1. Sensation and Perception
Sensation: your window to the world
Perception: interpreting what comes in your window.

2. Sensation
Sensation – process of detecting a stimulus through sensory receptors and the nervous system.
Process of sensing our environment through taste, sight, sound, touch and smell
Example:
Hearing Mrs. Joseph speak, the sound waves travel to the ears. The hair on the cells in the cochlea help transmit the information to the brain
Prosopagnosia – face blindness
All sensation, no perception
Definition –Sensation: your window to the world
process of receiving and representing stimulus energies by the nervous system; detection and encoding of stimulus energies
Complete sensation without perception = prosopagnasia
Sensation - As you look at an apple, its reflected light travels to the eye. The rods and cones absorb the light and help transmit the information to the brain

3. Perception
Perception – process by which we select, organize, and interpret sensory information to recognize meaningful objects and events
Based on our prior experiences and expectations
Example:
Seeing letters on a page (sensation)interpreting them as our favorite passage in a novel (perception)
Definition - Perception: interpreting what comes in your window.
The process by which we select, organize, and interpret sensory information in order to recognize meaningful objects and events is called
Ex. Perception - As the brain receives information about the lines, angles, and edges of objects in the environment, higher-level cells process and interpret the information to consciously recognize objects.
Sensation = detection; perception is interpreting
Hearing a sound sequence vs. as recognizing it as a melody

8. Bottoms-up Processing
Bottoms Up Processing (AKA - Feature analysis)
Begins with the sensory receptors and works its way up to the brain
Use the features of the object itself to process the information
Examples:
seeing the individual fruits in this picture
Hearing a voice speak about AP Psych
Definition: Analysis that begins with the sensory receptors and works up to the brain
Example Trying to see a hidden representational image in a piece of abstract art by looking carefully at each element in the picture and trying to form an image

9. Top Down Processing
Top Down Processing - Processing information from the senses with higher level mental processes using our experiences and expectations
Using your background knowledge to fill in the gaps
Examples:
Seeing the face in the picture made up of fruit
I _ope yo_ get an 5 on t_ _ A _e_am
Negative expectations about the pain of childbirth can increase pain during the birthing process
Effect of prior experience and current expectations on perception
Start from the top and work in the details
Negative expectations about a surgical procedures can increase post operative pain
Prosopagnasia = deficiency in top down processing

10. Find the following hidden items:
Scissors
Banana
Screwdriver
Horn
Heart
fish
boat
Shoe
needle

11. Aoccdrnig to a rscheearch at an Elingsh uinervtisy, it deosn’t mttaer in what oredr the ltteers in a word are, th olny iprmoetnt tihng is that frist and lsat ltteer is at the rghit pclae. The rset can be a toatl mses and youcan still raed it wouthit a porbelm. This is bcuseae we do not raed erveylteter by it slef but the word as a wlohe.

12. Selective Attention
Selective Attention - Ability to focus our conscious awareness on a particular stimulus
Example: Cell phone usage while driving a car
For example - students in class should focus on what the teachers are saying and the overheads being presented. Students walking by the classroom may focus on people in the room, who is the teacher, etc., and not the same thing the students in the class.
Nose is in your line of vision
Cell phone usage while driving a car
Because she was listening to the news on the radio, Mrs. Schultz didn't perceive a word her husband was saying. Activity of tapping shoulder while doing something else

13. Selective Attention Example
Say the name of the color the word is written in.

14. The Stroop Effect
Stroop Effect – the difficulty attending to the color because of the interference with the meaning of the word
The interference between the different information (what the words say and the color of the words) your brain receives causes a problem.

15. Cocktail-party phenomenon
cocktail party effect - ability to focus one's listening attention on a single talker among a mixture of conversations and background noises, ignoring other conversations.
Form of selective attention.
Example:
You are at the football game and are cheering for the Comets when you hear Ms. Short call your name
The ability to pay attention to one voice at a time.

16. Create your own examples Pick two that you are having the most difficulty with and make your partner come up with a new example
Sensation
Perception
Bottoms-up processing
Tops-down processing
Selective Attention
Stroop Effect
Cocktail Party effect
No stinky examples!

17. Selective Inattention
Change Blindness/Inattentional Blindness - Falling to notice changes in the environment
Example: Eating your lunch in the cafeteria, when your friend switches your sandwich and you don’t notice
Choice Blindness - failure to notice a switch in a choice that is made
Example: Participants asked to pick between two photographed faces, when photographs are switched…
Change deafness – failure to notice a change in voices that are speaking
Example: Listening to Mrs. Joseph speak, failure to notice that Mrs. Harvey is now speaking
Change blindess/Inattentional Blindness – gorilla and basketball; When Jason briefly turned to summon the waiter, his wife quickly switched her glass of red wine with his glass of white wine; While a man provided directions to a construction worker, two experimenters rudely interrupted by passing between them carrying a door. The student's failure to notice that the construction worker was replaced by a different person during this interruption
Choice Blindness - Research participants picked one of two photographed faces as more attractive. When researchers cleverly switched the photos, participants readily explained why they preferred the face they had actually rejected
Pop out - The pop-out phenomenon illustrates that some stimuli almost inevitably trigger
Change deafness example: Researchers found that 40 percent of people focused on repeating a list of challenging words failed to notice a change in the person speaking.

