Methods of studying human diversity

Lecture 2

Self-report measures

Presenting a list of statements and asking participants the extent to which they agree/ disagree with them,

Advantages of self-report

Low-cost and easy to administer on a large scale.

Disadvantages of self-report measures

• social desirable answers

• acquiescene bias

• requires introspection

• only measures thoughts and self-perception

Experience sampling method

Asking participants to report their thoughts, feelings and behaviours repeatedly over a certain period of time.

Potential problem with experience sampling

Self-monitoring can influence what is being measured

Observational measures

Typically involves recording what is being done or how often something is done through observation by a third person.

Advantage of observational measures

Can be used when it is impossible/ inappropriate to give instructions to a participant.

Potential issues with observational measures

• can only measure overt behaviours

• scoring may be influenced by observer biases

Performance measures

Measures include intelligence, reading/ math performance, ect. Accuracy is measured by error rates, percent correct, or percentiles.

What do performance measures show?

Differences between people show different ability levels. Differences between tasks show different ways of processing information.

Advantage of perfomance measures

Results are objective

Potential problems of performance measures

Low ecological validity

Skin conductance response (SCR)

Reflects sympathetic arousal (emotional, physiological).

Electromygraphy (EMG)

Measures muscle activity, used to study facial expression mimicry and emotional reactions

Masked priming task

The word prime is expected to shorten reaction time to naming of the picture, and vice versa.

Priming paradigm

Participants are exposed to a certain stimulus, and their response to a subsequent stimulus is measured.

Masked priming

The prime is presented followed by a junk visual material (mask), preventing the prime from entering conscious processing.

Factor analysis

A statistical technique used to reduce a large number of variables into fewer 'factors; looks at how different variables change together (covary).

Magnetic resonance imaging (MRI)

Brain imaging technique used to measure brain volume, grey matter white matter ect; different types of tissue produce different signals.

functional Magnetic Resonance Imaging (fMRI)

Tracks changes in blood flow and oxygen use during mental tasks

PET scan

Uses radioactive tracer to measure brain activity by detecting radioactivity in each voxel.

Key advantages of fMRI over PET

• better temporal resolution

• better spatial resolution

Functional specialisation

Where brain activity happens

Functional integration

How brain regions interact

Network analysis

Looks at functional connectivity

Diffusion Tensor Imaging (DTI)

Maps white matter tracts to show structural brain networks.

Single-cell recording

Invasive, measures action potentials in individual neurons

EEG/ ERP

Measures electrical brain activity and responses to stimuli; links timing of brain activity to cognitive processes.

Evaluation of EEG

Good temporal resolution, but poor spatial resolution.

Magnetoencephalography (MEG)

Records magnetic fields from braid activity.

MEG evaluation

Excellent temporal and better spatial resolution than EEG but very expensive.

Lesion studies

Examine behavioural deficits after brain damage

Brain stimulation

TMS and tDCS can temporarily disrupt or enhance neural activity

Phenotype

Outward traits like appearance and personality.

Behavioural genetics

Studies gene-environment behaviour links through family, twin, and adoption studies/

Unpacking studies

Identify individual-level variables explaining cross-cultural differences