Cranium And The Brain Flashcards
Cranium: anatomy
Cranium:
1. Neurocranium: bony structural container for the brain, protection
- Calvaria
- base
2. Vicerocranium: bony structure to support visceral organs, boundaries
Mandible
Calvaria
Parietal, frontal, superior occipital, and temporal bone
Base
Inferior frontal, temporal, occipital, ethmoid, sphenoid
Sutures
Coronal, Sagittal, lambdoid, and squamous
* dura mater attachment sites inside cranium
Coronal suture
Frontal and parietal - “crown”
Sagittal suture
Inter parietal bones
Lambdoid suture
Parietal and occipital - rainbow
Squamous suture
Parietal and temporal
Pterion
Weakest point of the Neurocranium
Artery: middle meningeal
*epidural hematoma
Pterion: sutures
Sphenosquamous suture
Sphenoparietal suture
Frontosphenoid suture
Cranial fossae: anterior
Frontal bone: frontal crest
Ethmoid bone: crista galli and cribriform plate
Sphenoid bone: lesser wing and anterior clinoid processes *optical canal
Cranial fossae: middle
Sphenoid bone: posterior clinoid process + hypophysial fossa (sella turcica) + greater wing + superior orbital fissure + coratid canal.
- Foramen : rotundum, ovale, spinosum, lacerum,
Temporal bone
Inferior parietal
Cranial fossae: posterior
Temporal bone: petrous part, internal acoustic medius, jugular foreman
Occipital bone: clivus, Internal occipital crest + protuberance, foremen magnum, hypoglossal canal
Inferior parietal bone
Occipital bone: external/inferior
Hypoglossal canal
Foremen magnum
Occipital condyles
External occipital protuberance
Sup/inf nuchal line
Sphenoid bone
Foremen spinosum
Foremen ovale
Medial / lateral pterygoid plates
Temporal bone: ext / inf
Mastoid process/notch
Styloid process
External acoustic medius
Mandibular fossa
Articular tubercle
Coratid canal
Jugular foremen
Stylomastoid foremen
Fissures of the brain
Longitudinal fissure: left and right hemisphere
Transverse fissure: occipital babe and cerebellum
Pterian bones
Frontal, parietal, spheroid, temporal
Telencephalon: neocortex/cerebrum lobes (6)
Frontal, parietal, temporal, occipital, lambic, and insular
Telencephalon: sulci and gyri
Central sulcus: precentral (somatic motor M1) and postcentral (somatic sensory S1)gyrus
Lateral sulcus: primary auditory cortex in temporal
Parietooccipital sulcus
Calcarine sulcus: primary visual cortex
Frontal lobe: function
Somatomotor (M1)
Parietal lobe: functions
Somatosensory (S1)
Temporal lobe: function
Audition (A1)
Occipital lobe: function
Vision (V1)
Limbic lobe:
Drive, emotion, and memory
Insula
Taste
Left hemisphere: functions
Language, function- executing, logic
Right hemisphere
Spatial orientation, emotion, prosody of language
Contralateral control
- Somatic sensory and motor control of neck and body
Right hemisphere controls left side of body
Left hemisphere controls right side of body
Right
Homunculus: medial → lateral
S1: lower limb, trunk, upper limb, face, and mouth
M1: 3 concentric effector regions, 3 cognitive-coordination regions
Deep telencephalon components
Caudate
Nucleus accumbens
Putamen
Globus pallidus
Subthalamic nucleus: diencephalon
Substantial nigra: midbrain
Diencephalon: thalamic family
Epithalamus: pineal gland
Subthalamus: basal nuclei
Thalamus: multiple nuclei
Hypothalamus: multiple nuclei, center of life and death
Optic nerve: CN 2
How many cranial nerves?
