1. Biology, Sensation/Perception, and Consciousness
Domain Two
Biology, Sensation/Perception, and Consciousness

2. Biology

3. The Nervous System Two main parts
Central Nervous System: the brain and the spinal cord

4. The Nervous System Two main parts
Peripheral Nervous System: contains nerve cells; has two divisions
Somatic Nervous System: activated by touch, pain, and temp
Automatic Nervous System: regulates the body’s vital functions (like our heartbeat)

5. The Brain

6. Parts of the Brain
There are some sections listed on our Zombie article!
Pons: help regulate sleep
Limbic System: involved in learning, memory, emotion, hunger, sex, and aggression
Cerebrum/Cerebral Cortex: the part that does the thinking

7. The Two Halves Connected by the corpus callosum
Information received by one side of the body is transmitted to the opposite hemisphere of the brain
Don’t act independently, but some think…
Right brained people are creative
Left brained people are logical

8. The Endocrine System
Contains the glands that release hormones into our bloodstream
Pituitary Gland: releases growth hormones
Thyroid Gland: controls our metabolism
Adrenal Glands: help us with stressful situations
Testes/Ovaries: important for reproduction

9. Heredity: Our Genetic Background
Heredity: passing along traits from parents to offspring
Nature-Nurture Debate: How did we develop who we are?
Through Nature: our genetic make-up
Through Nurture: from our environment

10. Kinship Studies Explore the Nature-Nurture Debate
Twin Studies: look at identical and fraternal twins
Adoptee Studies: look at siblings not raised together
Twins Reared Apart: combines Twin Studies and Adoptee Studies

11. Alone or with a partner…
Find a kinship study. Describe their question, summarize the experiment, and share the results.
Which side of the Nature-Nurture Debate are you on? Are you who you are from genetics or your environment?

12. Sensation & Perception

13. Sensation is basically what the senses take in.
Perception is how we organize and give meaning to what we sense.

14. Affected by…
Absolute Threshold: the weakest amount of stimulus that can be sensed
Example: some of us see better than others
Difference Threshold: our ability to detect small differences between stimuli
Example: can you tell when the radio is turned up

15. Affected by…
Signal-Detection Theory: not only the stimulus, but our mood and attitudes impact perception
Example: motivation can effect whether we excel at an event
Sensory Adaptation: we can get used to stimuli
Example: eyes adjust in a dark theater

16. Vision

17. The Eye The Pupil The black part of the eye
Allows light to enter the eye
Large pupil = more light
Also opens more when we’re afraid!
The Iris: the color of your eye
The Sclera: the white of your eye

18. More on the Eye The Lens: adjusts its thickness to help with distance
Retina: holds the picture of what we’ve seen
Photoreceptors: neurons in the retina
Our blind spot is where the optic nerve leaves the eye

19. Visual Acuity The sharpness of vision
Measured by the Snellen Vision Chart
Nearsighted—can see near, not far away
Farsighted—need glasses for reading

20. Color Vision The Color Circle
Complimentary colors are across from one another
Cones enable us to see colors

21. Color Blindness Most do not see shades of red or green
Total loss is very rare
You should see a 58, 18, E, and 17

22. Afterimage The afterimage of a color is its complimentary color
When you look at the image for 30 seconds and look at a white paper—you’ll see the complimentary colors!

24. Hearing

25. Parts of the Ear The part outside is the outer ear
The eardrum is the “door” from the outer to the middle ear
Three bones in the middle ear: hammer, anvil, and stirrup
In the inner ear, the cochlea moves and sends info to the brain via the auditory nerve

26. How We Hear Sounds travel in waves Each sound has its own
Pitch: how high or low the sound is; determined by the length of the wave
Loudness: how loud or quiet the sound is; determined by the height of the wave
Measured in decibels
About 2 million Americans have no hearing

27. Other Senses

28. Smell and Taste Without smell, we wouldn’t be able to taste
Odors are detected by receptor neurons in the nose
Send info to the brain via the olfactory nerve
Tastes are detected by receptor neurons on the tongue

29. Skin Senses (also called touch)
Pressure
Sensory receptors near the roots of the hair on our bodies give us this sense
Some parts are more sensitive than others (fingertips and lips)
Temperature
Neurons beneath the skin sense temps
It’s all relative to our temp—usually 98.6 degrees
Pain
The more pain receptors, the more sensitive to pain

30. Perception

31. We have certain rules for perception
Closure: we can fill in the blanks
Figure-Ground Perception: we can focus on an object or the background
Perception of Movement: we judge our movement relative to other objects

32. Consciousness

33. Truth or Fiction
If it were not for cues such as the sunrise and sunset, people would act as if a day were 25 hours long.
The only time people dream is just before they wake up.
It is possible to hypnotize any person at any time.
People who are drunk always know that they are drunk.
TRUTH
FICTION

34. The Study of Consciousness

35. Meanings of Consciousness
Consciousness as Sensory Awareness: we are aware of the items we see, smell, taste, hear, and feel
We can be unaware of sensory stimulation
We are more aware of unusual stimuli or intense stimuli

36. Meanings of Consciousness
Consciousness as Direct Inner Awareness: we are aware of things within ourselves (memories, past experiences, etc.)
Consciousness as Sense of Self: we are aware that we are unique individuals, separate from other people and their surroundings

37. Levels of Consciousness
Total Consciousness: we are aware of our awareness
The Preconscious Level: we can answer a question about something by recalling it, even if we aren’t presently thinking about it; we simply direct our attention to it
Ex: What did you have for dinner last night?

38. The Unconscious Level: also called the subconscious; this information is hidden from us and is unavailable
Freud says we “hide” painful memories and certain unacceptable impulses—like aggression
We protect ourselves from feelings of anxiety, guilt, or shame
The Non-conscious Level: includes some basic biological functions
Our fingernails grow, our pupils dilate, we breathe

39. Altered States of Consciousness
A person’s sense of self or senses of the world changes
Examples: sleep, drugs, and medications

40. Sleep and Dreams

41. We sleep about one-third of our lives
Circadian Rhythms: biological clocks, govern how we function; include a sequence of bodily changes (body temperature, blood pressure, and sleep patterns) that occur on a 24-hour schedule

42. Sample Circadian Rhythm

43. The Stages of Sleep
Defined in terms of brain wave patterns measured by EEGs
Four brain wave patterns: alpha, beta, theta, and delta waves
Awake/Alert to Drowsiness
We emit beta waves—short and quick waves
As we relax, we emit alpha waves—a little slower; we may experience flashes of color or feelings of falling

44. The Stages of Sleep
Defined in terms of brain wave patterns measured by EEGs
Four brain wave patterns: alpha, beta, theta, and delta waves

45. Stage One
The lightest stage of sleep
Brain waves move from alpha to the slower rhythm of theta waves
Includes brief images, similar to photographs
We will remember these images if we awake from stage one sleep
Lasts no more than minutes

46. Stages Two to Four
We move from stage two to three to four
Stages 3 and 4 are the deepest stages and we emit the slowest brain waves—delta waves
We have the hardest time waking from stage four sleep
After 50 minutes, we move to stage four and back through the stages to stage one again

47. Rapid Eye Movement / REM Sleep
We breathe more irregularly, our blood pressure rises, and the heart beats faster; our brain wave patterns are similar to stage one (theta waves)
Beneath our closed eyelids, our eyes move quickly
REM sleep becomes longer as we approach morning
REM sleep may help brain development in infants and may exercise brain cells in adults
During 8 hours of sleep, we may go through five sleep cycles (1 to 2 to 3 to 4 to 3 to 2 to 1 to REM to 1 to 2, etc.)

48. Why do we sleep?
For our health: to revive our tired bodies, to build up resistance to infection, we can help recover from stress
When we go without sleep…
Randy Gardner’s study in 1964 found people became irrational
We become irritable, our eyes do not focus, we have speech difficulties and memory lapses
When deprived of only REM sleep, we experience longer REM sleep when we’re able to reach this stage

49. Dreams Characteristics May be in color or black and white
May be realistic or totally disorganized
Sometimes we dream in “real time,” a ten minute dream takes ten minutes for us to dream it
Most dreams are extensions of our daily activities
We often don’t remember dreams because we are unable to hold on to information from one state of consciousness to another

50. Freud’s View
Our dreams reflect our unconscious wishes/urges
Unacceptable and painful wishes may appear in symbolic form

51. The Bio-psychological Approach
Dreams begin when neurons stimulate the section of the brain that controls movement and vision
The brain responds to these random stimuli by creating stories—whatever is stimulated is the basis for our dream
Ex: if the part of our brain that controls running is stimulated, our dream would center on running in some way

