Consciousness
Body Rhythms
Pages 156-160
Consciousness:Body rhythms and mental states
chapter 5
Objectives: The student will
•Analyze body rhythms, including circadianrhythms
•Describe when the body is out of synch (thebody clock)
•Summarize P.M.S.
Objective #1
•Consciousness- the process underlying themental model we create of the world whichwe are aware
•Biological rhythms- Biological clock in ourbrains= governs hormone level, bloodpressure, responsiveness of brain cells tostimuli
•Most B.R.’S= Endogenous, generated fromwithin.
Understanding biologicalrhythms
Consciousness
Awareness of oneself and theenvironment
Biological rhythms
A periodic, more or less regularfluctuation in a biological system; mayor may not have psychologicalimplications
chapter 5
Objective #1
•Circadian Rhythms- bodily patterns that occurevery 24 hours, most common sleep-wake
•However 100’s more, alertness, tasks
•Circa (about) + dies (day)= 24 hour day
•Work schedules, time change, staying up all nightto study, all effect cycle
•Influenced by external cues
•Participants in studies Awake 20-25 hours, sleepfor 10.
Circadian Rhythms
Endogenous biologicalrhythms
Circadian rhythms
Once about every 24 hours
Example: the sleep-wake cycle
chapter 5
Circadian rhythms
Occur in animals, plants, andpeople
To study endogenous circadianrhythms, scientists isolatevolunteers from time cues.
Suprachiasmatic nucleus
Located in hypothalamus, regulates melatonin,a hormone secreted by the pineal gland
chapter 5
Body’s Clock
•C.R.’S controlled by biological clock= super clusterof cells in hypothalamus called Suprachiasmatic (soo-pruh-kie-as-MAT-ick) nucleus (SCN)
•Sends messages up neural pathways; responds tolight and dark
•SCN regulates hormones and neurotransmitters
•Melatonin, Pinal gland- Responds to light anddark
•Darkened room-=melatonin rises O.T.O.H.lightened room=falls
SCN
When the clock is out of synch
•Internal desynchronization- a STATE IN WHICHBiological rhythms are not in phase(synchronized) with one another
•Jet lag, body temp., hormone levels adjusted
• new shift at work could be disaster; ExxonValdez, 3 mile island
Internaldesynchronization
A state when biological rhythmsare not in phase with each other
Circadian rhythms are influencedby changes in routine.
Airplane flights across time zones
Adjusting to new work shifts
Illness, stress, fatigue, excitement,drugs, and mealtimes
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Internal des.
Moods and long term rhythms
•Birds migrate south, bears hibernate, seacreatures become inactive so effected byseasons
•Seasonal affective disorder ( SAD)- Peoplebecome depressed when there is less sunlight
•Studies show lifetime of major seasonaldepression 0.4%
Moods and long-termrhythms
Seasonal Affective Disorder (SAD)
A controversial disorder in which a personexperiences depression during the Winter andan improvement of mood in the Spring.
Treatment involves phototherapy or exposureto fluorescent light.
Evaluating frequency of and treatment for SADis difficult.
chapter 5
SAD
Menstrual Cycle affect moods
•1st half of cycle more estrogen lines uterus forpossible baby
•Mid cycle release the egg, produceprogesterone
•Then if conception does not occur, E. & P. fall
•So does physical changes correlate toemotional or intellectual changes?
P.M.S.
•1970’s vague cluster of physical and emotionalproblems days before menstruation
•Fatigue, irritability, headache, depression
•Premenstrual syndrome- 13% to “mostwomen”
•Physical symptoms, cramps, breast tenderness
•However just like sad many more people thinkthey have symptoms than actually do
Menstrual cycles andmood
Physical symptoms are common
Cramps, breast tenderness, and waterretention
Emotional symptoms are rare
Irritability and depression
Fewer than 5% of women have symptomspredictably.
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Why women overestimate“PMS”
They notice depression or irritabilitywhen these moods occur premenstruallybut overlook times when moods areabsent premenstrually.
They attribute irritability beforemenstruation to PMS and irritability atother times to other causes.
They are influenced by cultural attitudesand myths about menstruation.
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Research conclusionsabout “PMS”
No gender differences inmood
No relation betweenstage of menstrual cycleand emotionalsymptoms
No consistent “PMS”pattern acrossmenstrual cycles
No connection between“PMS” and behavior
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Summaries
•Circadian rhythms
•Body clock
•P.M.S.