Neurotransmitters, Endocrine & Nervous Systems, Psychoactive Drugs

Nervous System

the body's speedy, electrochemical communication network, consisting of all the peripheral and central nervous systems; made up of neurons (nerve cells) that communicate via chemical messengers called neurotransmitters

Central Nervous System (CNS)

the brain and the spinal cord;

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body; responsible for gathering information and for transmitting CNS decisions to other body parts

Nerves

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sensory organs; pass messages to other neurons or to muscles and glands; link the CNS with the body's sensory receptors, muscles, and glands

Sensory (afferent) neurons

neurons that carry incoming information/messages from the body's tissues and and sensory receptors to the brain and spinal cord for processing - inward (millions)

Motor (efferent) neurons

neurons that carry outgoing information/instructions from the brain and spinal cord (CNS) to the muscles and glands - outward (millions)

Interneurons

neurons within the brain and spinal cord (CNS), they communicate internally and process information between the sensory inputs and motor outputs; process information between the sensory input and motor output; where our complexity resides (billions)

Somatic Nervous System

enables voluntary control our skeletal muscles; the division of the peripheral nervous system that controls the body's skeletal muscles - also called the skeletal nervous system

Autonomic Nervous System (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart); influences functions such as glandular activity, heartbeat, and digestion (autonomic = self regulation)

Sympathetic Nervous System

division of the ANS; arouses and expends energy (fight or flight) - makes you alert and ready for action; arouses the body, mobilizing its energy

Parasympathetic Nervous System

division of the ANS; calms the body, conserving its energy, put into effect after the stress from Sympathetic Nervous System subsides

Goal of sympathetic and parasympathetic nervous systems

work together to keep our bodies in a steady internal state called homeostasis

Reflex

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

Neural Networks

work groups that individual neurons cluster into - develop fast, short connections that strengthen with learning

Brain

Enables our humanity - thinking, feeling, acting

Spinal Cord purpose

two-way information highway connecting the peripheral nervous system and the brain - information travels to and from the brain by the way of the spinal cord

Spinal Cord composition

Ascending neural fibers send up sensory information, descending neural fibers send back motor control information

Psychoactive Drug

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

depressants

drugs that reduce neural activity and slow body functions

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

Barbiturates/tranquilizers

drugs that depress CNS activity, reducing anxiety but impairing memory and judgement

Opiods

opium and its derivatives; they depress neural activity, temporarily lessening pain and anxiety

Depressants ex.

Alcohol, Barbiturates, opioids (heroin, morphine, opium, methadone)

Stimulants

drugs that excite neural activity and speed up body functions

Stimulants ex.

Nicotine, Cocaine, Meth, Ecstasy

Hallucinogens

psychedelic "mind manifesting" drugs that distort perceptions and evoke sensory images in the absence of sensory input

Hallucinogens ex.

LSD, Marijuana

Near death experience

an altered state of consciousness reported after a close brush with death , such as a cardiac arrest, and is often similar to drug induced hallucinations

Agonists

chemicals/drugs that bind to the receptors and mimic the effects of neurotransmitters - disinhibit

Antagonists

chemicals/drugs that bind to receptors and block the functioning of neurotransmitters

Selective Serotonin Reuptake Inhibitors (SSRIs)

medication that treats depression and anxiety by preventing the reuptake of serotonin, thereby increasing the brain's supply of serotonin

Endocrine System

body's "slow" chemical communication system; a set of glands that secretes hormones into the bloodstream

Endocrine System glands

Pituitary & Adrenal

Glands

Organs or tissues in the body that create and secrete hormones

Hormones

chemical messengers that are produced by the endocrine glands and are carried by the bloodstream to all parts of the body

Pituitary gland

controls growth and regulates other glands; influences release of hormones by other endocrine glands; ex. triggers sex glands to secrete sex hormones; releases oxytocin

Oxytocin

hormone that promotes bonding, group cohesion, and social trust

Adrenal Glands

pair of endocrine glands that sit just above the kidney, secrete hormones that help arouse the body in times of stress or emergency - fight or flight

What does Adrenal glands release

Epinephrine & norepinephrine; adrenaline v noradrenaline; these hormones increase heart rate, blood pressure, and blood sugar but slow down digestion

Physical Dependence

the user experiences physical pain and intense cravings from a drug when drug use stops

Psychological dependence

user experiences psychological need for a drug - all drugs have the potential to be this

Alcohol

suppresses REM, lessens memory, affects judgement, slows reaction-time, shrinks brain, slows down sympathetic nervous system, reduces self awareness; in small amounts acts as stimulant, in excess kills by inhibiting part of brain that controls breathing & heartbeat; inhibits Acetylcholine, increases dopamine

LSD effects

odorless, tasteless, soluble drugs that cause major hallucinations which can last up to 10 hours; causes pupil dilation, increased heart rate, nausea, distortion of special relations, mood alterations, detachment, panic, paranoia, synesthesia, flashbacks, long lasting psychosis, and post LSD depression; NOT physically addictive

LSD chemical effects

block serotonin, increases dopamine in brain

Marijuana

mild hallucinagen

Marijuana chemical effect

Increases dopamine

Ecstasy effects

only a mild hallucinogen; mainly stimulant - "club/love" drug, created for weight loss causes euphoric good feeling, disinhibition, and connectedness to others

Ecstasy chemical effects

increases dopamine and serotonin in the brain, disinhibitor