AP Psych - Unit 1

Consciousness

Our awareness of ourselves and our environment, including our thoughts, feelings, sensations, and surroundings.

Dendrites

Branching parts of a neuron that receive incoming signals from other neurons.

Soma

The cell body of a neuron. It contains the nucleus, keeps the neuron functioning, and integrates incoming signals.

Axon

A long extension of a neuron that carries the electrical impulse, or action potential, away from the soma.

Myelin Sheath

A fatty covering around an axon that insulates it and speeds up neural transmission.

Axon Terminals

The ends of an axon that release neurotransmitters into the synapse.

Receptors

Protein sites on receiving neurons where specific neurotransmitters bind.

Order of Neuron Parts

Dendrites → Soma → Axon → Axon Terminals. Dendrites receive, the soma processes, and the axon sends.

Endorphins

Neurotransmitters involved in pain relief and pleasure. They act as the body's natural painkillers.

Reuptake

The process in which neurotransmitters in the synapse are reabsorbed by the neuron that released them.

Genes

Units of heredity made of DNA that provide instructions contributing to physical and behavioral traits.

DNA

The molecule containing genetic information and instructions used in development and functioning.

Chromosomes

Threadlike structures made of DNA that contain genes. Humans normally have 46 chromosomes, or 23 pairs.

Genes vs. Chromosomes

Genes are segments of DNA containing genetic information, while chromosomes are structures made of DNA that contain many genes.

Plasticity

The brain's ability to change and reorganize itself in response to learning, experience, or injury.

Plasticity After Brain Damage

The brain can sometimes reorganize functions or form new connections following damage, especially in younger brains.

Neurogenesis

The formation of new neurons. It occurs in limited areas of the adult brain.

Evolutionary Psychology

The study of how natural selection and evolution may have shaped behavior and psychological traits that helped our ancestors survive and reproduce.

Cognitive Neuroscience

The study of how brain activity is connected to cognition, including thinking, memory, language, and perception.

Behavior Genetics

The study of how genes and environment contribute to differences in behavior and psychological traits.

Nature

Genetic and biological influences on behavior and psychological characteristics.

Nurture

Environmental influences and experiences that affect behavior and psychological characteristics.

Nature vs. Nurture

The study of how genetic and environmental influences contribute to behavior. Modern psychology emphasizes that nature and nurture interact rather than operating independently.

Gene-Environment Interaction

The idea that genetic predispositions and environmental influences interact to shape traits and behavior.

Genotype

An individual's genetic makeup.

Phenotype

An individual's observable characteristics, produced through interactions between genetic makeup and environmental influences.

Genotype vs. Phenotype

Genotype = genetic makeup; phenotype = observable traits resulting from genes interacting with the environment.

Identical Twins

Twins that develop when one fertilized egg splits into two. They share essentially 100

Fraternal Twins

Twins that develop from two different fertilized eggs. Like ordinary siblings, they share about 50

Why Are Twins Important in Psychology?

Twin studies help psychologists investigate nature versus nurture by comparing people with different degrees of genetic similarity and, in some studies, different environments.

Shared Environment

Environmental experiences that people raised together, such as siblings, have in common.

Nonshared Environment

Experiences that differ between individuals, even when they grow up in the same household.

Effect of Home Life in Behavior Genetics

Home environments can influence behavior through parenting, culture, learning opportunities, nutrition, and experiences. Behavior is generally shaped by interactions between genes and environment.

Heritability

The proportion of variation among individuals in a particular population that can be statistically associated with genetic differences.

What Does High Heritability Mean?

High heritability means genetic differences explain a relatively large amount of variation in a trait within a particular population and environment. It does NOT mean an individual's trait is a certain percentage genetic.

Heritability and Individuals

Heritability does NOT tell you what percentage of one person's trait is genetic. It describes genetic contributions to variation among people in a particular population and environment.

Can Heritability Change?

Yes. Heritability can differ between populations and environments because both genes and environmental conditions influence variation in traits.

Can a Highly Heritable Trait Be Influenced by Environment?

Yes. High heritability does not mean the environment is unimportant or that a trait cannot change.

Sensory Neurons

Neurons that carry information from sensory receptors toward the brain and spinal cord. They are also called afferent neurons.

Interneurons

Neurons primarily in the brain and spinal cord that process information and connect sensory neurons with motor neurons.

Motor Neurons

Neurons that carry commands from the brain and spinal cord to muscles and glands. They are also called efferent neurons.

Order of Neuron Types

Sensory → Interneuron → Motor. Sensory neurons bring information IN, interneurons PROCESS it, and motor neurons send commands OUT.

Afferent Neurons

Sensory neurons that carry information FROM sensory receptors TO the central nervous system.

Efferent Neurons

Motor neurons that carry commands FROM the central nervous system TO muscles and glands.

SAME Mnemonic

Sensory = Afferent, Motor = Efferent.

Multiple Sclerosis (MS)

A disease that damages the myelin sheath around neurons, causing neural communication to become slower or disrupted and potentially affecting movement, sensation, and coordination.

Neural Transmission

Dendrites receive signals → soma integrates them → an action potential travels down the axon → axon terminals release neurotransmitters → neurotransmitters cross the synapse and bind to receptors.

Synapse

The tiny gap between the axon terminal of one neuron and the receiving neuron across which neurotransmitters travel.

Neurotransmitters

Chemical messengers released by neurons that cross the synapse and bind to receptor sites on other cells.

Action Potential

The electrical impulse that travels down a neuron's axon after the neuron reaches its threshold.

Threshold

The minimum level of stimulation required for a neuron to fire an action potential.

All-or-None Principle

A neuron either fires a complete action potential or does not fire at all. A stronger stimulus does not create a stronger action potential; it can cause neurons to fire more frequently.

Resting Potential

The neuron's stable negative electrical charge when it is not firing.

Depolarization

The change in a neuron's electrical charge that occurs when positively charged ions enter the neuron during an action potential.

Refractory Period

A brief period after a neuron fires during which it must reset before it can fire normally again.

Agonist

A substance that increases neurotransmitter activity by mimicking a neurotransmitter or otherwise increasing its effects. Think agonist = GO.

Antagonist

A substance that decreases neurotransmitter activity, often by blocking receptor sites. Think antagonist = AGAINST.

Excitatory Neurotransmitter

A neurotransmitter that makes the receiving neuron more likely to fire. Glutamate is the brain's major excitatory neurotransmitter.

Inhibitory Neurotransmitter

A neurotransmitter that makes the receiving neuron less likely to fire. GABA is the brain's major inhibitory neurotransmitter.

Reflex

A simple, automatic response to a sensory stimulus, such as quickly pulling your hand away from something hot.

Reflex Arc

A neural pathway that allows a rapid automatic response to a stimulus, often involving processing through the spinal cord before the brain fully processes the event.

Serotonin

A neurotransmitter involved in mood, sleep, appetite, and arousal. Abnormal serotonin activity is associated with some mood disorders.

Substance P

A neurotransmitter involved in transmitting pain signals and contributing to the perception of pain.

Norepinephrine

A neurotransmitter involved in alertness, arousal, attention, and the body's stress response.

Acetylcholine

A neurotransmitter involved in muscle movement, learning, and memory. It enables communication between motor neurons and skeletal muscles.

GABA

The brain's major inhibitory neurotransmitter. It reduces or slows neural activity and is involved in functions such as sleep and relaxation.

Glutamate

The brain's major excitatory neurotransmitter. It increases neural activity and plays an important role in learning and memory.

Dopamine

A neurotransmitter involved in movement, motivation, reward, learning, and attention.

SSNAGGED

Mnemonic for 8 major neurotransmitters: Serotonin, Substance P, Norepinephrine, Acetylcholine, GABA, Glutamate, Endorphins, and Dopamine.

GABA vs. Glutamate

GABA is the brain's major INHIBITORY neurotransmitter and decreases neural activity, while glutamate is the major EXCITATORY neurotransmitter and increases neural activity.

Central Nervous System (CNS)

The brain and spinal cord.

Peripheral Nervous System (PNS)

All nerves outside the brain and spinal cord that connect the CNS to the rest of the body.

Somatic Nervous System

The division of the peripheral nervous system that controls voluntary skeletal muscle movement and carries sensory information.

Autonomic Nervous System

The division of the peripheral nervous system that controls involuntary functions of internal organs and glands.

Sympathetic Nervous System

The division of the autonomic nervous system that arouses the body and prepares it for action during fight-or-flight.

Parasympathetic Nervous System

The division of the autonomic nervous system that calms the body and conserves energy during rest-and-digest.

Divisions of the Nervous System

Nervous System → CNS + PNS. PNS → Somatic + Autonomic. Autonomic → Sympathetic + Parasympathetic.

Fight-or-Flight Response

A response to a perceived threat in which the sympathetic nervous system increases arousal, including heart rate and breathing, while preparing the body for action.

Spinal Cord

Part of the central nervous system that carries information between the brain and body and controls simple reflexes.

Brainstem

The lower portion of the brain connecting to the spinal cord. It controls basic survival functions such as breathing, heart rate, sleep, and arousal.

Medulla

Part of the brainstem that controls vital automatic functions such as breathing, heart rate, and blood pressure.

Pons

Part of the brainstem involved in sleep, arousal, and coordinating movement. It also helps relay information between different parts of the brain.

Reticular Formation

A network of neurons running through the brainstem that helps control arousal, alertness, and attention.

Thalamus

The brain's major sensory relay station. It sends most incoming sensory information, except smell, to the appropriate areas of the cerebral cortex.

Hypothalamus

A brain structure involved in maintaining homeostasis and regulating hunger, thirst, body temperature, and motivated behaviors. It also helps control the pituitary gland.

Homeostasis

The body's tendency to maintain a stable and balanced internal state.

Amygdala

Part of the limbic system involved in processing emotions, especially fear, aggression, and responses to threats.

Hippocampus

Part of the limbic system important for forming new explicit memories and processing memories for long-term storage.

Limbic System

A group of interconnected brain structures involved in emotion, motivation, memory, and basic drives.

Cerebellum

Located at the back of the brain; coordinates balance, posture, voluntary movement, and motor learning.

Pituitary Gland

The endocrine gland sometimes called the master gland. Controlled by the hypothalamus, it releases hormones that regulate growth and influence other endocrine glands.

Adrenal Glands

Endocrine glands located above the kidneys that release hormones such as epinephrine and norepinephrine during stress.

Epinephrine

Also called adrenaline; a hormone released by the adrenal glands that increases physiological arousal during the fight-or-flight response.

Endocrine System

The body's slower chemical communication system. Its glands release hormones into the bloodstream that influence growth, metabolism, reproduction, stress, mood, and other processes.

Hormones

Chemical messengers produced by endocrine glands and carried through the bloodstream to affect other tissues and organs.

Nervous System vs. Endocrine System

The nervous system communicates rapidly using neural signals, while the endocrine system communicates more slowly using hormones carried through the bloodstream and often produces longer-lasting effects.

Cerebrum

The largest part of the brain, consisting of the two cerebral hemispheres and responsible for many higher mental processes.

Cerebral Hemispheres

The left and right halves of the cerebrum, connected by the corpus callosum.

Corpus Callosum

A thick band of nerve fibers connecting the left and right cerebral hemispheres, allowing the two sides to communicate.

Cerebral Cortex

The thin outer layer of the cerebral hemispheres involved in perception, thinking, language, memory, and voluntary movement.