W4: the central nervous system Flashcards
what makes up the CNS
brain and spinal cord
main divisions of the brain
cerebrum
cerebellum
diencephalon
brain stem
the cerebrum
responsible for: complex cognitive functions, coordinates the gross automatic muscle movement, voluntary motor movements
largest part of the brain
right and left cerebral hemispheres- folds and convolutions increase the SA
hemispheres are connected via corpus collosum (broad band of white matter) which proves pathway or electrical comms between the two
ridges= gyrus
grooves between ridges= sulcus
deep sulcus= fissure
contains white matter (nerve axons) and grey matter (nerve cell bodies) = white inside, grey outside
areas of the cerebrum
frontal lobe
temporal lobe
occipital lobe
parietal lobe
(name after bones that cover them)
sulcus and gyrus
parietal-occipital sulcus= divides parietal lobe and occipital lobe
central sulcus= divides frontal lobe and parietal lobe
lateral sulcus= divides frontal lobe and temporal lobe
pre central sulcus= contains the main motor cortex of the cerebrum
post central sulcus= contain the main somatosensory cortex (behind central sulcus)
functional areas of the cerebral cortex - frontal lobe
higher mental functions e.g. judgment, concentration, planning
broca’s area- resp for speech
motor function area- resp for eye movement and orientation and initiation of voluntary movement
functional areas of the cerebral cortex- parietal lobe
sensory area- resp for sensation from muscle of skin
somatosensory area- resp for evaluation of temp, texture (helps with object recognition)
functional areas of the cerebral cortex- temporal lobe
wernickes area- written and spoken language comprehension
auditory area- hearing
association area- stm, emotion and equilibrium (keep different sensory inputs in balance and integrated)
olifactory area- smell
functional areas of the cerebral cortex- occipital lobe
visual area- sight, image perception and recognition (processing)
insula
deep to parietal, occipital and temporal
within lateral cerebral sulcus
processing of sensory information
high level cognition
lambic system
has amygdala- resp for fear response
associated with emotions, memory, motivation n smell
branches of brain stem
midbrain
pons
medulla oblongata
midbrain
connects cerebrum to lower parts of brain and spinal cord (cerebral peduncles)
relays motor output
important role in auditory and visual reflexes
superior colliculus- coordinates eye movement in response to visual stimuli
inferior colliculus- movement of head and trunk in reopen to audits simuli
pons
transmits impulses from midbrain to medulla and from one side of cerebrum to the other
with the medulla its important in breathing
medulla oblongata
connects to spinal cord at foramen magnum
sensory input and motor output between brain and spinal cord
function in arousal and consciousness
regulates heartbeat, sneezing, blood vessel diameter, breathing etc
diencaphelon
connects cerebrum with midbrain
around 3rd ventricle
contains hypothalamus, epithalamus and thalamus
diencephalon- hypothalamus
controls and integrates the CNS and pituitary gland
regulation emotions and behaviours
regulation of eating, sleeping and drinking
endocrine function- produces ADH and oxytocin
diencephalon- thalamus and epithalamus
thalamus- provide crude perception of pain and involved in movement planning and control
epithalamus- consists of pineal gland (melatonin) and habenular nuclei
cerebellum
2 hemispheres
integration of sensory perception and motor output
constant feedback on body position allows fine movement
cognitive function, attention n processing language etc
structure of spinal cord
elongated part of the CNS in vertebral canal
surrounded by meninges and CSF
white matter and grey matter- white (axons) and grey (cell body)
cranial meninges
surround brain and spinal cord
protect, support and circulate CSF
consist of 3 layers of CT: dura, arachnoid and pia
subarachnoid space is where CSF is filled
cranial meninges- dura mater
outermost and strongest of the membranes
is a double layer which is fused together except where it separates to enclose the dural venous sinuses
outer layer attaches to inner surface of skull (peritosteal layer)
inner meningeal layer has reflection and infoldings which form structures: separates the 2 hemispheres, separates hemispheres from cerebellum and separates cerebrum from cerebellum
sensitive to stretching= headaches
cranial meninges- arachnoid mater
delicate, impermeable and avascular membrane
between dura and pia
separated by subdural space (dura mater) and subarachnoid space (pia mater)
blood can accumulate following trauma in these spaces
cranial meninges- pia mater
inner most layer
delicate matrix bearing vessel which cover surface of brain
impermeable to fluid
