chpt 4. CNS Flashcards
day 28 aka 4 weeks embryo structures
-forebrain, hind brain, mid Brain
day 42 embryo
Brain structures have developed
day 77 embryo
cerebrum is developed and other structures
Brain after birth
continues to develop till 5-7
nervous system organization
cns and pns
function classes of pns neurons
afferent and efferent
afferent nerves function
carry info to cns via peripheral axons
efferent nerves function
take away info from cns and bring to effector
which nerves name up the autonomic and somatic ns?
efferent nerves
what nerve is attached to a receptor
afferent nerve
location of interneuron
cns
interneuron function
learning, motivation, memory, transfer signals
which neuron is the most abundant
interneuron
neuroglia or glial cells function in pns
- make myelin (Schwann cells), support cell body (satellite cells), nourishing factor (neurotrophic)
overall function of neuroglia or glial cells in cns
provide physical, metabolic and function support
4 major neuroglia or glial cells in cns
- astrocytes
- oligodendrocytes
- microglia
- ependymal cells
Astrocytes function
-create blood brain barrier (bbb)
-neurotrophic
physical support
-fetal brain development
-neural scar tissue
-synthesize neurotransmitters
-ion balance
-enhance and strengthen synaptic transformation
Astrocytes structure
star shaped
oligodendrocytes function
produce myelin stealth in CNS
microglia function
scavengers
dementia
over excitation of microglia
Ependymal cells function
- line inter cavities of brain and spc
- contribute to cerebrospinal fluid
- serve as neural stem cells
which cells form neuroblastoma. gliomas
Ependymal cells
protection of cns
- cranial bones
- meninges
- csf
- bbb
meninges layers
- dura mater
- arachnoid mater
- pia mater
cauda equina
- individual nerves can be seen
- epidural administered
- cfs withdrawn
how many cervial nerves pairs are in the spc
8
how many thoracic nerves pairs are in the spc
12
how many lumbar nerves pairs are in the spc
5
how many sacral nerves pairs are in the spc
5
how many coccygeal (tailbone) nerves pairs are in the spc
1
dermatomes function
allows physicals to determine where spc could be damaged
dorsal root function
-brings in afferent afferent fiber + sensory info
ventral root function
-brings in efferent fibre motor
white matter function
-carries info to and from brain
dorsal root ganglion
- foreign particles hide here
- cell bodies of afferent neurons are there
grey matter contains
- dorsal horn
- lateral horn
- ventral horn
dorsal horn function
-cell bodies of interneurons on which afferent neurons terminate
lateral horn function
-cell bodies of autonomic efferent nerve fibers present
ventral horn function
-cell bodies of somatic efferent neurons
what does the csf flow through ?
-central canal
Schwann cell location
pns
satellite cell location
pns
Schwann cell functions
-make myelin sheath
axon rejuvenation
dura mater function
-forms dural and venous sinuses
dura mater structure
- tough
- closet to cranial bone
dural and venous sinuses
- blood filled cavity’s
- blood empties to return to heart
arachnoid mater structure(s)
- cobweb like, networks
- subarachnoid and arachnoid villus
pia mater structure
- closest to brain
- gentle
- highly vascular
pia mater function
nourishes
meningitis
inflammation of meninges, can die within 24 hours, lets invaders in
csf structure
salty, ions, vitamins
where is csf formed?
choronid plexus of ventricles 3&4 cavities
what forms csf?
ependymal cells
csf function
- allows brain to float
- cushions brain and spc
- allows exchange of materials
flow of csf
chorioid plexus -> ventricles -> subarachnoid -> venous blood
how many times is csf formed
3 times day
blood brain barrier function
- isolates brain from harmful things
- exchange
- parkinson
where is BBB not present ?
- medulla oblongata
- hypothalamus
what is function of having no BBB in medulla oblongata ?
-allows puking
what is function of having no BBB in hypothalamus?
