HAN312 lec6 nervous system & special senses

nervous system functions

carries impulses between the brain, neck, head, and spinal nerves

releases chemicals called neurotransmitters

controls voluntary and involuntary bodily functions

central nervous system (CNS)

brain and spinal cord

peripheral nervous system (PSN)

nerves throughout the body, cranial nerves, spinal nerves, autonomic nervous system (ANS)

autonomic nervous system (ANS)

involuntary bodily functions, sympathetic vs parasympathetic nervous system

sympathetic nervous system

part of ANS, influence bodily functions during times of stress

parasympathetic nervous system

part of ANS, heart rate, breathing, GI tract muscles

cerebrum

largest and uppermost portion of the brain, divided into right and left halves (cerebral hemispheres) and subdivided into lobes, cerebral cortex, gyrus, sulcus

cerebral cortex

surface nerve cells, gray matter, controls higher mental functions (speech, vision, smell, movement, hearing, and thought) 

gyrus

raised convolution on the surface of the cerebrum 

sulcus

groove or fissure on the surface of the brain 

frontal lobe

front portion of the cerebrum that controls voluntary muscle movement and is involved in emotions, Broca area

occipital lobe

back portion of the cerebrum that control vision

parietal lobe

middle-top portion of the cerebrum involved in perception of touch, temperature, and pain

temporal lobe

portion of cerebrum below the frontal lobe, controls senses of hearing and smell as well as memory, emotion, speech and behavior, Wernicke area 

diencephalon

hypophysis, responsible for directing sensory information to the cortex, area deep within the brain that contains the thalamus, hypothalamus, and pituitary gland

thalamus

integrates and monitors impulses from the skin, i.e. pain

hypothelamus

controls body temp, sleep, appetite, sexual desire, and hormones (released from the pituitary gland)

cerebellum

hindbrain, posterior portion of the brain, coordinates the voluntary muscles and maintains balance 

brainstem

connects the brain to the spinal cord, assists in breathing, heart rhythm, vision, and consciousness, midbrain, pons, medulla oblongata 

midbrain

mesencephalon, uppermost part of brainstem that connects the brainstem to the cerebellum, controls sensory processes

pons

bridges cerebrum and cerebellum with the rest of the brain, houses nerves for face and eyes

medulla oblongata

part of the brainstem that connects the brain and the spinal cord, controls respiration, heartbeat, and blood vessel size

ventricle

one of the 4 interconnected cavities within the brain that contain and secrete cerebrospinal fluid

cerebrospinal fluid (CSF)

colorless fluid that circulates in and around the brain and spinal cord, acts as a protector and transports nutrients

meninges

membranous covering of the brain and spinal cord, dura mater, arachnoid, pia mater

dura mater

strong fibrous outermost layer of the meninges, subdural space under

arachnoid

delicate fibrous membrane forming the middle layer of the meninges, subarachnoid space under 

pia mater

thin inner layer of the meninges that attaches directly to the brain and spinal cord

spinal cord

portion of the CNS contained in the spinal or vertebral canal, responsible for nerve conduction to and from the brain and the body, begins at the brainstem and ends at the 1st and 2nd lumbar vertebrae, culminating in the cauda equina (horse tail)

neurons

individual nerve cells that make up the basic structure of the nervous system and conduct impulses

anatomical portions of a neuron

dendrite, cell body, nucleus, axon (myelin sheath), terminal end fibers (secrete neurotransmitters across synapse)

ganglion

group of nerve cell bodies located along the pathway of a nerve

plexus

interlacing network of nerves

neurotransmitters

chemical messenger released into a synapse by a neuron, either stimulates or inhibits another cell

sensory nerves

afferent, carry messages toward the brain 

motor nerves

efferent, carry messages away from the brain

mixed nerves

carry both sensory and motor fibers

dorsal root

carry sensory impulses toward the spinal cord/brain

ventral root

carries motor impulses away from the spinal cord/brain to muscles or glands

cranial nerves

12 pairs of nerves that emerge from the cranium, olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, hypoglossal

olfactory nerve

I, sense of smell

optic nerve

II, vision 

oculomotor nerve

III, controls eye movement (up, down, medial, and pupil constriction)

trochlear nerve

IV, controls superior oblique eye movement (downward and outward eye movement)

trigeminal nerve

V, sensory (face, teeth, sinuses) and motor (chewing muscles)

abducens nerve

VI, controls lateral rectus eye muscle (outward eye movement)

facial nerve

VII, facial expressions, taste, and tear and salivary gland function

vestibulocochlear nerve

VIII, hearing and balance

glossopharyngeal nerve

IX, taste, swallowing, salivation

vagus nerve

X, controls heart rate, digestion, speech

accessory nerve

XI, controls neck and shoulder muscles

hypoglossal nerve

XII, controls tongue movements

spinal nerves

31 pairs that emerge from the spine

neuroglia/glia cells

cells that support and protect nervous tissue, do not transmit impulses

glia cells CNS

astrocytes, oligodendrocytes, ependymal cells, microglia

glia cells PNS

satellite cells, Schwann cells

astrocytes

provide structural (blood brain barrier) and metabolic support, repair cells

oligodendrocytes

myelinate axons and insulate electrical impulses

ependymal cells

produce and moves cerebrospinal fluid (CSF)

microglia

defense and immune response

satellite cells

provide structural and metabolic support for cell body of neurons

Schwann cells

myelinate axons and insulate electrical impulses

combining form gray

poli/o

combining form sensation, perception

esthesi/o

combining form speech

phas/o

combining form word, phrase

lex/o

combining form muscle

my/o

combining form movement

kines/o

combining form order, coordination

tax/o

combining form entire brain

encephal/o

combining form skull

crani/o

combining form head

cephal/o

combining form cerebrum

cerebr/o

combining form cortex

cortic/o

combining form thalamus

thalam/o

combining form cerebellum

cerebell/o

combining form pons

pont/o

combining form meninges

mening/o, meningi/o

combining form sheath (referring to meninges)

thec/o

combining form hard, dura mater

dur/o

combining form ventricle

ventricul/o

combining form spine

spin/o

combining form vertebra

spondyl/o

combining form spinal cord, bone marrow

myel/o

combining form ganglion

gangli/o, ganglion/o

combining form glue, neuroglia

gli/o

combining form few, scanty

olig/o

combining form nerve

neur/o

combining form nerve root

radicul/o

combining form vagus nerve

vag/o

prefix half

hemi-

prefix on, following

epi-

prefix above, excessive

hyper-

prefix below, deficient

hypo-

prefix beside

para-

prefix many, much

poly-

prefix four

quadri-

suffix mind

-phrenia

suffix speech

-phasia

suffix movement

-kinesia, -kinesis, -kinetic