Science of Psych Midterm 1

Empiricism

The belief that accurate knowledge can be acquired through observation

Scientific Method

A procedure for using empirical evidence to establish facts and determine if an idea is true.

Theory

An explanation of a natural phenomenon that makes specific predictions about what we should observe in the world.

Hypothesis

A falsifiable prediction made by a theory.

Empirical method

A set of rules and techniques for observation.

Complexity of People

Humans are difficult to study because their brains and behaviors are incredibly intricate.

Variability of People

No two humans ever do, say, think, or feel exactly the same thing under the same circumstances.

Reactivity of People

People tend to think, feel, and act differently when they are being observed.

Measurement

Defining the property you want to measure and finding a way to detect it.

Operational definition

A description of a property in measurable terms.

Construct validity

The extent to which the thing being measured adequately characterizes the property you want to assess.

Power

A detector's ability to detect the presence of differences or changes in the magnitude of a property.

Reliability

A detector's ability to detect the absence of differences or changes in the magnitude of a property (consistency).

Demand characteristics

Aspects of an observational setting that cause people to behave as they think someone else wants or expects.

Naturalistic observation

A technique for gathering scientific information by unobtrusively observing people in their natural environments.

Observer bias

The tendency for observers' expectations to influence both what they believe they observed and what they actually observed.

Double-blind study

A study in which neither the researcher nor the participant knows how the participants are expected to behave.

Variable

A property that can take on different values.

Correlation

Occurs when variations in the value of one variable are synchronized with variations in the value of the other.

Positive correlation

A "more-is-more" relationship where two variables move in the same direction.

Negative correlation

A "less-is-more" relationship where two variables move in opposite directions.

Natural correlations

Correlations we observe in the world around us that cannot tell us why variables are related.

Third-Variable Problem

The fact that a natural correlation between two variables cannot be taken as evidence of a causal relationship because an outside variable might be causing them both.

Experimentation

A technique for determining whether there is a causal relationship between variables.

Manipulation

Changing a variable in an experiment to isolate a specific cause and effect.

Independent variable

The variable that is manipulated in an experiment, determined entirely by the experimenter.

Dependent variable

The outcome variable that is measured in an experiment, which depends on the participants.

Self-selection

A problem that occurs when anything about a participant determines their condition in an experiment.

Random Assignment

A procedure that assigns participants to an experimental or control condition by chance.

Internal validity

An attribute of an experiment that allows it to establish causal relationships (everything inside the study works as it should).

External validity

An attribute of an experiment in which variables have been operationally defined in a normal, typical, or realistic way (ability to generalize).

Population

A complete collection of people.

Sample

A partial collection of people drawn from a population.

Case method (Case Study)

A procedure for gathering scientific information by studying a single individual in depth.

Random sampling

A technique for selecting participants that ensures every member of a population has an equal chance of being included.

Replication

An experiment that uses the same procedures as a previous experiment but with a new sample from the same population.

Dual Representation

Seeing something in its structure but understanding it represents something else (e.g., DeLoache's Snoopy room study).

Self-report Measures

Assessments that ask people directly about their own characteristics, opinions, and attitudes.

Response sets

Distorting answers on a survey to feel more desirable.

Halo & Horns Effect

Letting our personal opinions about things interfere with our objective evaluation of others.

Convenience selection

Sampling participants who are readily available rather than randomly selecting from the whole population.

Placebo Effect

Improvement resulting from mere expectation of a treatment.

Experimenter Expectancy Effect

When a researcher's hypotheses lead them to unintentionally bias the study outcome.

Normal distribution

A bell curve where 95% of data is captured within plus or minus 2 standard deviations.

Negative skew

A data distribution with an elongated tail pointing left.

Positive skew

A data distribution with an elongated tail pointing right.

Mean

The statistical average.

Median

The middle value in a set of data.

Mode

The value that occurs most frequently in a dataset.

Range

The distance between the highest and lowest value.

Standard Deviation

The average distance of scores from the mean.

Descriptive Statistics

Statistics used to organize, summarize, simplify, describe, and present data.

Inferential Statistics

Statistics used to generalize from samples to populations, test hypotheses, and make predictions.

