Human Behaviour (2)

8/13/2019 Human Behaviour (2)

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HUMAN BEHAVIOUR AND LIFE PROCESSESS

INTRODUCTION

Our brain is considered as most complex organ and centre piece of nervous system. Our brainis divided into three interconnected layers- central core, limbic system and cerebral cortex whichregulate the everydays activities. Brain is physical organ like muscles and bone, the brain isunique and it is psychological organ, ultimately responsible for our moods of despair andelation, our sense of wellbeing and our sensation, perception of outside world and ourawareness of its meaning. e must trace, if we have to gain a meaningful understanding of ourpersonality and why we behave as we do.

STRUCTURE OF NEURON

Brain is !the psychological organ it gives rise to the mind that is to mental processes "such asperception, memory and language# and mental experiences. $ll the brain activities are carriedby neurons or brain cells. %here are three types of neurons&-

'ensory neurons, respond to input from senses

(otor neurons, sends signals to muscles to control movements

)nterneuron stands between the neurons that register whats out there and those thatcontrol movements.

*ach neuron has certain parts&-

%he central part of a neuron is called the cell body. )t has a nucleus, which regulates cellssfunction and a cell membrane, which is the skin of the cell. %he sending end of neuron is the

$+O , the long cable like structure extending from cells body, along which signals travel toother neurons, muscles or bodily organs. *ach neuron has only a single axon. (ost axons hasmany branches called %* () $ ', so that a neuron can send a message to more than oneplace at a time. $t the ends of the terminals are %* () $ B/%%O ', little knob likestructures that release chemicals into space between neurons when neurons has beentriggered. (ost of neurons, communicate by releasing chemicals called neurotransmitters thataffect other neurons, usually at their receiving end. *ach neuron has only one sending end thatonly have one axon, but having many receiving ends called 0* 0 )%*'. 0endrites receivemessages from the axons of other neurons.

ACTION POTENTIAL

euron at rest have to maintain negative charge within them called resting potential. 0uringrest, more positively charged ions called cations and sodium ion are outside than inside andmore negatively charged are inside the neurons , membranes covering the axon has very smallholes or pores called 12$ * ' , which open and close . hen neuron receives enoughstimulation from other neurons, some of channels open, allowing exchange of ions that changescharge in the axon. %his exchange moves down towards terminal buttons.

hen a neuron is resting and not conducting a nerve impulse, the inside of cell has negativecharge. $ stimulus which excites the cell will make the inside charge a little less negative. $trest , sodium ions cannot enter because even though the cell membrane is permeable , theopenings are too small at this time for big sodium ions to enter .when cell receives strong


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stimulation from other cell, the cell membranes opens up the special gates, one after the other ,allowing the sodium ions to rush into cell .this causes inside the cell ,positive and outside of thecell to become negative. %his electrical reversal changes is called action potential. )t takes 3 of3444 th second , so the neural message travel very fast from 5 miles per hour in the slowest and564 miles per hour in other neurons. %his action potential travelling down the axon. $fter theaction potential passes, the cell membrane !pumps out the sodium ions back outside the celland closing the gates until next action potential comes.

SYNAPSE AND THEIR FUNCTIONS

%he ends of axons actually reaches out several branches called axon terminals. %he tip of eachterminal has a little knob called synaptic knob or terminal buttons. )t has number of little sac likestructures called '7 $8%)1 9*')1 *'. )nside the synaptic vesicles, are the chemicalssuspended in fluid called neurotransmitters. Between terminal buttons and dendrites of anotherneuron, there is fluid filled space called '7 $8'* or synaptic gap. 'ynaptic vesicles containneurotransmitter molecules whereas dendrites of next neuron contain *1*8%O ')%*'. %heyhave particular shape allows only a particular neurotransmitter to fit into it. hen electricalcharge reaches the synaptic vesicles, they release their neurotransmitters into the synaptic gap.

(olecules float and many fit into the receptor sites, activating the next cell.

NEUROTRANSMITTERS

eurochemists and pharmacologists have identified a number of neurotransmitters at synapse.

