Nov. 2, 2023: week 8 notes
neurolinguistics (a branch of neuroscience) that has the goal of understanding how language is represented and processed in the brain
aristole thought that the primary function of the brain was to cool the blood
Aphasia
a broad term to describe numerous syndromes of communicative impairment
impairment of reading ability is called acquired dyslexia (or acquired alexia)
impairment of writing ability is called acquired dysgraphia (or acquired agraphia)
phonological acquired dyslexia: when the patient seems to have lost ability to use spelling-to-sound rules
can only read the words they have seen before but not new words
surface dyslexia:
anoma: loss of the ability to name things
word deafness: when cannot understand spoken words, but can read, write and speak normally
word blindness: when cannot understand written words, but can read them aloud
paralexia; when use one word for another
usually the loss of language ability
neurolinguists believe that:
that the study of language form and use will reveal the principles of brain function
study of brain function might support (or refute) specific (linguistic) theories
human brain
lower brain structures are responsible for respiration, heart rate, muscle coordination, etc.
this characteristic is shared by many mammals
cerebral cortex have folds on its surface
65% of the cortex is hidden within folds
folds have two parts
sulci
gyri
parts that are folded in
folded out
the cortex is the grey outer covering of the wrinkled mass (the cerebrum), that sits like a cap over the rest of the brain
left hemisphere controls right side of the body; and vice versa
there are two reasons to think of the cerebral hemispheres as separate brains (left and right)
hemisphere are almost completely anatomically separate
main connection between them is; bundle of nerve fibers known as the corpus callosum
corpus callosum; primary function is to allow the two hemispheres to communicate with each other
two hemispheres show considerable functional distinctness
however, specialization of isolated hemispheres should not be overestimated
studies show that neither hemisphere is competent alone in various tasks
meaning, the two hemispheres should cooperate
function of the two hemispheres of the brain
left side
right
language
speech
writing
reading
associative thought
temporal-order judgements
calculation
analytic processing
arithmetic
right visual field
holistic processing
non-verbal ideation
environmental sounds
visual-spatial skills
left visual field
pattern recognition (simple and complex)
including face, melodies, etc.
for example, being able to recognize someone in a setting, even when we only see small details/outline
we can process environmental sounds better in the left ear (since it is processed in the right hemisphere)
images of the living brain using different techniques
autopsy analysis
electrical stimulation with electrodes inserted into living brain
CT scanning
PET scan
fMRI
MEG
where is the language localized in the brain?
broca's area
located in the lower area of the left frontal lobe - left hemisphere
"consequences are associated with the damages made by a stroke or an injury"
broca's aphasia and its consequences
speech is labored and slow; lack of intonation
articulation is impaired
consonant clusters are simplified (by patients)
making speech errors: phonemic paraphrasias
response to a question will often make sense, but generally cannot be expressed as a fully formed or grammatical sentence
deep cause: the disturbance of syntactic competence
a lesia in broca's area greatly affects the production of speech; but less so in comprehension
week 9 notes (part 2)
wernicke's aphasia and its consequences
impairment in the ability to understand spoken and written language
this aphasia is a part of fluent aphasia (or sensory aphasia) and is primarily a comprehension problem
hearing is fine
speech is phonetically and even grammatically normal (including word order)
but semantically deviant because of the difficulty selecting, organizing, and monitoring their own language processing
word choices are often not fitting
jargon aphasia
1.3: brain asymmetry and handedness
examples to prove brain asymmetry
"right ear advantage" (REA)
split brain studies: