AP Psychology Unit 1 (Part 1)

Interneurons

Neurons in the brain and spinal cord; they communicate internally and process information between sensory inputs and motor outputs

Sensory (Afferent) Neurons

Neurons that carry information from the body’s tissues and sensory receptors to the central nervous system

Motor (Efferent) Neurons

Neurons that carry information from the central nervous system to muscles and glands

Action Potential

A neural impulse; a brief electrical charge that travels down an axon

Dendrites

Neuron’s branching extensions that receive and integrate information from neurotransmitters

Axon

Extension of neuron that passes neural impulses to other neurons, muscles, or glands

Myelin Sheath

Fatty tissue layer encasing some axons; facilitates and speeds up the transmission of neural impulses

Neuron Cell Body

Contains the neuron’s nucleus; keeps the cell alive

Axon Terminal

Ends of axons that release neurotransmitters

Neurotransmitters

Chemical messengers that cross the synaptic gap and bind to receptors on the receiving neuron’s dendrites

Adrenaline (Epinephrine)

Neurotransmitter released in stressful situations; increases heart rate and blood flow, leading to physical boost and heightened awareness; fight or flight

Noradrenaline (Norepinephrine)

Neurotransmitter associated with concentration; affects attention and responding actions in the brain; contracts blood vessels, increases blood flow; concentration

Dopamine

Neurotransmitter associated with pleasure; addiction, movement, and motivation; reinforces behavior

Serotonin

Neurotransmitter associated with mood; contributes to well-being and happiness; helps sleep cycle and digestive system regulation; affected by exercise and light exposure

Endorphins

Natural, opioid-like neurotransmitters linked to pain control and pleasure; creates euphoric feelings

Acetylcholine

Neurotransmitter involved in thought, learning, and memory; activations muscle action in the body

GABA

Calming neurotransmitter; inhibits neurons firing in the CNS; improves focus and contributes to motor control and vision

Glutamate

Most common neurotransmitter; involved in learning and memory; regulates development and creation of nerve contacts

Refractory Period

A period of inactivity after a neuron fires; subsequent action potentials cannot occur until the axon returns to its resting state

All-or-None Response

A neuron’s reaction of either firing (with a full-strength response) or not firing

Threshold Potential

Level of stimulation required to trigger an impulse; when excitatory signals outweigh inhibitory signals by the threshold, an action potential is triggered

Synapse (Synaptic Gap)

The junction between the axon tip of the sending neuron and the dendrites of the receiving neuron

Reuptake

Reabsorption of the neurotransmitters by the sending neuron

Agonist

Molecule that increase a neurotransmitter’s action; increase production or release of a neurotransmitter, block reuptake, or mimic a neurotransmitter

Antagonist

Molecule that inhibits or blocks a neurotransmitter’s action; block production, block release, or occupy receptor sites to block its effect

Nervous System

The body’s electrochemical communications network, consisting of all the nerve cells of the peripheral and central nervous system

Central Nervous System

The brain and spinal cord; makes decisions and sends orders for the body’s tissues; also controls our reflexes

Peripheral Nervous System

The sensory and motor neurons that connect the CNS to the rest of the body; gathers information and transmits CNS decisions to other body tissues

Somatic Nervous System

Division of the PNS that controls the body’s skeletal muscles (AKA skeletal nervous system)

Autonomic Nervous System

Division of the PNS that that controls the glands and the muscles of the internal organs (such as the heart)

Sympathetic Nervous System

Division of the autonomic nervous system that arouses the body and mobilizes the body’s energy; controls the body’s fight-or-flight response

Parasympathetic Nervous System

Division of the autonomic nervous system that calms the body and conserves its energy; rest and digest

Endocrine System

The body’s “slow” (relative to nervous system) chemical communications system; a set of glands and fat tissue that secrete hormones into the bloodstream

Hormones

Chemical messengers manufactured by the endocrine glands; travels through bloodstream and affects other tissues (e.g. epinephrine and oxytocin)

Ovaries

Pair of endocrine glands in females that secrete female hormones (e.g. estrogen and progesterone)

Testes

Pair of endocrine glands in males that secrete male hormones (e.g. testosterone)

Adrenal Glands

Releases epinephrine and norepinephrine in moments of perceived danger; these hormones increase heart rate, blood pressure, and blood sugar, providing a surge of energy to power our fight-or-flight response

Pituitary Gland

The master gland of the endocrine system; controlled by the hypothalamus (adjacent); its secretions direct other endocrine glands to release their hormones; releases growth hormones, oxytocin, etc.

