LIN175-Midterm2-Prep

Linguistics 175 - Quiz 2

1. Neuroimaging Techniques

• Spatial vs. Temporal Resolution
  • Know the different “sizes” of spatial resolution:
    • Cortical regions - Larger, more corresponding to lobes
    • Brodmann’s areas - Smaller, areas 44 & 45 correspond to broca’s area.
    • Single cell recording - Record as small as neurons.
• Comparison of Techniques:
  • MRI
    • Detects blood flow changes
    • Pros: Spatial resolution, non-invasive
    • Cons: Temporal resolution
  • PET
    • Tracks movement of radioactive tracer
    • Pros: Good spatial resolution
    • Cons: Invasive (tracer) and lower temporal
  • MEG
    • Measures magnetic fields produced by brain
    • Pros: Temporal resolution, non invasive
    • Cons: Not great spatial resolution, susceptible to movement
  • ERP (Event-Related Potentials)
    • Electrical activity on the scalp
    • Pros: Temporal resolution, non invasive, cheap
    • Cons: Bad spatial resolution, noisy
  • NIRS (Near-Infrared Spectroscopy)
    • Measures change in blood oxygenation using near-infrared light
    • Pros: Inexpensive, portable, non invasive
    • Lower spatial and temporal resolution
  • ECOG
    • Electrodes placed on the brain
    • Pros: High spatial and temporal resolution
    • Cons: Very invasive
  • Neuropsychological testing/Lesion studies
    • Examines cognitive capabilities using tasks
    • Pros: Some of our biggest insights
    • Cons: Not as scientific or controlled
• Spatial:
  • MRI > MEG > PET > NIRS > ERP
• Temporal:
  • MEG=ERP > fMRI > PET > NIRS
• Populations:
  • fMRI can’t be used for people with metal implants very well
  • Claustrophobics no scanners

2. Brain Damage & Neuropsychological Testing

• Double Dissociation
• Neuropsychological testing,
• Potential impacts of tumor resection on language function
  • Post-surgical neuropsychological testing
• Aphasia vs. Apraxia

3. Brain Stimulation & Cognitive Recovery

• Transcranial Direct Current Stimulation (tDCS)
• Transcranial Magnetic Stimulation (TMS)

4. Cognitive Neuroscience Methods

• Subtractive Logic in MRI
• Experimental Design Considerations
  • What factors are important in deciding whether the results of a study support your theory?
• Purpose of peer-review journals

5. Classical Models of Language Processing

• Wernicke-Lichtheim-Geschwind Model:

• Ventral and Dorsal Pathways - Milner and Goodale (1995)

  • Ventral Stream - What.
    • “The transformations carried out in the ventral stream permit the formation of perceptual and cognitive representations which embody the enduring characteristics of objects and their significance”
  • Dorsal Stream - How/Where
    • “concerned only with the observer’s actions within the visual world. The transformations carried out in the dorsal stream, mediate the control of goal-directed actions”

• What and Where in Language:
  

  • Ventral Pathway
    • Lexical Conceptual processing (Wernicke’s)
  • Dorsal Pathway
    • Sensori-motor/articulation (to Broca’s)
    • Doing things with language

• Hickok & Poeppel Model:
  

• Purple is the ventral stream

  • Maps the sound structures of words onto the corresponding semantic representations
  • Contributes to forming the integrated meanings of complex utterances like phrases and sentences

• Dual stream vs single stream models

• Review homework 3

Lemma Model:

• Two stages of lexical selection
  • Lexical selection:
    • Conceptual focusing perspective-taking
    • Lexical concept
    • Lemma selection
  • Lemma
    |
    \/
• Three stages of form encoding
  • Form encoding:
    • Retrieving morphemic phonological codes
    • Phonological codes
    • Prosodification syllabification
    • Phonological word
    • Phonetic encoding
  • Articulatory score

6. Visual & Auditory Processing

• Visual Field Processing:
  • Left visual field → right hemisphere
  • Right visual field → left hemisphere