AP Psych unit 2: Neurons/Nervous system

evolutionary psychology

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

Neurons

a nerve cell; the basic building block of the nervous system.

Gilal Cells

non-neuronal nervous-system cells that support neurons by providing structure, insulation, communication, and nutrient and waste transport.

Reflex Arc

a neural circuit that is involved in a reflex

Interneurons

neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs.

All or nothing principle

a neuron either fires a full action potential once stimulation reaches threshold or does not fire at all; stronger stimulation does not make the action potential stronger.

Depolorization

a reduction in the electric potential across the plasma membrane of a cell

Reuptake

a neurotransmitter’s reabsorption by the sending neuron.

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, conserving its energy.

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

resting potential is the stable, polarized state of a neuron when it is not firing

Threshold

the level of stimulation required to trigger a neural impulse.

Antagonist

a molecule that inhibits or blocks a neurotransmitter’s action

Agonist

a molecule that increases a neurotransmitter’s action.

Reuptake Inhibitor

a substance that interferes with the reabsorption of neurotransmitters

Depressants

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

Stimulants

psychoactive drugs, such as caffeine and cocaine, that typically increase neural activity, boosting alertness, energy, and arousal.

Hallucinogens

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

Opiates

opium and its derivatives, such as morphine and heroin; depress neural activity, temporarily lessening pain and anxiety.

Natural Selection

the principle that inherited traits that better enable 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.

Nervous system

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

CNS (Central Nervous System)

the brain and spinal cord.

ANS (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). Its sympathetic division arouses; its parasympathetic division calms.

Adrenaline

stress hormone and neurotransmitter produced by the adrenal glands. It triggers the body's "fight or flight" response, increasing heart rate, blood pressure, breathing, and blood flow to muscles.

Peripheral Nervous system

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Somatic nervous system

the division of the peripheral nervous system that controls the body’s skeletal muscles. Also called the skeletal nervous system.

sensory neurons

nerve cells that carry messages from the body's tissues and sensory organs inward to the brain and spinal cord, or from sensory receptors to the central nervous system.

motor neurons

carry signals from the brain and spinal cord to muscles, producing movement and muscle contraction.

dopamine

neurotransmitter involved in reward, motivation, voluntary movement, memory, and cognitive function. It is also linked to Parkinson's disease.

norepinephrine

neurotransmitter and hormone that increases alertness and arousal and helps trigger the fight-or-flight response.

GABA (gamma-aminobutyric acid)

a major inhibitory neurotransmitter in the mammalian nervous system and found widely distributed in both invertebrate and vertebrate nervous systems. It is synthesized from the amino acid glutamic acid.

hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.

leptin

signals the hypothalamus about the body's fat stores, promoting satiety and helping maintain stable body weight.

Excitatory neurotransmitters

send signals that stimulate the brain and make the receiving neuron more likely to fire an electrical impulse, or action potential.

inhibitory neurotransmitters

chemical signals that reduce a neuron's chance of firing an action potential.

serotonin

neurotransmitter that helps regulate mood, anxiety, and emotional stability.

gultamate

brain’s main excitatory neurotransmitter, helping neurons communicate and supporting learning and memory.

endorphins

natural, opiate-like neurotransmitters linked to pain control and to pleasure.

acetylcholine

neurotransmitter that triggers muscle contraction and supports learning and memory.

substance P

neuropeptide neurotransmitter that helps transmit pain signals through the nervous system.

ghrelin

hormone released by the stomach that travels through the bloodstream and signals the brain to increase hunger.

oxytocin

hormone produced by the hypothalamus and released by the posterior pituitary gland. Known as the "love hormone," it is associated with social bonding, sexual reproduction, parental behaviors, and feelings of love and satisfaction.

psychoactive drugs

a chemical substance that alters perceptions and moods

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

addiction

compulsive substance use or behavior that continues despite harmful consequences, often involving craving, loss of control, and risk of relapse.

withdrawal

the discomfort and distress that follow discontinuing an addictive drug or behavior.

melatonin

helps in the initiation of sleep and in the regulation of the sleep-wake cycle