Thyroid

Endocrine gland in the neck; controls speed of metabolism

Pancreas

Endocrine gland that releases the hormone insulin; regulates blood sugar levels

Parathyroid

Endocrine gland that produces the parathyroid hormone; regulates level of calcium in the bloodstream

Brainstem

The central core of the brain; responsible for automatic survival functions; consists of the midbrain, pons, medulla, and reticular formation; the body’s crossover point (control of opposite sides of the body)

Reticular Fomation

Nerve network that travels through the brainstem into the thalamus; filters information and controls arousal; part of the brainstem

Pons

The brainstem part that links the medulla and thalamus; controls automatic facial movements and REM sleep

Autonomic facial movements: blinking, tear/saliva production, chewing, swallowing, breathing rhythm, etc.

Medulla

The brainstem’s base; controls heartbeat and breathing

Cerebellum

Behind the brainstem (not part of brainstem); coordinates movement and balance; enables nonverbal learning (procedural learning, muscle memory);

Limbic System

The neural system located mostly in the forebrain, below the cerebrum; includes the amygdala, hypothalamus, hippocampus, and thalamus; controls basic emotions and drives

Thalamus

Pair of egg-shaped structures atop the brainstem (not part of brainstem); routes sensory information for all senses (except smell); transmits replies to the cerebellum and medulla; part of the limbic system

Hypothalamus

Limbic system neural structure just below the thalamus; directs maintenance functions such as influencing hunger, regulating thirst, and body temp; directs the endocrine system through the pituitary gland

Amygdala

Two lima-bean-sized neural clusters in the limbic system; enables fear and aggression; initiates the fight-or-flight response

Hippocampus

Curved brain structure in the limbic system; processes conscious memories for storage

Nucleus Accumbens

A limbic reward center; dopamine release in the nucleus accumbens reinforces behavior and creates pleasure

Cerebral Cortex

The intricate fabric of interconnected neural cells covering the forebrain’s cerebral hemispheres; the body’s ultimate control and information-processing center

Motor Cortex

A cerebral cortex area at the rear of the frontal lobes that controls voluntary movements

Somatosensory Cortex

A cerebral cortex area at the front of the parietal lobes that registers and processes body touch and movement sensations

Visual Cortex

A cerebral cortex area at the back of the occipital lobes; processes visual information

Auditory Cortex

A cerebral cortex area at top of the temporal lobes; processes auditory information

Association Areas

Areas of the cerebral cortex that are not involved in primary motor or sensory functions; involved in higher mental functions such as learning, remembering, thinking, and speaking

Frontal Lobe

Brain area just behind the forehead; enables linguistic processing, muscle movements, higher-order thinking, and executive functioning (such as making plans and judgments); decision-making, speaking, impulse control

Parietal Lobe

Brain area towards the top-rear; receives sensory input for touch and body position

Occipital Lobe

Brain area at the back of the head; receives information from visual fields

Temporal Lobe

Brain area lying just above the ears; receives auditory information from the opposite ear; enables language processing

Neuroplasticity

The brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Corpus Callosum

Large band of neural fibers connecting the two brain hemispheres; carries messages between them

Brain Lateralization

Tendency for certain cognitive processes and functions to be more dominant in one cerebral hemisphere

Split-Brain Research

Research of patients with split brains (after corpus callosotomy); reveals brain lateralization

Fraternal v. Identical Twins

Identical twins - form from a single fertilized egg (genetically identical)

Fraternal twins - form from separate fertilized eggs (no more genetically similar than ordinary siblings)

Heritability

The percentage of variation of a particular trait among members of a group that is caused by genetics

Broca’s Area

Region in the left frontal lobe; controls language production and expression by controlling muscle movements involved in speech

Wernicke’s Area

Region in the left temporal lobe; involved in language comprehension