$1*%7 *12O ) *&- it is the neurotransmitter found at the synapse betweenneurons and muscle cells. )f acetylcholine receptors sites on the muscle cells areblocked in some way, then muscle will be paraly:ed or unable to contract

;$B$"g.aminobutyric acid#&- it is the common inhibitory neurotransmitter in thebrain . ;$B$ can help to calm anxiety.

'* O%O ) &- it is a neurotransmitter found in the lower part of the brain and it canact as an excitory or inhibitory chemical depending upon its location in the area ofbrain . it is mainly associated with mood , sleep and appetite. ower levels ofserotonin are linked with depression.

0O8$() *&- it is found in the brain and have different effects depending upon itslocation. )f too little dopamine is released in a certain area of brain, it results in8arkinsons disease and too much dopamine results in '12)


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*/ O% $ '()%%* ' =/ 1%)O '

3. $cetylcholine

5. 'erotonin

>. ;$B$?. ;lutamate

@. or epinephrine

A. 0opamine

6. endomorphins

)nvolved in memory and movement

)nvolved in mood, sleep and appetite.

(ainly involved in sleep.)n memory formation.

)n arousal and mood.

)n the control of movements andpleasure.

)nvolved in pain relief.

REUPTAKE OF NEUROTRANSMITTERS

One method of deactivation is by catalysts called en:ymes, which triggers chemicalreactions those breakup neurotransmitters molecules.

'econd method is by process of reuptake. in this process, terminal buttons take back therelease neurotransmitters and store it in vesicles for use for next time

0rugs mainly psychoactive drugs may interfere with synaptic transmission.

FUNCTION OF CENTRAL NERVOUS SYSTEM IN BEHAVIOUR

%he central nervous system is composed of the brain and spinal cord .both brain and spinalcord are made of neurons and glial cells that control the life sustaining functions of body as wellas thought , emotions and behavior.

%2* B $) & - brain is the true core of nervous system , the part that takes information receivedfrom the senses, makes sense out of it, makes decisions and sends commands out to themuscles and the rest of the body.

%2* '8) $ 1O 0&- it is a long bundle of neurons that serves two vital functions the nervoussystem.

%o carry messages from body up to the brain and

=rom the brain down to the body

)t is divided into two areas- outer and inner. Outer region is composed mainly of axons andnerves, which appear white and inner section is mainly composed of cell bodies of neuronswhich appear grey.


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REFLEX ARCH

)nner section of spinal cord is made up of cell bodies separated by glial cells. %his part isresponsible for the certain reflexes -very fast and life saving reflexes. (ainly three types ofneurons are responsible for reflex action- sensory, motor and interneurons. %hese kind ofresponse are controlled by spinal cord along for fast response.

BRAIN STEM, CEREBELLUM AND RETICULAR FORMATION(CENTRAL CORE)

Brain stem consists of four divisions&- the medulla, the pons and the midbrain. %hese all help tocontrol and regulate many bodily functions like breathing , temperature regulation etc which arenecessary for life.

1erebellum is the brains large, complex structure. )t receives sensory and other inputs fromspinal cord , brain stem and forebrain. )t processes this information and then send output tomany parts of brain to help to make our movements precise, coordinated and smooth and alsohelps to control posture and maintains equilibrium.

eticular formation is a complex region from medulla to the midbrain and contains many small

clumps of neurons and a number of long and short nerve fibers. )t helps in activation andarousal of the cerebral cortex and remains active during sleep. )t also helpful in various degreesof arousal from deep sleep state to alert awareness of the environment. )f this region isdestroyed , a deep sleep state may occurs Cust like coma.

8ons triggers dreaming and waking up from sleep.

(edulla is a centre of breathing, waking, sleeping and beating of heart.

FOREBRAIN: THALMUS (LIMBIC SYSTEM)

Dust above the midbrain, a kind of expanded bulb on top of the brain stem called thalamus. )tlies between the two cerebral hemispheres and is covered by them. %heir main function is toreceive main inputs from other nuclei within itself and then send fibers to the cortex. %his canalso transform and modify input before sending it on the cerebral cortex.

FOREBRAIN HYPOTHALMUS AND PITUTARY

ying below the thalamus, there is a small but vital area of the forebrain known ashypothalamus. )ts importance is that it contains nuclei which are related to motivated behavior.

