant-phase test stimulus). Different contributions of excitation-pattern and temporal-processing mechanisms are assumed for measurements with Rippled and nonRippled reference stimuli: The excitation-pattern mechanism is more effective for the discrimination of Rippled stimuli that differ in their Ripple-phase patterns, whereas the temporal-processing mechanism is more effective for the discrimination of Rippled and nonRippled stimuli.
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Discrimination of Rippled spectra: Contribution of excitation-pattern and temporal-processing mechanisms
The Journal of the Acoustical Society of America, 2019Co-Authors: Olga N. Milekhina, Dmitry I. Nechaev, Alexander Ya SupinAbstract:Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution specified in Ripples/oct little depended on center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled test and non-Rippled reference signals, the resolution specified in Ripple frequency spacing little depended on center frequency, as predicted by the temporal-processing model. It was concluded that contributions of the excitation-pattern and temporal-processing mechanism depend on the discrimination task. Rippled-spectrum signals are used for measurements of signal resolution in hearing-impaired listeners and cochlear-implant users. Two mechanisms may be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). Contributions of the mechanisms can be assessed by comparison of resolutions of band-limited Rippled spectra with different center frequencies, because the ratio of rippe spacing to Ripple density is frequency-proportional. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. The measurements were performed either by discrimination between Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and non-Rippled reference signal. For discrimination between Rippled-spectrum test and reference signals, resolution spe...
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Discrimination of Rippled spectra at various frequencies: Contribution of excitation-pattern and temporal-processing mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the center frequency, as predicted by the excitation-pattern model. For discrimination between Rippled tests and nonRippled reference signals, the resolution specified in the Ripple frequency spacing depended very little on the center frequency, as predicted by the temporal-processing model. This study concluded that contributions of the excitation-pattern and temporal-processing mechanisms depend on the discrimination task.Rippled-spectrum signals are used for signal-resolution measurements in hearing-impaired listeners and cochlear implant users. Two mechanisms are presumably responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple-density resolution (Ripples/oct). The temporal-processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies ranging from 0.5 to 4 kHz. The measurements were performed either by discrimination between a Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between a Rippled-spectrum test and a nonRippled reference signal. For discrimination between Rippled-spectrum tests and reference signals, the resolution specified in Ripples/oct depended very little on the ...
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Discrimination of Ripple depth in Rippled spectra: Contributions of spectral and temporal mechanisms
178th Meeting of the Acoustical Society of America, 2019Co-Authors: Alexander Ya Supin, Dmitry I. Nechaev, Olga N. Milekhina, Evgenia V. SysuevaAbstract:Rippled-spectrum signals are used to measure signal resolution in hearing-impaired listeners and cochlear implant users. Two mechanisms are believed to be responsible for Rippled-spectrum resolution. The excitation-pattern mechanism determines the Ripple density resolution (Ripples/oct). The temporal processing mechanism determines the Ripple frequency spacing limit (kHz). The contributions of these two mechanisms can be assessed by comparing the resolutions of band-limited Rippled spectra with different center frequencies. Ripple-density resolutions of half-octave Rippled spectra were measured at center frequencies from 0.5 to 4 kHz. Measurements were performed either by discrimination between the Rippled-spectrum test and reference signals differing by Ripple phases or by discrimination between the Rippled-spectrum test and a non-Rippled reference signal. For discrimination between the Rippled-spectrum test and reference signals, resolutions specified in Ripples/oct minimally depended on the center frequency, as predicted by the excitation-pattern model. For discrimination between the Rippled test and non-Rippled reference signals, the resolution specified by the Ripple frequency spacing minimally depended on the center frequency, as predicted by the temporal processing model. It was concluded that the contributions of the excitation-pattern and temporal processing mechanisms depended on the discrimination task.
