the nervous system

THE NERVOUS THE NERVOUS SYSTEMSYSTEM

PHYSIOLOGY AND PHYSIOLOGY AND ANATOMY OF BODY ANATOMY OF BODY

CONTROLING SYSTEMCONTROLING SYSTEMCreated by:Created by: Yasmeen Yasmeen

Hani ArafshaHani Arafsha

GOALS AND OBJECTIVESGOALS AND OBJECTIVES

NEURONS: The structural components of the nervous system…

Structure and mechanism of a neuron (nervous cell). Types of neurons.

Neuroanatomy and an introduction to the Nervous system.

Structural classification… Central nervous system.. Peripheral nervous system..

The Brain… The skull: home of the brain division of the brain. Brain structures. She brain – He brain. Differences in the total brain sizes. Brain fitness: your guide to good brain health.

How the nervous system interacts with other body systems.

Nervous system diseases.. Alzheimer’s disease. Parkinson’s disease. Huntington's disease.

References and Closure..

Select the objective to view…

NEURONSNEURONS::The structural components of the The structural components of the

nervous system…nervous system…

Objectives:Objectives: Structure and mechanism of a neuron Structure and mechanism of a neuron (nervous cell).(nervous cell). Types of neurons.Types of neurons.

NEURONS:NEURONS:The structural components of the The structural components of the

nervous system…nervous system…

Structure and Structure and mechanism of a mechanism of a neuron (nervous neuron (nervous

cell).cell).

Types of Types of neurons.neurons.

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Structure and mechanism of a Structure and mechanism of a neuron (nervous cell).neuron (nervous cell).

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. The human brain has about 100 billion neurons that carry out the nerve impulses through a process called action potential.

A real view showing a neuron (nerve cell) NextNext

Neurons are similar to other cells in the Neurons are similar to other cells in the body because: body because: 1. Neurons are surrounded by a cell 1. Neurons are surrounded by a cell membrane. membrane. 2. Neurons have a nucleus that contains 2. Neurons have a nucleus that contains genes. genes. 3. Neurons contain cytoplasm, mitochondria 3. Neurons contain cytoplasm, mitochondria and other and other "organelles". . 4. Neurons carry out basic cellular processes 4. Neurons carry out basic cellular processes such as protein synthesis and energy such as protein synthesis and energy production. production. However, neurons differ from other However, neurons differ from other cells in the body because: cells in the body because: 1. Neurons have specialized extensions called 1. Neurons have specialized extensions called dendrites and axons. Dendrites bring dendrites and axons. Dendrites bring information to the cell body and axons take information to the cell body and axons take information away from the cell body. information away from the cell body. 2. Neurons communicate with each other 2. Neurons communicate with each other through an electrochemical process. through an electrochemical process. 3. Neurons contain some specialized 3. Neurons contain some specialized structures (for example, synapses) and structures (for example, synapses) and chemicals (for example, neurotransmitters). chemicals (for example, neurotransmitters).

Structure and mechanism of a neuron (nervous cell).Structure and mechanism of a neuron (nervous cell).

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http://web.mit.edu/esgbio/www/cb/org/organelles.html


Neurons are the oldest and Neurons are the oldest and longest cells in the body! You have longest cells in the body! You have many of the same neurons for your many of the same neurons for your whole life. Although other cells die whole life. Although other cells die and are replaced, many neurons are and are replaced, many neurons are never replaced when they die. In never replaced when they die. In fact, you have fewer neurons when fact, you have fewer neurons when you are old compared to when you you are old compared to when you are young. On the other hand, data are young. On the other hand, data published in November 1998 show published in November 1998 show that in one area of the brain (the that in one area of the brain (the hippocampus), new neurons CAN hippocampus), new neurons CAN grow in adult humans. grow in adult humans.

Neurons can be quite large - in Neurons can be quite large - in some neurons, such as some neurons, such as corticospinalcorticospinal neurons (from motor neurons (from motor cortex to spinal cord) or primary cortex to spinal cord) or primary afferent neurons (neurons that afferent neurons (neurons that extend from the skin into the spinal extend from the skin into the spinal cord and up to the brain stem), can cord and up to the brain stem), can be several feet long! be several feet long!

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A single neuron consist of:A single neuron consist of: CELL BODYCELL BODY: is the metabolic center of the : is the metabolic center of the

neuron, contains the Nucleus and Mitochondrion.neuron, contains the Nucleus and Mitochondrion. DENDRITESDENDRITES: convey incoming messages to the : convey incoming messages to the

cell body.cell body. AXON HILLOCKAXON HILLOCK: a cone like region from where : a cone like region from where

an axon arises.an axon arises. AXONSAXONS: generates nerve impulses and topically : generates nerve impulses and topically

conduct them away from the cell body." A nerve is conduct them away from the cell body." A nerve is a group of axons”.a group of axons”.

Presynaptic terminals: Presynaptic terminals: The swollen, distal end The swollen, distal end of an axon; contains a neurotransmitter substance of an axon; contains a neurotransmitter substance within synaptic vesicles. Also called synaptic within synaptic vesicles. Also called synaptic ending or synaptic bouton.ending or synaptic bouton.


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AxonsAxons Take information away Take information away

from the cell body from the cell body Smooth Surface Smooth Surface Generally only 1 axon per Generally only 1 axon per

cell cell No ribosomes No ribosomes Can have myelin Can have myelin Branch further from the Branch further from the

cell bodycell body

DendritesDendrites Bring information to the Bring information to the

cell body cell body Rough Surface (dendritic Rough Surface (dendritic

spines) spines) Usually many dendrites Usually many dendrites

per cell per cell Have ribosomes Have ribosomes No No myelin insulation Branch near the cell bodyBranch near the cell body

There are several differences between axons and There are several differences between axons and dendrites:dendrites:


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http://faculty.washington.edu/chudler/glia.html

NucleusNucleus - contains genetic material - contains genetic material (chromosomes) including information for (chromosomes) including information for cell development and synthesis of proteins cell development and synthesis of proteins necessary for cell maintenance and necessary for cell maintenance and survival. Covered by a membrane. survival. Covered by a membrane.

NucleolusNucleolus - produces ribosomes - produces ribosomes necessary for translation of genetic necessary for translation of genetic information into proteins information into proteins

Nissl BodiesNissl Bodies - groups of ribosomes used - groups of ribosomes used for protein synthesis. for protein synthesis.

Endoplasmic reticulum (ER)Endoplasmic reticulum (ER) - system of - system of tubes for transport of materials within tubes for transport of materials within cytoplasm. Can have ribosomes (rough cytoplasm. Can have ribosomes (rough ER) or no ribosomes (smooth ER). With ER) or no ribosomes (smooth ER). With ribosomes, the ER is important for protein ribosomes, the ER is important for protein synthesis. synthesis.

Golgi ApparatusGolgi Apparatus - membrane-bound - membrane-bound structure important in packaging peptides structure important in packaging peptides and proteins (including neurotransmitters) and proteins (including neurotransmitters) into vesicles. into vesicles.

