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What |is |the |nervous |system |- |...,. VERIFIED |ANSWER |✔✔The |nervous |system |is |a |specialised |group |of |cells |in |our |body |and |is |our |primary |communication |system, |it |collects |processes |and |responds |to |different |information |and |co-ordinates |the |working |of |different |functions |within |the |body. |It |is |made |up |of |both |the |central |nervous |system |and |the |peripheral |nervous |system. What |is |the |central |nervous |system |(CNS) |- |...,. VERIFIED |ANSWER |✔✔The |CNS |includes |the |brain |and |the |spinal |cord, |the |brain |is |the |centre |of |all |conscious |awareness |and |it |is |the |outer |layer, |the |cerebral |cortex, |which |distinguishes |us |from |animals. |The |spinal |cord |is |an |extension |o |the |brain |and |is |responsible |for |our |reflexes |and |movements. The |spinal |cords |main |function |is |to |relay |information |from |the |brain |to |the |rest |of |the |body. | The |brain |is |made |up |of |four |main |areas, |the |brain |stem, |the |diencephalon, |the |cerebellum |and |the |cerebral |cortex. The |brain |stem |regulates |automatic |functions |such |as |breathing |and |swallowing. The |diencephalon |comprises |the |thalamus |which |takes |nerve |impulses |from |the |senses |to |the |brain |and |the |hypothalamus |that |regulates |body |temp |and |hunger. The |cerebellum |that |controls |motor |skills |and |balance |co-ordinating |muscles |to |work |together. The |cerebral |cortex |is |divided |into |four |lobes |each |with |a |different |function: POFT The |Parietal |lobe |for |sensory |information The |Occipital |lobe |for |the |processing |of |visual |information The |Frontal |lobe |for |thought |and |speech The |Temporal |lobe |for |auditory |information |and |memory
What |is |the |peripheral |nervous |system |(PNS) |- |...,. VERIFIED |ANSWER |✔✔The |PNS |is |divided |into |two |main |sections |the |first |being |the |somatic |nervous |system. This |is |made |up |of | 12 |pairs |of |cranial |nerves |and | 31 |pairs |of |spinal |nerves, |containing |both |sensory |and |motor |neurons |it |is |also |involved |in |reflex |actions. | The |autonomic |nervous |system |is |much |more |complex, |it |essentially |regulates |involuntary |actions |such |as |heart |rate |without |any |conscious |awareness. |It |is |made |up |of |the |sympathetic |nervous |system |and |the |parasympathetic |nervous |system |which |have |opposing |effects |on |the |body. The |sympathetic |nervous |system |helps |us |deal |with |emergencies |(fight |or |flight), |it |increases |the |heart |rate, |blood |pressure |and |dilates |pupils. |It |can |also |shut |down |non |essentials |like |digestion. | The |parasympathetic |nervous |system |has |the |opposite |effect |of |the |fight |or |flight, |as |this |response |triggers |homeostasis. |This |relaxes |the |individual |after |the |emergency, |slowing |heart |rate |and |non |essentials |back |on. What |are |neurons |and |outline |the |three |main |ones |- |...,. VERIFIED |ANSWER |✔✔Neurons |are |specialised |cells |designed |for |the |transmission |of |information |throughout |the |body, |there |are |three |types: Sensory |neurons, |these |carry |impulses |from |receptors |to |the |spinal |cord/brain. Relay |neurons |allow |sensory |and |motor |neurons |to |communicate |with |each |other, |located |in |the |brain |and |spinal |cord. Motor |neurons |from |synapses |with |muscles |and |when |an |impulse |travels |down |the |motor |neuron |it |causes |the |muscle |to |contract. Outline |synaptic |transmission |- |...,. VERIFIED |ANSWER |**✔✔Action |potential |is |the |electrical |signal |that |travels |down |the |neuron |to |the |axon |ready |to |be |passed |on. To |cross |a |synaptic |junction |the |end |of |an |axon |has |many |sacks |of |neurotransmitters |known |as |vesicles |which |assist |the |message |transfer. |When |the |action |potential |reaches |the |synaptic |vessels |it |causes |them |to |release |neurotransmitters, |this |is |known |as |exocytosis. The |neurotransmitter |diffuses |across |the |synaptic |junction |and |binds |to |receptor |sites |on |the |post |synaptic |knob. |Once |these |sites |are |activated |it |produces |either |an |excitatory |or |an |inhibitory |effect |on |the |post |synaptic |knob.