=/ 1%)O '&- 3. )t receives reports about state of internal environment from the other bodilyorgans. hen internal environment change from their homeostatic level, certain hypothalamic

neurons become active and sends information to the pituitary gland. )t monitors tha bloodglucose and salt level, blood pressure and hormones.

5. 2ypothalamus is also means of nerve impulses sent to pituitary or by chemicals called2O (O *' or releasing factors.

>. sexual and maternal behavior and learning and memory are the important functions ofpituitary gland.


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CEREBRAL CORTEX

=O *B $) &-it weighs about 3?44gms and divided into two cerebral hemisphere and furtherinto different lobes. %hese have an important role to play in regulation and control ofmovements. 9arious regions of cerebrum have different functions to movement of specific partsof body.

)t can control bodily movements and play an important role in the regulation and controlof movement.

1erebral cortex has motor and sensory functions. (otor areas are concerned for bodilymovements and other areas.

0amage of these parts may result in partial paralysis or complete paralysis of wholebody.

FRONTAL AREA- PERSONALITY AND GENERAL BEHAVIOUR PATTERN

)t assists in motor control and cognitive activities such as decision making, planning and setting

goals. %wo different types of personality changes follow prefrontal lobe damage. )t includes lackof impulsiveness, immaturity in social relationship, and loss of initiative, decrease inspontaneous talking, reduced emotional expressions are main features. )ntellectual changesinclude lack in direction of behavior, inflexibility and memory impairment, problems in planning,and remembering the order of recent events.

TEMPORAL LOBE ASSOCIATION CORTEX

%he temporal lobe of each hemisphere lies below the lateral fissure in cerebral cortex. )ts mainfunctions are hearing and language.

'ensory functions&- 3. )t is involved in hearing, perception and recognition of sounds. 0ifficultyin recogni:ing problems or melodies may result from damage to temporal lobe associationcortex. )t helps in auditory perception and visual recognition.

5. 0amage also results in impaired sensation and trouble in indentifying pictures of commonobCects and recogni:ing facts.

anguage functions&- left temporal lobe contains a region of association cortex called E* )1F' areaG. 0amage to this region may result in impairment of understanding of speechand written language.

LEFT HEMISPHERE AND ITS FUNCTIONS

eft hemisphere is usually speciali:ed for language functions. 'troke typically affects one sideof brain and produce paralysis of one side of body opposite that of affected side of brain. )f weknow which side is paraly:ed, we can know that brain damage is in cerebral hemisphere ofopposite side of paralysis.

=unctions& - their main functions are locali:ed in * )1Fs area. 0amage to this area resultsin language problems


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RIGHT HEMISPHERE AND ITS FUNCTIONS

ight hemisphere seems to have an advantage in recognition faces and remembering things inrelation to each other. )ts main function is to verbally report the information and speechorgani:ed in left hemisphere.

LIFE PROCESSESS

%he word life processes means the processes take place in the human bodies which areneeded for the existence of life on *arth. =or example 0igestion, respiration, excretion,reproduction, etc. Basically main life processes are sleep, stress and homeostatic mechanism.

3. Hom o!"#"$% M %'$!m! o o*+

2omeostatic mechanisms control a property of all living things called homeostasis. 2omeostasisis a built-in, automated, and essential property of living systems. Breathing is an example of ahomeostatic property. 2omeostatic mechanisms are self-regulating mechanisms that function tokeep a system in the steady state needed for survival. %hese mechanisms counteract theinfluences that drive physiological properties towards a more unbalanced state 1onditions thatare regulated in homeostasis include blood glucose level, temperature, water content of thebody, and the amount of carbon dioxide and urea being carried by the blood.

DEFINITION

2omeostasis, from the ;reek words for HsameH and Hsteady,H refers to any process that livingthings use to actively maintain fairly stable conditions necessary for survival.

I'" '# %om.o' '"! o &om o!"#!$!

3. 1oncentration of oxygen and carbon dioxide

5. p2 of the internal environment

>. 1oncentration of nutrients and waste products

?. 1oncentration of salt and other electrolytes

@. 9olume and pressure of extracellular fluid

Components of a homeostatic mechanism

Stimulus Receptors

Control Center

EffectorsResponse


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Co'" o S+!" m! o &om o!"#!$!