12 pairs
CN 1: olfactory nerve
Cribriform plate, ethmoid bone
Bulb: CNS
Nerves: PNS
CN 2: optic nerve
Sphenoid bone
Outlet: Optic canal
CNS
Brain stem layers (3)
Basilar: descending tracts
Tegmentum: ascending tracts, nuclei of CN
Tectum: midbrain only, both descending and ascending tracts
CN 3: oculomotor
Originates at Superior colliculus
Outlet: superior orbital fissure
Oculomotor nerve nuclei : visual pathway
Somatic motor: 5 extraocular muscles
Visceral motor: ciliary ganglion
- ciliary body: lens
- iris with sympathetic
CN 4: trochlear nerve
Outlet: Superior orbital fissure
Only CN from dorsal brain stem
Somatic motor: superior oblique muscle
Midbrain structures
Cerebral peduncle: all axions from and to the cerebral cortex
Substantial nigra
Red nucleus
Cerebra aqueduct: periaquedatal gray
Pons
The “belly” of the brain stem
4th ventricle postcriorly
Mid-pons: CN 5
Pontomedullary junction:
CN 6,7,8
CN 5: Trigeminal nerve
Sphenoid bond
V1: ophthalmic - superior orbital fissure, NFL
V2: maxillary - foreman rotundum
V3: mandibular - for amen ovale
Cutaneous: smell and taste, somatic
Muscular: mastication
CN 6: Abducens
Outlet: Superior orbital fissure:sure, sphenoid bone
Somatic motor: lateral Rectus muscle
CN 7: facial nerve
Sensory:
1. Chemical: taste, anterior 2/3 tongue
2. Somatic: external ear around external meatus
Motor:
1. Somatic: facial expression/stapedius, digastric and stylohyoid, stylomastoid foreman
2. Visceral: parasympathetic
- pterygopalatine ganglia: lachrymal gland/mucosal glands
- submandibular ganglia: submandibular/sublingual salivary gland
What CN originate on the Midbrain? (2)
3 and 4
CN 8: vestibulocochlear nerve
Internal acoustic meatus, temporal bone
Special sensation
- propioception: vestibular division
- hearing: sound wave
**acoustic schwannoma: balance impairment
Medulla oblongata: CN (4)
CN’s: 9, 10, 11, 12
CN 9: glossopheryngeal nerve
Jugular foreman, temporal, and occipital bone
Sensory:
1. Chemical: taste posterior 1/3 of tongue; blood pressure (carotid sinus) and O2 saturation (carotid body)
2. Somatic: mouth and pharynx; middle ear
Motor:
1. Somatic: stylopharynngeus muscle
2. Visceral optic ganglion - parotid gland / mucosal glands
CN 10: vagus nerve
Jugular foreman, temporal, and occipital bones
Sensory:
1. Chemical: taste of epiglottis and palate
2. Somatic: external ear, larynx
Motor:
1. Somatic: pharynx and larynx muscles
2. Visceral: internal organs to end of the midgut (2/3 of the transverse colon)
CN 11: spinal accessory nerve
Jugular foreman
C1-C5, medulla oblongata root back to CN X
Somatic motor: trapezius and SCM muscle
CN 12: hypoglossal nerve
Hypoglossal canal
Somatic motor: extrinsic and intrinsic tongue muscles
Cerebellum: lobes (3)
- Anterior
- Inferior
- Flocculonodular: proprioception and balance
Function: coordination of all CNS functions
Neural communications: cortical regions
Association fibers: Same hemisphere
Commissars: corpus callosum, bilateral hemispheres
Neural communication: cortical and subcortical
Projection fibers and internal capsule
CN with 4 Functional components
7, 9, 10
3 parts of fetal brain
Prosencephalon
Mesencephalon
Rhombencephalon
Prosencephalon
Forebrain
Telencephalon
Diencephalon: optical vesicle of CN 2
Mesencephalon
Midbrain
Rhombencephalon
Hindbrain
Metencephalon
Myelencephalon
Thalamus functions
Relay center for sensory pathways
Coordination cognition, emotion, and motor functions