research methods Flashcards
(39 cards)
1
Q
fMRI scans
A
1) detects changes in blood flow & oxygenation that occur in response to neural activity
2) when brain area is more active, it needs more O2 so more blood with oxygenated haemoglobin flows to area
3) oxygenated blood repels but deoxygenated blood follows direction of magnetic field
4) scan can detect these diff magnetic qualities & so be used to create 3D map of brain
2
Q
PET scans
A
1) radioactive tracer is combined with flurodeoxyribose & injected into patient
2) after some time, p is placed in computer scanner
3) when H+ and e- collide gamma rays are emitted which are detected by the scanner
4) detected emissions are plotted (sometimes as a 3D plot) & brain activity is recorded
3
Q
PET & MRI strengths
A
- PET shows you chemical processes occuring in brain (eg: glucose uptake, raine 1997) unlike other methods & don’t need to stay really still like MRI
- fMRI scans are less invasive as emits less radiation & no injection SO good 4 patients that need multiple scans as lower risk of radiation damage eg: mutations, cancer
4
Q
fMRI - weaknesses
A
- temporal resolution (how quickly a scan takes to detect changes) is POOR (1-4 secs) - means can’t accurately use it to predict changes in brain & doesn’t provide direct measure of neural activity, just detects blood flow so diff 2 establish causation at neural level
5
Q
PET - weaknesses
A
- spatial resolution is poor (esp. in comparison to fMRI) so can’t detect really small measurements & more invasive as injection & radiation - due to risk which radioactive isotope causes can only be done a few times
6
Q
primary data
A
- original data that researcher has collected first hand from ps themselves spec. for study
- eg: experiments, questionnaires, observations
- adv: data has been specifically collected 4 study’s purpose, can ensure reliable & scientific methods have been used, & don’t have to sort through irrelevant info
- dis: takes a lot more time, £ & effort to collect data this way as you have to recruit your participants, carry out the experiment and then record your results
7
Q
secondary data
A
- data that already exist & has been examined (collected by someone other than original researcher)
- eg: psych journals articles, gov reports, pop records
- adv: doesn’t take as much time, effort or money as P.D
- dis: may not be relevant & quality of data will vary as some may be outdated, not useful or incomplete
8
Q
content analysis
A
- obeservational research where peepes are indirectly studied via communications (spoken, written or from media eg: newspapers)
- data is coded OR analysed 2 identify themes (key ideas)
- coding - qualitative into quantative & large data sets into meaningful units
- thematic analysis - produces descriptive, qualitative D
9
Q
random
A
- everyone in target pop is assigned a no
- random no. generator is used to select no.
- those with no. selected becomes part of sample
- adv - everyone has equal chance of being selected (unbiased), cheap & uncomplicated compared 2 others
- dis - sample chosen may not be rep of target pop, hard to get list of every individual when pop is large
10
Q
systematic
A
- get a list of target pop, choose starting point & select every nth person in pop (for sample)
- adv - unbiased as using objecteive system, prevents a cluster selection of ps as evenly selected
- dis - sample chosen may be unrepresentaive (by chance) & may be time consuming to create a list for large data sets
11
Q
volunteer
A
- ps choose/volunteer to be involved in study (eg: respond to ad)
- adv - more likely to consent as they’re coming to you & have access wide variety of ps (eg can post ads in multiple places) which could lead to more repsentation
- dis - ad may only attract certain types of people (eg: those interested in psych, highly motivated or desperate 4 £) & not be posted where everyone can see it
12
Q
snowball
A
- ps are recruited via word of mouth or from ps of study referring their aquaintances, used for research where ps are difficult to locate
- adv - researcher doesn’t have to spend as much time or effort recruiting ps, lower attrition rate as ps refer people they know will be committed, helpful in situations where ps are hesitant to participate & chain referal process allows psych to access pops that are difficult 2 sample
- dis - likely to end up with biased sample as ps will recruit people they know & thus likely share similar characteristics, referals may be unwilling to co-operate
13
Q
opportunity
A
- ask whoever is available at the time
- adv - quick, easy & cheap
- dis - likely to end up with biased sample as researcher will be more likely to recruit those they think will be helpful (researcher bias) & only choosing from small subgroup of target pop
14
Q
quota
A
- divide target pop into sub categories based on certain characteristics