-link b/w NS and endocrine system
cerebral cortex structure
-largest- 80% of Brain weight
incovulated,
suli,
gyris
incovualtes in cerebral cortex function
increase surface area
what joins and allows communication the two hemispheres of the cereal cortex?
corpus callosum
left cerebral hemisphere function
-logical, analytical, sequential and verbal skills
right cerebral hemisphere function
- non-verbal/ language skills
- artistic
- holistic
- left handed
4 lobes of cerebral cortex
- occipital
- parietal
- frontal
- temporal
occipital lobe function
visual input
parietal lobe function
- sensory input
- receives and process sensory input
frontal lobe function
- voluntary movements
- higher level thinking
- language, speech, thought
temporal lobe function
-hearing/ sound sensation
central sulcus function/ location
-separates frontal and parietal lobe
-posterior frontal lobe
anterior parietal lobe
grey matter layers + structure
6, has cell bodies of neurons
white matter layers + structure
single, myelinated axon carrying messages
primary motor cortex function
- voluntary control over movement
- controls muscles on opposite side of body
primary motor cortex location
frontal lobe
homunculus
bigger the organ, the more devoted to the muscle
-unequal and upside down
somatic sensory cortex location
- anterior parietal lobe
- posterior central sulcus
somatic sensory cortex function
- sensory info is projected here
- sensations arrive here
proprioception meaning
- body in present time
- awareness of body position
supplementary motor area function
programs complex movements
supplementary motor area location
frontal lobe, anterior primary motor cortex and posterior premotor cortex
premotor cortex function
- coordination of complex movement
- moving body+ arms towards smt
premotor cortex location
frontal lobe, anterior supplementary motor cortex
-posterior prefrontal association cortex
prefrontal association cortex function
- decision making
- personality + working memory
- plan for voluntary activity
prefrontal association cortex location
frontal bone, forehead
brocas area location
frontal lobe
brocas area function
form speech
what area is damaged in expressive aphasia
damage to brocas area
expressive aphasia result
jumbled speech, don’t make sense
Receptive Aphasia area damages is
wernickes area
result of receptive aphasia
can’t understand language
parts of Brain involved in working memory
- parterital-temporal-occipital
- limbic association cortex
- pre-frontal
primary auditory cortex function
processes hearing
primary auditory cortex location
temporal lobe
limbic association cortex function
memory, motivation and emotion
limbic association cortex location
inner and bottom surface of temporal lobe
primary visual cortex function
sight
primary visual cortex location
base of occipital lobe
what cortex integrates all sensory input and is important in language?
parietal-temporal-occipital association cortex
wernickes area location
b/w pariteal and temporal
wernickes area function
understand/ comprehend speech
posterior partial cortex function
- intergration of somato-sensory and visual input
- important for complex movements
Basal Nuclei components
- 4 nuclei with masses of grey matter
function of basal nuclei
- select and maintain purposeful movements
- help monitor contractions for support and posture
- inhibit muscle tone
muscle tone meaning
-ability of muscle to stretch, relax and change in direction
what allows the needed movement initiated by basal nuclei?
basal nuclei forming a loop with thalamus and high cortex
disease associated with damage to Basel nuclei
parkinsons
huntingtons
ocd
tourettes
Parkinson’s signs and symptoms
see unwanted movements, hip shuffling, staring, slow in movement
how does one get Huntington’s disorder
genes
huntingtons signs and symptoms
- lost motor co-ordination
- twitching
- dementia/ congintion loss
cerebellum is also known as
the 2nd or little brain
cerebellum overall function
-planning and executing voluntary movement s
what is the second largest structure in the Brain?
cerebellum
cerebellum breaks down into
- vestibuocerebellum
- spinocerebellum
- cerebrocerebellum
vestibuocerebellum function
- eye movement
- balance
- muscle tone
-skilled voluntary movements
are functions of
spinocerebellum
cerebrocerebellum is responsible for
- planning and initiating voluntary movement s
- stores repeptitive/ procedural memeories site
diencephalon components
thalamus
hypothalamus
thalamus function
the relay station of the brain that is the site of sensory processing
what sensory thing does the thalamus not process
smell
where is smell processed
parietal lobe
what structure is aware of everything in body but cant control things
thalamus
what structure can direct attention to stimuli of specific interest
thalamus
hypothalamus location
below thalamus
what structure links the endocrine and nervous system
hypothalamus
function of hypothalamus
- tell glands to release hormones
- regulates body activity
what type of body activity does the hypothalamus regulate
- eating and drinking behaviors
- flight and fight
- body temperature
what is released during fight and flight
catecholamines
what glands are controlled by the hypothalamus
pineal and pituitary gland
pineal gland function
-controls day and night cycle in circadian rhythms
what gland seceretes melatonin
pineal gland
anterior pituitary function
- growth
- reproduction
- metabolism
which pituitary is used every day and is the true endocrine gland?