*xtrinsic

(ost homeostatic systems are extrinsic& they are controlled from outside the body.*ndocrine and nervous systems are the maCor control systems in higher animals.

%he nervous system depends on sensors in the skin or sensory organs to receive stimuli

and transmit a message to the spinal cord or brain. 'ensory input is processed and a signalis sent to an effector system, such as muscles or glands, that effects the response to thestimulus.

%he endocrine system is the second type of extrinsic control, and involves a chemicalcomponent to the reflex. 'ensors detect a change within the body and send a message toan endocrine effector "parathyroid#, which makes 8%2. 8%2 is released into the blood whenblood calcium levels are low. 8%2 causes bone to release calcium into the bloodstream,raising the blood calcium levels and shutting down the production of 8%2.

'ome reflexes have a combination of nervous and endocrine response. %he thyroid glandsecretes thyroxin "which controls the metabolic rate# into the bloodstream. =alling levels ofthyroxin stimulate receptors in the brain to signal the hypothalamus to release a hormonethat acts on the pituitary gland to release thyroid-stimulating hormone "%'2# into the blood.%'2 acts on the thyroid, causing it to increase production of thyroxin.

)ntrinsic

ocal, or intrinsic, controls usually involve only one organ or tissue. hen muscles use moreoxygen, and also produce more carbon dioxide, intrinsic controls cause dilation of the bloodvessels allowing more blood into those active areas of the muscles. *ventually the vesselswill return to HnormalH.

F * #%/ S+!" m! $' Hom o!"#!$!

*;$%)9* =**0B$1F (*12$ )'(

%hese are used by most of the bodyIs systems, and are called negative because the informationcaused by the feedback causes a reverse of the response. egative feedback mechanismconsists of reducing the output or activity of any organ or system back to its normal range offunctioning.

$ good example of this is regulating blood pressure . Blood vessels can sense resistance ofblood flow against the walls when blood pressure increases. %he blood vessels act as thereceptors and they relay this message to the brain . %he brain then sends a message to the

heart and blood vessels, both of which are the effectors. %he heart rate would decrease as theblood vessels increase in diameter "or vasodilation #. %his change would cause the bloodpressure to fall back to its normal range. %he opposite would happen when blood pressuredecreases, and would cause vasoconstriction .%'2 is an example& blood levels of %'2 serve asfeedback for production of %'2.

8O')%)9* =**0B$1F (*12$ )'(

)t is designed to accelerate or enhance the output created by a stimulus that has already beenactivated. )nput increases or accelerates the response. 0uring uterine contractions, oxytocin isproduced. Oxytocin causes an increase in frequency and strength of uterine contractions. %his
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossE.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossN.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossS.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossM.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossT.htmlhttp://en.wikipedia.org/wiki/Blood_pressurehttp://en.wikipedia.org/wiki/Blood_vesselhttp://en.wikipedia.org/wiki/Blood_vesselhttp://en.wikipedia.org/wiki/Brainhttp://en.wikipedia.org/wiki/Hearthttp://en.wikipedia.org/wiki/Diameterhttp://en.wikipedia.org/wiki/Vasodilationhttp://en.wikipedia.org/wiki/Vasoconstrictionhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossO.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossE.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossN.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossS.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossM.htmlhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossT.htmlhttp://en.wikipedia.org/wiki/Blood_pressurehttp://en.wikipedia.org/wiki/Blood_vesselhttp://en.wikipedia.org/wiki/Brainhttp://en.wikipedia.org/wiki/Hearthttp://en.wikipedia.org/wiki/Diameterhttp://en.wikipedia.org/wiki/Vasodilationhttp://en.wikipedia.org/wiki/Vasoconstrictionhttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookglossO.html


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in turn causes further production of oxytocin, etc. /nlike negative feedback mechanisms thatinitiate to maintain or regulate physiological functions within a set and narrow range, the positivefeedback mechanisms are designed to push levels out of normal ranges

%hus, homeostasis depends on the action and interaction of a number of body systems tomaintain a range of conditions within which the body can best operate. 2omeostaticmechanisms are a fundamental characteristic of living things. ithout these mechanisms, facets

of a body that need to be kept operating in a steady state, such as temperature, salinity, acidity,hormone levels, concentration of gases such as carbon dioxide, and the concentrations ofnutrients, would become so unbalanced as to threaten the life of the organism.