- use non-random sampling technique (eg: snowball, opportunity) to choose ps from each group in proportion to how often they occur in pop
- adv - subgroups ensure sample is rep of target pop & non random methods tend to be more conveniant
- dis - non random methods are prone to bias & process time consuming & costly as involves lots of steps
15
Q
stratified
A
- divide target pop into sub categories based on certain characteristics
- use random sampling techniques (eg: random, systematic) to choose ps from each group in proportion to how often they occur in target pop
- adv - subgroups helps ensure sample is representative & random methods helps sample be unbiased
- dis - time consuming & costly as lots of steps involved & may end up with biased sample by chance
16
Q
event
A
- use bev schedule to record no. times a bev occurs whilst observing ps (b.s will have categories - eg: for anger, kicking & screaming)
- may lack detail as doesn’t give info about events that occur before or after observation or obs that are relevant to bev but not listed on b.s
- useful when you need to record many bevs & easy to replicate as can use same b.s
17
Q
time
A
- record no. time a bev occurs within a specific time interval (eg: every minute)
- bev that occurs between intervals will be missed & bev record at each interval may not be represenative
- useful when you need to record many bevs & easy to replicate as diff raters can use same time intervals
18
Q
case study
A
- detailed investigation of on individual or small group (eg: HM, phineas gage) - data may be obtained from interviews with ps, their guardians, teachers, courts, ect., us. about unusual phenomen or event of interest
- adv: can do on rare cases, where other methods would be impratical or unethical, gives you lots of detailed & rich data which provides insight for further investigation
- dis: rare cases aren’t rep of pop, results are subjective & unique to individual being investigated (low reliability), don’t have control over lots of variables & diff to establish C&E
19
Q
online
A
- research that is conducted online eg: online survey
- adv: have access to a wider range of participants & less prone to interviewer bias as won’t be there to affect ps responses, may be less prone to SDB as not face 2 face with researcher
- dis: if survey is long & complicated, may give fake answers just to get rewards, psych won’t be there to probe or guide ps through qs if they misunderstand meaning
20
Q
in field
A
- done in Ps everyday environment but situations are artificially set up
- adv: more ecologically valid as done in settings that is natural to ps so more likely to reflect real life & reduced risk of DCs
- more likely to be affected by confounding & extraneous variables as aren’t controlled so may lack internal validity
21
Q
in lab
A
- conducted in artificial setting where extraneous variables are controlled
- adv: high IV as researcher has high level of control so can minimise effects of confounding Vs & more reliable as follow standardised procedure
- low ecological V as setting will be unnatural to ps so may not reflect how they would respond in a real life scenario
22
Q
longitudinal
A
- data is repeatedly gathered 4 same group over extended period of time (often weeks/months, but can be for yrs/decades)
- adv: high validity, can build up strong rapport & trust & shows changes in bev over time
- dis: increased risk of DC as over time ps more likely to guess true aim of study, takes long amount of time to collect data, issues with attrition & can be time consuming & demanding for ps & researcher
23
Q
cross sectional
A
- analyses data (eg: age, gender, occupation) from a pop at specific point in time, ps selected based on certain Vs of interest but Vs aren’t manipulated
- adv: lots of data collected quickly, reduced risk of DCs & often cheap as uses self-reports
- dis: doesn’t show bev changes over time, timing of snapshort could be unrepresentative & cohort diffs may affect result (eg: people may have diff experiences of same event based on geography)
24
Q
participant observation
A
- obs gets involved in activities of Ps they’re observing
- adv: can observe bevs in closer detail which allows them to pick up on more subtle bev & get more insight
- dis: increased risk of investigator effects, reduced objectivity as more likely to be influenced by personal feelings & opinions, diff 2 record info unobtrusively & may forget some obs when making their reports later
25
non-participant observation
* observer is NOT involved in activties of Ps, us. used in educational settings & aim is for psych to be as unobtrusive as possible
* adv: more time to record their obs as aren't involved in Ps activities & reduced risk of investigator effects as observe from a distance & sometimes aren't visible so their bev = unlikely to affect Ps bev
* dis: lack of promixity may mean they miss more subtle bevs that could provide unique insight into human bev