18. Pop Out Effect
Pop out – stimuli we don’t chose to attend to but they draw our eyes and demand our attention
Example: Picture on the left

19. Complete sensation in the absence of complete perception is best illustrated by
Weber’s Law
Prosopagnosia
Conduction deafness
Color constancy
Sensory interaction 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

20. Sensory adaptation Parallel processing Sensation Perception
The process by which we select, organize, and interpret sensory information in order to recognize meaningful objects and events is called
Sensory adaptation
Parallel processing
Sensation
Perception
accomodation 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

21. Difference thresholds Top down processing
Patients' negative expectations about the outcome of a surgical procedure can increase their postoperative experience of pain. This best illustrates the importance of
Transduction
Accomodation
Sensory adaptation
Difference thresholds
Top down processing 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

22. Researchers found that 40% of people focused on repeating a list of challenging words, failed to notice a change in the person speaking. This illustrates
Top Down Processing
Bottoms up Processing
The Difference Threshold
Change Deafness
Perception

23. Subliminal perception Change blindness Perception Selective Attention
You typically fail to consciously perceive that your own nose is in you line of vision. This illustrates
Subliminal perception
Change blindness
Perception
Selective Attention
The cocktail party effect

24. Psychophysics
Psychophysics - Study of how physical stimuli are translated into psychological experience.
Psychologists use thresholds to measure these events
Example: Tracking a person’s eye movements jumping every .33 of a second
Relationship between physical stimuli and psychological effects
Eyes are constantly moving, quivering
Univ. of Edinburgh psychologist John Henderson illustrates how a person’s gaze jumps from one spot to another every third of a second or so. Picture shows where person’s eye jumps on this photograph. Circles represent fixations and the numbers indicate the time of fixations in milliseconds

25. Thresholds
Threshold – the point at which sensory information is strong enough to be noticed
Absolute threshold – minimum stimulation needed to detect a stimulus (light, sound, pressure, taste or order) 50% of the time
Examples:
Light
A candle flame at 30 miles on a dark, clear night.
Sound
The tick of a mechanical watch under quiet conditions at 20 feet.
Taste
One teaspoon of sugar in two gallons of water.
Smell
One drop of perfume diffused into the entire volume of a three-bedroom apartment.
Touch
The wing of a bee falling on your cheek from a distance of one centimeter.
Point at which a stimulus goes from undetectable to detectable – softest touch, faintest sound
Catarax – absolute threshold for light would increase
If have difficulty hearing, seeing, smelling etc., sensation would be below absolute threshold; absolute threshold increases for that sensation
Standing atop a mountain on an utterly dark, clear night, most of us would see a candle flame atop another mountain 30 miles away
You can smell a skunk, but I can’t. You have a lower absolute threshold
If you can’t smell, taste, hear something, you have a lower absolute threshold

26. Absolute Threshold

27. Signal Detection Theory
Signal Detection Theory -Predicts how and when we detect a signal amid background noise
Assumes no absolute threshold
Detection depends partly on a person’s experience, expectations , motivation and alertness…people respond differently to same stimuli
Example: Enemy submarine,
Waiting for the Pizza man to come at a busy party
Cancer: Hit = cancer present, doctor detects it; miss – cancer present doctor misses
False alarm – cancer absent, doctor detects it; correct rejection – cancer absent, doctor doesn’t detect
Signal detection emphasizes - Personal expectations and experience influence the level of absolute threshold .
People respond differently to the same stimulis
Ms. Pace has a reputation for catching kids cheating. She has a low absolute threshold for detecting cheating on exams, but she fails to detect when a clerk at a store tries to cheat her.
Fear can increase your sensitivity to an almost imperceptable pain
Waiting for pizzaman to deliver pizza:
An exhausted forest ranger may notice the faintest scent of a forest fire, whereas much stronger but less important odors fail to catch her attention.
The fact that fear may increase your sensitivity to an almost imperceptible pain stimulus
When expecting a text to come in you are more likely to notice it the second it arrives
Hit - Doorbell rings (pizza here) you answer the door
Miss – Doorbell rings, you don’t answer the door
False alarm – door doesn’t ring, you answer the door
Correct rejection – door bell doesn’t ring, you don’t answer the door

28. Subliminal Stimulation
Subliminal – below one’s absolute threshold for conscious awareness
Example:
Listening to tapes in your sleep to get you to lose weight
Priming – increased sensitivity to certain stimuli due to prior experience outside conscious awareness
Example: Seeing a picture of a mouse before viewing the picture on the left
Subliminal Message – a message below the absolute threshold
Audiotapes of soothing ocean sounds accompanied by faint and imperceptible verbal messages designed to increase a desire to lose weight best illustrate subliminal messages
For example, an individual who has just purchased a new car may now start to notice with more frequency other people driving her same make and model. This person has been primed to recognize more readily a car like hers because of the experience she has driving and owning one.
Priming Example - Photographs of people were rated more positively if the photos immediately followed a briefly flashed image of kittens.