52. Sleep Problems

53. Insomnia
Definition: the inability to sleep, usually the inability to fall asleep at bedtime
Racing minds at bedtime
Becomes worse when we try to fall asleep—increases tension
Solution? Sleeping pills or a variety of techniques (tense/relax muscles, avoid worrying in bed, stick to a routine, relax with daydreams/pleasant images)

54. Nightmares/Night Terrors
Definition: dreams that frighten us
Usually affect people who are anxious or depressed
Night terrors: more severe than nightmares, memories may be vague, our hearts race and we gasp for air; tend to occur during deep sleep (stages 3 and 4) and closer to the beginning of sleep
May be due to immature nervous systems; common with children

55. Sleepwalking Definition: roaming around during sleep
Little Sleepwalker

56. Sleep Apnea Definition: breathing interruptions during sleep
May result in being tired in the morning
Caused by blocked air passages
May be linked to SIDS

57. Narcolepsy Definition: falling asleep at any time in any place
Very rare
Go straight to REM sleep
Treated with medication and frequent naps

58. Altered States When We're Awake

59. Meditation Definition: narrowing our consciousness
Techniques: focus on a peaceful, repetitive stimulus
Looking into a candle or oil lamp
Looking at intricate/detailed drawings
Repeating mantras (pleasing sounds like “om”) and focusing on the sounds
Important in some religions (Buddhism)

60. Hypnosis
Definition: a “sleep-like” state in which people respond to suggestions and/or answer questions
Uses
To help people relax, reduce anxiety, manage pain, or overcome fears
As an anesthetic in surgery
Can only occur if the patient is willing!
Effectiveness
Post-hypnotic Suggestion: technique in which behavior changes after hypnosis
Some people have stopped smoking after hypnosis

61. Déjà Vu A feeling of re-experiencing a specific situation
Can be used to relive the experiences of past lives
Some epileptics experience déjà vu prior to having a seizure

62. Lucid Dreaming
A dream in which the dreamer is aware he/she is dreaming
Can happen naturally
Through training, people are able to place themselves into dreams
Used to relax and relieve stress
Is different from dream control in which the dreamer directs his/her dreams

63. Drugs and Consciousness

64. Depressants
Definition: drugs that slow down the nervous system (breathing, movement, etc.); may make people feel relaxed

65. Examples of Depressants
Alcohol
Small doses may make people feel relaxed, but large doses can up a person to sleep
Narcotics: addictive depressants used to relieve pain and induce sleep
Includes: morphine, heroin, and codeine
Users may suffer withdrawal symptoms (tremors, chills, cramps, rapid heartbeat, insomnia, vomiting, and diarrhea)

66. Stimulants
Definition: drugs that increase the activity of the nervous system
Examples
Nicotine
Spurs the release of adrenaline, which increases the user’s heart rate
Reduces the appetite and increases metabolism
Is addictive; quitters suffer from withdrawal
Can cause serious health risks and thus the surgeon general’s warnings

67. Another Example Amphetamines (speed)
Known for helping people stay awake and reducing one’s appetite
High doses can produce feelings of pleasure and highs, but the users usually “crash” or come down quickly and become depressed
Can lead to hallucinations (people see/hear things that aren’t real—seeing/feeling bugs crawling all over you) and delusions (a false idea that seems real—thinking you can fly)

68. Hallucinogens
Definition: a drug that produces hallucinations; may produce feelings of pleasure, but may also induce panic
Examples
Marijuana: leads to relaxation and very mild hallucinations
Can impair perception, coordination, memory, and learning
Used to treat minor aches and pains over 100 years ago (like Tylenol and aspirin today)

69. Another Example
LSD/Acid: much stronger than marijuana, produces strong hallucinations
Users claim they become extremely creative, but may forget when the effects wear off
Effects are not predictable
Long or continuous use can lead to flashbacks

70. Drug Abuse Treatments Detoxification: remove the drug from the body
Maintenance Programs: participants are given controlled amounts of the drug or a less addictive substitute
Example: nicotine gum to help quit smoking
Counseling: individually or in groups
Support Groups: include several people who share similar experiences, concerns, or problems; useful to provide emotional and moral support
Example: Alcoholics Anonymous