STRESS

'tress is a internal state that can be caused by physical demands on body "diseaseconditions, exercise, extremes of temperature etc.# or by the environmental and socialsituations which are evaluated as potentially harmful , uncontrollable or exceeding ourresources for coping.

%he physical, social and environmental causes of stress state are termed as stressors. One

induced by stressors, internal stress state can lead to various physical bodily responses andpsychological responses like depression, anxiety or hopelessness.

S" !!o !

$ little stress is helpful in coping and to adCust but beyond the limit it becomes ! distress.(ain stressors causing distress are&-

8hysical stressors such as inCury , infections , exercise, noise and climatic changes

'ocial stressors are family, social activities , health and financial conditions

8sychological stressors includes frustration, conflicts etc.

GENERAL ADAPTATION SYNDROME

Bodys response to stressors is called Egeneral adaptation syndromeG. )t consists of threestages&-

$larm reaction

'tage of resistance

'tage of exhaustion

01 ALARM REACTION

)t is essentially the emergency response of body. )n this stage, prompt responses of the body,many of them mediated by the sympathetic nervous system, preparing the body to cope withstressors.

21 STAGE OF RESISTANCE


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)f stressor continues to be present, stage of resistance begins, where body resists the effect ofcontinuous stressors Jstimuli.

0uring this stage, certain hormonal responses of the body are important line of defense inresisting the effects of stressors or stimuli.

(ainly $1%2 "adrenocorticotrophic hormone# is important and more active among hormonalresponse.

'ecretion of $1%2 is controlled by 1 = "corticotrophin releasing factor#, made by cellsof brainstructure "hypothalamus#.

'tressorsJstimuli stimulate hypothalamus to release more 1 =, in turn increasing the secretionof $1%2 from pituitary glands.

$1%2 stimulates adrenal gland to secrete steroid hormones such as cortisol into the blood.

1ortisols adaptively deal with stressors or stimuli for long period of time but maintenance forlong period of time may be harmful.

8rolonged elevation of cortisol levels results in elevated blood pressure and other hormones inexcess may have their owns harmful actions which may worsen the bodys response tostimulus.

31 STAGE OF EXHAUSTION

=inal stage of general adaptation syndrome is the stage of exhaustion. )n this stage, the bodyscapacity to respond to both continuous and new stressorsJstimuli is seriously compromised. =oreg& - due to actions of cortisol, person may not be longer able to ward off infection and becomessick and die.

SOURCES OF STRESS

%here are many sources of stress. %hey are broadly classified a

I'" '# !" !!o ! , which arise from within the body like infection, feelings ofdepression.

E4" '# !" !!o ! originate outside of individual like transfer to another city, ordeath in family or any pressure from peer.

D 5 o.m '"# !" !!o ! occur at predictable times throughout individuals life.

S$"6#"$o'# !" !!o ! are unpredictable and may occur at any time. *xamplesare&

0eath of family member

(arriage or divorce

Birth of child

ew Cob


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)llness.

E %"! o !" !!

'tresses have physical, emotional, intellectual, social and spiritual consequences./sually effects are mixed as stress affects whole of the body.

8hysically, stress can threaten persons physiologic homeostasis.

*motionally, it can produce negative or self-destructive feelings about self.

)ntellectually, stress can influence persons problem solving abilities andperceptual abilities.

'piritually, stress can challenge ones beliefs and values.

MANIFESTATIONS

8upils dilate to increase visual perception when serious threats to body arise.

0iaphoresis increases to control elevated heat due to increase metabolism.

2eart rate and cardiac output increases to transport nutrients and by productseffectively

8allor skin due to vasoconstriction of blood vessels due to effect of norepinephrine.

'odium and water retention increases due to release of mineral corticoids , whichincreases blood volume,

espiratory rate increases in rate and depth due to vasodilation causinghyperventilation.

