Language and Imaging

Language and Imaging

1. What is language

   • Words (spoken, written, signed) conveying object, relationship, ideas
     • Mapping of meaning arbitrary
     • This bit's not unique
       • Bee dance
       • Vervet monkey
   • Rule-based
   • communication
   • symbolic

2. Who's learned it?

   • Washoe
     • Child-like language
   • Nim
     • Raised as kid
   • Kanzi
     • Keyboard and spoken
       • Learned from mom, authentic

3. Vocal apparatus

   • Phonation
     • Vibrations
       • larynx
       • Vocal cords
       • pharynx
       • mouth
       • Cavities
   • Articulation
     • tuning of vibrations
       • mandible
       • soft palate
       • tongue
       • lips

4. Language in the brain

   • equipotentiality
     • all capable of everything
       • maybe not at all times
         • but there's flexibility
     • damage is about how much not where
   • phrenology
     • places have roles
     • i.e. skull
     • Bouillaud
       • frontal lobe
         • speech deficits
   • aphasia
     • broca
       • content words
         • second and third convolutions of the inferior frontal gyrus (IFG)
       • swear
       • tan
     • Wernicke's
       • lots of babbling
         • limited meaning
       • two-componant model
         • talked about anterior-motor, posterior-sensory
         • connected by arcuate fasciculus
           • conduction aphasia
             • can talk, can understand
             • cannot repeat
         • limitations
           • only verbal
           • reading/writing not accounted for
           • cannot predict outcomes in children

5. Compensation

   • Children with insults indistinguishable (L/R or controls)
   • Interhemispheric
     • compensate on right
   • Intrahemispheric
     • Compensate somewhere else in left
   • subtle difference in free speech

6. Assessing laterality

   • Invasive
     • Intracarotid sodium amobartial (IAP)/Wada
       • Barbiturate
       • internal carotid
         • perfuse laterally
         • temporary disruption
           • Bilateral?
             • Disruption with both
             • Disruption with neither
     • Electrocortical stimulation/ extraoperative stimulation mapping (ESM)
       • awake craniotomy
         • implant electrode
           • administer current (disrupts)
             • increased flexibility
               • can test lower fuctioning
   • Noninvasive
     • fMRI
       • Block
       • event-related
       • Presurgical planning
         • motor, somato, visual, auditory
         • memory encoding and recall
         • seizure-generating tissue
         • language
           • receptive (listening)
           • expressive (verb gen)
     • magnetoencephalography
       • MEG is for everyone!
         • word recognition task