Test 3: Lateralization, Language, and Split Brain Flashcards
active conciousness
the state of being aware of your thoughts and behaviors
what do human beings use to make their declarative knowledge accessible?
language
commisures
fiber pathways that connect the two hemispheres
corpus collosum
largest commissure in the brain
allows cross talk between the hemispheres
severed to control epilepsy
What transfers learned information from one hemisphere to the next
corpus callosum
what happens to function when the corpus callosum is severed
each hemisphere functions independently
How does commisourotomy help epileptics
It reduces convulsive behavior
they may never have a major convulsion again
Michael Gazzaniga
developed procedures to test split-brain patients
How do the hemispheres function for split brain patients
left hemisphere can tell what the person has seen, the right hemisphere can show it
What happens when you show a picture to a split brain persons right visual field?
It is “seen” by their left brain
Left hemisphere can tell you what it was
right hand can show you but the left hand cannot
What happens when a picture is presented to the left visual field of a split brain patient
Seen by the right hemisphere
They will say they don’t know what they saw
Left hand can show what it is but the right hand cannot
Results of chimeric figures task - composite face study
half of a face is shown to each hemisphere
each side will report having seen a whole face
Z lens
Named for Erin Zadel
device for showing visual input to split brain patients one hemisphere at a time
contact lens that is opaque on one side so that visual input only goes to one hemisphere
What did the z-lens spoken experiments show?
the right hemisphere language abilities are around that of a 10 year old for single words
Differences between hemisphere
Not absolute; minimal differences
right does have some language ability
In general: left hemisphere specialization
language and speech
analytical and sequential
In general: right hemisphere specialization
visual and spatial processing
processing info simultaneously as a whole
left hemisphere controls speech and language in _____ of right handers and ______ of left
95%
70%
2 important brain areas for speech and language
broca’s
wernicke’s
Broca’s area
Where
What happens when damaged
frontal lobe
Broca’s aphasia - can understand but has difficulty producing sounds of speech
Wernicke’s area
Where
What happens when damaged
temporal lobe
Wernicke’s aphasia - difficulty comprehending, speech is normal but with no meaning
circulate fasciculins
connects Broca’s and Wernick’s area
arcuate fasciculus
form and meaning that is produced in Wernicke’s area goes by way of this to Broca’s
What happens when language is read
Words are processed through different but similar pathways
fibers from primary visual cortex project to the angular gyrus in the temporal lobe
input is matched with sounds of words when spoken
auditory form then processed by wernicke’s area as if it were heard
