Related Experiment Video
Updated: Aug 15, 2026
06:34
Infant Auditory Processing and Event-related Brain Oscillations
Published on: July 1, 2015
First-order and second-order spectral 'motion' mechanisms in the human auditory system
Wendy E Huddleston1, Edgar A DeYoe
1Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
Perception
|December 4, 2003
Summary
Researchers explored auditory motion perception, finding that
Area of Science:
- Auditory perception
- Psychoacoustics
- Sensory processing
Background:
- Visual motion perception involves energy displacement across photoreceptors.
- Auditory spectral motion (pitch change) is analogous to mechanical energy displacement along cochlear hair cells.
- Vision has second-order motion stimuli independent of direct energy displacement.
Purpose of the Study:
- Investigate if analogous second-order motion stimuli exist in audition.
- Compare the perception of auditory second-order motion to first-order spectral motion.
Main Methods:
- Used psychophysical methods to test auditory motion perception.
- Employed first-order stimuli: frequency sweeps of non-harmonic tones (297-12123 Hz).
- Developed second-order stimuli: random tone state transitions (ON/OFF) creating sweeps without net energy displacement.
Main Results:
- Subjects identified sweep direction for both first-order and second-order auditory stimuli at slow speeds.
- Accuracy for second-order stimuli decreased as sweep speed increased.
- Performance on second-order stimuli mirrored some visual second-order motion characteristics.
Conclusions:
- Second-order auditory motion stimuli exist and are perceivable.
- Auditory and visual systems may share stronger processing parallels than previously understood.
- Further research can explore the neural mechanisms underlying these cross-modal similarities.
Related Concept Videos
01:31Hearing
When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
01:01Perception of Sound Waves
The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
01:15Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
01:21Perceiving Loudness, Pitch, and Location
The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...