Anatomy Exam 3

central nervous system contains the

brain and spinal cord

rostral

towards the nose

caudal

towards tail

gyri

lump bump wrinkle

sulci

space between gyri

nuclei

sites where cell bodies congregate

tracts

bundles of axons in the CNS

spinal cord

pathway for sensory impulses traveling to the brain, motor impulses traveling from the brain to the skeletal muscles or other effectors, and controls rapid reactions to environmental changes (reflexes)

brain

main control center where thoughts and behaviors are initiated and where memories are stored

dura mater

toughest outer layer

pia mater

delicate innermost layer

3 layers of the meninges

dura mater, arachnoid mater, pia mater

cerebral spinal fluid

maintains ionic balance and keeps brain buoyant

what is the epidural space

space between vertebra and spinal cord

what fills the epidural space

fat

what fills the subdural space

nothing

what fills the subarachnoid space

CSF

falx cerebri

separate 2 hemispheres of cerebrum

falx cerebelli

separates 2 hemispheres of the cerebellum

tentorium cerebelli

separates the cerebrum from the cerebellum

diaphragma sellae

support anterior cerebrum to prevent crushing the pituitary gland

tentorial incisure

an opening in the anterior portion of the tentorium cerebelli that allows the brainstem to pass through

where does the brain get its blood from and what drains it

internal carotid artery and the vertebral arteries

internal jugular vein and dural sinuses

blood brain barrier

keeps toxic elements and pathogens in blood out of the brain but lets the good stuff in

ascending tracts

carry sensory information from the rest of the body to the brain for interpretation

first order neurons

have their somas in the dorsal root ganglion of the spinal cord

second order neurons

have their cell bodies in the dorsal columns of the medulla of the spinal cord

third order neurons

have their cell bodies in the thalamus of the brain

descending tracts

carry motor information form the brain to the effectors in the periphery

paraplegia

2 limbs affected- only lower limb paralysis

quadriplegia

4 limbs affected- upper and lower limbs

hemiplegia

2 limbs affected- sided right upper and lower

paresis

weakness while retaining some functionality

brainstem location

the junction between the brain and spinal cord

brainstem fucntion

contains both tracts and nuclei and acts as a relay center for motor and sensory reflexes for vision hearing and also governs reflexes vital to life

midbrain special senses

vision and hearing

midbrain fucntion

maintaining circadian rhythms, monitoring and controlling sleep/wake cycles, and temperature regulation

Pons function

relay for voluntary movement from the cerebral cortex to the cerebellum

conducts sensory impulses to higher brain areas

conducts motor impulses to the spinal cord

pneumatic and apneustic areas of the pons

nuclei that work with the medullary rhythmicity area to help control breathing

medulla oblongata: cardiovascular center

heart rate, blood pressure

medulla oblongata: medullary rhythmicity area

regulate breathing

cerebellum

located caudally and inferiorly to the brain, it has a highly folded surface which helps increase its surface area of outer grey matter cortex. vastly greater number of neurons

cerebellum function

evaluate, smooth, and coordinate contractions of the skeletal muscles and also help maintain posture and balance

Limbic system

includes parts of the cerebrum and diencephalon, it encircles the upper brainstem and corpus callosum in a place called the cingulate gyrus

Limbic system function

control our emotional behavior, helps sort the feelings of pleasure pain rage anger and affection

diencephalon

a central core of the brain tissue extending between the brainstem to the cerebrum, it surrounds the third ventricle.

thalamus

involved in a wide variety of sensory and motor signal processing and acts as a go between for the higher and lower brain centers

relays and processes sensory impulses to the primary sensory areas of the cerebral cortex (directs traffic), it also transmits input from the primary motor area of the cerebral cortex

hypothalamus

lthe major communication and translation relay center between the nervous and endocrine systems, it connects to the pituitary gland via the infundibulum

one of the major regulators of whole body homeostasis

pineal gland (epithalamus)

located in the caudal part of the diencephalon and is in charge of secreting melatonin, has a large part in maintaining our circadian rhythms (biological clock)

cerebrum

large mass of nervous tissue which is housed in the cranial cavity

basal nuclei

act as motor proofreaders, act with the cerebellum to fine tune the types of movements initiated by the cerebral cortex.

