Functional modelling of interaural time difference discrimination in acoustical and electrical hearing
Andreas Prokopiou1, Arturo Moncada-Torres1, Jan Wouters1
1University of Leuven, Department of Neurosciences, ExpORL. Herestraat 49, Bus 721, 3000 Leuven, Belgium.
Journal of Neural Engineering
|May 3, 2017
Summary
This study introduces a model to predict just noticeable differences (JNDs) in interaural time difference (ITD) discrimination for normal hearing and cochlear implant users. The model accurately predicts ITD sensitivity for various sounds, aiding in sound encoding strategy research.
Area of Science:
- Auditory Neuroscience
- Signal Processing
- Psychoacoustics
Background:
- Interaural time differences (ITDs) are crucial for sound localization.
- Predicting just noticeable differences (JNDs) in ITD discrimination is vital for understanding auditory perception, especially with cochlear implants.
Purpose of the Study:
- To develop and validate a computational model for predicting JNDs in ITD discrimination.
- To assess the model's performance for both normal hearing and electric hearing via cochlear implants.
- To provide a tool for investigating the impact of stimulus modifications on ITD sensitivity.
Main Methods:
- Combined peripheral models of acoustic and electric stimulation.
- Incorporated a novel JND estimation stage using a shuffled cross correlogram and binary classifier.
- Evaluated the model using a large behavioral dataset.
Main Results:
- The model accurately predicts behavioral observations for unmodulated stimuli (e.g., pure tones, electric pulse trains).
- Model predictions align with observed trends for modulated stimuli below 30 Hz modulation frequency.
- For higher modulation frequencies, the model shows good trend prediction but estimates higher ITD sensitivity.
Conclusions:
- The developed model effectively predicts ITD discrimination JNDs across different hearing conditions.
- This model serves as a valuable tool for exploring sound encoding strategies and stimulus waveform effects in cochlear implant research.
Related Concept Videos
01:10Interference: Path Lengths
2.3K
Consider two sources of sound, that may or may not be in phase, emitting waves at a single frequency, and consider the frequencies to be the same.
Two special sources may be considered when they are in phase. This can be easily achieved by feeding the two sources from the same source. An example would be synchronizing the two speakers by feeding them with the same source, such as the sound waves produced by a tuning fork. This setup ensures that the two sources have the same frequency and are...
Two special sources may be considered when they are in phase. This can be easily achieved by feeding the two sources from the same source. An example would be synchronizing the two speakers by feeding them with the same source, such as the sound waves produced by a tuning fork. This setup ensures that the two sources have the same frequency and are...
2.3K
01:06Echo
1.1K
The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More than this, and they are perceived as separate sources.
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...
1.1K
00:53Sound Waves: Interference
5.0K
Sound waves can be modeled either as longitudinal waves, wherein the molecules of the medium oscillate around an equilibrium position, or as pressure waves. When two identical waves from the same source superimpose on each other, the combination of two crests or two troughs results in amplitude reinforcement known as constructive interference. If two identical waves, that are initially in phase, become out of phase because of different path lengths, the combination of crests with troughs...
5.0K
01:24Properties of Fourier Transform II
830
The Fourier Transform (FT) is an essential mathematical tool in signal processing, transforming a time-domain signal into its frequency-domain representation. This transformation elucidates the relationship between time and frequency domains through several properties, each revealing unique aspects of signal behavior.
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
830
00:53Sound Intensity Level
5.0K
Humans perceive sound by hearing. The human ear helps sound waves reach the brain, which then interprets the waves and creates the perception of hearing. The loudness of the environment in which a person is located determines whether they can distinguish between different sound sources.
The human ear can perceive an extensive range of sound intensity, necessitating the use of the logarithmic scale to define a physical quantity—the intensity level. It is a ratio of two intensities and...
The human ear can perceive an extensive range of sound intensity, necessitating the use of the logarithmic scale to define a physical quantity—the intensity level. It is a ratio of two intensities and...
5.0K