module 4

why is the pituitary gland called a master gland

responding to signals from the hypothalamus, the pituitary releases hormones that trigger other endocrine glands to secrete hormones that in turn influence brain and behavior

action potential

a neural impulse; a brief electrical charge that travels down an axon, neuron firing an impulse, brief electrical charge that travels down its axon

dendrites

a neuron's bushy, branching extensions that receive messages and conduct impluses toward the cell body, short

reuptake

a neurotransmitter's reabsorption by the sending neuron, the sending neuron reabsorbs the excess neurotransmitters

adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine/adrenaline and noradrenaline) that help arouse the body in times of stress, ANS orders them, autonomic (part of peripheral) nervous system, increase heart rate, blood pressure, and blood sugar, surge of energy, linger when emergency passes

reflex

a simple, automatic response to a sensory stimulus, such as the knee-jerk response, spinal cord, ascending neural fibers send up sensory information, descending fibers send back motor-control information, reflexes, automatic responses to stimuli

interneurons

communicate within the CNS and intervenes between incoming and outgoing messages

neurons

nerve cells, basic building block of the nervous system, differ, all variations on the same theme, each has a cell body and its branching dendrite fibers that receive information and conduct it toward the cell body, axon fibers that pass the message through its terminal branches to other neurons or to muscles or glands, dendrites listen, axons speak, neurons trasmit messages when stimulated by signals from our seneses or when triggered by chemical signals from neighboring neurons, neuron fires impulse called the action potential, brief electial charge, travels down its axon, neurons generate electricity from chemical events, exchange ions, neuron firing changes axon's security parameters, resting = refractory period, pumps positively charged sodium ions back outside, neuron is a miniature decision making device, complex calculations as it receives signals from other neurons, most are excitatory, accelerator, some inhibitory, brake, if excitatory-inhibitory=the threshold --> action potential, travels down axon, more stimulation above the threshold will not increase the neural impulse's intensity, all-or-none-response, does not effect action potential's strength or speed, a strong stimulus can only trigger more neurons to fire and to fire more often

all or none response

neuron's reaction, react if above threshold, more stimulation doesn't increase the neural impulse's intensity, does not affect the action potential's strength or speed, just causes more neurons to fire and fire more often

protoplasmic kisses

unions of neurons, dendrites and axons don't quite touch, like air kisses so you don't mess up makeup

do the brains of humans and other animals operate similarly

yes, you could not distinguish between small samples of brain tissue from a human and a monkey, allows scientists to study simple animals to discover how our neural systems operate, animals differ from us but their nervous systems operate similarly, human brain more complex, but follows the same principles

acetylcholine

ACh, one of the best-understood neurotransmitters, role in learning and memory, messenger at every junction between motor neurons, (carry information from the brain and spinal cord to the body's tissues) and skeletal muscles, when it is released to our muscle cell receptors, the muscle contracts, anesthesia blocks it, muscle cannot contract and we are paralyzed

spinal cord

CNS, two way information highway connecting between the peripheral nervous system and the brain, ascending neural fibers send up sensory information, descending fibers send back motor-control information,neural pathways governing our reflexes, automatic responses to stimuli, single sensory neuron and single motor neuron, communication through interneuron, pain, travels via sensory neurons to interneurons in your spinal cord, respond by activating motor neurons leading to the muscles, pain-reflex pathway runs through the spinal cord and back out, react before your brain receives and responds to the information that causes you to feel pain, information travels to and from the brain by the spinal cord, if severed you would not feel your body

myelin sheath

a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next, layer of fatty tissue that insulates axons, speeds their impulses

interneurons

between sensory input and motor output, information processed in the brain's internal communication system via its interneurons, complexity mostly in interneurons, billions, neurons within the brain and spinal cord that communicate interally and intervene between the sensory inputs and motor outputs

antagonists

bind to reeptors, effect is instead to block a neurotransmitter's functions, botulin, poison, paralysis, botox, smooth wrinkles by paralyzing facial muscles, enough like natural neurotransmitter to occupy its receptor site and block its effect, not similar enough to stimulate the receptor