It |works |by |as |follows, |when |faced |with |a |stressful |situation |the |amygdala |is |activated |a |signal |is |then |sent |to |the |hypothalamus |which |uses |the |sympathetic |nervous |system |to |communicate |with |the |rest |of |the |body. It's |response |to |acute |stress |takes |the |sympathomedullary |pathway |(SAM). |When |the |SNS |is |triggered |it |sends |a |signal |to |the |adrenal |medulla |which |releases |adrenaline |into |the |blood. |The |adrenaline |causes |the |heart |to |beat |faster |allowing |for |more |blood |into |the |brain. |After |a |while |the |parasympathetic |nervous |system |is |triggered |causing |the |stress |response |to |be |dampened |down. After | 20 |minutes |if |the |stress |is |continued, |it |is |then |known |as |chronic |stress |and |the |response |is |different. |Instead |of |the |sympathomedullary |pathway |it |takes |the |hypothalamic |pituitary |adrenal |system |(HPA). The |hypothalamus |releases |the |chemical |corticotrophin |releasing |hormone |into |the |blood |stream, |this |arrives |at |the |pituitary |gland |causing |it |to |release |adrenocorticotrophic |hormone. |This |is |then |targeted |at |the |adrenal |gland, |specifically |the |adrenal |cortex, |causing |the |release |of |cortisol |which |gives |a |quick |burst |of |energy |and |higher |pain |thresholds. |However |it |can |lower |both |the |immune |system |and |impair |cognitive |performance. Evaluate |the |fight |or |flight |response |- |...,. VERIFIED |ANSWER |**✔✔:( |- |Research |suggests |that |females |have |a |different |behavioural |response |to |stress, |known |as |tend |and |befriend. |This |is |due |to |women's |role |as |a |PCG, |they |are |thus |more |likely |to |protect |themselves |and |their |children |through |nurturing |behaviours |and |forming |alliances |with |other |women. |This |suggests |that |therefore |women |may |have |evolved |differently |saying |that |the |fight |or |flight |response |can |not |be |applied |to |both |genders. :( |- |The |flight |part |of |fight |or |flight |could |be |detrimental |to |the |safety |of |women's |offspring. |Research |conducted |with |rats |found |that |women |may |release |oxytocin |which |inhibits |flight. |This |hormone |has |been |shown |to |increase |relaxation. |This |research |further |shows |evidence |for |the |fight |or |flight |not |being |able |to |be |applied |to |women. :( |- |The |fight |or |flight |response |is |an |evolutionary |survival |technique |however |modern |day |life |can |trigger |this |too |frequently |in |inappropriate |situations. |This |can |be |detrimental |to |out |health |and |cause |coronary |heart |disease. |Furthermore |too |much |cortisol |can |result |in |us |being |more |prone |to |illness. |Therefore |the |very |process |that |is |designed |to |save |our |lives |could |in |fact |cause |illness.
