1. Overview of Control Systems
Clinical Sciences Applied to Nursing
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2. General Organization of the Nervous System
Begins as a hollow tube
First segments of the tube become the brain
(Porth 2009) LWW Slide used with permission

3. Nervous System Functions
Directs immediate responses to stimuli,
usually by coordinating the activities of other organ systems.
It does this via Neurones
and the chemical messages between Neurones

4. The human body is made up of trillions of cells
The human body is made up of trillions of cells. Cells of the nervous system, called nerve cells or neurons, are specialized to carry "messages" through an electrochemical process.
These messages are carried via Neurons and neurone to neurone. The brain has about 100 billion neurons.
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5. At the synapses messages are sent and received
Electrical conduction (Saltatory) sets up chemical (Synapses) between neurones that allows them to communicate with each other
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6. Complexity in Responsibilities/Organisation
Millions of neurons may lie beneath a single square centimetre of brain surface.
Each synapses with as many as 600 other neurons.
Many different parts of the brain may be involved in a single task.
The nervous system is divided into several distinct systems.
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7. Complexity of the Nervous system
Organisation to Achieve this
Nervous System Responsibilities
Two major divisions:
Central Nervous Systems.
Peripheral Nervous System.
Perception of external and internal conditions and the body's response to them
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(Porth 2012) LWW image used with permission

8. A typical Neuron
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(Fox 2010) McGraw Hill image used with permission
(Porth 2012) LWW image used with permission

9. Introduction to
The brain
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10. 29/01/2018
Fox McGraw Hill 2009

11. Cerebrum Cerebellum Motor, cognitive, hearing , language, Speech etc.
Thalamus, Hypothalamus
Pituitary/
Pineal gland etc
Brain stem
Basal Ganglia
Cerebellum
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Fox McGraw Hill 2009

12. Marieb 14.6

13. Protection of the brain
The Skull and Cerebral Spinal fluid
The bony cranium is loosely jointed during early infant life and thus must be protected.
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14. The Brain Covering MENINGES Dura mater Arachnoid mater Pia Mater
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15. Dura Mater
Two layers
Inner layer bends over to form a fold that separates the cerebral hemispheres
A second fold (tentorium) separates the cerebrum from the cerebellum

16. Dura Mater (cont.)
Between the layers of the dura, at the base of each fold, venous blood drains out of the brain in a sinus
Bridging veins carry blood from the brain across the inner layer of the dura mater to the sinus
The sinus also collects cerebrospinal fluid
(Porth 2012) LWW image used with permission

17. Arachnoid Lies just beneath the dura mater Waterproof
Cerebrospinal fluid (CSF) lies under the arachnoid to cushion the brain
Extensions of the arachnoid (villi) poke through the inner layer of the dura mater into the sinuses, to let CSF drain into the sinuses
(Porth 2012) LWW image used with permission

18. Pia Mater Lies right on the surface of the brain
Holds the cerebral arteries in place
(Porth 2012) LWW image used with permission

19. Cerebrospinal Fluid
Leaks out of capillaries inside the brain’s hollow ventricles
Composition controlled by the blood-brain barrier
Passes out an opening below the cerebellum
Circulates around the brain and spinal cord in the subarachnoid space
Passes through arachnoid villi into blood in the dural sinuses and is returned to the heart
(Porth 2012) LWW image used with permission

20. Nervous System Divisions
Anatomical division of Nervous system
Central Nervous System
(Brain, Spinal Cord)
Peripheral Nervous
(Nerve connections
organs/tissues )
the CNS and body
between
System
The nervous system can be anatomically divided into the Central Nervous System – the brain, spinal cord encased in the bones of the cranium and vertebral column.
The peripheral nervous system which allows nerve connections between the CNS and the organs and tissues of the body i.e. the nerve trunks, plexus and nerve fibres
Encased in the Cranium and vertebral column
allows nerve connections between the CNS and the organs and tissues of the body i.e. the nerve trunks, plexus and nerve fibres
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21. The Parts of the Nervous System
Central Nervous system
Brain an Spinal Cord
Peripheral Nervous system
Neurones that carry information to and from the central nervous system
Peripheral
Autonomic
Somatic
Parasympathetic
Enteric
Central
Organisation of the Nervous system
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22. Nervous System - Physiology
of the nervous system
Physiological division
Conscious Mechanisms
Voluntary and
Somatic
Involuntary Control
Mechanisms
Autonomic
Sympathetic and Parasympathetic
E.G Skeletal muscle and joint movement
Physiologically the nervous system can be divided into a somatic part i.e. that which deals with the voluntary and concious aspect e.g. skeletal muscle movement / joint movement and the autonomic nervous system which deals with the involuntary control mechanisms e.g. regulation of heartbeat, circulation and digestive functions.
There are two parts which need to be distinguished within the autonomic nervous system – the sympathetic and parasympathetic. In order to gain an understanding of these two parts it is necessary to examine the arrangement (anatomy) and the functioning (physiology) seperately.
E.G regualting HR, circualtion, digestive functions
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23. Comparison between Somatic and Autonomic Nervous System
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Marieb 14.2

24. Endocrine System
Hormonal : androgens for men and oestradiol and progesterone for females) and neural interactions that influence and control sexual behaviour are complex but research efforts have made great progress in unfolding a fascinating story
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25. Central and Peripheral communication .
The other main control system of body
Endocrine organs located throughout body
Actions: mediate function of all tissues
Control of Endocrine function is through feedback mechanisms

26. Endocrine Hormones Chemical messengers Secreted by endocrine gland
Specific to target
Activate cellular change

27. Testosterone – Oestrogen
Hormones
E.G.
Ocytocin
Thyroxin
Cortisol
Insulin
Testosterone – Oestrogen
Fox

28. References Fox SI 2009 Human Physiology McGraw-Hill: Boston.
Marieb EN 2005 Essentails of Human Anatomy and Physiology, Pearson Benjamin Cummings
Porth (2009/ 2012) Pathophysiology Lippincott Williams and Wilkins: Philadelphia
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