Psychology: Key Concepts in Research Methods and Neurotransmitters

Hypothesis

Tentative explanation - must be FALSIFIABLE - able to be supported or rejected

Operational Definition

Clear, precise, quantifiable definition of your variables - allows replication and collection of reliable data

Qualitative data

Descriptive data (eye color)

Quantitative data

Numerical data - IDEAL and necessary for statistics

Population

Everyone the research could apply to

Sample

The people (or person) specifically chosen for your study

Advantage of Correlation

Useful when experiments are unethical

Disadvantage of Correlation

CORRELATION DOES NOT EQUAL CAUSATION

Directionality problem

Which direction does the correlation go?

3rd variable problem

Different variable is responsible for relationship

Positive Correlation

Variables increase & decrease together

Negative Correlation

As one variable increases the other decreases

Independent Variable

Purposefully altered by researcher to look for effect

Experimental Group

Received the treatment (part of the IV)

Control Group

Placebo, baseline (part of the IV); can only have 1

Dependent Variable

Measured variable (is DEPENDENT on the independent variable)

Placebo Effect

Any observed effect on a behavior that is 'caused' by the placebo

Double-Blind

Experiment where neither the participant nor the experimenter are aware of which condition people are assigned to

Single-Blind

Only participant blind - used if experimenter can't be blind

Confound

Error/flaw in study that is accidentally introduced

Random Assignment

Assigns participants to either control or experimental group at random

Naturalistic Observation

Observe people in their natural settings

Case Study

Studies ONE person in great detail

Meta-Analysis

Combines multiple studies to increase sample size and examine effect sizes

Descriptive Statistics

Show shape of the data

Mean

Average (use in normal distribution)

Median

Middle number (use in skewed distribution)

Mode

Occurs most often

Range

Distance between smallest and biggest number

Standard Deviation

Average amount the scores are spread from the mean

Inferential Statistics

Establishes significance (meaningfulness)

Statistical Significance

Results not due to chance, experimental manipulation caused the difference in means

Ethical Guidelines

IRB approval needed for people

Confidentiality

Names kept secret

Informed Consent

Must agree to be part of the study

Debriefing

Must be told the true purpose of the study

Endorphins

Decrease pain

Substance P

Pain regulation (abnormality increases pain and inflammation)

Hormones

If not in the nervous system, it's a hormone

Oxytocin

Love, bonding, childbirth, lactation

Adrenaline

Fight/flight

Leptin

Makes you full (stops hunger)

Ghrelin

Makes you hungry (turns you into a gremlin)

Melatonin

Sleep

Agonist

Drug that mimics a neurotransmitter

Antagonist

Drug that blocks a neurotransmitter

Reuptake

Unused neurotransmitters are taken back up into the sending neuron

Depressants

Decrease nervous system activity (e.g., alcohol)

Stimulants

Increase nervous system activity (e.g., caffeine & cocaine)

Hallucinogens

Hallucinations and altered perceptions (e.g., marijuana)

Opioids

Relieve pain (endorphin agonists) (e.g., heroin)

Tolerance

Needing more of a drug to achieve the same effects

Addiction

Must have it to avoid withdrawal symptoms

Withdrawal

Symptoms associated with sudden stoppage

Cerebellum

Movement, balance, coordination, procedural memory

Brainstem / Medulla

Vital organs (heart rate, blood pressure, breathing)

Reticular activating system

Alertness, arousal, sleep, eye movement

Cerebral Cortex

Outer portion of the brain - higher order thought processes

Amygdala

Emotions, fear

Hippocampus

Episodic and semantic memory

Hypothalamus

Reward/pleasure center, eating behaviors

Thalamus

Relay center for all but smell

Pituitary gland

Talks with endocrine system and hypothalamus - release hormones

Broca's Area

Inability to produce speech

Wernicke's Area

Can't comprehend speech

Corpus Callosum

Bundle of nerves that connects the two hemispheres

Brain Plasticity

Brain changes via damage and through experience

EEG

Shows broad brain activity - not specific - electrical output

fMRI

Shows brain activity in specific regions, measures oxygen

Lesion

Destruction of brain tissue

Pain

Both mental and physical

Hot

Activation of warm and cold receptors

Taste (gustation)

6 taste receptors: bitter, salty, sweet, sour, umami (savory), oleogustus (fatty/oily)

Taste processing

Tongue, mouth, and brain process taste

Super tasters

Density of taste receptors makes people super tasters, medium tasters, or nontasters

Sensory interaction

Creates taste - without smell, taste isn't as strong or is absent

Smell (olfaction)

Only sense that does NOT route through the thalamus

Pheromones

Produce chemical signals within a species for attraction

Top-Down Processing

Whole idea (prior expectations) to smaller parts (painting with faces)

Bottom-Up Processing

Smaller parts (sensory info) to whole idea (dog of bunch of dots)

Schemas

Preexisting mental concept of how something should look (like a restaurant)

Perceptual Set

Tendency to see something as part of a group - speeds up signal processing

Gestalt Psychology

Whole is greater than the sum of its parts

Figure/ground

Organize information into figures (objects) that stand apart from surroundings (background)

Closure

Mentally fill in gaps

Proximity

Group things together that appear near each other

Similarity

Group things together based off of looks

Constancies

Recognize that objects do not physically change despite changes in sensory input (size, shape, brightness)

Apparent Movement

Objects can appear moving when they aren't (flip books, blinking lights)

Selective attention

Focus on one thing and block out other things

Inattentional Blindness

Failure to notice something added because you're so focused on another task

Change Blindness

Fail to notice a change in the scene

Cocktail party effect

Notice your name across the room when it's spoken, when you weren't previously paying attention

Binocular Depth Cues

How both eyes make up a 3D image

Retinal Disparity

Image is cast slightly different on each retina, location of image helps us determine depth

Convergence

Eyes strain more (looking inward) as objects draw nearer

Monocular Depth Cues

How we form a 3D image from a 2D image

Interposition

Overlapping images appear closer

Relative Size

2 objects that are usually similar in size, the smaller one is further away

Linear Perspective

Parallel lines converge with distance (think railroad tracks)