Basic Neuro Anatomy

Chap1. Brain & Body

Ph.D. Jury Ham

Nerves system

1. CNS

Brain

Spinal cord

2. PNS

Somatic Nerve

Autonomic Nerve

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A few definitions

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A few Definitions

Locations in the Brain

Described relative to neuraxis

- an imaginary line drawn through the spinal cord

up to the front of the brain

The front end is anterior

The back end is posterior

The terms rostral (toward the head) and caudal (

toward the tail) are also used when referring to pa

rts of the brain

Dorsal (back) refers to the top of the head and the back The ventral (front) surface faces the ground. These directions are somewhat more complicated in humans because our neuraxis bends, so that the top of the head is now perpendicular to the back.

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A few Definitions

Locations in the Brain

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The Neuraxis

Anterior Posterior

Dorsal

Ventral

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The Neuraxis

Anterior

Posterial

Dorsal Ventral

superior

inferior

Lateral means to the side (away from the neuraxis) Medial (or mesial) means toward the middle (towards the neuraxis) Proximal: Areas of the brain that are near to one another Distal: Areas that are far from one another

201403 Ph.D. Jury HAM

A few Definitions

Locations in the Brain

201403 Ph.D. Jury HAM

A few Definitions

Locations in the Brain

Ipsilateral refers to structures on the same

side of the body

E.g. the olfactory bulbs send ipsilateral connections to the brain - the right bulb connects to the right hemisphere, and the left bulb connects to the left hemisphere

Contralateral refers to structures on opposite sides of the body

E.g. the left motor strip connects to the right side of the body

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A few Definitions

Slices of the Brain

fornix

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Division of nervous system

CNS

Central Nervous System

Brain

Spinal cord

PNS

Peripheral Nervous System

Cranial nerves

Spinal nerves

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Brain

Spinal cord Spinal

nerves

Cranial nerves

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Division of nervous system

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Sensory division Sensory

receptors

Motor division

Skeletal

muscle

Brain

Spinal

cord Spinal

nerves

Cranial

nerves

Central Nervous System

(brain and spinal cord)

Peripheral Nervous System

(cranial and spinal nerves)

Smooth m.

Cardiac m.

Glands

Autonomic

Nervous

System

Somatic

Nervous

System

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Division of nervous system

Grey matter

White matter

CNS

PNS

Nuclei Tracts

Ganglia Nerve

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Division of nervous system

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Receptor

Sensory or afferent neuron

Motor or efferent neuron Central

Nervous System

Effector (muscle or gland)

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Classification of Neurons Functional difference

Central nervous system Peripheral nervous system

Cell body

Interneurons

Dendrites

Axon

Axon

Sensory (afferent) neuron

Motor (efferent) neuron

Cell body

Axon (central process)

Axon (peripheral process)

Sensory receptor

Effector (muscle or gland)

Axon terminal

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Spinal cord

Extends downward through vertebral canal Begins at the foramen magnum and terminates at the first and second lumbar vertebrae (L1/L2) interspace

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Brainstem

Spinal cord

Foramen magnum

Cervical enlargement

Vertebral canal

Lumbar enlargement Conus medullaris

Cauda equina

Filum terminale

Conus medullaris

Lumbar enlargement

Cervical enlargement

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Spinal Nerves

ALL are mixed nerves

(except the first pair)

31 pairs of spinal nerves:

8 cervical nerves

(C1 to C8)

12 thoracic nerves

(T1 to T12)

5 lumbar nerves

(L1 to L5)

5 sacral nerves

(S1 to S5)

1 coccygeal nerve

(Co or Cc)

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Cauda equina

C1 C2 C3 C4 C5 C6 C7 C8 T1

T2

T3

T4

T5

T6

T7

T8

T9

T10

T11

T12

L1

L2

L3

L4

L5

S2 S3

S4

S1

S5 Co

Posterior view

Cervical nerves

Thoracic nerves

Lumbar nerves

Sacral nerves Coccygeal nerve

Notes!! Cervical spinal nerves exit from above the respective vertebra.. Spinal nerve R1 from above C1 Spinal nerve R2 from between C1&C2

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Spinal Nerves continued

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Autonomic Neurotransmitters

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Brain

Postganglionic fiber (axon)