Microfilaments/Neurotubules Microfilaments/Neurotubules - system of - system of transport for materials within a neuron and transport for materials within a neuron and may be used for structural support. may be used for structural support.

MitochondriaMitochondria - produce energy to fuel - produce energy to fuel cellular activities. cellular activities.


What is inside of a neuron? A neuron has many What is inside of a neuron? A neuron has many of the same "organelles," such as mitochondria, of the same "organelles," such as mitochondria, cytoplasm and a nucleus, as other cells in the cytoplasm and a nucleus, as other cells in the body. body.

Components of a neuron

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Types of neurons.Types of neurons. Neurons come in many different shapes and Neurons come in many different shapes and sizes. Some of the smallest neurons have cell sizes. Some of the smallest neurons have cell bodies that are only 4 microns wide. Some of the bodies that are only 4 microns wide. Some of the biggest neurons have cell bodies that are 100 biggest neurons have cell bodies that are 100 microns wide. (Remember that 1 micron is equal to microns wide. (Remember that 1 micron is equal to

one thousandth of a millimeter!!).one thousandth of a millimeter!!).

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One way to classify neurons is by the number of One way to classify neurons is by the number of extensions that extend from the neuron's cell body extensions that extend from the neuron's cell body

(soma).(soma). Bipolar neuronsBipolar neurons have two have two

processes extending from processes extending from the cell body (examples: the cell body (examples: retinal cells, olfactory retinal cells, olfactory epithelium cells).epithelium cells).

Pseudounipolar cellsPseudounipolar cells (example: dorsal root (example: dorsal root ganglion cells). Actually, ganglion cells). Actually, these cells have 2 axons these cells have 2 axons rather than an axon and rather than an axon and dendrite. One axon extends dendrite. One axon extends centrally toward the spinal centrally toward the spinal cord, the other axon extends cord, the other axon extends toward the skin or muscle.toward the skin or muscle.

Multipolar neuronsMultipolar neurons have have many processes that many processes that extend from the cell body. extend from the cell body. However, each neuron has However, each neuron has only one axon (examples: only one axon (examples: spinal motor neurons, spinal motor neurons, pyramidal neurons, pyramidal neurons, Purkinje cells).Purkinje cells).

Types of neurons.Types of neurons.

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Neurons can also be classified by the direction Neurons can also be classified by the direction that they send information:that they send information:

Sensory (or afferent) neurons:Sensory (or afferent) neurons: send information from send information from sensory receptors (e.g., in skin, eyes, nose, tongue, sensory receptors (e.g., in skin, eyes, nose, tongue, ears) TOWARD the central nervous system. ears) TOWARD the central nervous system.

Motor (or efferent) neurons:Motor (or efferent) neurons: send information AWAY send information AWAY from the central nervous system to muscles or from the central nervous system to muscles or glands. glands.

Interneurons:Interneurons: send information between sensory send information between sensory neurons and motor neurons. Most interneurons are neurons and motor neurons. Most interneurons are

located in the central nervous system.located in the central nervous system.

Types of neurons.Types of neurons.

objectivesobjectives

Neuroanatomy and an Neuroanatomy and an introduction to the Nervous introduction to the Nervous

system.system.

IntroductionIntroduction

Neuroanatomy and an Neuroanatomy and an introduction to the Nervous introduction to the Nervous

system.system.

Neuroanatomy is the structure of the nervous Neuroanatomy is the structure of the nervous system. To learn how the nervous system functions, system. To learn how the nervous system functions, you must learn how the nervous system is put you must learn how the nervous system is put together.together.

the nervous system maintains body homeostasis the nervous system maintains body homeostasis with electrical signals; provides for sensation, higher with electrical signals; provides for sensation, higher mental functions, and emotional response; and mental functions, and emotional response; and activates muscles and glands.activates muscles and glands.

the nerves system is the master controlling and the nerves system is the master controlling and communicating system of the body. Every thought, communicating system of the body. Every thought, action and emotion reflects its activity. Its signaling action and emotion reflects its activity. Its signaling device, or means of communicating with body cells, device, or means of communicating with body cells, is electrical impulses, which are rapid and specific is electrical impulses, which are rapid and specific and cause almost immediate responses. and cause almost immediate responses.

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To carry out its normal role, the nervous system has To carry out its normal role, the nervous system has three over lapping functions:three over lapping functions:

1) Much like a 1) Much like a sentrysentry, it uses its millions of sensory , it uses its millions of sensory receptors to receptors to monitor changesmonitor changes occurring both inside and occurring both inside and outside the body. These changes are called outside the body. These changes are called stimulistimuli, , and the gathered information is called and the gathered information is called sensory inputsensory input..

2) It 2) It processesprocesses and and interpretsinterprets the sensory input and the sensory input and makes decisions about what should be done at each makes decisions about what should be done at each moment – a process called moment – a process called integrationintegration..

3) It then 3) It then effects a responseeffects a response by activating muscles or by activating muscles or glands (glands (effctorseffctors) via ) via motor outputmotor output..

Neuroanatomy and an introduction to the Nervous system.Neuroanatomy and an introduction to the Nervous system.


Structural classification Structural classification of the nervous systemof the nervous system

Objectives:Objectives: Central Nervous system (CNS)Central Nervous system (CNS) Peripheral Nervous system (PNS)Peripheral Nervous system (PNS)

Structural classification of the Structural classification of the nervous systemnervous system

First: The Central First: The Central Nervous System Nervous System

Second: The Second: The Peripheral Peripheral

Nervous SystemNervous System

The nervous system can be The nervous system can be divided into several connected divided into several connected systems that function together. Let's systems that function together. Let's take the simple division: take the simple division: The Nervous System is divided into:The Nervous System is divided into:

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The Central Nervous The Central Nervous SystemSystem

The central nervous system is The central nervous system is divided into two parts: the divided into two parts: the brainbrain and the and the spinal cordspinal cord. The average . The average adult human brain weighs 1.3 to adult human brain weighs 1.3 to 1.4 kg (approximately 3 pounds). 1.4 kg (approximately 3 pounds). The brain contains about 100 The brain contains about 100 billion billion nerve cells (neurons)nerve cells (neurons) and and trillions of "support cells" called trillions of "support cells" called gliaglia. The . The spinal cordspinal cord is about 43 is about 43 cm long in adult women and 45 cm long in adult women and 45 cm long in adult men and weighs cm long in adult men and weighs about 35-40 grams. The vertebral about 35-40 grams. The vertebral column, the collection of bones column, the collection of bones (back bone) that houses the (back bone) that houses the spinal cordspinal cord, is about 70 cm long. , is about 70 cm long. Therefore, the spinal cord is much Therefore, the spinal cord is much shorter than the vertebral columnshorter than the vertebral column . .

Structural classification of the nervous systemStructural classification of the nervous system

The Central Nervous System(Brain and Spinal

Cord) Click hereClick here

The Peripheral Nervous The Peripheral Nervous SystemSystem

The The peripheral nervous systemperipheral nervous system is divided into two major is divided into two major parts: parts: the somatic nervous systemthe somatic nervous system and and the autonomic nervous the autonomic nervous system.system.


