7 - Speaking And Its Sensory Consequences Flashcards
What does the forward model framework state?
It states that a copy of speech motor commands (efference copy) allows for the prediction of sensory consequences of motor commands.
Why is the prediction of sensory consequences of motor commands important?
To correct potential speech production errors
To distinguish self-generated speech input from external speech
What happens if there is a match between predicted and actual speech feedback?
The neural activity is locally canceled or inhibited. A match decreases the neural activity in auditory areas activated by verbal feedback.
What is evidence for the fact that sensory predictions of speech are very specific?
The activity in early auditory cortical region varied proportional to the parametric level of the noise mask during overt speech. Even small speech production errors are highlighted.
Where does the suppression effect take place?
Superior temporal gyrus (STG)
What is motor-induced suppression?
This reflects the subtraction of predicted feedback for observed feedback.
How do we know sure the content of the efference copy is the prototype?
The closer to the prototype, the more suppression is seen. Therefore the convent of the efference copy should be the prototype.
Explain why the left hemisphere shows more modulation of speech-induced suppression
Because the left hemisphere is more sensitive to speech variability. It is more speech related than the right hemisphere which is more activated by general audio.
Why is external feedback important?
Learn relationship between motor commands and their sensory consequences in the first place (learn internal model)
Update internal model in case of persistent mismatches (errors) between predicted and measured stated owing to system drift or shifting sensory-motor conditions (motor fatigue)
Detect and correct for sudden perturbations
