Psychology I – Complete Master Review: Scientific Method, Biological Psychology, Sensation & Perception, and More

Introducing Psychological Science

The Scientific Method in Psychology

Psychology is the scientific study of behavior and mental processes. The scientific method is a systematic approach used to investigate phenomena, acquire new knowledge, or correct and integrate previous knowledge.

• Steps: Theory, hypothesis, test hypothesis (reject or confirm), revise theory, confirm hypothesis, generate new hypothesis.

• Hypothesis: A testable prediction about processes that can be observed and measured.

• Falsifiability: Hypotheses must be precise enough to be disproven.

• Replication: The process of repeating a study and finding a similar outcome each time.

• Critical Thinking: Involves curiosity, skepticism, and evaluating evidence objectively.

Example: Testing whether sleep improves memory by comparing test scores of sleep-deprived and well-rested participants.

Reading and Evaluating Scientific Research

Variables and Operational Definitions

Variables are objects, concepts, or events being controlled, manipulated, or measured by a scientist. Operational definitions specify the procedures or operations used to measure variables.

• Independent Variable (IV): Manipulated by the experimenter.

• Dependent Variable (DV): Measured outcome affected by the IV.

• Confounding Variable: A variable outside of the researchers' control that might affect or provide an alternative explanation for the results.

Research Designs

• Random Assignment: Technique for dividing samples into groups to ensure equal likelihood of placement in any condition.

• Single-Blind Study: Participants do not know the true purpose or treatment.

• Double-Blind Study: Neither participants nor experimenters know the treatment allocation.

• Case Study: In-depth report about the details of a specific case.

• Naturalistic Observation: Unobtrusive observation of behavior as it occurs in the natural environment.

• Surveys: Questionnaires used to gather information about behavior, attitudes, and beliefs.

Ethical Considerations

• Confidentiality: Results are seen only by the researcher.

• Deception: Sometimes necessary, but must be explained during debriefing.

• Debriefing: Explaining the true nature of the study after participation.

Descriptive Statistics: Frequency and Distributions

Frequency and Distributions

Descriptive statistics summarize and organize data.

• Frequency: How often a score occurs.

• Distribution: Arrangement of scores; can be normal or skewed.

Central Tendency

• Mean: Arithmetic average.

• Median: Middle score.

• Mode: Most frequent score.

Inferential Statistics and Hypothesis Testing

• Inferential Statistics: Used to determine whether results are likely due to chance.

• Statistical Significance: Commonly defined as $p < 0.05$.

Biological Psychology

The Nervous System

The nervous system is a complex network of neurons that conveys electrochemical information throughout the body.

• Central Nervous System (CNS): Brain and spinal cord.

• Peripheral Nervous System (PNS): Nerves outside the CNS.

• Somatic Nervous System: Controls voluntary movement.

• Autonomic Nervous System: Controls involuntary functions; subdivided into sympathetic (arousal) and parasympathetic (rest and digest) divisions.

Neurons and Neural Communication

• Neurons: Specialized cells that communicate via electrochemical signals.

• Glial Cells: Support, nourish, and protect neurons.

• Action Potential: Rapid change in voltage within a neuron, the basis for neural signaling.

• Synapse: Gap between neurons where neurotransmitters are released.

Equation: Resting potential of a neuron: $-70 \text{ mV}$

Neurotransmission and Drug Effects

• Neurotransmitters: Chemical messengers (e.g., dopamine, serotonin).

• Agonists: Drugs that increase neurotransmitter activity.

• Antagonists: Drugs that decrease neurotransmitter activity.

Sensation and Perception

Basic Concepts

• Sensation: Detecting external events with sense organs and turning those events into neural signals.

• Perception: Involves attending to, organizing, and interpreting stimuli.

Types of Sensory Receptors

• Vision: Light waves detected by photoreceptors in the retina.

• Hearing: Sound waves detected by hair cells in the cochlea.

• Taste: Chemicals detected by taste buds.

• Smell: Chemicals detected by olfactory receptors.

• Touch: Pressure, temperature, pain detected by skin receptors.

Perceptual Processes

• Bottom-up Processing: Perceiving bits of sensory information and constructing a complex perception.

• Top-down Processing: Expectations and prior knowledge influence perception.

• Signal Detection Theory: Whether a stimulus is perceived depends on both sensory input and decision criteria.

Gestalt Principles

• Figure and Ground

• Proximity

• Similarity

• Continuity

• Closure

Example: Recognizing a friend in a crowded room by using prior knowledge and expectations.

Genetics and Behavior

Basic Genetic Concepts

• Genes: Biological units of heredity passed from parents to offspring.

• Chromosomes: Structures that organize and package DNA; humans have 23 pairs.

• Genotype: The complete genetic makeup of an organism.

• Phenotype: Observable characteristics resulting from gene and environment interaction.

• Heritability: How much variation in phenotype across people is due to differences in genotype.

Evolutionary Psychology

Natural Selection and Behavior

Evolutionary psychology explains behavior in terms of natural selection. Traits that provide a survival or reproductive advantage are more likely to be passed on.

• Adaptations: Psychological traits may persist because they were adaptive for ancestral environments.

Brain Research Methods

Methods for Studying the Brain

• Lesion Studies: Examining brain damage and its effects.

• Animal Research: Studying brain activity in non-human animals.

• Neuroimaging: Using technology to observe brain activity and structure.

Example: Using fMRI to study which brain areas are active during memory tasks.

Additional info:

• Some context and definitions have been expanded for clarity and completeness.

• Tables and equations have been described in text or LaTeX format as appropriate.