WK4 L7: Speech Perception I

• Why is it difficult to discuss speech perception without mentioning speech production?


  Because they are closely linked in the process of communication
• What is one reason why speech perception is challenging?

  Variability in speech sounds
• How can F1 and F2 vary for a given vowel?

  They can differ based on individual speaker characteristics and vocal tract size
• What does coarticulation refer to in speech production?

  The influence of surrounding sounds on speech sounds
• What is the effect of coarticulation on speech sounds?

  It can cause the same set of muscle configurations to be perceived as different sounds
• What are the two types of coarticulation?

  • Anticipatory coarticulation: articulating an upcoming sound during the preceding sound
  • Carryover coarticulation: sounds influenced by preceding sounds
• How does anticipatory coarticulation manifest in speech?

  By starting to articulate a sound before it is fully pronounced
• How does the articulation of [k] differ in "ski" compared to "skunk"?

  The place of articulation changes due to surrounding sounds
• What factors contribute to variation in speech production?

  Individual differences, accent/dialect differences, and phonemic contexts
• What is the purpose of the DIVA model in speech production?

  • To simulate how babies learn to speak
  • To improve text-to-speech systems
  • To understand human vocal tract control
• What is the Motor Theory of Speech Perception?

  A theory suggesting that each phoneme has an invariant set of motor commands associated with it
• What does the dual-route model of speech processing propose?

  It proposes two processing routes: auditory-conceptual and auditory-motor
• What are the components of the dual-route model of speech processing?

  • Ventral stream: processes speech signals for comprehension
  • Dorsal stream: processes acoustic information for speech production
• Which hemisphere is primarily responsible for the dorsal stream in speech processing?

  The left hemisphere
• What is the role of motor activation during speech perception according to the dual-route model?

  It implies that motor activation occurs during the perception of speech sounds
• What is Transcranial Magnetic Stimulation (TMS) used for in speech research?

  • To induce a current in specific areas of the cortex
  • To measure motor evoked potentials (MEPs)
  • To study the excitability of the motor system during speech production
• What was the focus of the TMS study by Watkins et al. (2003)?

  To measure changes in the excitability of the motor system underlying speech production
• What were the results regarding motor evoked potentials (MEPs) in the TMS study?

  MEPs were larger when the left hemisphere motor face area was stimulated
• What type of potentials can excitatory TMS induce?

  Motor Evoked Potentials (MEPs)
• What was the main focus of the TMS study by Watkins et al. (2003)?

  To investigate changes in the excitability of the motor system underlying speech production
• What was the dependent measure in the Watkins et al. (2003) study?

  The size of the MEP in the lip muscles
• How does excitatory TMS affect the primary motor face area?

  It induces a current in the brain responsible for face movements
• What was the result of stimulating the left hemisphere motor face area compared to the right in the study?

  MEPs recorded from the lip were larger when the left hemisphere was stimulated

  
• What happens to MEPs during speech and lip conditions compared to the control condition?

  MEPs are larger for speech and lip conditions compared to the control condition

  
• What does the activation of the motor system during speech perception suggest according to simulation-based theories?

  It suggests that we perceive by internally simulating the movements of the articulators
• What is the role of simulation in speech perception?

  It provides immediate information about the ongoing course of observed movement
• What is the implication of enhancing motor activation during speech perception?

  It may enhance perception, suggesting a causal relationship
• What does the Motor Theory of Speech Perception propose?

  It proposes that activation of the motor system is necessary for speech perception
• What did the adaptation study by Adank et al. (2010) investigate?

  Whether people understand a novel accent better if they try to imitate it
• What was the main finding of the adaptation study regarding accent training?

  Only imitation training conditions improved understanding more than the baseline
• How does exposure to an accent affect understanding according to the study?

  It improves understanding of that accent
• What is the relationship between speech production and speech perception?

  They are closely linked, as learning to speak involves reproducing sounds heard
• What are the key findings from the TMS study by Watkins et al. (2003)?

  • MEPs are larger when the left hemisphere motor face area is stimulated.
  • MEPs are larger for speech and lip conditions compared to control conditions.
  • Activation occurs in speech-relevant muscles when hearing or seeing speech.

  
• What are the implications of the findings from the adaptation study by Adank et al. (2010)?

  • Imitation training enhances understanding of novel accents.
  • Passive exposure does not improve understanding as effectively.
  • Speech perception adapts with exposure and practice.
• What are the proposed functions of motor activation during speech perception?

  • Automatic mirroring/imitation.
  • Perceptual fill-in, especially in noisy environments.
  • Recognition through simulation of sounds.
• What is the significance of sensory-motor integration in speech perception?

  • It plays a key role in learning to speak.
  • It aids in monitoring and adapting to speech changes.
  • It links perceptual and motor representations for better understanding.
• What are the steps involved in the adaptation process to accents?

  • Listeners adjust expectations about pronunciation.
  • Perceptual adaptations can lead to motor adaptations.
  • Imitation may facilitate sensory-motor integration.