2. Autonomic Nervous System2. Autonomic Nervous System The autonomic nervous system The autonomic nervous system is divided into three parts: the sympathetic nervous system, is divided into three parts: the sympathetic nervous system, the parasympathetic nervous system and the enteric nervous the parasympathetic nervous system and the enteric nervous system. The autonomic nervous system controls smooth system. The autonomic nervous system controls smooth muscle of the viscera (internal organs) and glands The muscle of the viscera (internal organs) and glands The preganglionic neuron is located in either the brain or the spinal preganglionic neuron is located in either the brain or the spinal cord. This preganglionic neuron projects to an autonomic cord. This preganglionic neuron projects to an autonomic ganglion. The postganglionic neuron then projects to the ganglion. The postganglionic neuron then projects to the target organ.. target organ.. Notice that the somatic nervous system has only one Notice that the somatic nervous system has only one neuron between the central nervous system and the target neuron between the central nervous system and the target organ while the autonomic nervous system uses two neurons. organ while the autonomic nervous system uses two neurons. The enteric nervous system is a third division of the The enteric nervous system is a third division of the autonomic nervous system that you do not hear much about. autonomic nervous system that you do not hear much about. The enteric nervous system is a meshwork of nerve fibers that The enteric nervous system is a meshwork of nerve fibers that innervate the viscera (gastrointestinal tract, pancreas, gall innervate the viscera (gastrointestinal tract, pancreas, gall bladder).bladder).

1. Somatic Nervous System1. Somatic Nervous System The somatic nervous system The somatic nervous system consists of peripheral nerve fibers that send sensory consists of peripheral nerve fibers that send sensory information to the central nervous system AND motor nerve information to the central nervous system AND motor nerve fibers that project to skeletal muscle. The picture on the left fibers that project to skeletal muscle. The picture on the left shows the somatic motor system. The cell body is located in shows the somatic motor system. The cell body is located in either the brain or spinal cord and projects directly to a either the brain or spinal cord and projects directly to a skeletal muscle. skeletal muscle.

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In the Peripheral Nervous System, In the Peripheral Nervous System, neurons can be functionally divided in neurons can be functionally divided in 3 ways: 3 ways:

1 Sensory (afferent) - carry information INTO the central nervous system from sense organs.

OR Motor (efferent) - carry information away from the central nervous system (for muscle control).

2 Cranial - connects the brain with the periphery.

OR

Spinal - connects the spinal cord with the periphery. 3 Somatic - connects the skin or muscle with the central nervous

system.

OR Visceral - connects the internal organs with the central nervous system.

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Some differences between the Some differences between the Peripheral Nervous System (PNS) and Peripheral Nervous System (PNS) and the Central Nervous System (CNS):the Central Nervous System (CNS):

In the CNS, collections of neurons are In the CNS, collections of neurons are called nuclei.called nuclei.In the PNS, collections of neurons are In the PNS, collections of neurons are called ganglia. called ganglia. In the CNS, collections of axons are In the CNS, collections of axons are called tracts.called tracts.In the PNS, collections of axons are called In the PNS, collections of axons are called nervesnerves


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The following table shows how the nervous system can be The following table shows how the nervous system can be divided. The bottom row of the table contains the names of divided. The bottom row of the table contains the names of specific areas within the brain. specific areas within the brain. Divisions of the Nervous Divisions of the Nervous System System



The Brain…The Brain…Objectives:Objectives:

The skull: home of the brainThe skull: home of the brain division of the brain.division of the brain. Brain structures.Brain structures. She brain – He brain.She brain – He brain.Brain fitness: your guide to good brain healthBrain fitness: your guide to good brain health..

The Brain…The Brain…

Although some people may Although some people may think that the brain is like a bowl of think that the brain is like a bowl of jell-O, the brain is NOT a bowl of jell-O, the brain is NOT a bowl of jell-O. Unlike a bowl of jell-O, the jell-O. Unlike a bowl of jell-O, the brain is not a uniform material. brain is not a uniform material. Rather, the brain is made up of Rather, the brain is made up of many different areas, each having many different areas, each having a particular structure and functiona particular structure and function..

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The skull:The skull: home of the brain home of the brain

Your brain is protected Your brain is protected by several bones. There are by several bones. There are eight bones that surround eight bones that surround your brain: one frontal your brain: one frontal bone; two parietal bones, bone; two parietal bones, two temporal bones, one two temporal bones, one occipital bone, one occipital bone, one sphenoid bone and one sphenoid bone and one ethmoid bone. These eight ethmoid bone. These eight bones make up the cranium. bones make up the cranium. Another 14 bones in the Another 14 bones in the face make up the entire face make up the entire skull. There are also 3 small skull. There are also 3 small bones in each ear. Also bones in each ear. Also protecting your brain are 3 protecting your brain are 3 layers of tissue called the layers of tissue called the meninges. A few of the meninges. A few of the bones have been colored in bones have been colored in the diagram to the right. the diagram to the right.

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There is a large opening, called the foramen There is a large opening, called the foramen magnum, located in the back of the occipital bone. This magnum, located in the back of the occipital bone. This is where the medulla ends and projects out of the skull. is where the medulla ends and projects out of the skull. Smaller holes in the skull, called foramina, allow Smaller holes in the skull, called foramina, allow nerves and blood vessels to enter and leave the nerves and blood vessels to enter and leave the cranium. The picture in the bottom shows the base of cranium. The picture in the bottom shows the base of the skull. The places in the skull where the bones the skull. The places in the skull where the bones come together are called sutures. These sutures are come together are called sutures. These sutures are flexible in young children, but become fixed as you flexible in young children, but become fixed as you age. age.

The skull: home of the brainThe skull: home of the brain

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Divisions of the Brain

Major Division Subdivision Structures

Telencephalon Neocortex; Basal Ganglia; Amygdala; Hippocampus; Lateral Ventricles Prosencephalon

(Forebrain)

Diencephalon Thalamus; Hypothalamus; Epithalamus; Third Ventricle

Mesencephalon (Midbrain) Mesencephalon Tectum; Tegmentum; Cerebral

Aqueduct

Metencephalon Cerebellum; Pons; Fourth Ventricle Rhombencephalon (Hindbrain)

Myelencephalon Medulla Oblongata; Fourth Ventricle

Divisions of the BrainDivisions of the Brain

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The subdivisions of the brainThe subdivisions of the brain

Telencephalon Diencephalon

Mesencephalon (Midbrain) Metencephalon

Myelencephalon

Division of the brainDivision of the brain

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Lobes of the brainLobes of the brain The average human brain weighs about 1,400 grams The average human brain weighs about 1,400 grams (3 lb). When the brain is removed from the skull, it looks (3 lb). When the brain is removed from the skull, it looks a bit like a large pinkish-gray walnut. The brain can be a bit like a large pinkish-gray walnut. The brain can be divided down the middle lengthwise into two halves divided down the middle lengthwise into two halves called the cerebral hemispheres. Each hemisphere of the called the cerebral hemispheres. Each hemisphere of the cerebral cortex is divided into four lobes by various sulci cerebral cortex is divided into four lobes by various sulci and gyri...the sulci (or fissures) are the grooves and the and gyri...the sulci (or fissures) are the grooves and the gyri are the "bumps" that can be seen on the surface of gyri are the "bumps" that can be seen on the surface of the brain. The folding of the cerebral cortex produced by the brain. The folding of the cerebral cortex produced by these bumps and grooves increases the amount of these bumps and grooves increases the amount of cerebral cortex that can fit in the skull. (In fact, the total cerebral cortex that can fit in the skull. (In fact, the total surface area of the cerebral cortex is about 324 square surface area of the cerebral cortex is about 324 square inches - about the size of a full page of newspaper!). inches - about the size of a full page of newspaper!). Although most people have the same patterns of gyri Although most people have the same patterns of gyri and sulci on the cerebral cortex, no two brains are and sulci on the cerebral cortex, no two brains are exactly alike.exactly alike.


