Unit 1a Vocabulary

ap psych

Nature

The idea that our behaviors and thoughts are a result of “inborn” factors like our genetic makeup

Nurture

The idea that our behaviors and thoughts are a result of our sensations of the world around us

Evolutionary psychology

The study of the evolution of behavior and the mind, using principles of natural selection

Behavior genetics

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

Natural selection

The principle that the inherited traits enabling an organism to survive and reproduce in a particular environment will (in competition with other trait variations) most likely be passed on to succeeding generations

Mutation

A random error in gene replication that leads to a change

Environment

Every nongenetic influence, from prenatal nutrition to the people and things around us

Heredity

The genetic transfer of characteristics from parents to offspring

Genes

The biochemical units of heredity that make up the chromosomes

Genome

The complete instructions for making an organism, consisting of all of the genetic material in that organism’s chromosomes

Eugenics

The pseudo-scientific view that the genetic makeup of a population can be “improved” by techniques like selective breeding and selective sterilization

Identical (monozygotic) twins

Twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

Fraternal (dizygotic) twins

Twins who develop from separate fertilized eggs; they are genetically no closer than brothers and sisters, but they share a fetal environment

Epigenetics

The study of the molecular mechanisms by which environments can influence genetic expression (without a DNA change)

Nervous system

The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

Central nervous system (CNS)

The brain and spinal cord

Peripheral nervous system (PNS)

The sensory and motor neurons that connect the central nervous system to the rest of the body

Nerves

Bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sensory organs

Reflex

A simple, automatic response to a sensory stimulus, such as the knee-jerk reaction

Autonomic nervous system

The part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart)

Somatic nervous system

The division of the peripheral nervous system that controls the body’s skeletal muscles

Sympathetic nervous system

The division of the autonomic nervous system that arouses the body, mobilizing its energy

Parasympathetic nervous system

The division of the autonomic nervous system that calms the body, controlling its energy

Sensory (afferent) neurons

Nerves that carry information from the sensory inputs to the central nervous system

Motor neurons

Nerves that carry information from our brain to our muscles and endocrine system

Interneurons

Neurons within the brain and spinal cord that communicate between sensory inputs and motor outputs

Neuron

A nerve cell; the building block cell of the nervous system

Cell body

The part of a neuron that contains the nucleus; the cell’s life-support center

Dendrites

A neuron’s often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body

Axon

The segmented neuron extension that passes messages through its branches to other neurons or to muscles or glands

Myelin sheath

A fatty tissue layer segmentally encasing the axons of some neurons; it enables vastly greater transmission speed as neural impulses hop from on node to the next

Synapse

The area where neurons connect and communicate with one another

Glial cells

Cells in the nervous system that support, nourish, and protect neurons; they may also play a role in learning, thinking, and memory

Reflex arc

A neural pathway that doesn’t involve the brain, using sensory, motor, and interneurons

Action potential

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

All-or-nothing principle

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

Depolarization

The process of a neuron becoming activated, as negatively and positively-charged ions are exchanging places across an axon’s membrane

Reuptake

A neurotransmitter’s reabsorption by the sending neuron

Neurotransmitters

The chemical messengers of the nervous system

Refractory period

A brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state

Resting potential

An axon’s non-activated state, when it's filled with mostly negatively-charged ions and surrounded by mostly positively-charged ions

Threshold

The level of stimulation required to trigger a neural impulse

Multiple Sclerosis

A disease of the central nervous system with many physical and cognitive symptoms; caused by a degrading of the myelin sheaths that enable efficient neurotransmission

Myasthenia Gravis

An auto-immuine disorder in which ACh transmission is inhibited, leading to increased muscular weakness and possible paralysis

Excitatory neurotransmitters

Neurotransmitters that increase the likelihood of a neuron reaching action potential

Inhibitory neurotransmitters

Neurotransmitters that decrease the likelihood of a neuron reaching action potential

Antagonist

A molecule that inhibits or blocks a neurotransmitter’s action

Agonist

A molecule that increases a neurotransmitter’s action

Dopamine

Neurotransmitter associated with muscle movement, attention, learning; excess is linked to schizophrenia; shortage is linked to Parkinson’s disease

Norepinephrine

Neurotransmitter that helps control alertness and arousal

GABA

A major inhibitory neurotransmitter; undersupply linked to seizures

Serotonin

Neurotransmitter that affects mood, hunger, sleep, arousal; undersupply is linked to depression

Glutamate

A major excitatory neurotransmitter; oversupply can overstimulate the brain and produce migraines or seizures

Endorphins

Neurotransmitters that influence the perception of pain and pleasure

Substance P

Neurotransmitter involved in pain perception and immune response

Acetylcholine (ACh)

Neurotransmitter that enables muscle action, learning, memory; undersupply is linked to Alzheimer’s disease

Endocrine system

The body’s “slow” chemical communication system; a set of glands and fat tissue that secrete hormones into the bloodstream

Hormones

Messengers of the endocrine system; move through the bloodstream

Leptin

Hormone that decreases feelings of hunger

Melatonin

Hormone that helps regulate sleep cycles

Adrenaline

Hormone associated with the “fight-or-flight” response, activities the sympathetic nervous system

Ghrelin

Hormone that increases feelings of hunger

Oxytocin

Hormone that stimulates orgasms, contractions during labor, and maternal milk production

Psychoactive drugs

A chemical substance that alters the brain, causing changes in perceptions and moods

Reuptake inhibitor

A drug that blocks reabsorption of certain neurotransmitters in the brain, increasing their levels and neurotransmission; used to treat depression, among other conditions

Stimulants

Drugs (such as caffeine, nicotine, and the more powerful amphetamines, cocaine, and Ecstasy) that excite neural activity and speed up body functions

Caffeine

A mild stimulant that reduces drowsiness; can cause tremors and anxiety at high doses

Cocaine

A potent stimulant associated with feelings of euphoria

Opioids

Opium and its derivatives, such as morphine and heroin; they depress neural activity, temporarily reducing pain and anxiety

Heroin

A highly-addictive opioid; reduces feelings of pain and produces feelings of euphoria; reduces your body’s natural endorphin production

Addiction

Compulsive substance use (and sometimes dysfunctional behavioral patterns) that continued despite harmful consequences

Depressants

Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions

Alcohol

A commonly-used depressant that slows brain activity that controls judgment and inhibitions; at lower-levels, users experience mild excitement and declines in motor and cognitive performance; at higher levels, users may lose consciousness and respiratory-areas of the brain may shut down 

Hallucinogens

Psychedelic (“mind-manifesting”) drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input

Marijuana

A mild hallucinogen associated with a sense of well-being, relaxation, increased appetite, and cognitive impairment

LSD

A powerful hallucinogenic drug; also known as “acid” (lysergic acid diethylamide); produces distortions in, especially, visual perception

Tolerance

The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug’s effect

Withdrawal

The discomfort and distress that follow discontinuing an addictive drug or behavior