Introduction to neurology for medical students brain, spinal cord, Olfactory, Optic , Oculomotor , Trochlear • 5 Trigeminal , 6 Abducent , Facial , Vestibulocochlear , Glossopharyngeal , Vagus, Accessory , Hypoglossal, cranial nerves, CEREBELLUM, MEDULLA OBLONGATA, SPINAL CORD, CAUDA EQUINA, THE MOTOR SYSTEM, UPPER MOTOR NEURON, pyramidal system, LOWER MOTOR NEURON, EXTRA PYRAMIDAL SYSTEM,BASAL GANGLIA

1. Introduction to
NEUROLOGY
Dr. WALID REDA ASHOUR
ASSISST. PROFESSOR OF
NEUROLOGY

3. INTRODUCTION

4. WHAT IS NEUROLOGY?
Neurology is the branch of medicine that
deals with diseases of the nervous system.

5. MAJOR DIVISIONS
NERVOUS
SYSTEM
CENTRAL
NERVOUS
SYSTEM
PERIPHERAL
NERVOUS
SYSTEM

6. CENTRAL NERVOUS SYSTEM

7. 1. Cerebrum
2. Brain stem
3. Cerebellum
CNS
Intracranial
part
Spinal
part
1- Spinal cord
2- Cauda equina

8. I- INTRACRANIAL PART

9. 1- CEREBRUM
Two (2) cerebral hemispheres.
Connected to:
1. Each other by CORPUS CALLOSUM.
2. Brain stem by CEREBRAL PEDUNCLES.
- Outer gray matter (cerebral cortex) contains certain
areas with specific functions.
- Inner white matter composed of nerve fibers
conducting impulses TO & FROM cerebral cortex

10. EACH cerebral hemisphere divided into :
FOUR ( 4 ) LOBES:
1. Frontal
2. Parietal
3. Temporal
4. Occipital

11. 2- Brain stem
Formed of :
1- Midbrain
2- Pons
3- Medulla
Connected to:
1. Cerebral hemisphere
by cerebral peduncles
2. Cerbellum by cerebellar
peduncles

12. BRAIN STEM contains motor nuclei of cranial
nerves:
• 3 & 4 in MIDBRAIN
• 5, 6 &7 in PONS
• 9, 10, 11 & 12 in MEDULLA
N.B. 1, 2 & 8
are sensory nerves have no
motor nuclei

13. NAMES OF CRANIAL NERVES
• 1 Olfactory
• 2 Optic
• 3 Oculomotor
• 4 Trochlear
• 5 Trigeminal
• 6 Abducent
• 7 Facial
• 8 Vestibulocochlear
• 9 Glossopharyngeal
• 10 Vagus
• 11 Accessory
• 12 Hypoglossal

14. CLASSIFICATION OF CRANIAL NERVES
• SENSORY : contain only sensory fibers
1- Olfactory
2- Optic
8- Vestibulocochlear
• MOTOR : contain only motor fibers
3- Oculomotor
4- Trochlear
6- Abducent
11- Accessory
12- Hypoglossal
• MIXED : contain both sensory and motor fibers
5- Trigeminal
7- Facial
9- Glossopharyngeal
10- Vagus

15. Sensory cranial nerves
N. Name Function Assessment
1 Olfactory Smell Examination of
smell
2 Optic Vision Acuity, field &
fundus
8 Vestibular
part
Equilibrium Caloric and
rotational chair
Cochlear
part
Hearing Watch test,
Weber test

16. Motor cranial nerves
N. Name Function Assessment
3 Oculomotor Motor to superior, inferior and
medial recti; inferior oblique
& levator palpebrae superioris
Ptosis, pupil, eye
movements &
squint
Parasympathetic to sphincter
papillae and ciliary muscle
4 Trochlear Motor to superior oblique Look to opposite
shoulder
6 Abducent Motor to lateral rectus Lateral eye
movement
11 Accessory Motor to sternocleidomastoid
and trapezius
Elevaton of
shoulders and
neck rotation
12 Hypoglossal Motor to muscles of tongue Tongue
movements

17. Mixed cranial nerves
N. Name Function Assessment
5 Trigeminal Muscles of
mastication &
sensations of face
Face sensations &
power of muscles of
mastication
7 Facial Muscles of facial
expression & taste
sensation in ant. 1/3
of tongue
Muscles of facial
expression & taste
sensation in ant. 1/3 of
tongue
10 Vagus Sensation and
movements of
Larynx, pharynx,
thoracic and
abdominal organs
Palatal and pharyngeal
reflexes & movements of
uvula
9 Glossopharyngeal Taste in post 2/3 of
tongue & gen.
sensation
Taste & general
sensation and
pharyngeal reflex

18. 3- CEREBELLUM
• Behind the brain stem
• Formed of : * Medline vermis
* Two cerebellar
hemispheres
• Composed of :
Outer grey matter and inner
white matter

19. MB
Pons C
MO
n Superior peduncle connects cerebellum with MIDBRAIN.
n Middle peduncle connects cerebellum with PONS.
n Inferior peduncle connects cerebellum with MEDULLA
OBLONGATA
CEREBELLAR PEDUNCLES

20. Left
Hemisphere
right
hemisphere
CEREBELLAR HEMISPHERES AND VERMIS
Cerebellar Hemispheres are the two bilateral structures.
Vermis is the unpaired midline structure between
the two hemispheres.
VERMIS

21. II- SPINAL PART

22. 1- SPINAL CORD
• Inside spinal canal
• End at lower border of L1 vertebra.
• Its lowermost 3 segments S3,4,5 = Conus.
• The above 4 segments L4,5 & S1,2 = Epiconus.
• Inner grey matter (cells) surrounded by
white matter.

23. SPINAL CORD

24. SPINAL CORD TRACTS
• White matter contains ascending and
descending nerve fibers (TRACTS):
1- ASCENDING
• Lateral & Ventral spinothalamic.
• Gracile & Cuneate.
• Spinocerebellar.
• Lissauer’s.
2- DESCENDING
• Corticospinal (pyramidal).
• Reticulospinal, vestibulospinal, tectospinal, rubrospinal &
olivospinal

25. 2- CAUDA EQUINA
• Collection of LUMBOSACRAL ROOTS which
fills the lower part of the spinal canal below
L1 vertebra.

26. THE MOTOR SYSTEM

27. Motor pathway

28. UPPER MOTOR NEURON
(pyramidal system)
* Originates in motor area 4 & premotor area 6
* Terminates at the anterior horn cells (AHCs)
of the different levels of the spinal cord.
* It supplies the opposite side of the body.

29. LOWER MOTOR NEURON
• Formed of AHCs & Peripheral motor nerves
(which transmit the motor impulses to the
voluntry muscles).

30. EXTRA PYRAMIDAL SYSTEM
• Originates from centers at various levels of CNS
mainly the BASAL GANGLIA.
• It controls the opposite side of the body.
CEREBELLAR SYSTEM
• Composed of Neo, Archi & Paleo- cerebellum.
• It co-ordinates the movements of the same side of
the body.

31. UMNL LMNL
Tone Increased, with
‘clasp knife’ quality
Decreased
Clonus Present Absent
Fasciculations Absent Present
Muscle Wasting Absent, but disuse
atrophy eventually
results
Present (within 2-3
weeks)
Tendon Reflexes Increased. Extensor
plantar reflexes.
Decreased or
absent. Flexor
plantar reflexes.
Distribution Whole limbs, with
more weakness in
the upper limb
extensors and lower
limb flexors
Specific muscle
groups affected (e.g.
in the distribution of
a spinal segment, or
just the proximal
muscles, etc.)

33. Thank you