allows designing interventions to fix the causal-effect (with other hypotheses /predictions)
General scope: need to apply across a variety of different settings
How reliable is research?
Construct validity: Am i measuring the right construct?
makes sure that events that occur in research setting actually correspond to the theoretical construct
The extent to which the independent and dependent variables used in research correspond to the theoretical constructs under investigation
IVs and DVs must correspond to the intended constructs, and they must not correspond to other constructs
There are infinitely many ways to measure psychological constructs
How to measure psychological constructs:
self-report measures: rate on a scale
observational measure: record actions
archival measures: see past trends
performance measure: test scores/speed/…
physiological measure: brain activity
Internal validity: can i draw the correct conclusions about causality?
extent to which it can be concluded that changes in the independent variable actually caused changes (not any other cause) in the dependent variable in a research study
dependent on the research design
Gold standard of establishing causality is an experimental design:
A research design in which researchers randomly assign participants to different groups and manipulate one or more independent variables.
Random assignment: The procedure of assigning participants to different experimental groups so that every participant has exactly the same chance as every other participant of being in any given group.
Manipulation: Intentionally varying some factor as the independent variable in an experimental research design
External validity: makes sure that we can make claims about more than just the people in a study (generalize)
extent to which research results can be generalized to other appropriate people, times, and settings
Biological psychology:
The human nervous system
Includes:
peripheral nervous system (PNS)
somatic nervous system: control what brain ask of the body
cranial nerves: Emerge directly from the brain
spinal nerves: Emerge from the segments of the spinal cord.
autonomic nervous system
parasympathetic nervous system: The “rest-and-digest” system, conserving energy and promoting routine body maintenance
sympathetic nervous system: The “fight-or-flight” system, preparing the body for intense physical activity or perceived danger.
central nervous system (CNS):
Stress
Three dimensions of stress:
Psychological stress
Sympathetic nervous system reaction to stress
Hormonal reaction to stress
Psychological stress response
Psychological stress = perceived stress
appraisal theory:
Our emotional and physiological response to an event is not determined by the event itself, but by our interpretation or appraisal of it
Stress is a transaction between an individual and their environment
Step 1: Primary Appraisal: interpretation of the stressors → if dangerous → step 2
Initial evaluation
“Am I in trouble?”
Three possible outcomes:
Irrelevant
Benign–positive
Stressful
Three stressful appraisal forms:
Harm/loss (damage already sustained)
Threat (anticipated harm/loss)
Challenge (possibility for mastery or gain)
Step 2: Secondary Appraisal: analysis of the available resources
“What might and can I do?” → if efficient → cause stress
Different coping options are evaluated:
Will it accomplish what it is supposed to do?
Can I apply a particular strategy effectively?
What are the consequences of using that strategy?
Step3: Reappraisal: pacing and learning
“How has the situation changed?”
Usually based on new information or as a result of cognitive coping efforts
Sympathetic nervous system reaction to stress
Increase quickly and dropping quickly right after
Neurons and neural activity:
Neurons communicate using electrical signals (action potentials)
Action potentials form the basis of all neuronal communication
At the macro level, the firing rate reflects transmission of information
Even during sleep, there is only a small, ~15%, decrease in energy use
Energy to the brain is supplied as oxygen and glucose (sugar)
How to measure neural activity? with subtraction method
Most common use of fMRI is to apply the subtraction method to identify brain areas related to certain cognitive functions
Example use:
Why do people remember some words but not others?
Participants learned lists of words
Needed to make recognition decisions
Measure activity for remembered vs. forgotten words
subtraction method: minus the 2 scans to identify the differences
Connectivity analysis
Measurement of neural activity asks which areas are active when engaging with a specific task
Connectivity analysis asks which areas influence the activity of other areas
