Unit 2: Methods and Approaches Flashcards
What is the method of converging operations?
When different methodologies come to the same conclusions. This increases the chance of that conclusion being the best-supported answer.
What are the critical ingredients for studying brain-behavior relationships?
A population of people to test the hypothesis on.
A way to measure behavior. May use a specific test or a battery of tests.
We need to get information from the brain.
This may include structural, functional, or modulation.
Single dissociation
An individual is impaired in one task but spared in another.
Double dissociation
Patient 1 is impaired in task A and spared in task B; patient 2 is spared in task A and impaired in task B.
Do neuroimaging results show causation or correlation?
Correlation. Inferences must be made on what the results may mean.
What are ways to increase causality in brain mapping?
Understanding the brain on a more circuit/network level.
Using Lesion Network maps could help.
Impacting different areas of the same circuit may lead to similar or dissimilar results and could lead to increased effectiveness of treatments by having a more focused treatment area.
Combining and reproducing results with different methodologies.
Standardization of methods.
Understand that different methods have different strengths in terms of how well their results can show causality.
What is the transparency assumption?
Brain damage only leads to local modifications to brain function and not global changes. The brain does not have global changes or come up with a new way of doing things.
What allows science to be self-correcting?
Science is self-correcting because as others reproduce work, they are meant to find flaws and whether ideas are applicable at different stages.
What factors are influencing the reproducibility crisis in science?
People overvalue work just because of its presence in certain journals.
Focus on quantity over quality.
Lack of healthy skepticism and willingness to criticize other scientists.
People ignore critical basic methodology design by not explaining what they did enough or not even doing them.
There are not many avenues to publish negative data, get unpublished data, or critique published data.
What are measures to increase scientific rigor?
Protect against cognitive biases
Improve methodological training
Implement independent methodological support
Encourage collaboration and team science
What are six red flags for suspect work?
Were experiments performed blinded?
Were basic experiments repeated?
Were all the results presented? Or were only the best-looking results presented?
Were there positive and negative controls?
Did the scientists confirm that they were using valid ingredients?
Were the appropriate statistical tests used?
Apophenia
The tendency to see patterns in random data.
Confirmation bias
Focusing on information that is in line with our expectations.
Hindsight bias
The tendency to see an event as predictable only after it has occurred.
What are the pros of the lesion method?
Can provide some clear deficits that provide information on the localization of different areas.
Can serve as essential comparison groups.
Can provide information on networks and plasticity.
What are the cons of the lesion method?
Some behaviors take a larger network to occur. Different lesions could provide different deficits that can be hard to untangle.
Lesions are not specific to certain areas most of the time. This can impact the degree and types of deficits.
Small lesions that do not damage a whole area may not provide a full deficit of the function.
What is the difference between structural neuroimaging and sophisticated lesion analysis?
Structural imaging allows you to see the lesion. Sophisticated lesion analysis is about determining what structures the lesions have impacted.
Contemporaneous
Things occurring at the same time. This allows the ability to see the deficits while the behavior is occurring and observe the brain activity with neuroimaging.
What is lesion-symptom mapping?
The region of damage is manually assessed for each patient and then using behavior to figure out what each region is responsible for.
How are comparison groups important for the lesion method?
Comparison groups are important to help localize lesions more. By having different comparison groups, using double dissociations, and subtracting neuroimaging results, you can narrow the localization of different functions.
Why is the lesion method still important today?
Neuroimaging can provide other information to see what areas are active when and how much. This can highlight different networks. The plasticity and compensatory methods can be observed in lesion patients as well.
Lesions may be essential comparison groups for the associated behavioral deficit and impacted brain area.
How does fMRI measure brain activity?
As fMRI tracks blood flow by changes in oxygenation, the parts of the brain that take in oxygen during behavior are thought to be related to the behavior.
What is the subtraction method in neuroimaging?
The subtraction approach subtracts activity seen in behavior from similar but unrelated behaviors and baselines. Brain activities together from multiple participants may be averaged together to get a composite image.
Why is it important to know the baseline for functional imaging?
Knowing what baseline was used for the participants can help standardize images. If there are many different baselines, then the results after subtraction may not be comparable.
What are the advantages and disadvantages of the subtraction method for neuroimaging?
Advantage: Remove some background noise
Disadvantage: Possibility of missing potential valuable signals as areas could be active for multiple different behaviors.
What are the main advantages of functional neuroimaging?
The benefits are that it has high spatial resolution and okay temporal resolution. You can observe multiple types of behavior in fMRI. It is non-invasive as well.
