CNS

Brain

Lobes

frontal

Structures

Precentral gyrus

Primary motor cortex

Brocas area (left side)

speech production

Brocas aphasia

Functions

Executive function

motor movement

impulse control

Parietal

Structures

Post central gyrus

Primary somatosensory cortex

Wernickes extends into inferior paietal

Lateral ventricles

Where CSF is made

CSF made from choroid plexus

Flow of CSF through the brain:

1. Lat ventricles

2. Interventricular foramina

3. 3rd ventricle

4. Cerebral aquaduct

4th ventricle

5. Spine

6. Back to blood

Functions

Spatial information or proprioception

Somatosensory info: Pain, touch, pressure, temperature, vibration

Subtopic

Temporal

Structures

Wernickes area(left side)

Speech comprehension

Sylvian(lateral) fissure

Heschells gyrus

Primary auditory cortex

Auditory association area

Functions

memory

Auditory processing

Language comprehension

Occipital

Structures

Parieto occipital sulcus

Secondary visual cortex

Primary visual cortex

Cuneus

Lingual gyrus

Calcarine fissure (medial occipital lobe)
*seperates cuneus and lingual gyrus

Functions

Visual perception

Spatial reasoning

eye movements

Insula

Structures

Gustatory cortex

Functions

Taste

Emotional processing

risk reward

Sensorimotor processing

Embryonic Development

Stages

Pre embryonic

Conception to day 14

embryonic disk forms(ectoderm, endoderm)
mesoderm forms toward end of stage

Embryonic

day 15 to week 8

Endoderm develops into

Gut, liver, pancreas, respiratory system

Ectoderm develops into

sensory organs

nervous system

Epidermis

Mesoderm develops into

Muscles, skeleton, excretory and circulatory systems

Stage 2 development

Sclerotomes

Bones

myotomes

Muscles

Dermatomes

Skin

Formation of neural tube occurs

If it DOES NOT close

Spina bifida

Tube -->CNS

Crest--> PNS

Fetal

End of week 8 to conception

Myelination takes place

Brain development

prosencephalon(forebrain)

Telencephalon

Cerebral hemispheres, cerbral cortex, basal ganglia

Lateral ventricles

Diencephalon

thalamus, hypothalamus, epithalamus, retina

third ventricle

Mesencephalon(midbrain)

Mid brain (brain stem)

cerebral aquaduct

Rhombencephalon(hind brain)

Metencephalon

cerebellum , pons

fourth ventricle

Myelencephalon

Medulla oblongata

fourth ventricle

Protection

Skull

Viscerocranium

Maxilla, mandible, zygomatic bones, lacrimal bones, nasal conchae

Neurocranium

Ethmoid, frontal, occipital, parietal, sphenoid, temporal

Fossa

Anterior fossa

CN 1, CN2

Middle fossa

superior orbital fissure

Houses CN 3,4,V1, 6

Rotundum

CN v2

Spinosum

CNV3

Posterior fossa

Internal acoustic meatus

Houses CN 7,8

Jugular foramen

Houses CN 9,10,11

Blood supply

main arteries supplying the brain

Vertebral arteries

Internal carotid artery

Anterior circulation(4)

ACA, ICA,ACOMM,MCA

Posterior circulation(7)

PCOMM, PCA, Basilar, SCA, AICA, PICA, vertebral

Circle of willis(6)

ACA, ICA, MCA, ACOMM, PCA, PCOMM

ACA feeds

Medial frontal and parietal lobes, part of the basal ganglia

MCA feeds

Basal ganglia, lateral inferior frontal, parietal, inferior temporal)

PCA feeds

Medial inferior temporal and occipital lobe, thalamus and hypothalamus

Cranial nerves

Oh

Olfactory(Sensory)

F: Smell
Fo: Olfactory foramina

Connects to reticular formation, and amygdala

once

Optic(sensory)

Supplies: Photoreceptors
F: Vision, light reflex
Fo: optic canal

Pathway

eye --> Nerve --> Optic chiasm--> Optic tract--> Lateral geniculate body

one

Oculomotor(Motor)

