01 lecture dpt 4 introduction and organization of the nervois system by abdul ghafoor sajjad

Abdul Ghafoor Sajjad Assistant Professor Riphah Collage of

Rehabilitation Sciences

DPTANATOMY IV

NEURO ANATOMY CREDIT HOURS 3(2-1)

Dr Abdul Ghafoor SajjadAssistant Professor

RCRS,RIU

DETAILED COURSE OUTLINE

• Central Nervous System: Disposition, Parts and Functions

• Brain stem (Pons, Medulla, and Mid Brain)

• Cerebrum • Cerebellum • Thalamus • Hypothalamus




• Internal Capsule • Blood Supply of Brain • Stroke and its types • Ventricles of Brain • CSF circulation and Hydrocephalus • Meninges of Brain




• Neural pathways (Neural Tracts) • Pyramidal and Extra pyramidal System

(Ascending and Descending tracts) • Functional significance of Spinal cord level • Cranial Nerves with special emphasis

upon IV, V, VII, XI, XII (their course, distribution, and palsies).

• Autonomic nervous system, its components

• Nerve receptors




• SPINAL CORD • Gross appearance • Structure of spinal cord • Grey and white matter (brief

description) • Meninges of spinal cord • Blood supply of spinal cord • Autonomic Nervous system



Recommended Text Books:

• Gray’s Anatomy by Prof. Susan Standring 39th Ed., Elsevier.

• CLINICAL NEUROANATOMY BY RICHARD S.SNELL 7TH EDITION.

• Clinically Oriented Anatomy by Keith Moore.

• Clinical Anatomy by R.J. Last, Latest Ed.



Lecture No 01

INTRODUCTION AND ORGANIZATION OF THE NERVOUS

SYSTEM

LECTURE OBJECTIVES

• To understand the basic organization of the main structure that form the nervous system.

• To gain the Three-dimensional appreciation of the parts of the brain and their relative position to one. another



NERVOUS SYSTEM

• A regulatory system of the body that consists of neurons and neuroglial cells.

OR • The body’s primary communication

and control system.• Can be divided according to:– Structural categories– Functional categories.



Nervous SystemStructural Organization

Structural subdivisions of the nervous system:

• Central nervous system (CNS)– Brain and Spinal cord

• Peripheral nervous system (PNS)– Cranial nerves (nerves that extend from

the brain)– Spinal nerves (nerves that extend from

the spinal cord)– ganglia (clusters of neuron cell bodies

(somas) located outside the CNS)



Nervous SystemFunctional Organization

Functional divisions of the nervous system:

• Sensory afferent division:– receives sensory information (input) from

receptors – transmits this information to the CNS.

• Motor efferent division:– transmits motor impulses (output) from

the CNS– to muscles or glands (effector organs).



Central Nervous System

BRAIN



Brain• An adult brain weighs between 1.35

and 1.4 kilograms (kg) (around 3 pounds) and has a volume of about 1200 cubic centimeters (cc).

• Brain size is not directly correlated with intelligence

• It is not the physical size of the brain that determines intelligence—it is the number of active synapses.



Support and Protection of the Brain

• The brain is protected and isolated by multiple structures:1. Bony cranium 2. Meninges:• Protective connective tissue membranes• Surround and partition portions of the brain.

3. Cerebrospinal fluid (CSF)• acts as a cushioning fluid.

4. Blood-brain barrier:• prevents entry of harmful materials from the

bloodstream. Abdul Ghafoor Sajjad Assistant

Professor Riphah Collage of Rehabilitation Sciences

Organization of Brain Tissue

• Gray matter:–Motor neuron and interneuron cell

bodies, dendrites, axon terminals– Unmyelinated axons.

• White matter:White matter:– composed primarily of Myelinated composed primarily of Myelinated

axons. axons.



A COMMON BRAIN DIVISION



FOREBRAIN

• Telencephalon: Cerebral Cortex, Basal Ganglia.

• Diencephalon: Thalamus, Hypothalamus.



Cerebral Cortex• The word "cortex" comes from the

Latin word for "bark" (of a tree). • The thickness of the cerebral cortex varies from 2 to 6 mm. • The right and left sides of the

cerebral cortex are connected by a thick band of nerve fibers called the "corpus callosum.“

• bulge on the cortex is called gyrus and a groove is called a sulcus.Abdul Ghafoor Sajjad Assistant

Professor Riphah Collage of Rehabilitation Sciences

Basal Ganglia(Part Of Telencaphalon Of Forebrain)

Functions:• Movement• The basal ganglia are a group of

structures, including the Globus Pallidus, Caudate Nucleus, Subthalamic Nucleus, Putamen And Substantia Nigra, that are important in coordinating movement.



Thalamus(Part Of Diencephalon Of Forebrain)

Functions:• Sensory processing• The thalamus receives sensory

information and relays this information to the cerebral cortex.

• The cerebral cortex also sends information to the thalamus which then transmits this information to other areas of the brain and spinal cord.



Hypothalamus(Part Of Diencephalon Of Forebrain)

Functions:• Body Temperature (acts as a

"thermostat")• Emotions• Hunger• Thirst• Circadian Rhythms



MIDBRAIN

Mesencephalon: tectum (inferior and superior colliculi) and tegmentum

BASIC FUNCTIONS:• Vision• Hearing• Eye movement• Motor control



HINDBRAIN

1. Metencephalon: Pons and Cerebellum

2. Metencephalon: MedullaBASIC FUNCTIONS:• Monitoring And Controlling Body

Movements• Homeostasis



The Pons

The pons are situated on the anterior surface of the cerebellum, inferior to the mid brain and superior to the medulla oblongata.



The Medulla Oblongata

• The medulla is the most inferior part of the brain stem. The cell bodies of several cranial nerves are found there.



Cerebellum

• The word "cerebellum" comes from the Latin word for "little brain." The cerebellum is located behind the brain stem. In some ways, the cerebellum is similar to the cerebral cortex: the cerebellum is divided into hemispheres and has a cortex that surrounds these hemispheres.



Cerebellum

Functions:• Movement• Balance• Posture



Brain stem

• The brain stem is a general term for the area of the brain between the thalamus and spinal cord. Structures within the brain stem include the Medulla, Pons, Tectum, Reticular Formation And Tegmentum. Some of these areas are responsible for the most basic functions of life such as breathing, heart rate and blood pressure.



CLINICAL NOTES

• Head injuries– Fracture of skull• Pond Fracture

– Brain Injuries• Contrecoup injuries• TBI (Explosion or Blast)



CLINICAL NOTES

– Intracranial Hemorrhage1. Epidural (anterior division of middle meningeal

artery)2. Subdural ( superior cerebral veins)3. Subarachnoid ( non traumatic leakage or

rupture of congenital aneurysm on circle of willis)

4. Cerebral {most common in HTN pt. due to rupture of lenticulostraite artery ( branch of Middle Cerebral Artery), involve descending nerve fiber in the internal capsule, produce hemiplegia of opposite side of the body}



CLINICAL NOTES

• Shaken baby syndrome• Space occupying lesions{ SOL

(tumor, hematoma, and abscess)}• Diagnosis – CT–MRI– PET



01 lecture dpt 4 introduction and organization of the nervois system by abdul ghafoor sajjad

Health & Medicine

brain size

brain spinal nerves

control system

regulatory system

adult brain

bloodbrain barrier

pyramidal system ascending

functions brain stem