:( |- |Research |suggests |that |there |are |other |responses |before |fight |or |flight. |He |said |that |humans |are |more |interested |in |avoiding |confrontation |rather |than |fleeing |it. |This |is |known |as |the |freeze |response |where |by |people |are |hyper |vigilant |and |alert |to |any |danger. |The |freezing |focuses |attention |and |helps |people |find |new |information |in |order |to |deal |with |the |threat. |This |limits |the |value |of |insight |psychologists |have |in |accurately |explaining |response |to |stress. Outline |the |localisation |of |the |brain |- |...,. VERIFIED |ANSWER |✔✔The |motor |cortex |is |responsible |for |all |voluntary |movements |and |is |located |within |the |frontal |lobe |in |the |precentral |gyrus. |Both |hemispheres |have |a |motor |cortex |with |each |side |controlling |opposing |sides |of |the |body. |Different |parts |of |the |motor |cortex |control |different |parts |of |the |body. The |somatosensory |cortex |detects |sensory |information |from |all |over |the |body, |it |is |located |within |the |parietal |lobe |in |the |postcentral |gyrus. | The |visual |centre |is |located |within |the |visual |cortes |inside |the |occipital |lobe. |nerve |impulses |from |the |retina |travel |along |the |optic |nerve |to |the |thalamus, |passing |on |this |information |to |the |visual |cortex. Auditory |cortex |is |concerned |with |hearing, |it |lies |within |the |temporal |lobes |in |each |hemisphere |of |the |brain. |The |pathway |begins |in |the |cochlea |within |the |ear |where |sound |waves |are |converted |to |impulses |that |travel |down |the |auditory |nerve |to |the |auditory |cortex. | There |are |two |language |centres, |the |first |is |responsible |for |speech |production |and |is |known |as |the |Broca's |area, |it |is |said |that |this |is |in |the |posterior |portion |of |the |frontal |lobe |in |the |left |hemisphere. |The |other |is |responsible |for |speech |understanding |and |is |called |Wernicke's |area, |it |lays |within |the |posterior |portion |of |the |left |temporal |lobe. Evaluate |the |localisation |of |the |brain |- |...,. VERIFIED |ANSWER |✔✔:) |- |There |is |evidence |that |supports |the |localisation |of |function |of |language. |Patients |with |damage |to |the |areas |where |language |centres |are |experience |aphasia, |this |is |an |inability |to |understand |and |produce |speech. |Specific |damage |to |Broca's |area |demonstrates |the |importance |of |this |region |for |speech |production |and |the |same |with |Wernicke's |area. :( |- |Not |all |researchers |agree |that |the |brain |has |localisation |of |function. |One |researcher |founded |the |equipotential |theory. |It |states |that |basic |motor |and |sensory |functions |are |localised |but |higher |mental |functions |are |not |and |that |if |there |is |a |brain |injury |intact |areas |of |the |rain |will |take |over |for |specific |functions. |
Evaluate |the |lateralisation |of |the |brain |- |...,. VERIFIED |ANSWER |✔✔:( |- |The |advantage |of |having |hemispheric |lateralisation |is |that |it |increases |neural |processing |capacity. |This |is |due |to |the |fact |that |if |we |use |just |the |left |side |for |language |then |the |right |side |would |be |free |to |do |another |task |at |the |same |time. |However |there |is |very |little |evidence |to |show |that |this |happens. | :( |- |Lateralisation |may |be |beneficial |in |some |circumstances |for |example |some |people |who |are |mathematically |gifted |will |have |superior |right |hemispheric |skills |however |these |people |are |also |more |likely |to |suffer |from |higher |rates |of |allergies |and |general |problems |with |their |immune |systems :( |- |Lateralisation |can |change |with |age, |research |has |shown |that |initial |lateralised |patterns |in |young |people |can |change |into |bi-lateral |patterns |in |healthy |older |adults. |Specifically |language |became |more |lateralised |to |the |left |hemisphere |in |children |but |by |the |age |of | 25 |lateralisation |decreased |with |every |year. :( |- |The |sample |sizes |in |the |original |studies |were |often |as |small |as |three |participants |and |also |many |had |confounding |variables |before |they |became |split |brain |and |thus |we |must |be |cautious |when |generalising |the |findings |to |the |whole |population Outline |brain |plasticity |- |...,. VERIFIED |ANSWER |✔✔Brain |plasticity |refers |to |the |ability |of |the |brain |to |change |and |adapt |as |a |result |of |experience. It |is |now |believed |that |the |brain |continues |to |create |neural |pathways |all |the |time |and |alter |existing |ones. Life |Experience When |people |gain |new |experiences, |nerve |pathways |that |are |used |frequently |create |stronger |and |more |connections |and |pathways |that |are |rarely |used |become |weaker |and |some |may |break |down |completely. |Although |this |is |seen |as |a |huge |benefit |there |is |however |a |natural |decline |in |cognitive |performance |with |age, |which |may |also |be |due |to |the |the |brains |constant |adaptation. |To |try |and |help |elders |reverse |this |a |researcher |found |that |teaching | 60 |year |olds |to |juggle |increased |grey |matter |in |the |visual |cortex. |However, |when |they |stopped |practising |the |changes |were |again |reversed.