/rine output decreases.

0ry mouth

0ecreased peristaltic movements

(ental alertness improves.

)ncreased muscle tension.

Blood sugar increases dye to release of glucocorticoids and gluconeogenesis.

COPING 7ITH STRESS

1oping may be described as dealing with change-successfully or unsuccessfully. 1opingstrategies is a natural or learned way of responding to a changing environment or specificproblems or situation. Or coping is cognitive and behavioral effort to manage specific external


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andJor internal demands that are appraised as exceeding or taxing the resources of the person.1oping strategies can be long term and short term.

ong term coping strategies can be constructive and realistic. =or example, in anysituation talking with others or trying to find out more about situation.

Others include changes in lifestyle pattern such as eating a healthy diet, exercising

regularly, using problem solving in decision making instead of anger etc. 'hort term strategies can reduce stress to a tolerable limit temporarily but are ineffective

ways to permanently deal with reality. %hey may have destructive effects on the person.

*xamples are using alcoholic beverages or drugs, daydreaming, etc.

1oping mechanisms can be adaptive or maladaptive.

$daptive coping help the person to deal effectively with stressful events and minimi:esdistress associated with them.

(aladaptive coping can result in unnecessary distress for person

NURSING MANAGEMENT

urse needs to remember that coping is always purposeful. %he effectiveness of personscoping is influenced by number of factors. )ncluding,

umber ,duration and intensity of stressors

8ast experiences of individual

8ersonal qualities of individual.

'upport systems available to individual.

3. ASSESSMENT &- assessment includes

ursing history &- it includes questions related to client perceived stressors orstressful events , past and present strategies and signs of stress.

8hysical examination for indicators of stress like nail biting , nervousness ,weightchanges or stress related problems like hypertension , dyspnea.

5. DIAGNOSIS &- it includes $nxiety due to stressors

1ompromised family coping

=ear related to perceived threat

)mpaired adCustment to situation

)neffective coping


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8ost trauma syndrome

>. PLANNING &-nurse must develops plans in collaboration with patient and significantsupport people according to clients health state , level of anxiety, support resources,coping mechanisms.

?. IMPLEMENTATION: - nurse can choose one of these methods of intervention that willbe effective for client .

2ealth promotion strategies &- it includes&-

*xercise helps to relieve tensions , promotes a feeling of well being andrelaxation

Optimal utrition helps in increasing the bodys resistance to stress. 8eopleneed to avoid excess of caffeine , salt, sugar and fat and deficiencies in vitamins andminerals .

'leep helps in restoring the bodys energy levels and managing stress.

%ime management helps in less stress situations.

(inimi:ing anxiety &- nurses must carry out measures to minimi:e anxiety andstress of patient for example , encourage the patient to take deep breaths beforegiving inCections or massaging the client to relax.

/sing relaxation techniques & - several relaxation techniques are used to relax themind and tension . urse should encourage the clients to use these techniques instressful situations like during child birth, before and during painful procedures orpostoperatively to cope with pain. %hese techniques includes&-

Breathing exercises

(assage

8rogressive relaxation

7oga

(editation

(usic therapy

2umor and laughter therapy.

%hese are the various strategies which can be used to deal with stress and person willbe able to prevent and minimi:e the effects of stressors on the body.

SLEEP

e have to sleep because it is needed to sustaining normal levels of cognitive skills such asspeech, memory, and innovative and flexible thinking. )n other words, sleep plays an importantpart in brain development 1


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$ behavior characteri:ed by a change in consciousness and marked by a set of particularbehaviors.

Brain and body rest

Brain engages in several activities

Brain (echanisms 1ontrolling 'leep

'leep is promoted by a complex set of neural and chemical mechanisms

0aily rhythm of sleep and arousal

suprachiasmatic nucleus of the hypothalamus

pineal glands secretion of melatonin

'low-wave sleep

nuclei of the medulla and pons and the secretion of serotonin

*( sleep

neurons of the pons

STAGES OF SLEEP

'leep occurs in a recurring cycle of K4 to 334 minutes and is divided into two categories& non-*( "which is further split into four stages# and *( sleep. %here are four stages in the non-*( sleep. *( stands for rapid eye movement.

on- *( sleep

0uring the first stage of sleep, weIre half awake and half asleep. Our muscle activity

slows down and slight twitching may occur. %his is a period of light sleep, meaning wecan be awakened easily at this stage.

ithin ten minutes of light sleep, we enter stage two, which lasts around 54 minutes.%he breathing pattern and heart rate start to slow down. %his period accounts for thelargest part of human sleep.

