exam 1: the body's communication networks Flashcards
central nervous system (CNS)
the brain and spinal cord
peripheral nervous system and its parts (2)
peripheral nervous system: all nerves that radiate from the central nervous system to the rest of the body
somatic nervous system: voluntary control of skeletal muscles; transmits signals from the sensory organs to the CNS; relays motor commands from the CNS to the muscles
autonomic nervous system: connects the CNS to involuntary muscles and organs and also to the body’s glands
parts of the autonomic nervous system in the peripheral nervous system (2)
sympathetic nervous system: arousal system; prepares the body for action (fight or flight)
parasympathetic nervous system: calming system; returns the body to its pre-energized state
pituitary gland in the endocrine system
responsible for releasing a hormone that stimulates the production of all other hormones
nerve cells and their types (sensory, motor, inter)
nerve cells: send and receive information throughout the body in the form of electrochemical signals
sensory neurons: take information from the senses, skin, muscles, and internal organs and send that information to the CNS for processing
motor neurons: transmit signals from the CNS to the muscles, glands, and organs of the body
interneurons: serve as neural connectors between the sensory and motor neurons
glial cells
provide structural support, insulation, and nutrients to the neurons; glue together the nervous system in many ways; help to develop, repair, and speed up the functioning of neurons
the structure of the neuron (soma, den, axon, axon term, myel)
soma (cell body): stores the nucleus of the cell and maintains the chemical balance within the cell
dendrites: receive information from sensory organs and from other neurons and transmit that information they receive to the soma
axons: send impulses from the neuron to muscles, glands, and other neurons
axon terminals: exist at the end of each axon; contain the neurotransmitters
myelin sheath: helps to speed up the functioning of the neuron by preventing chemical leakage
neurotransmitters
chemical messengers that, when they are released, move to the dendrites of other neurons to communicate with the next nerve cell when released
action potential and its phenomenon
action potential: gets triggered if a threshold is reached; when it is triggered, a burst of electrical activity surges through the axon; this stimulation may not trigger the firing of the electrical impulse
all-or-nothing phenomenon: only if the threshold is exceeded does the electrical impulse transmit
mini-brains (3)
brainstem (“core brain”): the old, inner core of the brain that rests on top of the spinal cord; helps to regulate primitive life-support functions; responsible for regulating breathing, heartbeat, and muscle movements
limbic system (“primitive mammalian brain”): responsible for non-human, mammalian functions; increased capacity for motivation and emotion; increased ability for learning and memory
cerebral cortex (“human brain”): allows for higher mental processes; complex forms of learning, memory, and thought; complex uses of language
key structures in the brainstem (med, pons, ret form)
medulla: controls vital, involuntary functions (have no control over but keeps us alive); swallowing, breathing, heart rate
pons: helps to coordinate movement and plays a role in sleep and arousal
reticular formation: plays a role in sleep, arousal, and attention ability
cerebellum
works with the pons; the “little brain;” balance and coordination
limbic system (thalamus, amygdala, hippocampus, hypothalamus)
thalamus: directs [sensory] information from the senses to the cortex.
amygdala (the aggression center): controls fear, anger, and aggression.
hippocampus: involved in the formation of new memories
hypothalamus: regulates body temperature, basic emotions, basic drives, hunger, thirst, sleep, and sex
cerebral cortex (outermost covering of the brain) lobes (4)
frontal: planning movement and working memory
temporal: hearing and advanced visual processing
parietal: bodily sensations
occipital: vision
functions of the cortex (sens, mot, assoc, lang) and language areas (2)
sensory cortex: receives information from touch receptors in the skin
motor cortex: sends impulses to voluntary muscles
association areas: involved in higher mental functioning (75% of the cortex)
language areas: controlled in the left hemisphere
Broca’s area: production of fluent speech
Wernicke’s area: comprehension of speech
