Related Experiment Video
Updated: Jun 27, 2026
06:34
Infant Auditory Processing and Event-related Brain Oscillations
Published on: July 1, 2015
The cortical dynamics of intelligible speech
Alexander P Leff1, Thomas M Schofield, Klass E Stephan
1Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom. a.leff@fil.ion.ucl.ac.uk
Summary
The human brain processes speech meaning through a forward system, connecting the posterior superior temporal sulcus to anterior regions. This network shows increased connectivity when listening to intelligible speech.
Area of Science:
- Neuroscience
- Cognitive Science
- Psycholinguistics
Background:
- Understanding speech comprehension is crucial for neuroscience.
- The brain's semantic processing network is not fully understood.
- Directed interactions among speech-processing regions require systematic analysis.
Purpose of the Study:
- To investigate directed interactions among key brain regions during speech comprehension.
- To identify the network model that best explains brain activity during semantic processing of speech.
- To analyze experimentally induced changes in neural coupling.
Main Methods:
- Dynamic Causal Modeling (DCM) of functional magnetic resonance imaging (fMRI) data.
- Bayesian Model Selection (BMS) to compare 216 different network models.
- Analysis of neural coupling changes in response to intelligible speech.
Main Results:
- A "forward" model best explained the data, with auditory input to the posterior superior temporal sulcus (pSTS).
- Forward connections from pSTS to anterior STS (aSTS) and pars orbitalis (POrb) significantly increased during intelligible speech.
- Connectivity strength increased by 76% from pSTS to aSTS and 150% from pSTS to POrb.
Conclusions:
- The findings reveal a specific directed network for speech comprehension.
- Task-related, directional effects in neural coupling can be modeled.
- This study advances our understanding of the neural basis of semantic speech processing.
Related Concept Videos
01:10Higher Mental Functions of the Brain: Language
Language is a system of communication that allows the expression of thoughts, ideas, and feelings. The brain processes language in both hemispheres.
Language formation and comprehension take place in the dominant hemisphere. The dominant hemisphere is responsible for understanding the meaning of spoken, written, or sign language, as well as the ability to communicate. For most people, the left hemisphere is the dominant one. The right hemisphere, then, gives tone and emotional context to the...
Language formation and comprehension take place in the dominant hemisphere. The dominant hemisphere is responsible for understanding the meaning of spoken, written, or sign language, as well as the ability to communicate. For most people, the left hemisphere is the dominant one. The right hemisphere, then, gives tone and emotional context to the...
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...
01:31Hearing
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.
01:14Motor and Sensory Areas of the Cortex
The cerebral cortex, the brain's outermost layer, is pivotal in processing complex cognitive tasks, emotions, and various sensory inputs and executing voluntary motor activities. This intricate structure is divided into three primary functional areas: the motor areas, sensory areas, and association areas.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
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...
01:05Cerebral Hemispheres
The human brain, a complex organ, is functionally divided into two cerebral hemispheres—left and right. These hemispheres are interconnected by a structure of paramount importance, the corpus callosum. This substantial bundle of neural fibers is not just a bridge between the hemispheres but a crucial element for the brain's comprehensive functioning. It enables efficient communication between the two hemispheres, allowing each side of the brain to control and receive sensory and motor...