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FRONTAL LOBEFRONTAL LOBE Located in front of the central Located in front of the central sulcus. sulcus. Concerned with reasoning, Concerned with reasoning, planning, parts of speech and planning, parts of speech and movement (motor cortex), movement (motor cortex), emotions, and problem-solving.emotions, and problem-solving.

PARIETAL LOBE PARIETAL LOBE Located behind the central Located behind the central sulcus. sulcus. Concerned with perception of Concerned with perception of stimuli related to touch, pressure, stimuli related to touch, pressure, temperature and pain. temperature and pain.

TEMPORAL LOBE TEMPORAL LOBE Located below the lateral Located below the lateral fissure. fissure. Concerned with perception and Concerned with perception and recognition of auditory stimuli recognition of auditory stimuli (hearing) and memory (hearing) and memory (hippocampus). (hippocampus).

OCCIPITAL LOBEOCCIPITAL LOBE Located at the back of the brain, Located at the back of the brain, behind the parietal lobe and behind the parietal lobe and temporal lobe. temporal lobe. Concerned with many aspects of Concerned with many aspects of vision. vision.


Lobes of the brainLobes of the brain

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A top view of the brainA top view of the brain

From a top view, notice how the brain is divided into two From a top view, notice how the brain is divided into two halves, called hemispheres. Each hemisphere communicates halves, called hemispheres. Each hemisphere communicates with the other through the corpus callosum, a bundle of nerve with the other through the corpus callosum, a bundle of nerve fibers. (Another smaller fiber bundle that connects the two fibers. (Another smaller fiber bundle that connects the two

hemispheres is called the anterior commissure).hemispheres is called the anterior commissure).

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Brain structuresBrain structuresClick on one of the question marks beside each Click on one of the question marks beside each structure to view its characteristics…structure to view its characteristics…

Brain stem

hypothalamushypothalamus

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Cerebral CortexCerebral Cortex

Functions:Functions: Thought Thought Voluntary Voluntary

movement movement Language Language Reasoning Reasoning Perception Perception

The word "cortex" comes from the Latin word for "bark" (of a tree). This is because the cortex is a sheet of tissue that makes up the outer layer of the brain. 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." In higher mammals such as humans, the cerebral cortex looks like it has many bumps and grooves. A bump or bulge on the cortex is called a gyrus (the plural of the word gyrus is "gyri") and a groove is called a sulcus (the plural of the word sulcus is "sulci"). Lower mammals, such as rats and mice, have very few gyri and sulci.

Brain structuresBrain structures

Return to structuresReturn to structures

CerebellumCerebellum

Functions:Functions: Movement Movement Balance Balance PosturePosture

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.



Brain stemBrain stem

Functions:Functions: Breathing Breathing Heart Rate Heart Rate Blood Blood

PressurePressure

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.



The hypothalamus is composed of several different areas and is located at the base of the brain. Although it is the size of only a pea (about 1/300 of the total brain weight), the hypothalamus is responsible for some very important functions. One important function of the hypothalamus is the control of body temperature. The hypothalamus acts as a "thermostat" by sensing changes in body temperature and then sending signals to adjust the temperature. For example, if you are too hot, the hypothalamus detects this and then sends a signal to expand the capillaries in your skin. This causes blood to be cooled faster. The hypothalamus also controls the pituitary.

HypothalamusHypothalamus

Functions:Functions: Body Body

Temperature Temperature Emotions Emotions Hunger Hunger Thirst Thirst Circadian Circadian

Rhythms Rhythms



ThalamusThalamus

Functions:Functions: Sensory Sensory

processinprocessing g

MovemenMovement t

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.



MidbrainMidbrain

Functions:Functions: Vision Vision Audition Audition Eye Eye

Movement Movement Body Body

MovementMovement

The midbrain includes structures such as the superior and inferior colliculi and red nucleus. There are several other areas also in the midbrain.



PonsPons

FunctionsFunctions:: Cardiovascular Cardiovascular

and respiratory and respiratory control center.control center. The pons are

continuous with the medulla



MedullaMedulla

FunctionsFunctions:: Heart rateHeart rate Breathing.Breathing. Blood pressure.Blood pressure. Swallowing and Swallowing and

vomitingvomiting



She brain – He brainShe brain – He brain Bigger - Stronger - Faster...are there really any Bigger - Stronger - Faster...are there really any differences between female brains and male brains? differences between female brains and male brains? Differences between the brains of men and women Differences between the brains of men and women have generated considerable scientific and public have generated considerable scientific and public interest. If there are differences in the way that men interest. If there are differences in the way that men and women behave, then it is reasonable to suppose and women behave, then it is reasonable to suppose that their brains have something to do these behavioral that their brains have something to do these behavioral differences. Just what are these differences and where differences. Just what are these differences and where in the brain might these differences be located? in the brain might these differences be located? For hundreds of years, scientists have searched for For hundreds of years, scientists have searched for differences between the brains of men and women. differences between the brains of men and women. Early research showing that male brains were larger Early research showing that male brains were larger than female brains was used to "prove" that male than female brains was used to "prove" that male brains were superior to female brains. Of course, this brains were superior to female brains. Of course, this "proof" is NOT so simple and straight forward as you "proof" is NOT so simple and straight forward as you will see. Nevertheless, even today, there is plenty of will see. Nevertheless, even today, there is plenty of controversy about the differences in the brains of men controversy about the differences in the brains of men and women. Not only from an anatomical point of view, and women. Not only from an anatomical point of view, but also from a functional point of view - in other but also from a functional point of view - in other words, just what do the differences in the brains words, just what do the differences in the brains mean? mean?