Supplies: eye muscles
Involved with: Tecto spinal tract
F: Controls pupil size
FO: Superior orbital fissure

takes

Trochlear(motor)

Only one that starts in dorsal view
Supplies: Superior oblique
F: Eye movement
FO: Superior orbital fissure

the

Trigeminal (Both sensory and motor)

Supplies: Muscles of mastication amongst others
F: Sensation of pain, Blink reflex(corneal)
V1 Fo: Sup orbital fissure
V2: Fo: Foramen rotundum
V3 Fo: Foramen ovale

V1: Opthalamic

V2: maxillary

V3: Mandibular

anatomy

Abducens(motor)

Supplies: Lateral rectus
F: Eye movement
Fo: Superior orbital fissure

If CN6 affected: Esotropia

final

Facial(Both sensory and motor)

Supplies: Muscles of facial expression, anterior 2/3rds tongue
F: Muscles of facial expression, taste, sensation of touch, pain, temperature *Helps with corneal reflex
Fo: Internal auditory meatus

very

Vesitibulocochlear(sensory)

Supplies: Vestibulobranch(Some fibers reach cerebellum though inf cerebellar peduncle) ; cochlear branch
Involved with: Lateral and medial vestibulospinal tracts
F: posture, static and dynamic balance *mostly sensory
FO: IAM

good

Glossopharyngeal(both sensory and motor)

Supplies:
F: lift pharyn and larynx, taste posterior tongue, blood pressure
FO: Jugualr foramen

vacations

Vagus(both sensory and motor)

Supplies: Pharynx, larynx, thoracic and abdominal viscera, epiglottis, aortic arch
F: Main parasympathetic nerve; supplies 75% of organs
Fo: Jugular foramen

are

Accessory(motor)

Supplies: SCM, trapezius, pharynx , soft palate mm
F: Flexion of neck, contralateral head rot, elevates and retracts scap
FO: Jug foramen

Heavenly

Hypoglossal(motor)

Supplies: Extrinsic and intrisic muscles of the tongue
F: Swallow, speak, move stuff in mouth
FO: Hypoglossal canal

Basal ganglia

Most important blood supply of the basal ganglia: Lenticulostriate arteries(small vessels off the MCA)

4 channels

Motor channel

Direct path

Structures involved

Striatum, GPI, SNR, thalamus

Striatum releases GABA to inhibit GPI and SNR, so no GABA is released to the thalamus , movement is stimulated

Cortex

Striatum(GABA inside)

GABA

GPI and SNR

GPI and SNR

NO GABA

Thalamus

Glutamate

To stimulate motor cortex

Indirect pathway

Structures involved

Striatum, GPE, Subthalamus nucleus, GPI, SNR, thalamus

Subthalamus nucleus releases glutamate which stimulates GPI and SNR, these release GABA to the thalamus and movement is inhibited

Cortex

Striatum

GPE

GABA

Subthalamic nucleus

Glutamate

GPI and SNR

GABA

Thalamus

thalamus inhibited

Breaks movement

Oculomotor channel

Conttrols eye movement, saccadic eye movement

Prefrontal channel

Cognitive processes of frontal lobe and behavior control

Limbic channel

Regulation of emotions

Cerebellum

Anatomy

connection with brainstem by cerebella peduncles

Superior cerebellar peduncle: Connects with midbrain

Middle cerebellar peduncle: Connects with pons

Inferior cerebellar peduncle: Connects with medulla

External feuatures

Two cerebellar hemispheres right and left

control extremities

Median vermis

Controls trunk

Peduncles

Extremities and trunk

Anterior lobe

regulation of muscle tone, coordination of skilled voluntary movement

Posterior lobe

Planning of voluntary activity

Flocculo nodular lobe

Maintenance of balance, control of eye movements

Inner white matter: Arbor vitae

Cells

Purkinje cells

Largest in brain essential to output tracts

Granule cells

Smaller ; use glutamate as MT and are excitatory

Nuclei

Dentate nucleus

Fine control of voluntary mvoements

Emboliform nucleus

Regulates precision of limb movements

Fastigal

Estimate movement of the body through space

Glubose

Balance, posture, and orientation

Input tracts

Cuneocerebellar tracts (Carry info from upper limbs and upper trunk)