Congruency bias

The tendency to consider evidence we can see and forget about the missing evidence we cannot see.

Informed Consent

The ethical requirement that participants agree to a study after learning what it entails.

Freedom from Coercion

The ethical principle that subjects cannot be pressured or forced into participating.

Protection from Harm

The obligation to take every possible precaution to protect participants physically and psychologically.

Risk-benefit analysis

The ethical requirement that participants cannot be asked to accept large risks without proportionate scientific value.

Deception

Used only when necessary, requiring researchers to mislead participants about a study's true purpose.

Debriefing

Explaining to the participant what the study was actually about and what deception was used after the study concludes.

Confidentiality

The ethical obligation to keep all participant information private.

Correlation coefficient (r)

A statistical measure of both the direction and strength of a correlation.

Statistical Significance

A mathematical indication that research results are not likely due to chance.

Practical Significance

A finding that has a real-world impact or meaningful application.

Type I Error

A false alarm

Type II Error

A missed detection (false negative)

Illusory Correlations

Seeing a relationship between variables that does not actually exist.

Institutional Review Board (IRB)

A committee that reviews and ensures research studies follow ethical guidelines.

Open Science

Actions designed to make scientific processes more transparent and results more accessible to build a robust science.

Cell Body

The largest component of the neuron that coordinates information-processing tasks and keeps the cell alive.

Dendrites

Tree-like parts of the neuron that receive information from other neurons and relay it to the cell body.

Axon

The long part of the neuron that carries information to other neurons, muscles, or glands.

Myelin Sheath

An insulating layer of fatty material that speeds up communication between cells.

Glial Cells

Support cells found in the nervous system that protect neurons, create myelin, and form the blood-brain barrier.

Synapse

The junction or space between the axon of one neuron and the dendrites or cell body of another.

Sensory neurons (unipolar)

Neurons that receive information from the external world and convey it to the brain via the spinal cord.

Motor neurons (multipolar)

Neurons that carry signals from the spinal cord to the muscles to produce movement.

Interneurons (multipolar)

Neurons that connect sensory neurons, motor neurons, or other interneurons.

Purkinje cells

A type of interneuron that carries information from the cerebellum to the rest of the brain and spinal cord.

Pyramidal cells

Neurons in the cerebral cortex with a triangular cell body and a single, long dendrite.

Resting potential

The difference in electric charge between the inside (negative) and outside of a neuron's cell membrane at rest.

Action potential

An electric signal that is conducted along the length of a neuron's axon to a synapse.

Terminal buttons

Knoblike structures that branch out from the end of an axon to release chemicals.

Neurotransmitters

Chemical messengers that transmit information across the synapse to a receiving neuron's dendrites.

Receptors

Parts of the cell membrane that receive neurotransmitters and initiate or prevent a new electric signal.

Reuptake

A process moving a neurotransmitter from the synapse back into the axon terminal from which it was released.

Acetylcholine (ACh)

A neurotransmitter involved in voluntary motor control.

Dopamine

A neurotransmitter regulating motor behavior, motivation, pleasure, and emotional arousal.

Glutamate

The major excitatory neurotransmitter in the brain that enhances the transmission of information.

GABA

The primary inhibitory neurotransmitter in the brain that stops cells from firing.

Norepinephrine

A neurotransmitter involved in states of vigilance or heightened awareness of dangers.

Serotonin

A neurotransmitter regulating sleep, wakefulness, eating, and aggressive behavior.

Endorphins

Chemicals that act within the pain pathways and emotion centers of the brain.

Agonists

Drugs that increase or mimic the action of a neurotransmitter.

Antagonists

Drugs that block or diminish the function of a neurotransmitter.

Central nervous system (CNS)

The system composed of the brain and spinal cord.

Peripheral nervous system (PNS)

The system connecting the central nervous system to the body's organs and muscles.

Somatic nervous system

The set of nerves that conveys information between skeletal muscles and the central nervous system.

Autonomic nervous system (ANS)

The set of nerves carrying involuntary commands that control blood vessels, body organs, and glands.

Sympathetic nervous system

The set of nerves that prepares the body for action in challenging or threatening situations (fight or flight).