how are the nervous and endocrine systems alike, and how do they differ

both of these communication systems produce chemical molecules that act on the body's receptors to influence our behavior and emotions, the endocrine system, secretes hormones into the bloodstream, delivers its messages much more slowly than the speedy nervous system, and the effects of the endocrine system's messages tend to linger much longer than those of the nervous system

neural networks

brain's neurons cluster into work groups, neurons have to talk/communicate with each other, meet at synapses, network with nearby neurons with which they can have short, fast connections

feedback system

brain, pituitary, other glands, hormones, body and brain, intimate connection of the nervous and endocrine systems, nervous system directs endocrine secretions, affect the nervous system, brain in charge

sensory neurons

carry incoming messages from sensory receptors to the CNS

motor neurons

carry information from the brain and spinal cord to the body's tissues

motor neurons

carry instructions from the central nervous system out to the body's muscles, millions, neurons that carry outgoing information about the brain and spinal cord to the muscles and glands

sensory neurons

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

motor neurons

carry outgoing messages from the CNS to muscles and glands

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons, when released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse, chemical messengers released when action potential reaches the knob-like terminals at an axon's end, particular brain pathway may use only one or two neurotransmitters, and particular neurotransmitters may affect specific behaviors and emotions, don't operate in isolation, interact, effect vary with the receptors they stimulate, acetylcholine

biological perspective

concerned with the links between biology and behavior, includes psychologists working in neuroscience, behavior genetics, and evolutionary psychology, may call themselves behavioral neuroscientists, neuropsychologists, behavior geneticists, psysioloical psychologists or biopsychologists

autonomic nervous system

controls our glands and the muscles of our interal organs, influencing such functions as glandular activity, heartbreat, and digestion, automatic pilot, consciously overriden, usually operates on its own autonomously, two important basic functions, sympathetic nervous system arouses and expends energy, alarms or challenges, speeds heartbeat, raises blood pressure, slows digestion, raises blood sugar, cools with perspiration, alert and ready for action, parasympathetic nervous system, stress subsides, opposite effects, conserves energy, decreases heartbeat, lowers blood sugar, work together to keep you stable, 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

when a neuron fires an action potential, the information travels through the axon, the dendrites, and the axon's terminal branches, but not in that order, place these three structures in the correct order

dendrites, axon, axon's terminal branches

nerves

electrial cables formed of bundles of axons link the CNS with the body's receptors, muscles, and glands, bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs

somatic nervous system

enables voluntary control of our skeletal muscles, reports to brain the current state of your skeletal muscles and carries instructions back, trigger hand to turn page, the division of the peripheral nervous system that controls the body's skeletal muscles, also called the skeletal nervous system

resting potential

fluid outside an axon's membrane has positively charged ions, fluid inside has negatively charged ions, surface selective about what it allows through its gates, selectively pereable

curare poisoning paralyzes its victims by blocking ACh receptors involved in muscle movements. morphine mimics endorphin actions. what is an agonist, and which is an antagonist?

morphine is an agonist; curare is an antagonist

endorphines

morphine within, natural, opiate-like neurotransmitters linked to pain control and pleasure, endogenous morphine, runners high, acupuncture, indifference to pain in some severely injured people, don't flood brain with endorphins, heroin and morphine, brain may stop producing its own opiates, brain deprived of opiates when drug withdrawn, intense discomfort, drugs affect brain chemisty at synapses, exciting or inhibing neurons' firing

sir charles sherrington

neurons interweave intricately, trouble seeing where one neuron ends and another begins, noticed neural impulses taking an unexpectedly long time to travel a neural pathway, brief interruption in the transmission, meeting point between neurons = synapse

what happens in the synaptic gap? what is reuptake?

