Final exam Flashcards
Compare and contrast the visual symptoms associated with lesions of the inferotemporal cortex.
- Temporal lobe lesions: affect the patients ability to attend to object in the contralateral field of vision, it can also affect the ability to recognize and name objects.
- Parietal lobe lesions: Visuomotor or orientational. Causes optic ataxia: inability to guide hand towards an object with visual information.
- Both: contralateral neglect
What techniques permit the study of cerebral asymmetries in neurologically normal individuals?
- behavioral testing (divided visual field)
- spreading depression (wada test)
- studying patients with developmental abnormalitites
- fMRI + behavior/perception/cognition
- PET + behavior/perception/cognition
- MEG + behavior/perception/cognition
How could PET technology contribute to our knowledge of different visual areas in the occipital lobe
- PET if a functional imaging technology that allows us to see metabolic processes. When you inject the subject with radioactive sugar, you can see with the PET scan what part of the brain is metabolizing the most sugar. Then, if you show the subject a stimulus, you will be able to see what visual area is metabolizing the most, and you will be able to associate that area with the stimulus.
Briefly describe the insight of Cormack and Hounsfield that led to the development of the Computerized Axial Tomograph or CT scan.
Hounsfeild was a British scientist who worked for electric and music industries. He developed the first practical CT machine also known as the EMI scanner. Hounsfeild and Cormack independently developed the tomograph, a way to create three dimensional images of a part of the body by taking many x-ray images and combining them. They both were awarded the 1979 Nobel prize for their work on the CT machine.
Why is neuropsychological testing particularly useful in cases of closed-head injury?
Battery testing: a series of behavioral measures designed to evaluate the patient’s perceptual and cognitive abilities. It is particularly good for closed-head injuries where multiple brain systems could have been affected.
Neuropsychological testing is used to identify a cognitive disturbance and differentiate between factors that could cause the cognitive impairment. Battery testing is one form of neuropsychological testing.
List five symptoms associated with temporal lobe dysfunctions and the hemisphere with which the symptom is specifically associated.
Right hemisphere:
- Deficits in non-verbal memory (such as faces)
- deficits in processing music
Left Hemisphere:
- deficits in verbal memory
- deficits in processing speech sounds
- understanding written and spoken language
- Wernicke’s area: fluent aphasia
Name four cognitive skills impaired by damage to the dorsolateral pre-frontal cortex.
Selective attention, planning behaviours, making decisions about risks, comparing memories
Describe the Stroop Effect and explain how it is demonstrated. What aspect of cognition appears to be responsible for the Stroop Effect and which part of the brain is believed to mediate it?
The stroop effect is the ability to say the colour a word is written in without reading the word itself.
The part of cognition needed is the part that recognizes colour, but its necessary to repress the part that deals with word encoding.
-cant be done with a frontal lobe lesion
-mediated by anterior cingulate cortex & dorsal prefrontal cortex
Why may faces be ‘special’ in terms of brain processing?
- The fusiform gyrus has a lateral area called the fusiform face area.
- Facial recognition matches perceived faces against those stored in long term memory
- the inability to recognize faces is called prosopagnosia, and is caused by damage to the fusiform face area
Compare and contrast the relative spatial and temporal resolution capabilities of Event related potentials (ERPs), Positron emission tomography (PET) and functional magnetic resonance imaging (fMRI).
Spatial resolution: how well can it perceive parts of the brain, and how well can it perceive the stuff its doing.
Temporal resolution: how often it can perceive stuff.
ERP: unreliable spatial resoluion. best temporal resolution.
PET: very good spatial resolution. temporal resolution is the worst.
fMRI: best spatial resolution, with good temporal resolution (better than PET, worse than (ERP)
Distinguish between ‘vision for action’ and ‘action for vision’
- vision for action is vision used to guide movements and behaviors. It is controlled from the dorsal stream to the parietal lobe.
- action for vision is vision used to obtain qualitative information about an object such as colour or shape.Uses the ventral visual stream from the visual cortex to the to the medial temporal lobe.
What are the basic ideas in the Geschwind-Galaburda theory concerning the development of cerebral asymmetry.
Geschwind and Galaburda proposed a theory of cerebral lateralization based off the hypothesis that fetal testosterone levels change neural development, neural crest development, and immune development. This can help explain learning disabilities, and explain why females and males mature at different rates.
What is typically wrong with a patient who can draw a simple object more accurately from memory than from referencing a visual example?
They have constructional apraxia. It affects the ability to draw or copy objects. This is a common symptom after having a right parietal stroke.
Describe the functions of the dorsolateral prefrontal cortex.
executive functions, planning, manages cognitive processes, threat induced anxiety, acts of deception.
- it creates and maintains temporal order, including regulation in thinking and action.
- dorsal pathways primarily terminate in the dorsolateral prefrontal cortex.
Compare and contrast the symptoms encountered by patients with damage to the dorsal vs the ventral streams of vision.
- Damage to the dorsal stream causes apraxia, which is not being able to program movements based off of locations of objects.
- Damage to the ventral stream causes aphasia. which is not being able to identify and object, or an object’s features.
Name three problems associated with the use of ‘cutoff’ scores in neuropsychological test batteries.
- battery tests are tests that use behavioral measures to evaluate the patient’s cognitive and perceptual abilities.
- they are expensive
- they are time consuming
- they are difficult to automate
- they only differentiate between neurologically normal individual and brain-damaged individuals, and does not actually determine a cause.
How would you describe the functions of the posterior zone of the parietal lobe in humans? Provide an example from everyday life
- The prosterior zone of the parietal lobe plays an important role is planned movements, spatial reasoning and attention.
- damage to this area would affect your ability to have planned movement and would cause poor spatial reasoning.
- an example of something in everyday life that this part of the brain would play a roll in is brushing your hair.
Discuss the advantages and disadvantages of computerized neuropsychologic testing.
Advantages:
- standardized administration
- reduces individual differences
- the tests are like games, more fun for the subjects
- saves time due to immediate results
Disadvantages:
- lacking observations
- researchers sometimes using non-approved tests
- no qualitative variables
- anonymity
- lack of premorbid norms
- stardardized
List four of the five general categories of visual functions and provide an example of each.
- vision for action. ex)catching a ball
- action for vision. ex)eye movements
- visual recognition ex)recognizing a face
- visual space perception. ex) knowing where something is relative to yourself.
Gender differences have been observed for at least five cognitive abilities. List any four of these.
-relational empathy in women
-autism more prevalent in men
-systematic thinking in men
logical thinking in men