Dorsal spinocerebellar tract (Carry info from lower limb and lower trunk)

Output tracts

Rostral spinocerebellar: Pain and temp from the upper extremities

Ventral spinocerebellar: Pain and temp coming from the lower extremities

Blood supply

PICA, AICA, SCA

Communication

Ascending(sensory) tracts

DCML

Function: Sensory info of fine touch,vibration and proprioception to post central gyrus

2 fibers

FG: T6 and below

FC: T6 and up

Originates in dorsal horn of SC
Terminates in post central gyrus

Decussation: At medulla

1st order: From effector to medulla

2nd Order: Medulla to VPL in thalamus

3rd order: VPL to post central gyrus

ALS Spinothalamic

F: Pain, temperature, crude touch

Decussation: Spinal cord

Descending (motor) tracts

Lateral corticospinal

Voluntary movement for the whole body

Starts in cortex and decussates in medulla

Supplies entire cord

Anterior Corticospinal

Voluntary movement for the upper extremity and trunk

Starts in cortex and bifurcates in the spinal cord

Ends at T10

Lateral vestibulospinal

Balance

Starts in the pons and supplies entire cord

Medial vestibuospinal

Controls head and neck

Originates at medulla and bifurcates at medulla
Ends at T1

Reticulospinal

2 tracts

Medullary

Pontine

Starts in superior colliculus in mid brain
Supplies the entire cord

Posture and gait

Tectospinal

Head and eye coordination

Starts in superior colliculus in mid brain
Ends at T1

Decussates: midbrain

Rubrospinal

Fine coordination

Starts in red nucleus in midbrain
ends T1

Decussates at midbrain

Neuron

Synapse

Electrical

Only in the CNS, gap junctions

Chemical

Most common, USe of neurotransmitters

Spine

Regions

Cervical

Vertebrae

7 total

C3-C7 considered typical

Distinguishing features: Foramina in transverse processes in which vertebral arteries go through and bifid spinous process

Atlas(C1)

Nodding head yes

Axis(C2)

Dens process

Shaking head no

Craniocervical ligaments (C1 and C2)

Alar ligament: secondary stabilization for transverse ligament

Apical Ligament

Transverse ligaments: Supports posterior dens and prevents anterior translation of of atlas on axis

Cruciate ligament:

Superior longitudinal band

Transverse lig

Inferior longitudinal band

Nerves

8 nerves

Joints

Facet

45 degrees

antlantooccipital

Atlantoaxial

Thoracic

Vertebrae

12 total

Unique

Demifacets on transverse process: two on each side

Facet orientation

60 degrees

Ligaments running the entire length of vertebral column

Posterior longitudinal ligamnent

Anterior longitudinal ligament

Supraspinous ligament

Other ligaments

Superior and inferior costotransverse ligaments

Rib attachment sites

Head of rib

Demifacet of vertebral body

Tubercle of rib

Demifacet of transverse process

Lumbar

Vertebrae

5

Facet orientation

90 degrees

Sacral

Vertebrae

5

Coccygeal

Vertebrae

3-5

Functions

Weight bearing

Protection of CNS and Viscera

Force attenuation

Allows and guides movement

Sites for muscular attachment

Provides upright posture

Muscles

Extrinsic

Extrinsic superficial

Trapezius

Lats

Rhomboid major

Rhomboid minor

levator scapulae

Intermediate extrinsic

Serratus posterior superior

Serratus posterior inferior

Function for both: Respiration and proprioception

Intrinsic

Superficial

Splenius capitus

Splenius cervicus

attach to transverse process

Erector spinae

Iliocostalis

Longissimus

Spinalis

Transversospinalis

Semispinalis

Multifidus

Rotatores

Deep segmental

Interspinalis

Levator costarum

Intertransversarii