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Hormones that are present during a baby's Hormones that are present during a baby's development will affect the brain and determine development will affect the brain and determine whether the brain will be female or male. Studies that whether the brain will be female or male. Studies that have looked at differences in the brains of males and have looked at differences in the brains of males and females have focused on: females have focused on: Total Brain Size Total Brain Size The Corpus Callosum The Corpus Callosum The Hypothalamus The Hypothalamus

Women and Men - Boys and GirlsWomen and Men - Boys and GirlsThe behavioral and neurological differences between The behavioral and neurological differences between men and women require further study. Perhaps new men and women require further study. Perhaps new studies will find neuroanatomical differences that studies will find neuroanatomical differences that explain some of the complex differences between male explain some of the complex differences between male and female behavior. However, from a review of the and female behavior. However, from a review of the current scientific evidence, it appears that differences current scientific evidence, it appears that differences in many cognitive behaviors (for example, memory) are in many cognitive behaviors (for example, memory) are related more to individual differences between people related more to individual differences between people than to whether people are female or male. than to whether people are female or male.

She brain – He brainShe brain – He brain

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Brain fitness:Brain fitness: your guide to good brain your guide to good brain

healthhealth

1. Wear your seat belt!1. Wear your seat belt! In a car, truck or airplane, your In a car, truck or airplane, your seat belt will help protect your seat belt will help protect your head and brain from injury. Motor head and brain from injury. Motor vehicle accidents are by far the vehicle accidents are by far the greatest causes of brain injuries, greatest causes of brain injuries, accounting for 37-50% of all brain accounting for 37-50% of all brain injuries injuries

2. Wear your helmet!2. Wear your helmet! Whether you are biking, skating or Whether you are biking, skating or skateboarding, your helmet will skateboarding, your helmet will protect your head if you fall. Head protect your head if you fall. Head injury is the most common cause of injury is the most common cause of death in bicycle crashes accounting death in bicycle crashes accounting for 62% of all bicycle-related deaths. for 62% of all bicycle-related deaths.

33. Stay away from illegal drugs!. Stay away from illegal drugs! Drugs alter brain function, no Drugs alter brain function, no question about that. Although question about that. Although damage done by some drugs can damage done by some drugs can be reversed, some drugs may be reversed, some drugs may change brain function change brain function permanently. Why take the permanently. Why take the chance? chance?

4. Know the risks involved with 4. Know the risks involved with sports!sports! This applies mainly to boxing, This applies mainly to boxing, football and the martial arts. football and the martial arts. However, even soccer, climbing, However, even soccer, climbing, horseback riding, diving and skiing horseback riding, diving and skiing have risks. Always wear your safety have risks. Always wear your safety equipment properly and be in good equipment properly and be in good physical condition for your sport. physical condition for your sport.

You are born with just about all the neurons (nerve cells) that your You are born with just about all the neurons (nerve cells) that your brain will ever have. Damaged brains are NOT easy to fix. Here are brain will ever have. Damaged brains are NOT easy to fix. Here are some suggestions for good brain health.some suggestions for good brain health.

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5. Look before you leap!5. Look before you leap! I know it sounds impossible, but I know it sounds impossible, but people DO dive into swimming pools people DO dive into swimming pools without water. Dive only in the deep without water. Dive only in the deep end of the pool and make sure that the end of the pool and make sure that the water in the lake and at the beach is water in the lake and at the beach is deep enough to dive in head first. Also, deep enough to dive in head first. Also, be aware of any objects, such as large be aware of any objects, such as large rocks, that may be hidden under the rocks, that may be hidden under the water. water.

6. Look both ways before 6. Look both ways before crossing the street!crossing the street!

I know that you have heard this I know that you have heard this one before, but accidents do one before, but accidents do happen and you can't be happen and you can't be wearing your helmet all the wearing your helmet all the time. time.

7. Stay away from guns!7. Stay away from guns! I don't think I have to explain this I don't think I have to explain this

one.one.

8. Make sure you have a 8. Make sure you have a "good" surface around your "good" surface around your playground equipment! playground equipment! Just in case you fall off of a Just in case you fall off of a climber, a soft impact-absorbing climber, a soft impact-absorbing surface will cushion your drop. surface will cushion your drop.

Brain fitness: your guide to good brain healthBrain fitness: your guide to good brain health

10. Eat right!10. Eat right! Your brain needs energy to work its Your brain needs energy to work its best. best.

9. Dispose of chemicals properly!9. Dispose of chemicals properly! Many chemicals, such as pesticides Many chemicals, such as pesticides and cleaners, contain neurotoxins and cleaners, contain neurotoxins that can kill nerve cells and damage that can kill nerve cells and damage nerves. These dangerous chemicals nerves. These dangerous chemicals can be found in your home or at can be found in your home or at places of work. Dispose of these places of work. Dispose of these materials properly! materials properly!


How the nervous system interacts How the nervous system interacts with other body systems.with other body systems.

ObjectivesObjectives:: skeletal systemskeletal system cardiovascular systemcardiovascular system muscular systemmuscular system endocrine system endocrine system lymphatic systemlymphatic system respiratory systemrespiratory system digestive systemdigestive system reproductive systemreproductive system urinary systemurinary system

How the nervous system interacts with How the nervous system interacts with other body systems.other body systems.

All of the systems within the body All of the systems within the body interact with one another to keep an interact with one another to keep an organism healthy. Although each organism healthy. Although each system has specific functions, they system has specific functions, they are all interconnected and are all interconnected and dependent on one another. The dependent on one another. The nervous system controls various nervous system controls various organs of the body directly. The organs of the body directly. The brain also receives information from brain also receives information from many organs of the body and many organs of the body and adjusts signals to these organs to adjusts signals to these organs to maintain proper functioning. maintain proper functioning.

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The Skeletal systemThe Skeletal system

Function of the skeletal system..Function of the skeletal system.. The skeletal system makes up the framework of The skeletal system makes up the framework of the body and allows us to move when our muscles the body and allows us to move when our muscles contract. It stores minerals (e.g. calcium, contract. It stores minerals (e.g. calcium, phosphorous) and releases them into the body when phosphorous) and releases them into the body when they are needed. The skeletal system also protects they are needed. The skeletal system also protects internal organs and produces blood cells. internal organs and produces blood cells.

Interaction with the nervous system..Interaction with the nervous system.. Bones provide calcium that is essential for the proper Bones provide calcium that is essential for the proper

functioning of the nervous system. functioning of the nervous system. The skull protects the brain from injury. The skull protects the brain from injury. The vertebrae protect the spinal cord from injury. The vertebrae protect the spinal cord from injury. Sensory receptors in joints between bones send Sensory receptors in joints between bones send

signals about body position to the brain. signals about body position to the brain. The brain regulates the position of bones by controlling The brain regulates the position of bones by controlling

muscles. muscles.

How the nervous system interacts with other body systems.How the nervous system interacts with other body systems.

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The Cardio vascular systemThe Cardio vascular systemFunction of the cardiovascular Function of the cardiovascular

system…system… The cardiovascular system delivers The cardiovascular system delivers oxygen, hormones, nutrients and white oxygen, hormones, nutrients and white blood cells around the body by pumping blood cells around the body by pumping blood, and it removes waste products. blood, and it removes waste products.

