Related Experiment Video
Updated: Jun 4, 2026
11:15
fMRI Mapping of Brain Activity Associated with the Vocal Production of Consonant and Dissonant Intervals
Published on: May 23, 2017
Tracking vocal pitch through noise: neural correlates in nonprimary auditory cortex
Lars Riecke1, Anke Walter, Bettina Sorger
1Department of Cognitive Neuroscience, Maastricht University, 6200 MD Maastricht, The Netherlands. L.Riecke@MaastrichtUniversity.nl
Summary
Auditory continuity illusions, where sounds seem continuous despite interruptions, involve reduced brain activity in specific auditory cortex regions. This mechanism helps us perceive stable sounds even with louder masking noises.
Area of Science:
- Neuroscience
- Auditory Perception
- Psychoacoustics
Background:
- Natural sounds are perceived as stable despite intervening louder noises.
- Auditory continuity illusions, like hearing an interrupted voice as continuous, occur when masking noise replaces parts of a sound.
- Previous studies linked continuity illusions of simple tones to reduced activity in the primary auditory cortex (PAC).
Purpose of the Study:
- To investigate if continuity illusions for complex sounds like vowels also involve reduced neural activity.
- To determine if the suppressive mechanism observed for simple tones extends to more naturalistic auditory stimuli.
- To explore the neural correlates of auditory continuity illusions in complex sound perception.
Main Methods:
- Human participants underwent psychophysical testing and functional magnetic resonance imaging (fMRI).
- Simultaneously measured continuity ratings and blood oxygenation level-dependent (BOLD) activity.
- Stimuli consisted of vowels partially replaced by masking noise.
Main Results:
- Increased reports of vowel continuity illusions correlated with decreased activity in auditory cortex regions.
- This neural suppression, unlike that for simple tones in PAC, was localized to the right anterolateral Heschl's gyrus (non-PAC).
- Percepts of veridical discontinuity showed stronger auditory cortex activity compared to illusory continuity.
Conclusions:
- Continuity illusions for complex sounds like vowels arise from a common suppressive mechanism within the auditory cortex.
- This mechanism operates at different levels of sound representation, not solely in the primary auditory cortex.
- The findings suggest a widespread neural strategy for maintaining auditory stability amidst acoustic interference.
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.
01:21Perceiving 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...
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...
01:17Auditory Perception
The auditory system is essential for sound perception, utilizing various critical structures. When sound waves enter the outer ear, they travel through the ear canal and cause the eardrum to vibrate. These vibrations are then transmitted to the middle ear, where three tiny bones – the malleus, incus, and stapes – amplify the sound. This amplification is crucial, as it ensures that the sound vibrations are strong enough to be conveyed to the inner ear. These vibrations then reach the cochlea, a...
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.
01:29Non-Verbal Cues
Non-verbal communication extends beyond gestures and facial expressions to include vocal elements known as paralanguage. Paralanguage consists of non-verbal vocal cues such as pitch, loudness, speech rate, pauses, and non-verbal vocalizations like laughter, sighs, and moans. These elements not only accompany speech but also provide critical emotional and contextual information.The Role of Paralanguage in CommunicationParalanguage adds depth to spoken language by conveying emotions and...