measuring people Flashcards
How do you define reaction time
stimulis (perception) - reaction time (processing) - produce response (response)
the time it takes to respond to a particular stimulus
Why is reaction time commonly used as DV within psychology?
provides an indirect measure of mental processes.
specially, nature of process and how different stimuli effects processes
What is a simple reaction time
1 type of stimulus and 1 type of response
What is choice reaction time
more than 1 stimulus and each has it’s own specific response
What is discriminant reaction time
more than one stimulus, but only one response is required
What can be used to measure brain activity
PET - positron emission tomography
fMRI - functional magnetic resonance imaging
TMS - transcranial magnetic stimulation
EEG - electroencephalography
How does a PET measure brain activity?
radioactive substance injected into participants
active cells take up radioactive substance more readily
PET able to produce scan of brain - different colours represent the different levels of radioactivity
Relatively high spatial resolution
Poor temporal resolution
How does fMRI measure brain activity?
active brain regions require more oxygen
oxygenated blood produces different signal to deoxygenated blood
Signals are used to created high spatial resolution image of brain
Relatively high spatial resolution
Poor temporal resolution
How does TMS measure brain activity
magnetic field applied to scalp stopping neurons which are directly below
turning off brain areas can provide understanding of their involvement in tasks
How does EEG measure brain activity
used as a way to measure brains electrical activity
electrodes attached to scalp which detect small changes in voltage
Different waveforms produced reflect different functional states of the brain
Excellent temporal resolution
Poor spatial resolution
What can psychological tests be used for?
A number of things, for example:
Happiness, sleep, anxiety. depression…
What are some issues which can arise using questionnaires / psychological tests?
Response bias
Acquiescence bias -tendency to respond positively to all items
Response bias - tendency to give the same response to all items.
