Lecture 4 Flashcards
What are the 6 lobes of the cerebrum called?
- frontal
- parietal
- occipital
- temporal
- central (insula)
- limbic
What happens to the space occupying legion in the parietal lobe?
Debulked
Which layer is the thickest in the visual lobe?
III 3a, 3b, 3c
What do the cells of the visual lobe do?
Import visual information to the motor cortex
What are the thickest layers in the motor cortex?
V and VI
What did Brodmann discover?
He used Nissl staining to see that each area has discrete patches
According to the Brodmann’s map what are areas IV, XVII and I?
IV: motor cortex
XVII: visual cortex
I: sensory cortex
What is the cortical structure?
Has layers of neocortex
What is distinctive about neocortex II, IV and V?
II: small pyramidal cells
IV: stellate cells
V: large pyramidal cells
Who is Phineas Gage?
Someone who had damage to the frontal lobe and became aggressive and a drunk as a result
What has the case of Phineas Gage proven?
That the orbital frontal lobe contributes to personality
What is Brocha’s aphasia?
“Expressive aphasia”
Impaired speech; odd word structure, grammer and syntax
How is Brocha’s aphasia typically caused?
Left frontal lobe damage
What is Wernick’s aphasia?
“Fluent aphasia”
A receptive aphasia in which the speaker seems fluent but uses contrived/inappropriate words. Lacks comprehension
How is Wernick’s aphasia typically caused?
Posterior temporal lobe damage
What are examples of methods of modern mapping?
PET scanning
Functional MRI (fMRI)
Regional blood flow
How was PET scanning used to see the function of areas involved in language?
- Visual cortex:
The word “car” is seen in the visual cortex - Primary auditory complex (Wernick’s area):
Wernick’s area conceives of he verb “drive” to go with “car” - Premotor cortex (Brocha’s area)
Brocha’s area compiles a motor program to speak the word “drive” - Primary motor cortex
The primary mortor cortex executes the program and the word is spoken.
How does PET scanning work?
- Inject radioactivity glucose
- produces gamma rays
- glucose is taken up in part of the brain
- hat part is being activated
(diagostics than research)
What is advantage and disadvantage of PET scanning in brain mapping?
Pros: Can see changes happening in real time
Cons: Images are blurred
How does fMRI scanning work?
Looks for bloodflow in the brain;
more active means more blood
able to detect changes in bloodflow
overlay image over structure of brain
What are the advantages of fMRI?
better spacial recognition and the test subject can do various tasks in the MRI machine
What is the association cortex?
Most cortical area: the “silent” areas that support the primary cortex
What does the association cortex do?
Input from many sources - modalities
Is the association complex highly developed in humans?
yes
What is the left hemisphere mostly lateralized for?
speech, calculation, analysis
What is the right hemisphere mostly lateralized for?
spatial, conceptual, artistic
How does lateralization occur?
Differential hemisphere gene expressionin development
How does alien hand phenomenon occur?
Through callodectermy
What is the alien hand phenomenon?
E.g. can draw a circle using one hand while drawing a square with another
Where is the basal ganglia located?
Deep within hemispheres
What is the basal ganglia associated with?
Movement
What are disorders associated with the basal ganglia?
Parkingson’s and Huntington’s
What does the striatum consist of?
Caudate and putamen
What does the limbic system control?
Reticular formation; emotions, memory, motivation
What are two structures that are part of the limbic system?
Hippocampus and amygdala, hypothalamus and thalamus
What is a condition caused by a severed fornix?
Capgrar syndrome: emotional and memory parts are severed
What is an example of someone with Capgrar syndrome?
A man cannot recognize his mother and thinks she is an imposter
What has Capgrar syndrome suggested?
Emotions intertwine with memory alongside images
What do the association fibers, th commissural fibers and the projection fibers form?
Cerebral fiber tracts
What do the association fibers do?
Link areas within a hemisphere
What do the commissural fibers do?
Connect between hemispheres
What do the projection fibers do?
Link to non-cortical areas
What are the components of the association fibers?
arcuate fibers longitudinal fascicula corpus callosum internal capsule anterior commissure