Preganglionic fiber (axon)

Ganglion

Sympathetic neurons

ACh = acetylcholine (cholinergic)

NE = norepinephrine (adrenergic)

ACh

ACh

ACh

ACh

ACh ACh

NE

NE

Cranial parasympathetic neurons

Sacral parasympathetic neurons

Collateral ganglion

Paravertebral ganglion

Visceral effectors

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Sympathetic Division

Ph.D. Jury HAM

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Lacrimal gland

Skin

Eye

Blood vessels

Heart

Lungs

Adrenal gland Kidney

Uterus Penis

Liver

Stomach Gallbladder

Pancreas

Ovary

Scrotum

Small intestine

Large intestine

Trachea

Parotid gland, submandibular and sublingual glands

Urinary bladder

Preganglionic neuron

Postganglionic neuron

Sympathetic chain ganglia

Inferior mesenteric ganglion

Spinal cord

Superior mesenteric ganglion

Celiac ganglion

Fibers to skin, blood vessels, and adipose tissue

Celiac and pulmonary plexuses

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Parasympathetic Division

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Heart

Trachea

Lung

Gallbladder Liver

Stomach

Spleen

Pancreas

Small intestine

Large intestine

Kidney

Uterus Scrotum

Otic ganglion

Ciliary ganglion Eye

Penis Ovary

Sphenopalatine ganglion

Cranial nerve III

Cranial nerve VII

Submandibular ganglion

Cranial nerve IX

Cranial nerve X (Vagus)

Cardiac and pulmonary plexuses

Celiac plexus

Superior hypogastric plexus

Inferior hypogastric plexus

Spinal cord

Pelvic nerves

Urinary bladder

Parotid gland

Submandibular and sublingual glands

Lacrimal gland

Preganglionic neuron

Postganglionic neuron

Ph.D. Jury HAM

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Dermatom

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Ph.D. Jury HAM

C2 C3

C4

C5

C6

T1

C6

C7

S2

S3

C8

L1

L2

L3

L4

L5

T12

T1

S1

S5 C0

S4 S3

S2 S1

L5

L4

L3

L2

L1

L5

L1

C8 T1

T12

C7 C6

C5 C4

C3

C2

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Cranial Nerve

Ph.D. Jury HAM

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Cranial Nerve

Ph.D. Jury HAM

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Cranial Nerve

Ph.D. Jury HAM

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Cranial Nerve

Ph.D. Jury HAM

CN I Olfactory Olfactory

epithelium

Smell

CN II Optic Retina Vision

CN III Occulomotor Midbrain Eye movement;

accommodation

CN IV Trochlear Midbrain Eye movement

(superior oblique)

CN V Trigeminal Pons Sensation to face;

chewing

CN VI Abducens Pons Eye movement

( lateral rectus)

CN VII Facial Pons Facial expression;

taste to anterior

2/3 of tongue

CN VIII Vestibulocochlear Pons Hearing &

balance

CN IX Glossopharyngeal Medulla Salivation;

swallowing; taste

to posterior 1/3

of tongue

CN X Vagus Medulla Digestion; taste

to pharynx

CN XI Accessory Medulla Movement of

trapezius & SCM

CN XII Hypoglossal Medulla Movement of

tongue

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Brain Protection

Ph.D. Jury HAM

Bone Meninges CSF Cerebrpspinal fluid

Blood Brain Barrier

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Spinal cord Protection

Ph.D. Jury HAM

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Cerebrospinal Fluid

Ph.D. Jury HAM

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Cerebrospinal Fluid

Ph.D. Jury HAM

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Cerebrospinal Fluid

Ph.D. Jury HAM

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QUIZ

Ph.D. Jury HAM

Does a bigger brain mean you are smarter?

The debate is still on.

It seems that the higher brain to body mass an animal has, the smarter it is.

Einstein's overall brain was a normal size, but the specific portion known for spatial intelligence was wider and

had a unique anatomy.

Ha! Ha!

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Brain/Body size relationship

Ph.D. Jury HAM

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Brain/Body size relationship

Ph.D. Jury HAM

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Evolution of the Brain

Ph.D. Jury HAM

Ph.D. Jury HAM