The Nervous System

The Nervous SystemWilliam P. Wattles, Ph.D.Francis Marion UniversityPsy 314 Behavioral Medicine#

#Brianna LaHara a 12-year-old New York City girl was frightened to learn she was among the hundreds of people sued yesterday by giant music companies in federal courts around the country. "I got really scared. My stomach is all turning," Brianna said last night at the city Housing Authority apartment where she lives with her mom and her 9-year-old brother.

#Sympathetic Nervous systemIf an animal is under threat, for whatever reason, its sympathetic nervous system is activated.The activation occurs virtually instantaneously.#The Nervous SystemText says that the basic function of the nervous system is to integrate all the bodys systems. The nervous system is made up of nerve cells or neurons.afferent (sensory) neuronsefferent (motor) neuronsInterneurons #NeuronsDendriteCell BodyAxonNeurons dont touch They communicate via neurotransmitters, chemicals that cross the synaptic cleft (space between neurons)#Synaptic TransmissionNerve Impulse A brief electrical charge that travels down an axonGenerated by the movement of positively charges atoms in and out of channels in the axons membraneAll-or-none responseThreshold The level of stimulation required to trigger a neural impulse#Synaptic TransmissionSynapse [SIN-aps]Junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuronMay be excitatory or inhibitoryNeurotransmittersChemical messengersReleased by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether it will generate a nerve impulse#Synaptic Transmission

#Subdivisions of the vertebrate nervous system (page 111)Central Nervous SystemBrainSpinal CordPeripheral Nervous SystemSomatic nervous SystemAutonomic Nervous SystemSympathetic divisionParasympathetic division

#Somatic Nervous SystemControls voluntary musclesConsists of nerves that:convey sensory messages to the CNSconvey messages from the CNS to muscles and glands#Autonomic Nervous SystemAutonomic means self-governingReceives information from and sends messages to the heart, intestines and other organs. Sympathetic and parasympathetic systems operate in opposition to each other.#Autonomic Nervous SystemSympathetic DivisionParasympathetic Division#

Autonomic arousal#Sympathetic Nervous SystemPrepares the body for intense, vigorous, emergency actionThe fight or flight responseHeart and breathing rate increasesMental activity increasesDigestion decreasesBlood flow increases to the skeletal muscles#The Fight or Flight ResponsePassed down via evolutionSurvival of the fittestAdaptive-enhances the survival of the organismAbility to focus bodys resources in time of danger is adaptive.More likely to live long enough to have progeny and raise those progeny.#Animal that averages 2 offspring8 in 3 generations

#Animal that averages 3 offspring27 in 3 generations

#Sympathetic arousal or the stress responseThe mind must be able to influence the body for survival.Stress is a mental/emotional reaction to a threat or challenge.Adaptive in nature where we face relatively rare threats to our survival#

#Parasympathetic Nervous SystemPromotes relaxation and functions under normal conditions.#Parasympathetic Nervous SystemIncreases digestionPromotes processes associated with relaxationConserves energyAllows body to restore itself#

Daily HasslesExperiences of daily living that have been appraised as salient and harmful or threatening to our well being.

#Selyes View of StressSelye views stress as a response and Stressor is a stimulusGeneral Adaptation syndromealarm stageresistanceexhaustion stage#Alarm stateFight or Flight responseBody is prepared for anything

#Resistance StageBody adapts to the stressor. Physiologically the bodys internal functioning is not normal#Exhaustion StateAbility to resist is depleted, depression even death can result.#

Perception of stress#Lazrus model of stressReaction is dependent upon how demands are perceived, evaluated and appraised. The same demands can therefore mean challenge for one person yet pose a threat to another.

#Lazarus transactional positionEffect of a stressor based on the perception of:threatvulnerabilityability to copeIt is not the life event but ones view of it that determines the level of stress.#

#Primary appraisalWhen confronted with a stressor people make a fist or initial appraisal.A stressful appraisal involves:threatharmchallenge#Secondary appraisalWhat options are available?How likely am I to be able to apply the necessary strategies?Will the procedure work?