29. Do Subliminal Messages work?
Based on studies, some people do respond to stimuli below the absolute threshold, under some circumstances.
People behave differently at different threshold levels
Priming can briefly influence preferences or perceptions
Complex behaviors are NOT influenced by subliminal messages
Some people are more suggestible than others
Placebo effect 25 50 75
100
Low
Absolute
threshold
Medium
Intensity of stimulus
Percentage
of correct
detections
Subliminal
stimuli
Those who believe in the value of subliminal audiotapes would be wrong to claim that subliminal messages are unusually persuasive
studies do not support the claim that subliminal messages can affect behaviors such as shoplifting. Stimuli presented below the absolute threshold can briefly influence preferences or perceptions (students might mention priming or examples of priming), but no studies have shown that subliminal stimuli can influence complex behaviors such as shoplifting.

30. Think Pair Share
What is the difference between absolute threshold and signal detection theory?
You are conducting an experiment with participants who are listening to music that is gradually increased in volume. Describe a hit, miss, correct rejection, & false alarm for this scenario
According to signal detection theory, will the participant always raise their hand at the same volume level if the experiment is repeated?
What are priming and subliminal messaging?

31. Just noticeable difference

32. Just noticeable difference

33. Just noticeable difference

34. Just noticeable difference

35. Just noticeable difference

36. Just noticeable difference

37. Just noticeable difference

38. Just noticeable difference

39. Just noticeable difference

40. Just noticeable difference

41. Just noticeable difference

42. Just noticeable difference

43. Just noticeable difference

44. Difference Threshold
Difference Threshold (AKA Just Noticeable Difference) – the amount a change needed in a stimulus (stronger or weaker) for us to recognize the change has occurred
the greater the intensity (ex., weight) of a stimulus, the greater the change needed to produce a noticeable change.
Example:
Some people are better at detecting slight variations in the taste of pop
Some people are better than others at detecting slight variations in the tastes of various blends of coffee.

45. Weber’s Law
Weber’s Law (Related to JND) - For people to really perceive a difference, the stimuli must differ by a constant "proportion" not a constant "amount".
Proportion varies depending on the stimulus
If the just-noticeable difference for a 10-ounce weight is 1 ounce, the just noticeable difference for an 80-ounce weight would be 8 ounce(s).
Giulio's bag of marbles is twice as heavy as Jim's. If it takes 5 extra marbles to make Jim's bag feel heavier, it will take 10 extra marbles to make Giulio's bag feel heavier

46. Weber’s Law JND Example:
Pitch = .003 ( if someone sings a little off key, we will be able to tell)
Loudness = .10
Saltiness = .20
Light = .08
Example:
JND for a 10oz weight = 1 oz. To notice a 50 oz weight would be 5oz
JND for a 10 decibel sound = .10 decibels . To notice a sound of 30 decibels would be _______?
The principle that two stimuli must differ by a constant proportion for their difference to be perceived

47. Sensory Adaptation
Sensory Adaption - Diminished sensitivity as a consequence of constant stimulation
Example:
Jumping into a cold swimming pool, doesn’t feel cold after a while
Your eyes when you turn off the lights
Sensory adaptation helps us to focus our attention on novel stimuli
After listening to your high-volume car stereo for 15 minutes, you fail to realize how loudly the music is blasting.
The constant quivering movements of our eyes enable us to
Do you feel your underwear all day?

48. After listening to the television for 10 minutes, you fail to notice how loud the volume is. This is an example of
Weber’s Law
Habituation
Sensory adaptation
Just noticeable difference
Absolute threshold 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

49. Signal detection theory Just noticeable difference Weber’s law
Which theory emphasizes that personal expectations and motivations influence the level of absolute thresholds?
Signal detection theory
Just noticeable difference
Weber’s law
Bottoms-up theory
Tops-down theory 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

50. Adaptation threshold Difference threshold Absolute threshold
The minimum amount of stimulation a person needs to detect a stimulus 50 percent of the time is called the
Adaptation threshold
Difference threshold
Absolute threshold
Subliminal threshold
Change threshold 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

51. A subliminal message is one that is presented
while an individual is under hypnosis.
below one's absolute threshold for awareness.
in a manner that is unconsciously persuasive.
with very soft background music.
Repetitiously 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

52. If I have a 100 watt bulb and can notice a change in the light getting brighter at 108 watts, at what point will I notice a 300 watt bulb getting lighter
308
2400
924
324
908

53. Subliminal messaging vs. Priming
Why the difference between priming studies and subliminal message studies?
priming: immediate, short-term effect on simple judgments and actions
subliminal messages: aim for long-term effects on consumer purchases, voter sentiment, or even suicide – most studies not proven to provide long term effects