sensory areas

allows for perception (conscious awareness) of sensory information

motor areas

controls the execution of voluntary movements

association areas

concerned with more complex integrative functions such as memory personality traits emotions and intelligence

primary somatosensory area

general touch

primary visual area (cortex)

special sense (vision)

primary auditory area (cortex)

special sense (hearing)

primary gustatory area (cortex)

special sense (taste)

primary olfactory area

special sense (smell)

primary motor cortex/area (precentral gyrus)

voluntary motor action

broca’s area

production of vocal language

somatosensory association area

puts touch into context for memory

visual association area

puts visual stimuli into context for memory

auditory association area

puts audible stimuli nto context

wernicke’s area

understand and produce coherent speech

prefrontal cortex

executive function/ personality inhibitors

premotor cortex

motor planning/ muscle memory

association tracts

connecting 2 nuclei in the same hemisphere

commissural tracts

connecting the 2 hemispheres (largest commissural tract is the corpus callosum)

projection tracts

takes info from rostral parts of the brain to caudal parts

touch

general sense, the translation of physical contact into our perception of that contact

receptive field

the area served by any one neuron

smell

special sense, in charge of sensing the presence of odorant chemicals in the environment and in food

olfactory epithelium

(olfactory cells embedded within the nasal mucosa) lining the superior aspect of the nasal cavity is specialized to respond to the odorant chemicals in the air we breathe

taste

special sense, in charge of sensing the presence of biomolecules and tastant chemicals in food

lingual papillae

bumps on the surface of the tongue which are covered in taste buds

taste buds

are specialized structures full of taste cells that react to those tastant chemicals to cause depolarization of associated neurons to communicate flavors to the brain

hearing

the translation of sound waves (in the form of vibrations) into a perception of the noise

vestibular sense

allows us to determine which direction you are traveling

vision

special sense, in charge of translating light waves as they are reflected off of something into perception of an image

what muscle allows the eyelids to remain open all day

levator palpebrae superioritis

what is conjunctivitis

pink eye

retina

the inner lining of the back of the eye, has specialized cells designed to translate light waves into action potientials for the brain to interpret

rods

produce images in shades of gray

cones

responsible for color vision

endoneurium

over one axon

perineurium

over a fascicle of neuron

epineurium

over entire nerve

order of cranial nerves

olfactory

optic

oculomotor

trochlear

trigeminal

abducens

facial

vestibulocochlear

glossopharyngeal

vagus

spinal accessory

hypoglossal

olfactory nerve

carries impulse from odor receptors within olfactory epithelium in the nasal cavity

pass through olfactory foramina in cribriform plate of ethmoid bone

synapse in olfactory bulbs with neurons of olfactory tract

end in primary olfactory cortical are of the cerebral temporal bone

optic nerve

carries impulses from rods and cones in the retina of the eye

passes through optic foramen in the orbit

merge to form the optic chiasm and then splits to form the optic tract

optic tracts end in primary visual cortical area of the cerebral occipital lobes

oculomotor

move the eye, detect where the eye is in space (proprioception)

carries somatic motor impulses to four muscles of the eye and upper eyelid

superior and inferior rectus

inferior oblique

medial rectus

levator palpelorae superios

autonomic motor axons adjust shape of lens and size of pupil

trochlear nerve

some axons for proprioception associated with muscles of the eye

carries somatic motor impulses to the superior oblique muscles to move the eye

trigeminal nerve

somatosensory impulses from scalp, face, and mouth, for touch, pain, and temperature

somatic motor impulses to the muscles of mastication and tiny muscles in the middle ear

trigeminal division 1

ophthalmic-forehead to nose

trigeminal division 2

maxillary- upper lip to anterior ear

trigeminal division 3

ear and lower jaw

Abducens nerve

carries somatomotor impulses to the lateral rectus muscle to move the eyelid laterally

abducts the eye

facial nerve sensory

taste and 2/3 of the tongue

facial nerve motor

facial expression