Interaction with the nervous system…Interaction with the nervous system… Endothelial cells maintain the blood-brain barrier. Endothelial cells maintain the blood-brain barrier. Baroreceptors send information to the brain about Baroreceptors send information to the brain about

blood pressure. blood pressure. Cerebrospinal fluid drains into the venous blood Cerebrospinal fluid drains into the venous blood

supply. supply. The brain regulates heart rate and blood pressure. The brain regulates heart rate and blood pressure.


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The muscular systemThe muscular system

Function of the muscular system…Function of the muscular system… Different types of muscles enable motion, Different types of muscles enable motion, generate heat to maintain body temperature, generate heat to maintain body temperature, move food through digestive tract and move food through digestive tract and contract the heart. contract the heart.

Interaction with the nervous system…Interaction with the nervous system… Receptors in muscles provide the brain Receptors in muscles provide the brain

with information about body position and with information about body position and movement. movement.

The brain controls the contraction of The brain controls the contraction of skeletal muscle. skeletal muscle.

The nervous system regulates heart rate The nervous system regulates heart rate and the speed at which food moves and the speed at which food moves through the digestive tract. through the digestive tract.


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The Endocrine systemThe Endocrine systemFunction of the endocrine system…Function of the endocrine system… The endocrine system secretes The endocrine system secretes hormones into blood and other body hormones into blood and other body fluids. These chemicals are important fluids. These chemicals are important for metabolism, growth, water and for metabolism, growth, water and mineral balance, and the response to mineral balance, and the response to stress. stress.

Interaction with the nervous system…Interaction with the nervous system… Hormones provide feedback to the brain to affect Hormones provide feedback to the brain to affect

neural processing. neural processing. Reproductive hormones affect the development of Reproductive hormones affect the development of

the nervous system. the nervous system. The hypothalamus controls the pituitary gland and The hypothalamus controls the pituitary gland and

other endocrine glands. other endocrine glands.


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The Lymphatic systemThe Lymphatic systemFunction of the lymphatic Function of the lymphatic

system…system… The lymphatic system protects The lymphatic system protects the body from infection. the body from infection.

Interaction with the nervous Interaction with the nervous system…system…

The brain can stimulate defense The brain can stimulate defense mechanisms against infection mechanisms against infection


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The Respiratory SystemThe Respiratory System

Function of the respiratory system…Function of the respiratory system… The respiratory system supplies The respiratory system supplies oxygen to the blood and removes oxygen to the blood and removes carbon dioxide. carbon dioxide.

Interaction with the nervous system…Interaction with the nervous system…The brain monitors respiratory volume and The brain monitors respiratory volume and blood gas levels. blood gas levels. The brain regulates respiratory rate. The brain regulates respiratory rate.


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The Digestive systemThe Digestive systemFunction of the digestive system…Function of the digestive system…

The digestive system stores and digests The digestive system stores and digests foods, transfers nutrients to the body, foods, transfers nutrients to the body, eliminates waste and absorbs water. eliminates waste and absorbs water.

Interaction with the nervous system…Interaction with the nervous system… Digestive processes provide the building blocks for Digestive processes provide the building blocks for

some neurotransmitters. some neurotransmitters. The autonomic nervous system controls the tone of The autonomic nervous system controls the tone of

the digestive tract. the digestive tract. The brain controls drinking and feeding behavior. The brain controls drinking and feeding behavior. The brain controls muscles for eating and The brain controls muscles for eating and

elimination. elimination. The digestive system sends sensory information to The digestive system sends sensory information to

the brain. the brain.


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The Reproductive systemThe Reproductive system

Function of the reproductive Function of the reproductive system…system…

The reproductive system is The reproductive system is responsible for producing new life. responsible for producing new life.

Interaction with the nervous system…Interaction with the nervous system…Reproductive hormones affect brain Reproductive hormones affect brain development and sexual behavior. development and sexual behavior. The brain controls mating behavior. The brain controls mating behavior.


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The Urinary systemThe Urinary system

Function of the urinary Function of the urinary system…system…

The urinary system eliminates The urinary system eliminates waste products and maintains waste products and maintains water balance and chemical water balance and chemical balance. balance.

Interaction with the nervous Interaction with the nervous system…system…

The bladder sends sensory The bladder sends sensory information to the brain. information to the brain. The brain controls urination. The brain controls urination.



Diseases of the Nervous Diseases of the Nervous systemsystem

Objectives:Objectives: Alzheimer’s diseaseAlzheimer’s disease Parkinson’s diseaseParkinson’s disease Huntington's diseaseHuntington's disease

Alzheimer’s DiseaseAlzheimer’s Disease Dementia is a brain disorder that seriously affects a Dementia is a brain disorder that seriously affects a person’s ability to carry out daily activities. The most person’s ability to carry out daily activities. The most common form of dementia among older people is common form of dementia among older people is Alzheimer’s disease (AD), which initially involves the Alzheimer’s disease (AD), which initially involves the parts of the brain that control thought, memory, and parts of the brain that control thought, memory, and language. Although scientists are learning more every language. Although scientists are learning more every day, right now they still do not know what causes AD, day, right now they still do not know what causes AD, and there is no cure.and there is no cure. AD is named after Dr. Alois Alzheimer, a German AD is named after Dr. Alois Alzheimer, a German doctor. In 1906, Dr. Alzheimer noticed changes in the doctor. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual brain tissue of a woman who had died of an unusual mental illness. He found abnormal clumps (now called mental illness. He found abnormal clumps (now called amyloid plaques) and tangled bundles of fibers (now amyloid plaques) and tangled bundles of fibers (now called neurofibrillary tangles). Today, these plaques and called neurofibrillary tangles). Today, these plaques and tangles in the brain are considered signs of AD. tangles in the brain are considered signs of AD.

Diseases of the nervous systemDiseases of the nervous system

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Alzheimer’s DiseaseAlzheimer’s DiseaseWhat Causes AD?What Causes AD? Scientists do not yet fully understand what causes AD. There Scientists do not yet fully understand what causes AD. There probably is not one single cause, but several factors that affect probably is not one single cause, but several factors that affect each person differently. Age is the most important known risk each person differently. Age is the most important known risk factor for AD. The number of people with the disease doubles factor for AD. The number of people with the disease doubles every 5 years beyond age 65.every 5 years beyond age 65. Family history is another risk factor. Scientists believe that Family history is another risk factor. Scientists believe that genetics may play a role in many AD cases. For example, early-genetics may play a role in many AD cases. For example, early-onset familial AD, a rare form of AD that usually occurs between onset familial AD, a rare form of AD that usually occurs between the ages of 30 and 60, is inherited. The more common form of the ages of 30 and 60, is inherited. The more common form of AD is known as late-onset. It occurs later in life, and no obvious AD is known as late-onset. It occurs later in life, and no obvious inheritance pattern is seen in most families. However, several inheritance pattern is seen in most families. However, several risk factor genes may interact with each other and with non-risk factor genes may interact with each other and with non-genetic factors to cause the disease. The only risk factor gene genetic factors to cause the disease. The only risk factor gene identified so far for late-onset AD is a gene that makes one form identified so far for late-onset AD is a gene that makes one form of a protein called apolipoprotein E (ApoE). Everyone has ApoE, of a protein called apolipoprotein E (ApoE). Everyone has ApoE, which helps carry cholesterol in the blood. Only about 15 which helps carry cholesterol in the blood. Only about 15 percent of people have the form that increases the risk of AD. It percent of people have the form that increases the risk of AD. It is likely that other genes also may increase the risk of AD or is likely that other genes also may increase the risk of AD or protect against AD, but they remain to be discovered. protect against AD, but they remain to be discovered. Scientists still need to learn a lot more about what causes Scientists still need to learn a lot more about what causes AD. In addition to genetics and ApoE, they are studying AD. In addition to genetics and ApoE, they are studying education, diet, and environment to learn what role they might education, diet, and environment to learn what role they might play in the development of this disease. Scientists are finding play in the development of this disease. Scientists are finding increasing evidence that some of the risk factors for heart increasing evidence that some of the risk factors for heart disease and stroke, such as high blood pressure, high disease and stroke, such as high blood pressure, high cholesterol, and low levels of the vitamin folate, may also cholesterol, and low levels of the vitamin folate, may also increase the risk of AD. Evidence for physical, mental, and social increase the risk of AD. Evidence for physical, mental, and social activities as protective factors against AD is also increasing.activities as protective factors against AD is also increasing.


