Studying the Brain (+ research design)

steps of the scientific method

1) generate a testable question (narrow area)
2) gather data and resources (literature search)
3) form a hypothesis
4) collect new data (experiment or observe)
5) analyze the data
6) interpret the data and existing hypothesis
7) publish
8) verify results (repeat under new conditions)

what does FINER stand for?

Feasability
Interest
Novel
Ethical
Relevant

positive vs negative controls

positive controls are when you know a change will happen while negative controls are when you know no change will happen

accuracy

also known as validity, is the ability of an instrument to measure a true value

precision

also known as reliability, is the ability of the instrument to read consistently or within a narrow range

randomization

the method used to control differences between subject groups in biomed research

blinding

subject and/ invesitgator does not have info about which group subject is in

cohort studies

subjects are sorted into groups based on differences in risk factors (ie. smokers vs non-smokers in developing lung cancer) and then assessed at various intervals to determine how many subjects each group had a certain outcome

cross-sectional studies

categorize patients into different groups at a single point in time

case-control studies

identify the number of subjects with or without a particular outcome, and then look backwards to assess how many subjects in each group had exposure to a particular risk factor

Hill’s criteria

• temporality: exposure must occur before outcome

• strength of the relationship

• dose-response relationship

• consistency of findings

• plausibility: reasonable mechanism for IV to impact DV

• consideration of alternative explanations

• experiment or correlational study

• specificity: change in DV specific to associated change in IV

• coherence with established facts

patients in a study for a given weight loss drug may begin exercising more frequently or may make healthier diet choices, thus artificially increasing the percieved effect of the drug. What is this an example of?

the Hawthorne effect or observation bias (behaviour of study participants is altered because they know they are being studied)

high BP and diabetes mellitus are more common in the obese population; thus a physician may screen obese patients for hypertnetions and diabetes at a higher rate than healthy-weight patients, inflating the true value of the secondary measurement. what is this an example of?

detection bias (educated professionals using their knowledge in an inconsistent way)

beneficence

the obligation to act in the patient’s best interst

nonmalificence

the obligation to avoid treatments or interventions in which the potential for harm outweighs the potential for benefit

respect for persons

the need for honesty between the subejct and the researcher, generally prohibits deception. includes the process of informed consent

a) Binding to an enhancer sequence for a gene that codes for an enzyme in the dopamine synthesis pathway
b) Binding to an allosteric site on monoamine oxidase
c) Inhibiting the reuptake of dopamine
d) Decreasing transcription rates of monoamine oxidase

b) Binding to an allosteric site on monoamine oxidase

In the question stem it specifically mentions that compound X inhibits the action of monoamine oxidase. From that, we know compound X must increase dopamine through direct interaction with monoamine oxidase, not by affecting other transporters or transcription.

a) I only
b) I and II only
c) I, II, and III
d) II and III only

c) I, II, and III

To learn more about fetal rat brain development, researchers inject rat brains with lipopolysaccharides (LPS) while the rats are developing in the mother's womb. Why would microglia be the most impacted by the injection?

A team of researchers studies how addiction affects the mesocorticolimbic pathway in the brain. They used a dopaminergic receptor antagonist (D-At) with a moderate dissociation constant to inhibit the effects of dopamine in that pathway. Why would cortical cooling of the postsynaptic neuron be the best choice to mimic the receptor antagonist?

A stroke victim presents with a lesion in their left temporal lobe. Upon assessment, the patient appears to be able to speak fluently but some of the words don't make any sense. When asked questions, the patient does appear to understand. When asked to repeat words or phrases the patient is not able to. How do the symptoms point towards conduction aphasia?