26
structured interview
* Qs asked in standardised order, won't probe beyond answers recieved & doesn't deviate from interview schedule
* adv: easy 2 replicate & test 4 reliability as fixed set of Qs is used
* dis: not flexible as new questions can't be asked to generate more detailed responses
27
unstructured interview
* doesn't follow rigid order, interview schedule contains open ended questions but Qs may be added or missed
* adv: flexible as can ask new questions to generate more detailed response => valid & qualitative data
* dis: harder to replicate interview as qs asked may be specific to Ps answers & requires trained interviewers so may be more expensive to employ
28
semi structured interview
* mostly prepared Qs but can ask new ones & deviate from interview schedule
* adv: (more flexible than structured) as can ask new Qs 2 get more detailed responses & fairly sensitive
* dis: flexibility may decrease reliability, ps may still lie & interviewers would still require training to know how to probe to get better answers
29
variables
DV, IV, confounding (other than IV but can be controlled - affects both IV & DV), extraneous (other than IV but can't be controlled- affects IV or DV), co-variables (Vs your investigating 2 see whether there's a rel between them)
OPERATIONALISATION - turning a subjective (& often qualitative) variable into a value that is objective & can be measured (eg: exam grades into percentage score)
30
matched pairs
* ps are split into (two) groups which are matched for certain characteristics (eg. gender & IQ), each group does one condition
* adv: ind diffs are kept constant between each condition as matched & lower risk of order effect
* dis: time consuming to match ps, more Ps needed & may not be able to match all characteristics
31
correlational study
* investigates type of rel between coVs / 2 naturally occurring Vs
* dis: doesn't establish cause & effect & can only be used when Vs can be measured on a scale
* adv: can be used when Vs can be measured but not manipulated & useful for when other methods would be impractical/ unethical
32
self reports
* data is collected directly from Ps about their thoughts, feelings & bev (possibly from spoken/written responses)
* dis: may misunderstand Qs & SDB could affect answers
* adv: high validity as collected directly from ps themsleves & can give their opinions & reasoning 4 their thoughts which provides more insight
33
quasi experiment
* has all features of lab except random allocation
* adv: may have higher EV as researcher is less involved, higher realism as measures how IV naturally affects DV & can be used in situations where it would be impractical to manipulate IV (eg: Raine)
* dis: can only be used in sits where IV is naturally occuring may still have low eco validity if in controlled settings, not establish cause & effect & be more affected by extraneous Vs
34
internal & external reliability
INTERNAL - extent to which a measure is consistent within itself (can assess using split half)
EXTERNAL - extent to which a measure varies from one use to another (can use test-retest or inter-rater if it can't be repeated) OR two measures of same thing are consistent when compared (can be increased using a standardised procedure)
35
internal & external validity
INTERNAL - measure of whether results obtained are solely affected by changes in IV in cause & effect rel (& not due to any other variable)
EXTERNAL - measure of whether findings can be generalised to situations other than what the findings were gathered in
36
repeated measures
* all participants do the same/ all the conditions
* adv: fewer Ps needed & reduced effect of P diffs as same Ps used for both conditions
* dis: order effect due to fatigue/boredom, time consuming as have to wait for all Ps to do condition before you can move on to next one & increased risk of DCs as have more time to figure out psych's aim
37
independent groups
* ps divided into (two) groups & each group does 1 condition
* adv: reduced risk of order effect & DC (as less likely to gain enough info to guess aim) & maybe less T.C
* dis: ind diffs have greater effect (as have more than one group/ Ps are doing diff conditions) & more Ps needed (so may be more time consuming ??)
38
quantative data
* numerical data that can be statistically analysed
* adv: objective, allows for direct comparison, can be collected quickly from a large pop & simple
* dis: doesn't provide a lot of detail or meaning & lacks validity
39
brain scans general strengths & weaknesses
* allows you to investigate the structure and activity of the live brain
* allows for objective assessment of brain
* us really expensive & not easily accessible for research
* limit to what you can investigate as person of us. stuck in a machine (eg: can’t investigate brain activity whilst they’re running