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Alzheimer’s DiseaseAlzheimer’s DiseaseHow is AD Diagnosed?How is AD Diagnosed?An early, accurate diagnosis of AD helps patients and their An early, accurate diagnosis of AD helps patients and their families plan for the future. It gives them time to discuss families plan for the future. It gives them time to discuss care while the patient can still take part in making care while the patient can still take part in making decisions. Early diagnosis will also offer the best chance to decisions. Early diagnosis will also offer the best chance to treat the symptoms of the disease.treat the symptoms of the disease.Today, the only definite way to diagnose AD is to find out Today, the only definite way to diagnose AD is to find out whether there are plaques and tangles in brain tissue. To whether there are plaques and tangles in brain tissue. To look at brain tissue, however, doctors usually must wait look at brain tissue, however, doctors usually must wait until they do an autopsy, which is an examination of the until they do an autopsy, which is an examination of the body done after a person dies. Therefore, doctors can only body done after a person dies. Therefore, doctors can only make a diagnosis of “possible” or “probable” AD while the make a diagnosis of “possible” or “probable” AD while the person is still alive.person is still alive.At specialized centers, doctors can diagnose AD correctly At specialized centers, doctors can diagnose AD correctly up to 90 percent of the time. Doctors use several tools to up to 90 percent of the time. Doctors use several tools to diagnose “probable” AD, including:diagnose “probable” AD, including:questions about the person’s general health, past medical questions about the person’s general health, past medical problems, and ability to carry out daily activities, problems, and ability to carry out daily activities, tests of memory, problem solving, attention, counting, and tests of memory, problem solving, attention, counting, and language, language, medical tests—such as tests of blood, urine, or spinal fluid, medical tests—such as tests of blood, urine, or spinal fluid, and and brain scans. brain scans. Sometimes these test results help the doctor find other Sometimes these test results help the doctor find other possible causes of the person’s symptoms. For example, possible causes of the person’s symptoms. For example, thyroid problems, drug reactions, depression, brain thyroid problems, drug reactions, depression, brain tumors, and blood vessel disease in the brain can cause tumors, and blood vessel disease in the brain can cause AD-like symptoms. Some of these other conditions can be AD-like symptoms. Some of these other conditions can be treated successfully.treated successfully.


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Parkinson’s DiseaseParkinson’s DiseaseParkinson's disease (PD) belongs to a group of conditions Parkinson's disease (PD) belongs to a group of conditions called motor system disorders, which are the result of called motor system disorders, which are the result of the loss of dopamine-producing brain cells. The four the loss of dopamine-producing brain cells. The four primary symptoms of PD are tremor, or trembling in primary symptoms of PD are tremor, or trembling in hands, arms, legs, jaw, and face; rigidity, or stiffness of hands, arms, legs, jaw, and face; rigidity, or stiffness of the limbs and trunk; bradykinesia, or slowness of the limbs and trunk; bradykinesia, or slowness of movement; and postural instability, or impaired balance movement; and postural instability, or impaired balance and coordination. As these symptoms become more and coordination. As these symptoms become more pronounced, patients may have difficulty walking, pronounced, patients may have difficulty walking, talking, or completing other simple tasks. PD usually talking, or completing other simple tasks. PD usually affects people over the age of 50. In some people the affects people over the age of 50. In some people the disease progresses more quickly than in others. As the disease progresses more quickly than in others. As the disease progresses, the shaking, or tremor, which affects disease progresses, the shaking, or tremor, which affects the majority of PD patients may begin to interfere with the majority of PD patients may begin to interfere with daily activities. Other symptoms may include depression daily activities. Other symptoms may include depression and other emotional changes; difficulty in swallowing, and other emotional changes; difficulty in swallowing, chewing, and speaking; urinary problems or chewing, and speaking; urinary problems or constipation; skin problems; and sleep disruptions. constipation; skin problems; and sleep disruptions. There are no blood or laboratory tests available to There are no blood or laboratory tests available to diagnose PD. diagnose PD.


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Parkinson’s DiseaseParkinson’s Disease

Is there any treatment?Is there any treatment? At present, there is no cure for PD, but a variety of At present, there is no cure for PD, but a variety of medications provide dramatic relief from the medications provide dramatic relief from the symptoms. Usually, patients are given levodopa symptoms. Usually, patients are given levodopa combined with carbidopa. Carbidopa delays the combined with carbidopa. Carbidopa delays the conversion of levodopa into dopamine until it reaches conversion of levodopa into dopamine until it reaches the brain. Nerve cells can use levodopa to make the brain. Nerve cells can use levodopa to make dopamine and replenish the brain's dwindling dopamine and replenish the brain's dwindling supply. Although levodopa helps at least three-supply. Although levodopa helps at least three-quarters of parkinsonian cases, not all symptoms quarters of parkinsonian cases, not all symptoms respond equally to the drug. Bradykinesia and rigidity respond equally to the drug. Bradykinesia and rigidity respond best, while tremor may be only marginally respond best, while tremor may be only marginally reduced. Problems with balance and other symptoms reduced. Problems with balance and other symptoms may not be alleviated at all. Anticholinergics may may not be alleviated at all. Anticholinergics may help control tremor and rigidity. Other drugs, such help control tremor and rigidity. Other drugs, such as bromocriptine, pergolide, pramipexole, and as bromocriptine, pergolide, pramipexole, and ropinirole, mimic the role of dopamine in the brain, ropinirole, mimic the role of dopamine in the brain, causing the neurons to react as they would to causing the neurons to react as they would to dopamine. An antiviral drug, amantadine, also dopamine. An antiviral drug, amantadine, also appears to reduce symptomsappears to reduce symptoms


