Nervous systemsarah park & jenny youn

Contents

Structure and function of neuron

Divisions of nervous system (central vs. peripheral, autonomic vs. somatic, sympathetic vs. parasympathetic

Parts of brain and functions of each

Emotions and the amygdale

Importance of reflexes to our well-being

Current issues: stem cells and spinal cord injuries

Emotions & AMYGDALA

-BRAIN AND EMOTION- Autonomic nervous System

AMygdala

Your autonomic nervous system has two branches of activity.

FIGHT FLIGHT

The sympathetic branch

Heart Rate (+)PREPARE FOR ACTION

Emotion and the amygdala

Your autonomic nervous system has two branches of activity.

PARASYMPATHETICBRANCH

Heart rate (-)REST AND RECOVERY

EMotion and the Amygdala

Stimulate: hormonal production & response.

Manifestations of autonomic nervous system imbalance common symptoms

-headache, hot flash, irregular heartbeat, nervousness, depression, anxiety

Emotion and the Amygdala

WHAT IS THE AMYGDALA?

•Set of sub-cortical nuclei •Perceive in others and having in oneself emotional or affective behaviors & feelings

IT IS, THEREFORE, a component of the limbic system.

amygdala

<- LOCATION OF THE AMYGDALA IN THE BRAIN.

<- SUBDIVISION OF THE AMYGDALA

reflexes to our well-being

•Philosophy – good for a person•What does our well-being consist of?

-depends on independent interests-important in moral philosophy

Reflexes to our well being

Welfarism

-justifactory force of any moral reason rests on well-being

Current Issue: stem cells

• Potential for self-renewal & to differentiate into specialized cell types

• Early Mammalian Embryo (5-7 days)

-give rise to different cell types of organism

Spinal Cord Injuries•myelopathy, damage to white matter, myelinated fiber tracts (carry signals

to&from brain)•Gray matter (central spine part) – segmental loss of inter-neurons and motor-neurons•Causes: trauma, tumor, ischemia, development disorders, neuro-degenerative diseases, vascular malformations, transverse myelits, demyelinative diseases

how various drugs and alcohol affect our nervous system

COCAINE

•Increased energy, decreased appetite, mental alertness •Highly addictive•Disturbs heart rhythm, nausea, respiratory failure, strokes, seizures•Severe withdrawal symptoms when user stops taking this drug

MARIJUANA

MARIJUANA CAUSES A PEACEFUL OR EUPHORIC SENSATION IN THE USER.

SOON THE SENSATION PASSES AND THE USER MAY FEEL SLEEPY OR DEPRESSED.

MARIJUANA IMPAIRS MEMORY AND ATTENTION SPAN. IT ALSO AFFECTS COORDINATION AND

BALANCE AND SLOWS REACTION TIME.

Heroin

HEROIN IS EXTREMELY ADDICTIVE. SYMPTOMS OF WITHDRAWAL AFTER STOPPING HEROIN USE INCLUDE RESTLESSNESS, MUSCLE AND BONE PAIN, INSOMNIA,

DIARRHEA, VOMITING AND COLD FLASHES.

HEROIN CAUSES A ‘RUSH’ OF PLEASURE IN THE USER THAT IS USUALLY FOLLOWED BY SEVERAL HOURS OF

DROWSINESS. IT MAY ALSO CAUSE NAUSEA, VOMITING AND SEVER ITCHING.

Hallucinogens

HALLUCINOGENS ARE DRUGS THAT CAUSE HALLUCINATIONS - DISTORTIONS IN

PERCEPTION OF REALITY AND TIME. THEY MAY EXPERIENCE SEVERAL EMOTIONS AT

ONCE OR SWING RAPIDLY FROM ONE EMOTION TO ANOTHER.

Nervous system disease

http://www.sci.uidaho.edu/med532/Disease_index.htm

http://www.umm.edu/nervous/glossary.htm

Neurons

• Neurons, glial cells

• Roles: transmit nerve messages

• Glial Cells- surround & have contact with neurons Functional unit of nervous system

• 100 billion in brain

• 3 parts : Dendrites, cell body, axon

Neurons~

Neurons cont.

• Dendrites – receive info from cell and transmit message to cell body

• Cell body – eukaryote cells (mitochondria, nucleus, etc.)

• Axon – conduct message away from cell body

Peripheral Nervous System (PNS)

• Contains nerves

• connects the brain & spinal cord to rest of the body

• Dendrites and axons (surrounded by white myelin sheet)

• cell bodies – central nervous system (ganglia)

• Ganglia : collections of nerve cell bodies

• Spinal nerves – take impulses to & away from the spinal cord

• two major subdivisions of PNS motor pathways: somatic, autonomic.

