Research Flashcards
What’s a theory?
Give an example
A set of propositions meant to explain a class of observations
Example: Low serotonin causes major depression
Whats a hypothesis?
Give an example
Expectations of what should occur if the theory is correct.
Example:
Lower serotonin levels found in ppl who are severely depressed
Higher serotonin levels will alleviate depression
if reduced in healthy ppl, may cause depressive symptoms to appear.
What should scientific theory be?
Principles clearly defined
Based on reproducible data
Refined/abandoned in light of new evidence
What should scientific theory not be?
Based on anecdotal evidence, ie. intuition/opinion
Impossible to disprove
Based exclusively on explanations of pre-exciting data after the results are known, ie. forming a hypothesis after the results are known
What are the key research methods in psych disorders?
- Case studies
- Correlational research
3.Epidemiological studies
- Genetic studies
- Experimental research
- Clinical trials(Treatment outcome research)
- Analogue experiments
- Single case designs
- Meta analysis
What are case studies?
Collecting and reporting on rich information on one person
Used to generate a hypothesis which can later be tested
The method for reporting is important but incredibly rare phenomena
What are some examples of case studies
Albert
Nim Chimpsky- trying to get chimps to learn a language
Phones Gage- personality change following damage to the prefrontal cortex
Whats correlational research
Example
Studying the relationship between two variables
More exercise is correlated with lower levels of depression
but correlation does not equal causation
explanations
3rd variable
exercise releases endorphin
depression makes ppl less likely exercise
Correlation does not equate to causation
More dolphins are pink
Dolphins love ice cream
loving ice cream doesn’t make u go pink
What are epidemiological studies
Survey large groups of ppl to get a picture of the entire population
What is incidence?
The proportion of people who develop new case of the disorder in some period, usually a year
Can be cross sectional or longitudinal studies
What is prevalence?
The proportion of people with the disorder either currently or during their lifetime
What are risk factors?
Variables that are related to the likelihood of developing the disorder
What is another method of genetical study other than knockout studies, what does it do?
Genome Wide Association Studies (GWAS)
Examine relationship between depression and 20,000-25,000 genes with no explicit hypothesis.
What is experimental research
Manipulate a variable and make it an independent variable
Observe the effect that has on a dependant variable
Allows us to test for causal relationships
IS virtual reality as effective as real life exposure
33 patients with acrophobia
Randomised to one of two groups
One group receives VR exposure (experimental group)
One group receives standard exposure (control group)
Not a lot of difference n the results, VR may be a less expensive, less time consuming
Not a lot of difference n the results, VR may be a less expensive, less time consuming
Is this a valid conclusion?
Internal validity
Is the result confounded, ie is there a different factor driven the results
Example: If the person spent more time in VR than the person doing it IRL
External validity
Will it extend to exposure for other phobias?
What is treatment outcome research
Clinical trials
How is it assessed if a clinical trial will work
Randomised control trials
A person is randomly assigned and is either given the experimental treatment or a control treatment
What are some issues that present in randomised control trials and how are they reduced?
Expectations influence treatment outcome
The type of ppl who sign up may believe that the treatment will work, ie. selection bias
Placebos are given to control for expectations
Expectations also bias researchers through confirmation bias
So double blind procedures help protect against this
What are analogue experiments
Covers wide range of approaches- share common features
Rationale: Where its challenging to test the hypothesis that you want to test you randomly assign ppl to receive some type of trauma
Group 1- exposed
Group 2- control exposure
This is unethical
What are the types of analogue experiments?
- Create a laboratory model
- Use subjects similar to a patient population
- Animal models
How do you create a laboratory model
give the example
Co2 given to induce panic attacks in healthy subjects
Its safe and reversible
And has been used to study medications and the physiology of panic attacks
Use subjects similar to a patient population
Recruiting patients is difficult
Can just recruit ppl from a community that have elevated levels of symptoms
What is the animal model
Does chronic stress increase risk for depression?
Linking stimulus to causal relatons
Exposing rats to unpredictable electric shocks/ cold temperatures/ pinching their tails
Studies still employed to this day
The rats more exposed to these procedures are more depressed and giving the rats an antidepressant relieves it
Why are animal models not as accurate?
Rats are smaller
What is depression in rats- u can’t ask them how they feel
What are single case designs?
Study of individual cases
Manipulate the timing and nature of experimental conditions
With frequent repeated measurement
Example: person normally treat them, make them withdraw and reintroduce
What is meta analysis?
Statistical summarisation of results across numerous studies- compilation of effect sizes
Example: Asking if cognitive behavioural threader is better for OCD than control treatments
Analysed 16 outcome studies w 756 patients
YES CBT for OCD was more effective than the control
What are some caveats to meta analysis
Only as good as the data collected.studies published
Publication bias
Convergence
What is publication bias?
where studies that fail to show an effect are less likely to be published
What is convergence?
No method is a solution.
