CSD 431 QUIZ 1 QUESTIONS WITH CORRECT
ANSWERS
corpus callosum and split brain
- Answer--houses more than 100million axons and interconnects the
two hemispheres
-when corpus callosum is split it can help treat epilepsy. Split brain shows us that hemispheres
function independently of one another
Double Dissociation- Answer--2 different patients display diametrically opposed patterns of
performance on 2 different tasks. Provides compelling evidence that 2 tasks rely on at least partially
segregated cognitive mechanisms
-patient A performs significantly worse on task X than task Y and patient B performs significantly
worse on task Y than taks X
Group Studies- Answer--allow researchers to test hypotheses about correlations between disturbances
of particular mental abilities and lesions in particular brain regions
-Need to include large number of patients with and without impairment and injury of interest to
reliably conclude that a certain deficit is a result from damage to a specific area
-Great for testing hypotheses about universality of specific-behavior
brain relationships
-ignore distracting individual variability
-test reliability of deficit
-lesion correlations
Limitations of Group Studies
- Answer--how carefully the behavioral criteria from the group
membership are formulated. Because of this group studies need to specify type of impairment that
serves as main behavioral factor for sorting patients
-when you define something as a syndrome it can have a very loose variation of symptoms and each
patient might vary completely. Leading to determine if you sort patients by presence or absence of a
specific symptom instead of syndrom. This can even varyhow
at specifically you define a symptom
Case Studies- Answer-we can get a lot of information from intensely studing a patient such as HM
(hippocampus) and SM (amygdala)
stroke- Answer--blood supply to a particular part of brain is disrupted
-localized because stroke typically effects one area
ischemic- Answer-blood vessel becomes obstructed by a clot, depriving the stream of oxygen
, thrombotic- Answer-clot forms when blood vessel gets clogged. Buildup on artery
embolic- Answer-clot originated elsewhere and blood tapers off elsewhere. clot is travelling
Traumatic Brain Injury- Answer--can be open or closed head
-if it is close damage is diffused like in a concussion
-if damage is open you are more likely able to localize
Neurodegenerative and Infectious Diseases - Answer--lead to progressive atropy in specific regions or
sets of regions in the brain
-common diseases include alzheimers, parkinsons, huntingtons, MS
-vary on if local or diffused; can be focal but usually more diffuse
tumor- Answer--a mass of tissue that grows abnormally and serves no physiological purpose
-most common is glioma
-classified according to how they grow and likelihood of recurrence post removal
Lesion overlap and subtraction analysis
- Answer-the superimposed lesion sites of patients with a
particular deficit are contrasted agains superimposed lesion sites of patients without deficit. Brain
image resulting from subtraction reveals areas of damage
linked with deficit
Voxel-Based lesion symptom mapping - Answer--you administer a task of interest to a group with
widely distributed lesions. For each voxel, two groups of patients are formed
--those with and without
lesions at that voxel. At all voxels where number of patien
ts in both groups exceed a certain threshold,
the data is behaviorally compared between groups. This defines the degree to which decreasing task
performance is tied to damage to an area
-used to define neural underpinnings of deficit and quantify brain behavior relationships in an analoge
manner without having to classify patients according to impairment
caveats to studying lesion
-deficit correlations- Answer--necessary to demonstrate not only patients
with lesions have the deficit, but that patients with the deficit have lesions at that site
-chronic period can have an impact on results: for example if TBI patient is over or under 6 months
from the injury then the results could vary
-some impairments cannot be seen on an mri
hypoperfusion- Answer-a brain area receives enough blood supply to survive but not enough to
operate normally
ANSWERS
corpus callosum and split brain
- Answer--houses more than 100million axons and interconnects the
two hemispheres
-when corpus callosum is split it can help treat epilepsy. Split brain shows us that hemispheres
function independently of one another
Double Dissociation- Answer--2 different patients display diametrically opposed patterns of
performance on 2 different tasks. Provides compelling evidence that 2 tasks rely on at least partially
segregated cognitive mechanisms
-patient A performs significantly worse on task X than task Y and patient B performs significantly
worse on task Y than taks X
Group Studies- Answer--allow researchers to test hypotheses about correlations between disturbances
of particular mental abilities and lesions in particular brain regions
-Need to include large number of patients with and without impairment and injury of interest to
reliably conclude that a certain deficit is a result from damage to a specific area
-Great for testing hypotheses about universality of specific-behavior
brain relationships
-ignore distracting individual variability
-test reliability of deficit
-lesion correlations
Limitations of Group Studies
- Answer--how carefully the behavioral criteria from the group
membership are formulated. Because of this group studies need to specify type of impairment that
serves as main behavioral factor for sorting patients
-when you define something as a syndrome it can have a very loose variation of symptoms and each
patient might vary completely. Leading to determine if you sort patients by presence or absence of a
specific symptom instead of syndrom. This can even varyhow
at specifically you define a symptom
Case Studies- Answer-we can get a lot of information from intensely studing a patient such as HM
(hippocampus) and SM (amygdala)
stroke- Answer--blood supply to a particular part of brain is disrupted
-localized because stroke typically effects one area
ischemic- Answer-blood vessel becomes obstructed by a clot, depriving the stream of oxygen
, thrombotic- Answer-clot forms when blood vessel gets clogged. Buildup on artery
embolic- Answer-clot originated elsewhere and blood tapers off elsewhere. clot is travelling
Traumatic Brain Injury- Answer--can be open or closed head
-if it is close damage is diffused like in a concussion
-if damage is open you are more likely able to localize
Neurodegenerative and Infectious Diseases - Answer--lead to progressive atropy in specific regions or
sets of regions in the brain
-common diseases include alzheimers, parkinsons, huntingtons, MS
-vary on if local or diffused; can be focal but usually more diffuse
tumor- Answer--a mass of tissue that grows abnormally and serves no physiological purpose
-most common is glioma
-classified according to how they grow and likelihood of recurrence post removal
Lesion overlap and subtraction analysis
- Answer-the superimposed lesion sites of patients with a
particular deficit are contrasted agains superimposed lesion sites of patients without deficit. Brain
image resulting from subtraction reveals areas of damage
linked with deficit
Voxel-Based lesion symptom mapping - Answer--you administer a task of interest to a group with
widely distributed lesions. For each voxel, two groups of patients are formed
--those with and without
lesions at that voxel. At all voxels where number of patien
ts in both groups exceed a certain threshold,
the data is behaviorally compared between groups. This defines the degree to which decreasing task
performance is tied to damage to an area
-used to define neural underpinnings of deficit and quantify brain behavior relationships in an analoge
manner without having to classify patients according to impairment
caveats to studying lesion
-deficit correlations- Answer--necessary to demonstrate not only patients
with lesions have the deficit, but that patients with the deficit have lesions at that site
-chronic period can have an impact on results: for example if TBI patient is over or under 6 months
from the injury then the results could vary
-some impairments cannot be seen on an mri
hypoperfusion- Answer-a brain area receives enough blood supply to survive but not enough to
operate normally
