Chapter 15 - Brain/Cranial Nerves Flashcards
5 major regions of the brain
- cerebrum
- diencephalon
- mesencephalon
- metancephalon
- myelencephalon
brain development at 4 weeks
prosencephalon: forebrain
mesencephalon: midbrain
rhombencephalon: hindbrain
brain development at 5 weeks
prosencephalon
- telencephalon
- diencephalon
mesencephalon
- mesencephalon
Rhombencephalon
- metaencephalon
- myelencephalon
gyrus (gyri)
risen portion
sulcus (sulci)
areas of depression
telencephalon (cerebrum)
grey matter
neuron cell bodies
(processes info and decides how to proceed)
telencephalon (cerebrum)
cerebral cortex
covers surface
telencephalon (cerebrum)
cerebral (basal) nuclei
oval clusters of grey matter
telencephalon (cerebrum)
white matter
axons
(carry info from one place to another)
telencephalon (cerebrum)
cerebral hemispheres
separated by a deep longitudinal fissure
“midsagittal plane”
telencephalon (cerebrum)
corpus callosum
bundle of axons forming a tract linking the two hemispheres
“communication”
frontal lobe
- anterior
- ends at central sulcus
- voluntary motor functions, concentration, verbal communication, decision making, planning, and personality
parietal bone
- lies between the central sulcus and the parieto-occipital sulcus
- contains the postcentral gyrus
- sensory function, evaluation of shape and textures
temporal lobe
- lies under temporal bone
- hearing and smell
occipital lobe
- posterior region
- processing visual information and storing of memories
insula lobe
- found underneath the temporal lobe
- taste and memory
functional areas of frontal lobe
primary motor complex
(precentral gyrus)
controls voluntary skeletal muscle (left hemisphere controls right side of body)
functional areas of frontal lobe
broca area
motor speech area
left frontal lobe
functional areas of frontal lobe
frontal eye field
anterior to the primary motor cortex, coordination of eye movement
functional areas of parietal lobe
primary somatosensory complex
(postcentral gyrus)
receives information from touch, pressure, pain, temperature
functional areas of occupital lobe
primary visual cortex
recieves and processes visual information
wernickle area
understanding + comprehension of spoken and written language
diencephalon
thalamus
- recieves sensory impulses from all the senses except olfaction
- relays the information to the primary somatosensory cortex
diencephalon
hypothalamus
major control center of:
* circadian rhythm
* automatic nervous system
* endocrine system
* emtional state
* food and water intake
metencephalon
pons
- anterior part of the brainstem
- houses sensory and motor tracts connecting the brain and spinal cord
cerebellum
- receives information about torso position and balance
- fine tunes skeletal muscle movement
(helps us stay upright)
myelencephalon
medulla oblongata
- communication
- all tracts either ascending or descending between the brain and spinal cord run through
- connection to spinal cord
3 different types of protection
- meninges
- cerebrospinal fluid
- blood-brain barrier
meninges
3 protective connective tissue layers that stabilize and cushion the soft tissues of the brain from the bones of the skull
describe the 3 layers of the meninges
pia mater: innermost, adheres to the brain
arachnoid mater: middle layer, comprised of collagen and elastic fibers
dura mater: 2 tough fibrous layers
define cerebrospinal fluid
describe 3 functions
clear liquid that circulates around the brain and spinal cord
1. buoyancy: allows it to float and not crush under its own weight
2. protection: movement buffer
3. environment stability: transports nutrients and chemicals to the brain and removes waste
blood brain barrier
- limits and regulates what substances can enter into the interstitial fluid of the brain and cerebrospinal fluid
- lipid soluble components - alcohol, nicotine can readily pass
2 main “players” in the blood-brain barrier
- astrocytes: perivascular feet, contain enzymes
- tight junctions: between the endothelial cells, tightly packed like traffic
meningitis
- bacterial or viral
- fever, headache, vomiting, STIFF NECK
- respiratory droplets
antibodies are too large to pass through the blood-brain barrier
hydrocephalus
CSF blockage
kids: sutures arent fused so the skull will expand
adults: fluid presses inward (brain damage)
treatment: shunt with drain
parkinson’s disease
- deficiency in the neurotransmitter dopamine
- degeneration of neurons in the brain
- SHUFFLING GAIT, stiff posture, slow movement
- slow progessing
epilepsy
- recurring motor, sensory or psychological malfunction
- neurons firing at unpredictable times/rates
- with/without convulsive movements
olfactory nerve
CN I
smell
optic nerve
CN II
vision
oculomotor
CN III
upper eyelid, extrinsic eye muscles
trochlear nerve
CN IV
1 extrinsic eye muscle
Abducens nerve
CN VI
muscle that pulls eye laterally (abduction)
trigeminal nerve
CN V
sensory nerve to face
muscles of mastication
facial nerve
CN VII
motor nerve to face
bells palsy
vestibulocochlear nerve
CN VIII
balance
hearing
glossopharyngeal nerve
CN IX
taste and swallowing
vagus nerve
CN X
sensory and motor to internal organs
“rest and digest”
accessory nerve
CN XI
assess weakness or paralysis of neck muscles
hypoglossal nerve
CN XII
move tongue