neurons send neurotransmitters (chemical messengers) to one another across this tiny space between one neuron's terminal branch the the next neuron's dendrite. in reuptake, a sending neuron reabsorbs the extra neurotransmitters

serotonin, dopamine, and endorphines are all chemical messengers called

neurotransmitters

candance pert and solomon snyder

neurotransmitters, radioactive tracer to morphine, showing where it was taken up in an animal's brain, morphine, opiate drug that elevates mood and eases pain, bound to areas linked with mood and pain sensations, opiate receptors, brain produces its own opiates, body releases several types of neurotransmitter molecules similar to morphine in response to pain and vigorous exercise, endorphins (endogenous morphine), runners high, acupuncture, indifference to pain in severely injured people

what bodily changes does your autonomic nervous system ANS direct before and after you give an important speech

responding to this challenge, your ANS's sympathetic division will arouse you, it accelerates your heartbeat, raises your blood pressure and blood sugar, slows your digestion, and cools you with perspiration, after you give the speech, your ANS's parasympathetic division will reverse these effects

refractory period

resting pause, neuron pumps the positively charged sodium ions back outside

selectively peremable

selective about what it allows through its gates, positive outside negative inside axon, resting potential

agonist molecules

similar enough to a neurotransmitter to bind its receptor and mimic its effect, some opiate drugs agonist, produce a temporary high, amplifying normal sensations of arousal or pleasure

how does our nervous system allow us to experience the difference between a slap and a tap on the back

stronger stimuli (the slap) cause more neurons to fire more frequently than happens with weaker stimuli (the tap)

phrenology

studying bumps on the skull to reveal a person's mental abilities and character traits, franz gall, failed, faded, succeeded in focusing attention on the localization of function, the idea that various brain regions have particular functions

endocrine system

the body's slow chemical communication system, a set of glands that secrete hormones into the bloodstream, chemical messengers, act on the brain to influence interest in sex, food, and aggression, interconnected with nervous system, both produce molecules that act on receptors, nervous system faster, endocrine messengers go through bloodstream, effects last longer, some chemically identical to neurotransmitters

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems, 3 types of neurons, sensory neurons, motor neurons, and interneurons

central nervous system (CNS)

the brain and the spinal cord, body's decision maker

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations, arouses and expends energy if something alarms or challenges you, accelerate your heartbeat, raise your blood pressure, slow your digestion, raise your blood sugar, cool you with perspiration, making you alert, opposite of parasympathetic nervous system

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy, opposite of sympathetic nervous system, decreases heartbeat, lowers blood sugar, conserving energy

pituitary gland

the endocrine system's most influential gland, under the influence of the hypothalamus, the pituitary regulars growth and controls other endocrine glands, pea size in the core of the brain, adjacent brain area = the hypothalamus, releases certain hormones, grwoth hormone, stimulates physical development, oxytocin, enables contractions associated with birthing, milk flow during nursing, and orgasm, pair bonding, group cohesion, and social trust, influence the release of hormones by other endorcine glands, master gland (own master is hypothalamus), triggers sex glands to release sex hormones, influence brain and behavior, stress, pituitary relase a hormone that causes your adrenal glands to flood your body with cortisol, stress hormone that increases blood sugar

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron, the tiny gap at this junction is called the synaptic gap or synaptic cleft

threshold

the level of stimulation required to trigger a neural impulse, if excitatory signals - inhibitory signals = above threshold --> action potential, higher and higher stimulation over the threshold does not increase the impulse's intensity, all or none response, strong stimulus can trigger more neurons to fire and fire more often however

axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands, long, some encased in a myelin sheath that insulates them in a layer of fatty tissue and speeds their impulses, resting axon: fluid outside an axon's membrane has mostly positively charged ions, inside has negatively charged ions, positive outside negative inside, resting potential, tightly guarded, selectively permeable, when neuron fires, security parameters change, first section of axon opens, positively charged sodium ions flood through the cell membrane, depolarizes that axon section, causing more axon channels to open on after another, resting pause = refractory period, neuron pumps the positively charged sodium ions back outside

peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body, gather information and transmitting central nervous system decision to other body parts, somatic and autonomic

what do phrenology and psychology's biological perspective have in common

they share a focus on the links between biology and behavior. phrenology faded because it had no scientific basis- skull bumps don't reveal mental traits and abilities (was useful though because it hinted that various brain regions have particular functions)