Lec 9- Brain and Cranial Nerves

six major regions of adult brain

• cerebrum

• cerebellum

• medulla oblongata

• pons

• mesencephalon(midbrain)

• diencephalon

parts of the brainstem

• medulla oblongata

• pons

• mesencephalon(midbrain)

what are meninges

protective membranes wrapping around brain

cranial meninges from most superficial to deep(and space)

• dura mater

• arachnoid mater

• subarachnoid space

• pia mater

where is cerebrospinal fluid found

between the pia and arachnoid layers (in the subarachnoid space)

what is dura mater infoldings functions

like scaffolding, they provide reinforcement and structure

what are the dura mater infoldings

• falx cerebri

• tentorium cerebelli

• falx cerebelli

label the dura mater infoldings(by color)

• blue- falx cerebri

• green- tentorium cerebelli

• pink- falx cerebelli

what are the two main arteries that supply blood to the brain

• vertebral artery

• internal carotid artery

what is the cerebrum responsible for

• control of skeletal muscles, logic, reasoning, planning

• vision, speech, hearing, sensation, processing

major landmarks of the cerebrum and functions

• cerebral hemispheres- two of them

• longitudinal fissure- big separation btn halves; falx cerebri sits here

• corpus callosum- joins the hemispheres

• cortex- gray matter

• gyri(gyrus, singular)

• sulci(sulcus, singular)

4 major lobes of the cerebrum

1. frontal

2. temporal

3. parietal

4. occipital

frontal lobe functions

control of skeletal muscle

parietal lobe function

perception of stimuli related to touch, pressure, pain, vibration, taste, etc

temporal lobe function

perception of auditory and smell stimuli

occipital lobe function

perception of visual stimuli

cerebellum functions

balance, coordination, movement

medulla oblongata functions

processes essentials to survive, especially the cardiovascular system impulses; joins brainstem to spinal cord

think breathing, HR, BP

pons functions

allows for communication between the cerebrum and cerebellum

several cranial nerves emerge here

mesencephalon (midbrain)

motor pathways, alertness, vision and hearing regulation

diencephalon subdivisions

• epithalamus

• thalamus

• hypothalamus

which subdivision of the diencephalon is the pineal gland in

epithalamus

epithalamus components

includes pineal gland; limbic system connection to other brain regions

thalamus components

sensory information relayed here

hypothalamus components

hormonal release; connection between the nervous and endocrine systems

basal ganglia

subcortical(under cerebral cortex), linked structures that control movements of body

limbic system

group of structures that regulate emotions

list limbic structures

• thalamus

• hypothalamus

• hippocampus

• amygdala

• olfactory bulb and tract

what is the ventricular system of the brain

fluid filled spaces and channels that contain and move CSF, help cushion and nourish the brain

CSF makeup

ependymal cells of the choroid plexus

SEQ flow of ventricular system of the brain

1. lateral ventricles in cerebral hemispheres

2. interventricular foramen

3. third ventricle

4. cerebral aqueduct

5. fourth ventricle

how many cranial nerves are there

12 cranial nerves(CNI- CNXII)

as you increase in number, they head farther posteriorly and inferiorly

CN?: sense of smell

CN1, olfactory nerve

CN?:taking in visual information

CN2, optic nerve

CN?: controlling extra-ocular muscles

CN3, CN4, CN6

responsible for controlling the muscles that move the eyeball

CN?: main face nerve

CN5

sensory and motor; skin of face

motor to chewing muscles

aka trigeminal nerve

other name for CN5

trigeminal nerve

other name for CN1

olfactory nerve

other name for CN2

optic nerve

CN?: facial expression and tongue

CN7

motor and sensory; muscles of facial expression; part of tongue, salivary gland

vulnerable during removal of parotid gland

other name for CN7

the facial nerve

CN?: hearing and balance, coordination

CN8

aka the vestibulocochlear nerve

sensory; hearing and balance; damage here can affect these sense; balance and coordination issues associated with this

other name for CN8

vestibulocochlear nerves

divisions of vestibulocochlear nerves

• vestibular division

• cochlear division

CN?:taste and swallowing

CN9

aka glossopharyngeal nerve

sensory and motor; taste and swallowing functions

other name for CN9

glossopharyngeal nerve

CN?: primary heart and digestive

CN10

sensory and motor; primarily heart and digestive regulation through parasympathetic nerve signaling

aka vagus nerve

other name for CN10

the vagus nerve

CN?: neck and back

CN11

motor; neck and back movement

CN?: muscles of tongue

CN12

motor; muscles of the tongue

when affected the tongue will deviate to one side when projected forward

primary vessels that give the brain blood

• internal carotid arteries

• vertebral arteries