AP Psychology Unit 1: Biological Bases of Behavior in Psychology

Heredity

The genetic transmission of characteristics from parents to offspring.

Environment

The external factors and conditions that influence behavior and mental processes.

Evolutionary Perspective

A viewpoint that explains psychological traits as adaptations that have evolved over time.

Behavior Genetics

The study of the relative power and limits of genetic and environmental influences on behavior.

Mutations

Changes in the DNA sequence that can lead to variations in traits.

Genes

Segments of DNA that contain the instructions for building proteins, which influence traits.

Genome

The complete set of genes or genetic material present in a cell or organism.

Eugenics

The study of or belief in the possibility of improving the human race by selective breeding.

Identical (Monozygotic) Twins

Twins that develop from a single fertilized egg that splits into two embryos.

Fraternal (Dizygotic) Twins

Twins that develop from two separate fertilized eggs.

Sympathetic Nervous System

The part of the autonomic nervous system that prepares the body for stressful or emergency situations.

Central Nervous System

The part of the nervous system consisting of the brain and spinal cord.

Peripheral Nervous System

The part of the nervous system that connects the central nervous system to the rest of the body.

Neurons

The basic building blocks of the nervous system that transmit information through electrical and chemical signals.

Action Potential

A neural impulse that travels down an axon, triggered by a change in electrical charge.

Neurotransmitters

Chemical messengers that transmit signals across a synapse from one neuron to another.

Refractory Period

The time following an action potential during which a neuron is unable to fire again.

Resting Potential

The electrical charge of a neuron when it is not actively firing.

Depolarization

The process during the action potential when the cell membrane becomes more positive.

Excitatory Neurotransmitters

Neurotransmitters that increase the likelihood of a neuron firing an action potential.

Inhibitory Neurotransmitters

Neurotransmitters that decrease the likelihood of a neuron firing an action potential.

Psychoactive Drugs

Substances that affect the brain and alter consciousness, mood, perception, and behavior.

Psychoactive Drugs

Substances that alter perception, mood, or consciousness.

Substance Use Disorder

A condition characterized by an individual's inability to control their use of a substance despite negative consequences.

Antagonist

A substance that blocks or dampens the biological response of a receptor.

Stimulants

Drugs that increase alertness, attention, and energy.

Caffeine

A common stimulant found in coffee and tea that increases alertness.

Cocaine

A powerful stimulant drug derived from coca leaves that increases energy and euphoria.

Methamphetamines

Highly addictive stimulants that affect the central nervous system.

Ecstasy

A synthetic drug that alters mood and perception, often used recreationally.

Opioids

A class of drugs that include prescription pain relievers and illegal drugs like heroin.

Heroin

An illegal opioid that produces intense euphoria and is highly addictive.

Addiction

A chronic condition characterized by compulsive drug seeking and use despite harmful consequences.

Agonist

A substance that activates a receptor to produce a biological response.

Reuptake Inhibitor

A drug that prevents the reabsorption of neurotransmitters, increasing their availability in the synaptic cleft.

Depressants

Substances that reduce neural activity and slow body functions.

Barbiturates

A class of drugs that act as central nervous system depressants.

Alcohol

A depressant that affects the central nervous system and impairs cognitive functions.

Hallucinogens

Substances that cause perceptual anomalies and alter thoughts and feelings.

Near-Death Experience

A profound psychological event with reported experiences of detachment from the body.

Marijuana

A psychoactive drug derived from the Cannabis plant, often used for recreational or medicinal purposes.

LSD

A powerful hallucinogenic drug that alters perception and mood.

Tolerance

A reduced response to a drug after repeated use, requiring higher doses to achieve the same effect.

Withdrawal

Symptoms that occur when a person reduces or stops the intake of a substance they are dependent on.

Biological Psychology

The study of the relationship between biological processes and psychological phenomena.

Biopsychosocial Approach

An integrative model that incorporates biological, psychological, and social factors in understanding health and illness.

Levels of Analysis

Different perspectives used to understand a phenomenon, including biological, psychological, and social levels.

Brain Plasticity

The brain's ability to reorganize itself by forming new neural connections throughout life.

Cerebellum

A brain structure that regulates coordination and balance.

Cerebral Cortex

The outer layer of the brain involved in complex functions such as thought and action.

Split Brain Research

Studies involving patients with severed corpus callosum to understand the functions of each hemisphere.

Circadian Rhythm

The natural, internal process that regulates the sleep-wake cycle and other physiological processes.

REM Sleep

A stage of sleep characterized by rapid eye movement and vivid dreams.

Insomnia

A sleep disorder characterized by difficulty falling or staying asleep.

Narcolepsy

A sleep disorder characterized by excessive daytime sleepiness and sudden sleep attacks.

Sensation

The process by which our sensory receptors and nervous system receive and represent stimulus energies.

Psychophysics

The study of the relationship between physical stimuli and the sensations and perceptions they produce.

Signal Detection Theory

A theory that predicts how and when we detect the presence of a faint stimulus amid background noise.

Absolute Threshold

The minimum intensity of a stimulus that can be detected 50% of the time.

Weber's Law

A principle stating that the difference threshold is a constant proportion of the original stimulus.

Transduction

The process of converting one form of energy into another, particularly in sensory systems.

Rods

Photoreceptor cells in the retina that are responsible for vision in low light conditions.

Cones

Photoreceptor cells in the retina that are responsible for color vision and function best in bright light.

Trichromatic Theory

A theory of color vision that proposes three types of cones sensitive to red, green, and blue light.

Opponent-Process Theory

A theory of color vision that suggests color perception is controlled by the activity of two opponent systems: a blue-yellow mechanism and a red-green mechanism.

Feature Detectors

Neurons in the brain that respond to specific features of visual stimuli, such as edges, angles, and movement.

Afterimages

Visual sensations that remain after the original stimulus has been removed.

Ganglion cells

Neurons in the retina that receive visual information from photoreceptors and transmit it to the brain.

Dichromatism

A type of color vision deficiency where individuals can only perceive two colors.

Monochromatism

A condition where an individual can only see in shades of one color.

Prosopagnosia

A neurological condition characterized by the inability to recognize faces.

Blindsight

A condition in which a person can respond to visual stimuli without consciously perceiving them.

Parallel Processing

The ability of the brain to simultaneously process multiple aspects of a stimulus, such as color, motion, and shape.

Wavelengths

The distance between successive peaks of a wave, which determines the color of light.

Hue

The attribute of a color that allows it to be classified as red, blue, green, etc.

Intensity

The amount of energy in a light or sound wave, which influences how bright or loud it is perceived.

Cornea

The transparent front part of the eye that covers the iris and pupil and helps to focus light.

Pupil

The adjustable opening in the center of the eye that regulates the amount of light entering.

Iris

The colored part of the eye that controls the size of the pupil.

Retina

The light-sensitive layer of tissue at the back of the eye that converts light into neural signals.

Blind Spot

The point in the retina where the optic nerve exits the eye, lacking photoreceptors.

Visual Nerve (optic nerve)

The nerve that transmits visual information from the retina to the brain.

Lens

The transparent structure in the eye that focuses light onto the retina.

Accommodation

The process by which the eye adjusts the lens to focus on objects at different distances.

Nearsightedness

A vision condition where close objects appear clear, but distant objects are blurry.

Farsightedness

A vision condition where distant objects are seen clearly, but close objects are blurry.

Fovea

The small central pit in the retina that provides the clearest vision.

Photoreceptors

Cells in the retina that convert light into electrical signals.