Research methods

CAT scan

CAT scan

Computerised Axial Tomography

Used to detects physical abnormalities e.g. tumours, strokes.

Scanner rotates 180˚and multiple x rays are taken. (takes pictures at each and every angle).Computer then uses the images to create a cross sectional picture of the brain.

EEG

Electroencephalogram

Measures brain frequency(brain waves per second)

Judged by peaks and troughs (amplitude and depth)

Used to detect and investigate epilepsy, states of consciousness and arousal.

MRI

Magnetic Reasoning Imaging

Uses strong magnetic, radio frequency pulses and computers to produce its imaging

Complies thousands of its images to create a 3d picture of the brain

FRMI

Functional MRI

Form of dynamic imaging

Used to measure activity in the brain when neurons are consuming oxygen

A higher BOLD (Blood Oxygenated Level Dependant) singal means increased oxygen levels

When a brain area is more active it consumes more oxygen

Operational hypothesis

Must include

1. population

2. independant and dependant variable (must have both, operationalise them (how each variable will be measured))

3. predicted direction

4. measurement tool

controlled vairable

The variable that is constant, does not change

correlation

A statistic that measures the degree to which 2 variables move in relation to each other

dependant variable

The variable that is measured. Dependant on the independent variable

independent variable

variable manipulated by the experimentor

mean

central tendency, calculated by adding all the scores in a data set, divided by the total number of scores

median

a measure of central tendency, calculated by arranging scores in a data set from highest to lowest, then find middle number.

mode

A measure of central tendency that shows the most frequently occurring score in a data set

non experimental

Research that lacks the manipulation variables

Usually qualitative data (information not expressed in numbers)

uses observational

• longitudinal research, correlational study and cross-sections

some non-experimental research is:

• Interviews

• Focus groups

• Content analysis

• Case study research

experimental

Scientific or experimental research uses a scientific approach to manipulate one variable and measure the effect on the subject

identify cause and effect relationships

Can be measured by:

• Heart rate monitor,

• EEG measure brain waves

• Breathing rate

• Not open to interpretation

  or

Subjective measures

• Checklists

• Rating scale (self-report)

• Open to interpretation

Quantitative data

Numerical data e.g. heart rate, respiratory rate

Longitudinal research

Research that follows the development of one group of people over time to make claims about developmental changes

Correlational study

Researchers investigate if there is a relationship between the variables, without researcher controlling or manipulating them

3 outcomes

1. a positive correlation (the x and y axis both increase)

2. negative correlation (x or y axis is decreasing)

3. no relationship (no pattern)

Experimental group

Groups that is exposed to the treatment

The IV is present

Qualitative data

Descriptive, relating to words and language.

e.g. open ended surveys, interviews.

Most commonly used in non experimental

Placebo effect

A change in a participants behaviour because they believe they have been exposed to a treatment

Participants should not know what group they’re in (control or experimental) to present this.

→ can be done using a placebo e.g. sugar pill

Extraneous variable

AKA controlled variable

Variable must be kept in control to prevent inaccurate conclusions

causes changes to DV

Any variable except independant that could potentially affect outcome of your research study

sample

a group of participants selected from a population of research interest

Protection of participants

Researchers must ensure those taking part in research will not be caused distress

You must not embarrass, frighten, offend or harm participants

Researchers must ensure vulnerable groups ( elderly, disabled, children) receive special care

informed consent

Before the study begins the researcher must outline to the participant what the research is about, then ask for their consent

• An 18+ years can provide consent

• Parents/legal guardians of minors must provide consent

Voluntary participation

Ensures a participant willingly decided to take part in an experiment

Right to discontinue at anytime

Participants must not experience any pressure or coercion to participate, nor be threatened with any negative consequences if they decide not to participate in the experiment

withdrawal rights

The right of the participants to cease their participation in a study at any time without negative consequences or pressure to continue

Must be adhered to during an experiment and after an experiment

confidentiality

Participants and the data gained from them must be kept private unless they give their full consent

All identifying information must be removed from the research report

anonymity

Means you don’t know who the participant are

Deception

This is when participants are misled, wrongly informed or not told all the time information about the aims of the research or the method of the experiment

Researcher should avoid deception, unless there is not alternative. Then the experiment would need to be judged acceptable by an independent expert

Sometimes deception is necessary in order to avoid demand characteristics (when the participant behaves in the way they know the researcher is looking for)

Debrief

After the research is over the participant should be able to discuss the procedure and finding with the psychologist

They should be told if they have been deceived and why. They must be given an idea what the researcher was investigating and their part in the research explained

Reliability

An examination of how consistent the result of an assessment are. Do you get the same results each time you do the assessment?

Validity

Refers to how well a test actually measures what it was created to measure

Correlation coefficient

A number that measures the relative strength of the linear relationship between two variables (R value)

• The closer to 1, the stronger the positive linear relationship.

• The closer to the -1, the stronger the negative linear relationship

P value

Evaluates how well your data rejects the null hypothesis (no relationship between two compared groups)

• If P value is low, the probability of the correlation occurring by chance is small

• If P value is less than 0.05 then the results are acceptable

• If P value is more than 0.05 then researcher would reject the hypothesis

Code of ethics

A set of principles and guidelines that outline the ethical regulations and values that individuals or organizations must abide by

Convenience sampling

Participants selected based on their availability

cross sectional study

gather data from a sample at a specific point in time, allows researcher to compare different groups

generalisation

the extent to which findings can be applied to the population

null hypothesis

predicted the IV would have no effect

Random sampling

every member of the population has an equal chance of being selected for the sample

Representative sample

key characteristics of the sample closely resembles the key characteristics of the population

scattergram (scatter plot)

shows values of two behavioural variables for each participant in the sample DON’T JOIN DOTS

Stratified sampling

selecting a sample from the population in a way that results in subgroups being represented in the same proportions as they are in the population

Snow ball sampling

Participants are recruited through referrals from other participants