25 Flashcards
(25 cards)
What is the difference in personality symptoms between frontal lobe patients with left brain damage and right brain damage? What were the now semi-retired labels for these personality change constellations?
Personal behavioral control (changes in personality) – impaired response inhibition, deficient associative learning, increased risk-taking and rule violation, gambling, self- regulatory disorder, impaired social behavior, altered sexual behavior
i. Left Side Damage – pseudodepression
1. Outward apathy, indifference, loss of initiative, reduced sexual interest,
little/no verbal output
ii. Right Side Damage – pseudopsychopathy
1. Immature behavior, lack of tact/restraint, promiscuous sexual behavior,
coarse language, lack of social graces, increased motor activity
What is the difference in emphasis between the terms cerebral asymmetry, hemispheric specialization, cerebral dominance and lateralization of function?
a. cerebral dominance: one side rules over the other
b. cerebral asymmetry: differences between the two cerebrums
c. hemispheric specialization: different parts of the brain are specialized in different
functions
d. cerebral lateralization: tendency for some cognitive functions to be specialized to one
hemisphere over the other
Which side of the brain has the longer Sylvian fissure? Which side of the brain has the steeper Sylvian fissure? (see slide)
a. Longer Sylvian fissure – left hemisphere
b. Steeper Sylvian fissure – right hemisphere
Which side of the brain has the larger inferior posterior parietal lobe area? (see slide)
Right
Which side of the brain has the larger planum temporale? (see slide)
Left
Which side of the brain has a larger Heschl’s gyrus (or even gyri)? (see slide)
Right
What is Wada test for? What is the principle behind the Wada test? What is the procedure for the Wada test?
Wada test – used to find out how each hemisphere functions and what functions are carried out on each side
i. principle: anesthetize one hemisphere and see what the other does
b. Procedure: drug sodium amytal is injected into the carotid artery to anesthetize one side
i. test are done to see the functions
ii. left side was found to be dominant in language
What is the corpus callosum and what is the function of the corpus callosum?
Corpus callosum – connecting axons between hemispheres, connections connect homologous regions of cortex of each hemisphere
i. Function – sharing information between cerebral hemispheres
ii. 20th century – lack of symptoms (humans transsected corpora callosi, born
without corpus callosum (agenesis)
iii. Careful testing of learning in animals with split brains – learning in lower
animals happens in both hemispheres
What is a commisurotomy of the corpus callosum?
Commissurotomy – severing of the corpus callosum used to treat severe seizure disorders
How can the hemispheres in a typically lateralized patient with commisurotomy of the corpus callosum respond to questions? (see video)
a. Left hemisphere – tell what it has seen or heard, stronger in tasks involving language
b. Right hemisphere – show what it has seen or heard, could not communicate, could
understand language
What were the interesting findings w.r.t eyedness during the class experiment?
Showed differences in dominant eyes when focusing
What percentage L and R handers carry their language in the L hemisphere, R hemisphere and bilaterally approximately?
a. 98% of right handers (dextrals) in the L hemisphere
b. 70% of left handers (sinestrals) carry in L hemisphere
c. Of right handers, 95% carry lang. in their left hemisphere, 5% right
d. Of left handers, 70% carry language in left, 15% right, 15% bilaterally
i. Left-hemisphere dominant in almost all dextrals and most sinestrals
What is the difference in lateralization between males and females? (see slide)
a. females are less lateralized, may use both hemispheres more often for language tasks than men do
b. both use hemispheres for language tasks
What are the reliable sex differences in abilities? (see slide)
What is plasticity? What is the obvious means by which we know that the brain is changing all the time? At what levels of description can you look for plasticity?
Plasticity – how the brain changes during the whole life span
i. Learning and remembering new things (hippocampus developing) and changes in
cortical maps
ii. Microscopic changes (synaptic organization, molecular structure, mitotic activity,
exposure to drugs)
What did the juggling study show with regard to plasticity?
a. 1st brain scan – inexperience in juggling, given 3 months ot learn juggling routine
b. 2nd brain scan – skilled performers
c. 3rd brain scan – no longer fluent in juggling
d. Showed: gray matter increased in brain regions involved in complex visual motions,
CHANGE IN BRAIN VOLUME IF YOU TRAIN A CERTAIN SKILL
At what levels of description can you look for plasticity?
Behavioral level: Changes in skill or performance (e.g., learning to juggle or read Braille).
Cortical map level: Reorganization in brain areas such as motor, sensory, or visual cortices in response to use, training, or injury.
Neuroanatomical level: Physical changes in brain volume or structure (e.g., violinists showing enlarged motor areas).
Functional level: Shifts in brain activity patterns during tasks or at rest (e.g., increased activation in somatosensory cortex for Braille readers).
Cellular/molecular level: Synaptic growth, pruning, or neurotransmitter changes due to experience.
What are essential tremors?
a. Essential tremors – nervous system (neurological) disorder that causes involuntary and rhythmic shaking, affect almost any part of your body, but the trembling occurs most often in your hands — especially when you do simple tasks, such as drinking from a glass or tying shoelaces
b. no idea what is causing it
What was the general finding w.r.t. drugs of abuse and plasticity?
Drugs can change brain circuits and affect learning and reward systems
- limits other plasticity
What is diaschisis? In what sense is it distal?
a. Diaschisis (distal) – person suffers stroke, brain loses oxygen, brain cells die
i. Distal – brain has huge connectivism, one area dies, resulting connections
silenced
What is the recovery path in hemiplegia?
a. Hemiplegia – half of body not working due to stroke
i. Parallel to development of reaching and grasp in infants – relatively slow
ii. Few months to regain motor movements, last to develop is fine motor control
What is a hemispherectomy? In what types of situations is it carried out? What is the main recovery variable? What is the usual age window for successful hemispherectomies?
Hemispherectomy:
Surgical procedure in which half of the brain is removed or disconnected
Carried Out:
Severe, intractable epilepsy
Major trauma or malformation affecting one hemisphere
Main recovery variable:
Age at the time of surgery, the younger the better
Age window for successful hemispherectomies:
0-1 likely better
1-6 best time, earlier is better
After 6 more cautions
What is constraint induced movement therapy? Explain how it works?
Constraint-Induced Movement Therapy (CIMT) is a stroke rehab method that helps you “re-teach” your brain to use a weaker arm or hand by:
Restricting your strong limb (e.g. wearing a mitt or sling) so you can’t rely on it.
Practicing simple tasks (reaching, grasping, picking up objects) over and over with your weaker limb.
Building new brain connections through repetition, which gradually makes that limb stronger and more coordinated.
Who are candidates for constraint induced movement therapy? What is a major factor in all rehabilitation?
a. Candidates – stroke victims, children with cerebral palsy/upper extremity hemiplegia
i. Major factor – setting goals