0uring stage three, the brain begins to produce delta waves, a type of wave that is large"high amplitude# and slow "low frequency#. Breathing and heart rate are at their lowestlevels.

'tage four is characteri:ed by rhythmic breathing and limited muscle activity. )f we areawakened during deep sleep we do not adCust immediately and often feel groggy anddisoriented for several minutes after waking up. 'ome children experience bed-wetting, nightterrors, or sleepwalking during this stage.

*( 'leep


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%he first apid *ye (ovement " *(# period usually begins about 64 to K4 minutes afterwe fall asleep. e have around three to five *( occurrences a night.

$lthough we are not conscious, the brain is very active - often more so than when weare awake. %his is the period when most dreams occur. Our eyes dart around, and ourbreathing rate and blood pressure rise. 2owever, our bodies are effectively paraly:ed,which is said to be natureIs way of preventing us from acting out our dreams.

$fter *( sleep, the whole cycle begins again.

EFFECTS OF SLEEP DEPRIVATION

'leep deprivation not only has a maCor impact on cognitive functioning but also onemotional and physical health. 0isorders such as sleep apnea, a temporary suspensionof breathing, occurring in some newborns "infant apnea# and in some adults duringsleep, which result in excessive daytime sleepiness that have been linked to stress andhigh blood pressure. esearch has also suggested that sleep loss may increase the riskof obesity because chemicals and hormones that play a key role in controlling appetiteand weight gain are released during sleep.

$fter Cust one night without sleep, concentration becomes more difficult and attentionspan shortens a great deal.

ith continued lack of sufficient sleep, the part of the brain that controls language,memory, planning and sense of time is severely affected, practically shutting down.

SLEEPING DISORDERS

'omnambulism sleepwalking

ightmares - frightening dreams that wake a sleeper from *(

ight terrors - sudden arousal from sleep and intense fear accompanied by physiologicalreactions "e.g., rapid heart rate, perspiration# that occur during slow-wave sleep

arcolepsy - overpowering urge to fall asleep that may occur while talking or standing up

'leep apnea - failure to breathe when asleep

B)B )O; $827

Fosskyn (.stephan. osenberg'. obin.8sychology in context.> rd edition. ew 0elhi&0orling Findersley ")ndia# pvt.ltdL 544M.8p-@MM-@K3.

ade 1arole, tavris carol .psychology.edtion M th . ew 0elhi& 0orling Findersley ")ndia#

pvt.ltdL 544M.8p-@>M-@?@.

(organ %.clifford, king $. ichyard, 'chopler Dohn, eis: . Cohn. )ntroduction topsychology. *dition 6 th. ew 0elhi & %ata (c;raw-hill publishing company ltdL 3KK>.8p->54->>4.

www.bbc.co.ukJscienceJhumanbodyJsleepJarticlesJwhatissleep.shtml

http&JJfaculty.washington.eduJchudlerJsleep.html

images.google.com
http://www.bbc.co.uk/science/humanbody/sleep/articles/whatissleep.shtmlhttp://www.bbc.co.uk/science/humanbody/sleep/articles/whatissleep.shtmlhttp://faculty.washington.edu/chudler/sleep.htmlhttp://faculty.washington.edu/chudler/sleep.htmlhttp://var/www/apps/conversion/tmp/scratch_6/images.google.comhttp://www.bbc.co.uk/science/humanbody/sleep/articles/whatissleep.shtmlhttp://faculty.washington.edu/chudler/sleep.htmlhttp://var/www/apps/conversion/tmp/scratch_6/images.google.com


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http&JJen.wikipedia.orgJwikiJ2omeostasis

www.lifepositive.com/Mind/psychology/ stress / stress

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Human Behaviour (2)