Video |Games A |researcher |found |that |playing |video |games |requires |complex |cognitive |and |motor |demands. |A |group |of |participants |played |Super |Mario |for | 30 |minutes |a |day |for |two |months |and |found |significant |increase |in |grey |matter |in |both |the |cortex |and |hippocampus. Meditation Research |has |shown |that |meditation |can |change |the |inner |workings |of |the |brain. |They |found |that |when |comparing |monks |to |regular |humans |with |no |meditation |experience |that |the |monks |had |much |greater |activity |of |gamma |waves |than |the |students. Outline |functional |recovery |of |the |brain |- |...,. VERIFIED |ANSWER |**✔✔It |seems |that |stroke |victims |are |able |to |regain |functioning |of |the |brain |several |months |after |a |stroke. |It |seems |that |the |brain |can |rewire |itself |so |that |other |parts |can |take |over |from |damaged |areas, |neurons |around |these |areas |form |new |circuits |to |working |areas. Neural |Unmasking Wall |found |dormant |synapses |within |the |brain |which |are |essentially |spare |unused |synapses. |When |the |brain |is |damaged |areas |around |these |dormant |synapses |seem |to |become |very |active |and |thus |unmasking |them. |These |new |connections |create |a |lateral |spread |of |activation |which |over |time |develops |new |structures. | Stem |Cells Stem |cells |are |unspecialised |cells |that |have |the |ability |to |be |used |in |any |part |of |the |body |and |become |specialised. |There |are |three |main |ways |to |use |them:
- |Implanted |into |the |brain |and |replace |dead |cells
- |Transplanted |stem |cells |secrete |growth |hormone |that |rescue |dead |cells
- |Transplanted |stem |cells |form |a |neural |pathway |linking |uninjured |areas |to |injured |areas Evaluate |plasticity |of |the |brain |- |...,. VERIFIED |ANSWER |**✔✔:) |- |Animal |studies |provide |evidence |for |the |brains |ability |to |demonstrate |plasticity |based |on |the |environment. |A |researcher |found |that |rats |who |were |put |in |a |rich |environment |compared |to |those |which
Event-related |Potentials |(ERP) Similar |to |EEG's |however |this |looks |at |the |brain |reacting |to |a |stimulus |instead |of |just |stand |alone. |It |looks |at |very |quick |high |voltage |changes |within |the |brain, |it |is |difficult |to |isolate |the |other |electrical |activity |and |thus |to |remove |background |noise |the |target |stimulus |is |presented |many |times |to |the |patient |and |the |response |is |averaged |out |and |background |noise |removed. |There |are |two |types |of |waves |occurring |after |presentation |of |stimulus: |Sensory |ERP's |before |100ms |and |Cognitive |ERP's |after |100ms |of |stimuli. Post |Mortem |Examinations These |are |used |after |a |patient |has |died |to |physically |see |the |neurobiology |of |a |particular |behaviour. |For |example |Broca's |work |analysing |the |brains |of |people |who |had |speech |problems |led |him |to |discover |the |important |area |responsible |for |speech. Evaluate |each |way |of |studying |the |brain |- |...,. VERIFIED |ANSWER |**✔✔FMRI :) |- |Non |invasive |and |does |not |expose |brain |to |potentially |harmful |radiation |as |is |the |case |with |other |scan |methods :) |- |Offers |a |more |objective |and |reliable |measure |of |psychological |processes |than |is |possible |with |verbal |reports. |It |is |a |useful |way |of |investigating |psychological |behaviour |using |a |quantitative |report :( |- |A |FMRI |measures |changes |in |ion |level |rather |than |directly |measuring |brain |activity |it |is |not |then |a |direct |measure |of |neural |activity. |This |means |it |is |not |a |truly |quantitative |measure |of |mental |activity |in |these |brain |areas :( |- |People |argue |that |FMRI |overlooks |the |networked |nature |of |the |brain |and |rather |just |looks |at |the |localised |activity. |It |is |communication |within |the |brain |that |is |key, |not |just |each |area |working |separately EEG