#ReappraisalCan lead to greater or less stress.#Lazrus model of stressVulnerability determines the effect of stressors.Coping a processlearnedeffortfulan effort to manage the situation#Stress but not for allTennes and Kreye, 1985Some children had elevated levels of Cortisol and test day but some did not.

Tennes and Kreye, 1985#HardinessThe ability to withstand stresshealth and energypositive belief (self-efficacy)problem-solving skillssocial skillssocial supportmaterial resources#Endocrine systemWorks with the nervous systemReleases hormones which are carried in the blood streamHormones are slower to reach their target and last longer.#Adrenal glandsLocated on the kidneysproduce Cortisol a hormone used to measure levels of stressalso produce epinephrine sometimes called adrenaline.#Sources of StressCrowding-density versus crowdingPollutionNoiseUrban Press-road rageOccupation-school pressurepersonal relationshipssleep problems

#100 Death of spouse73 Divorce65 Marital separation63 Jail Term63 Death of family member53 Personal injury or illness50 Marriage47 Fired at Work45 Marital Reconciliation45 Retirement40 Pregnancy

25 Change in living conditions24 Revision of personal habits23 Trouble with boss20 Change in work hours20 Change in residence19 Change in recreation19 Change in church activities18 Change in social activities17 Personal loan16 Change in sleeping habits13 Vacation12 Christmas or ChanukahSocial Readjustment Rating Scale

#Percentage of People with Illness

#Measuring life stressSocial Readjustment Rating Scale much criticized.Everyday hassles scale. HasslesUplifts

#Hassles and Uplifts ScaleSupports Lazruss contention that perception of an event more important than the event.

#Stress and the heartParasympathetic nervous system control the heart at rest with a heart rate as low as 20-30 beats per minuteSympathetic Nervous system can push the heart rate up to 250 bpm. Sudden cardiac death and arrhythmias important in those with heart disease#The Vascular Systemvascoconstriction-muscles around the arteries, arterioles and veins constrict reducing blood flow.vasodilatation-The opposite process when vessels dilate or open to allow more blood flowthe stress response redirects blood to deep muscles needed for fight or flight#Cardiovascular disorders related to stressAngina pectoris-Severe paroxysmal pain in the chest associated with an insufficient supply of blood to the heartAtherosclerosis-plaque build-up impair blood circulation. major cause of death in the U.S.Essential hypertension-High blood pressure. Above 140/90#Migraine headachesDebilitating headaches related to vascular constriction.Classical-preceded by an auracommon to warningTriggered by certain foods and/or stressMay be more common in those who are perfectionistic, compulsive and overly responsible.#Blood PressureSystolic-maximum pressure in the arteries as the heart beatsDiastolic-minimum pressure as the hear is filling.BP recorded as systolic/diastolic120/80 generally considered optimalImportant risk factor in cardio-vascular illness#Gastrointestinal systemFunctions in absorption of nutrients and elimination of wastes.Digestion begins with anticipation of eatingGenerally the activity of the GI system is unnoticed.Designed to shut down during stress#Gastrointestinal problemsUlcers -sores on the mucus lining of the stomachIrritable Bowel Syndrome-aka spastic colon. Pain, diarrhea, constipation, bloating and gasColitis-inflammation of the colon#Social SupportFour types identified:EmotionalComfort and listeningAppraisalSuggestions improve performanceInformationalKnowledge shared about better medsInstrumental Baby-sit so you can see doctor

#Dose Response Relationship

A direct, consistent association between an independent variable, such as a behavior, and a dependent variable, such as a disease.#Dose ResponseDescribes how a response variable--a biological measurement or epidemiologic population statistic--depends on the level of dose.

Industrial noise and BPMedication and BP

#Requirements for Reaction PaperMinimum two pages. 1 pages is not 2 pages. Typed double-spaced standard font 10 or 12.Free of grammar and spelling errorsPaper must be about your reactions to the story. NOT a synopsis of the article. #

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