anterior
what hormone and gland allows release of ovum and sperm
anterior pituitary and gonadotrophic hormone
what pituitary is responsible for mammary gland development
anterior pituitary
the function of the posterior pituitary
- oxytocin release
- vasopressin
function of oxytocin
- bonding
- milk ejection
- cervical and uterine contractions
vasopression function
- anti-diuretic
- governs kidney
- body fluid maintained
- regulates blood pressure
neural plasticity function
the ability of neurons to change based on demands placed on it
why can some areas of the brain resume activity for a part of the brain that was damaged?
neural plasticity
where are the ascending and descending nerves located on the spinal cord
white matter
where are horns located in the spinal cord
grey matter
where are axons of neurons located in the spinal cord
white matter
what makes the brain aware of things in the spc
white matter
-fingers
-thumb
-jaw
-muscles used with speech: lips and tongue
are exaggerated in which homunculus and why
- indicate fine degree of motor control these body parts have
- motor homunculus
which lobe is the motor homunculus located in?
frontal
where is the sensory homunculus located?
parietal lobe
what are somaesthetic sensations
heat, cold, pain, tough pressure
what lobe detect somaesthetic sensations ?
parietal
which organs have more devotion in the sensory homunculus?
- face
- tongue
- hands
- genital
do hemisphere and cortex receive info from different sides of the Body?
yes
what localizes sensory info in the body?
somatosensory cortex
what makes a person aware of change In senses (hot vs cold)
thalamus
brain stem components
- medulla oblongata
- pons
- mid brain
overall function of brain stem
control circulation, digestion, respiration
function of medulla oblongata
- centre for vomiting
- governs respiratory sys
- blood pressure regulation
- heart rate
what brain stem structure is also known as the little bridge
the pons
which brain stem structure is present in early fetal development
midbrain
function of the pons
- eye movement
- neural pathways that carry info b/w parts of the forebrain and the midbrain
midbrain function
- reflex eye movement
- equilibrium (vestibular apparatus)
what contributes to Reticular Activating system
the brainstem
Reticular Activating system function
- governs everyday needs
- controls many things
what does the RAS control
- BP
- respiratory sys
- stretch reflex
- pain
- sleep and arousal cycles
where is the site of 12 cranial nerves
RAS + spinal cord
name of CN1
olfactory nerve
which nerve is the optic nerve
CN2
name of CN3 nerve
oculomotor nerve
CN3 function
controls eye muscles
CN1-3 location
head and neck region
CN10 name
vagus nerve
what is different abt the CN10
it leaves the head and enters the intrabdominal region
controlling blood pressure is the function of which cranial nerves
vagus/ CN10 nerve
which cranial never goes to the heart and taste buds
vagus/ CN 10 nerve
limbic systems components
- amgydala
- hypocampus
- fonix
- cingulale gyrus
limbic system location
deep inside brain
overall functions of the limbic system
- emotion
- motivation
- behaviour
- learning
- survival tings (in born behavioural patterns)
which limbic centre component controls fear, nervousness, goosebumps, sex drive
amygdala aka systemic response
which limbic centre structure has 22 regions
amygdala aka systemic response
fornix function
- overall unknown
- connects hypocampus w/ thalamus
- thalamas with higher cortex
which limbic centre component is used for expressing emotions with gestures
-cingulale gyrus
which region do you cut off so you can’t recall memories
fornix
hippocampus function
- declarative memory
- new neurons are created
what is lost in Alzheimer’s patients
hippocampus