<CONT>

• Two main components of the PNS:

• sensory (afferent) pathways that provide input from the body into the CNS.a

• motor (efferent) pathways that carry signals to muscles and glands (effectors)

• Most sensory input carried in the PNS remains below the level of conscious awareness. Input that does reach the conscious level contributes to perception of our external environment.

Central Nervous System

• Made up of spinal cord, brain

• SPINAL CORD

-Conducts sensory info. From PNS (both somatic & autonomic) to the brain conducts motor info. (from brain to various effectors)

-Skeletal muscles, cardiac muscle, smooth muscle, glands

-Serves as minor reflex center

CNS (cont)

• BRAIN

-Receives sensory input from spinal cord & nerves

-<Ex> olfactory & optic nerves devotes most of its volume and computational power to processing its various sensory inputs and initiating appropriate – and cooridinated – motor outputs

Sympathetic

• Autonomatic (can’t be controlled by mind)

• Allows body to function under stress

• Fight/flight

Parasympathetic

• Autonomatic (can’t be controlled by mind)

• Controls vegetative functions

-Feed/ breed/ rest, and repose

• Constant opposition to sympathetic system

Skeletal System

• Bones provide calcium that is essential for the proper functioning of the nervous system.

• skull protects brain

• sensory receptors in joints between bones send signals about body position to brain

• brain regulates position of bones by controlling muscles

• vertebrae protect spinal cord

Muscular System

• Receptors in muscles provide the brain with information about body position and movement.

• brain controls contraction of skeletal muscle.

• nervous system regulates heart rate and speed at (food moves through the digestive tract.)

Endocrine System

• Hormones provide feedback to the brain to affect neural processing.

• Reproductive hormones affect the development of the nervous system.

• The hypothalamus controls the pituitary gland and other endocrine glands.

Reproductive System

• Reproductive hormones affect brain development and sexual behavior.

• The brain controls mating behavior.

Urinary System

• The bladder sends sensory information to the brain.

• The brain controls urination.

Injuries

• Concussions

-Bruiselike injury of brain

• Spinal Cord Injuries

-Axons damaged, impulses can’t pass through them

Brain

• Cerebrum, cerebellum, brain system

• Forebrain

• Largest, most complex part

• Midbrain

• master coordinator for all the messages going in and out of the brain to the spinal cord

• Hindbrain

• responsible for balance, movement, and coordination

Sight

• Light enter eye forms an upside-down image on the retina

• transforms the light into nerve signals for the brain

• Brain turns the image right-side up and tells us what we are seeing.

Hearing

• Waves enter causing eardrums to vibrate

• then transferred along tiny bones of the middle ear & converted into nerve signals

• Cortex : processes these signals, telling us what we are hearing.

Taste

• Taste Buds

-Small group of sensory cell in tongue

-react to chemicals in foods

• sweet, sour, salty, bitter.

• Messages sent from taste buds to areas in the cortex responsible for processing taste.

Smell

• Olfactory cells in the mucous membranes lining each nostril react to chemicals we breathe in & send messages along specific nerves to the brain

• distinguish between more than 10,000 different smells

• smells are very closely linked to our memories.

Touch

• The skin contains +4 million sensory receptors — mostly concentrated in the fingers, tongue, and lips

-gather information related to touch, pressure, temperature, and pain

-Then send it to the brain for processing & reaction.

Bibliography

http://en.wikipedia.org/wiki/Spinal_cord_injury

http://www.massagetoday.com/mpacms/mt/article.php?id=13725

“Fifth edition in modules”- David College, 10th grade psychology textbook.

www.cgkp.org.uk/resources/pdf/stem_cell_paper2.pdf

http://plato.stanford.edu/entries/well-being/

Cont.

• http://kidshealth.org/parent/general/body_basics/brain_nervous_system.html

• http://faculty.washington.edu/chudler/organ.html

• http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookNERV.html#Peripheral%20Nervous%20System

• http://faculty.washington.edu/chudler/introb.html

• http://yucky.discovery.com/flash/body/pg000136.html

Cont.

• http://en.wikipedia.org/wiki/Human_brain

• http://kidshealth.org/kid/htbw/brain.html

• http://www.innerbody.com/image/nerv08.html

• http://library.thinkquest.org/5777/ner1.htm

• http://training.seer.cancer.gov/module_anatomy/unit5_1_nerve_functions.html