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Huntington’s DiseaseHuntington’s Disease In 1872, the American physician George In 1872, the American physician George Huntington wrote about an illness that he called Huntington wrote about an illness that he called "an heirloom from generations away back in the "an heirloom from generations away back in the dim past." He was not the first to describe the dim past." He was not the first to describe the disorder, which has been traced back to the Middle disorder, which has been traced back to the Middle Ages at least. One of its earliest names was Ages at least. One of its earliest names was chorea,* which, as in "choreography," is the Greek chorea,* which, as in "choreography," is the Greek word for dance. The term chorea describes how word for dance. The term chorea describes how people affected with the disorder writhe, twist, and people affected with the disorder writhe, twist, and turn in a constant, uncontrollable dance-like turn in a constant, uncontrollable dance-like motion. Later, other descriptive names evolved. motion. Later, other descriptive names evolved. "Hereditary chorea" emphasizes how the disease is "Hereditary chorea" emphasizes how the disease is passed from parent to child. "Chronic progressive passed from parent to child. "Chronic progressive chorea" stresses how symptoms of the disease chorea" stresses how symptoms of the disease worsen over time. Today, physicians commonly worsen over time. Today, physicians commonly use the simple term Huntington's disease (HD) to use the simple term Huntington's disease (HD) to describe this highly complex disorder that causes describe this highly complex disorder that causes untold suffering for thousands of families.untold suffering for thousands of families.


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What Causes Huntington's Disease?What Causes Huntington's Disease? HD results from genetically programmed degeneration of HD results from genetically programmed degeneration of nerve cells, called neurons,* in certain areas of the brain. This nerve cells, called neurons,* in certain areas of the brain. This degeneration causes uncontrolled movements, loss of intellectual degeneration causes uncontrolled movements, loss of intellectual faculties, and emotional disturbance. Specifically affected are faculties, and emotional disturbance. Specifically affected are cells of the basal ganglia, structures deep within the brain that cells of the basal ganglia, structures deep within the brain that have many important functions, including coordinating have many important functions, including coordinating movement. Within the basal ganglia, HD especially targets movement. Within the basal ganglia, HD especially targets neurons of the striatum, particularly those in the caudate nuclei neurons of the striatum, particularly those in the caudate nuclei and the pallidum. Also affected is the brain's outer surface, or and the pallidum. Also affected is the brain's outer surface, or cortex, which controls thought, perception, and memory. cortex, which controls thought, perception, and memory. What are the Major Effects of the Disease?What are the Major Effects of the Disease? Early signs of the disease vary greatly from person to person. Early signs of the disease vary greatly from person to person. A common observation is that the earlier the symptoms appear, A common observation is that the earlier the symptoms appear, the faster the disease progresses. Family members may first the faster the disease progresses. Family members may first notice that the individual experiences mood swings or becomes notice that the individual experiences mood swings or becomes uncharacteristically irritable, apathetic, passive, depressed, or uncharacteristically irritable, apathetic, passive, depressed, or angry. These symptoms may lessen as the disease progresses or, angry. These symptoms may lessen as the disease progresses or, in some individuals, may continue and include hostile outbursts or in some individuals, may continue and include hostile outbursts or deep bouts of depression. deep bouts of depression. The disease can reach the point where speech is slurred and vital The disease can reach the point where speech is slurred and vital functions, such as swallowing, eating, speaking, and especially functions, such as swallowing, eating, speaking, and especially walking, continue to decline. Some individuals cannot recognize walking, continue to decline. Some individuals cannot recognize other family members. other family members.

Diseases of the nervous system, Parkinson’s diseaseDiseases of the nervous system, Parkinson’s disease

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Is There a Treatment for HD?Is There a Treatment for HD? Physicians may prescribe a number of medications to Physicians may prescribe a number of medications to help control emotional and movement problems help control emotional and movement problems associated with HD. associated with HD. Antipsychotic drugs, such as haloperidol, or other Antipsychotic drugs, such as haloperidol, or other drugs, such as clonazepam, may help to alleviate choreic drugs, such as clonazepam, may help to alleviate choreic movements and may also be used to help control movements and may also be used to help control hallucinations, delusions, and violent outbursts. hallucinations, delusions, and violent outbursts. Antipsychotic drugs, however, are not prescribed for Antipsychotic drugs, however, are not prescribed for another form of muscle contraction associated with HD, another form of muscle contraction associated with HD, called dystonia, and may in fact worsen the condition, called dystonia, and may in fact worsen the condition, causing stiffness and rigidity. These medications may also causing stiffness and rigidity. These medications may also have severe side effects, including sedation, and for that have severe side effects, including sedation, and for that reason should be used in the lowest possible doses. reason should be used in the lowest possible doses. For depression, physicians may prescribe fluoxetine, For depression, physicians may prescribe fluoxetine, sertraline, nortriptyline, or other compounds. Tranquilizers sertraline, nortriptyline, or other compounds. Tranquilizers can help control anxiety and lithium may be prescribed to can help control anxiety and lithium may be prescribed to combat pathological excitement and severe mood swings. combat pathological excitement and severe mood swings. Medications may also be needed to treat the severe Medications may also be needed to treat the severe obsessive-compulsive rituals of some individuals with HD. obsessive-compulsive rituals of some individuals with HD. Most drugs used to treat the symptoms of HD have Most drugs used to treat the symptoms of HD have side effects such as fatigue, restlessness, or side effects such as fatigue, restlessness, or hyperexcitability. Sometimes it may be difficult to tell if a hyperexcitability. Sometimes it may be difficult to tell if a particular symptom, such as apathy or incontinence, is a particular symptom, such as apathy or incontinence, is a sign of the disease or a reaction to medicationsign of the disease or a reaction to medication.

Diseases of the nervous system, Parkinson’s diseaseDiseases of the nervous system, Parkinson’s disease


referencesreferences* Books:* Books:- Essentials of human anatomy and physiology- Essentials of human anatomy and physiology

by: Elain N. Marieb.by: Elain N. Marieb.* Websites:* Websites:- - http://faculty.washington.edu/chudler/sagittal.htmlhttp://faculty.washington.edu/chudler/sagittal.html

- - www.alzheimers.org/pubs/adfact.htmlwww.alzheimers.org/pubs/adfact.html- - http://www.ninds.nih.gov/disorders/parkinsons_disease/parkinsons_disease.htmhttp://www.ninds.nih.gov/disorders/parkinsons_disease/parkinsons_disease.htm

- - http://www.ninds.nih.gov/disorders/huntington/detail_huntington.htm#17353137http://www.ninds.nih.gov/disorders/huntington/detail_huntington.htm#17353137- http://www.wekipedia.org- http://www.wekipedia.org* Essential of interactive physiology CD.* Essential of interactive physiology CD.

ClosureClosureI hope that you have enjoyed this I hope that you have enjoyed this

material.. material.. Thank youThank you

Created by:Created by: Yasmeen Hani Arafsha Yasmeen Hani ArafshaCollage:Collage: Applied Medical Science Applied Medical Science

College number:College number: 425201717 425201717

PS.:PS.:I would be appreciative if you call me for commentary I would be appreciative if you call me for commentary Phone: 0502997548Phone: 0502997548