:) |- |An |advantage |of |the |EEG |technique |is |that |it |provides |a |constant |recording |of |the |brains |activity |rather |than |just |a |still |image. |This |means |the |researcher |can |more |accurately |measure |brain |activity |in |a |particular |task :) |- |EEG's |are |good |for |clinical |diagnosis |for |example |epilepsy |can |be |diagnosed |easily |as |when |someone |is |experiencing |a |seizure |the |EEG |reading |should |suddenly |change :( |- |EEG's |can |only |see |what |is |going |on |in |superficial |areas |of |the |brain |and |not |the |deeper |regions |and |thus |it |cant |see |important |areas |such |as |the |hippocampus :( |- |Although |there |are |many |seperate |electrodes |as |part |of |an |EEG |a |lot |of |the |time |a |group |of |electrodes |will |detect |the |spike |in |voltage |change |and |thus |it |is |hard |to |say |exactly |where |the |change |originates |from ERP :) |- |As |ERP's |provide |a |continuous |measure |of |brain |activity |in |response |to |a |stimuli |it |makes |it |possible |to |determine |exactly |how |a |stimulus |affects |the |brain |and |thus |drawing |a |cause |and |effect |relationship :) |- |An |ERP |can |measure |the |reaction |to |stimuli |without |the |need |for |the |patient |to |lear Outline |the |three |biorhythms |- |...,. VERIFIED |ANSWER |**✔✔Biorhythms |are |biological |processes |that |show |cyclical |variation |over |time |and |reflect |the |influence |of |earths |rotation |on |animals Circadian These |follow |day |and |night |and |are | 24 |hours, |the |ones |psychologists |are |most |interested |in |is |the |sleep |wake |cycle Ultradian
:( |- |An |important |criticism |is |th Outline |and |evaluate |infradian |and |ultradian |rhythms |- |...,. VERIFIED |ANSWER |✔✔Ultradian |rhythms |span |for |less |than |a |day, |an |example |would |be |the |five |stages |of |sleep |which |lasts |for |around | 90 |mins |before |it |repeats |itself. The |first |two |stages |are |light |sleep |with |the |brain |producing |beta |and |alpha |waves |and |eventually |theta |when |you |start |to |fall |deeper |into |sleep. |The |third |and |fourth |stages |consist |of |mainly |delta |waves |resulting |in |the |person |being |very |difficult |to |wake |up |but |still |conscious, |in |this |sleep |is |where |its |thought |growth |hormone |is |released |to |repair |the |body. |The |final |stage, |stage | 5 |is |REM |sleep |with |EEG |activity |resembling |that |of |an |awake |brain. :) |- |Research |suggests |that |in |REM |sleep |people |dream. |Researchers |woke |up |participants |during |the |night |when |their |brain |activity |was |characteristic |of |REM |sleep. |They |found |that |participants |were |highly |likely |to |be |dreaming |at |this |time, |with |some |having |matching |eye |movements |in |sync |with |the |dream :( |- |However |these |findings |were |not |absolute |as |there |was |found |to |be |widespread |individual |differences |because |some |dreams |were |recorded |outside |REM |sleep |and |some |dreaming |just |didn't |occur |in |REM |sleep. |This |suggests |that |other |factors |may |have |affected |their |dreaming |so |it |suggests |more |research |is |needed |on |topic |before |firm |conclusions |are |drawn. Infradian |rhythms |span |over |times |longer |than |a |day |but |less |than |a |year, |on |example |would |be |the |menstrual |cycle |whereby |ones |a |month |females |pituitary |gland |will |release |hormones |which |cause |a |follicle |to |ripen |an |egg. |When |the |egg |is |ready |progesterone |is |released |to |help |the |womb |before |pregnancy. |After |two |weeks |if |there |is |no |fertilisation |progesterone |levels |decrease |and |the |womb |is |shed. Another |infradian |rhythm |is |seasonal |affective |disorder, |which |is |a |depressive |condition |during |the |winter |months |that |is |due |to |fewer |hours |of |sunlight. |It |is |thought |that |more |darkness |i Outline |endogenous |pacemakers |and |exogenous |zeitgebers |- |...,. VERIFIED |ANSWER |✔✔One |of |the |most |important |endogenous |pacemakers |is |the |suprachiasmatic |nucleus |which |is |a |tiny |cluster |of |nerve |cells |located |in |the |hypothalamus, |connected |to |the |eye. |This |acts |as |the |master |clock |linking |other |brain |regions |that |control |sleep |and |arousal. |Neurons
|within |the |SCN |sync |with |each |other |so |that |target |neurons |elsewhere |int |he |body |receive |timed |signals. In |the |morning |light |penetrates |the |eyelid |to |the |retina |which |stimulates |the |SCN |to |cause |the |pineal |gland |to |regulate |the |amount |of |melatonin |being |produced. |Thus |the |more |light |the |less |of |this |chemical |and |the |more |awake |someone |will |feel. Light |is |the |most |dominant |exogenous |zeitgeber |in |humans, |with |the |ability |to |entrain |and |reset |internal |clocks. |It |also |has |the |power |to |entrain |other |oscillators, |as |a |ket |ingredient |of |the |protein |clock, |crypto-chrome |is |light |sensitive. |The |eye |contains |special |light |detecting |cells |called |melanopsin |which |are |responsible |for |carrying |signals |to |the |SCN |to |help |set |the |bodies |daily |cycle. As |well |as |light, |other |social |cues |also |play |a |role |in |our |circadian |rhythms, |meal |times |for |example |act |as |an |exogenous |zeitgeber |as |the |cells |in |the |liver |are |likely |to |be |reset |by |eating. | Aschoff |found |that |jet |lag |could |be |reduced |if |we |spent |more |time |outside |at |their |destination |traveled |to, |and |not |this |being |due |to |the |light |but |rather |the |social |cues |around |you |allowing |your |body |to |adjust |quicker Evaluate |endogenous |pacemakers |and |exogenous |zeitgebers |- |...,. VERIFIED |ANSWER |**✔✔:) |- |Burgess |found |that |bright |light |exposure |before |an |east |west |flight |can |help |minimize |jet |lag. |Participants |rhythms |were |shifted |back |by | 2 |hours |per |day |for |three |days. |Other |research |suggests |the |spectral |composition |of |light |is |very |important |and |that |exposure |to |warm |light |over | 5 |weeks |was |much |more |effective |then |blue |light. |This |confirms |light |as |an |external |zeitgeber :( |- |Evidence |for |the |SCN |was |found |when |conducting |an |experiment |on |hamsters. |Psychologists |removed |the |SCN |and |found |that |their |usual |circadian |rhythm |disappeared |and |when |it |was |put |back |it |was |re-established. |However |critics |are |quick |to |point |that |a |weakness |of |this |research |is |that |it |was |done |on |animals |that |are |quantitatively |different |to |humans |and |thus |must |be |very |cautious |when |extrapolating |the |findings |this |therefore |means |the |research |can |be |criticized |for |anthropomorphism :( |- |It |is |more |appropriate |to |suggest |that |circadian |rhythms |are |multi |dimensional |in |the |sense |that |it |can |be |influenced |by |both |endogenous |and |exogenous |factors. |To |think |of |it |as |a
