Can We Trust Perception? (Pt. 2): Motivated Perception

Transcription

1 Can We Trust Perception? (Pt. 2): Motivated Perception PSYCH 1101: DAY 13 PROF. DAVID PIZARRO CORNELLPSYCH.NET

2 Exam Info At The End Of Class

3 Do Beliefs, Desires, Motivations, Etc. Influence Perceptual Processes?

4 Do We See Things Differently? The New Look movement in psychology argued that yes Desires and motives infuse perception: poor children see coins as larger New look research received a number of criticisms Poor children less familiar with coins Assessments were not of actual perception Memory Judgment Attentional shifts

5 The New New Look EMILY BALCETIS DAVID DUNNING DENNIS PROFFITT

6 1. Motivated Perception Of Ambiguous Figures

7 Balcetis & Dunning (2006) Participants are introduced to a taste-testing study with two conditions: Desirable foods: Such as jelly beans Undesirable foods: Such as a can of beans Participants are assigned by playing a computerized card game Their assignment depends on whether they see a farm or sea animal

8 Horse Or Seal?

9 First Eye Movement Eye Movements Indicate Horse Seal Which Is Favorable Horse Seal

10 2. Motivated Perception Of Rival Binocular Images

11 View-Master

12 Binocular Rivalry

13 Balcetis, Dunning & Granot (2010) Subjects presented binocular images that were either letters or numbers Images presented at 300 ms (fast enough for a conscious experience, but not to start thinking about it)

14 More Likely To See Winning Category Letters Numbers Which is Desirable?

15 3. Motivated Perception Of Distance

16 Balcetis & Dunning (2010) Are desirable things perceived to be closer? Manipulated how thirsty participants were Thirsty: eat bowl of pretzels (40% of daily sodium) Quenched: drank up to four 8-oz. glasses of water Distance to object: self-generated response

17 How Far Away Is The Water? (Actual Distance = 36 Inches) 30 Distance (in) Thirsty Quenched

18 Beanbag Toss: Throwing Instead Of Reporting An Estimate

19 Valuable Gift Card -9.1

20 Worthless Gift Card +1.3

21 How Far Away Is The $100 Bill? (Actual Distance = 55 Inches) CHANCE TO WIN! = 50.8 INCES

22 How Far Away Is The $100 Bill? BELONGS TO EXPERIMENTER = 58.9 INCHES

23 4. Motivated Perception Of Steepness

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25 Fatigue Influences Steepness Estimates (Proffitt And Friends) Joggers: Before vs. After a run Before = 21 degrees After = 28 degrees Wearing a backpack increases estimates of the steepness of a ramp

26 So Yes? Not Really. Many of these new studies fall prey to similar criticisms This is not perception, but a higher level process such as attention, memory, or belief Some of these effects can be made to go away fairly easily (subjects who wear a backpack because they think it contains sophisticated measuring equipment do not show the biased estimates) Ambiguous shapes have no absolute interpretation, so a higher level process HAS to kick-in to disambiguate the shape Finally, many of the most impressive perceptual effects require, at some level, that the participant have perceived accurately--knowing that one side has letters and the other has shapes is necessary to show bias in the first place

27 New New Look Still Provides Critical Insight Motivations, beliefs, and desires can influence a great deal of very basic processes--whether they are perceptual or not Biases can act completely outside of conscious awareness New Look arguments have been successful across a range of perceptions that were previously thought to be impenetrable. The only question that is still argued is how EARLY in the stage these effects occur But at a VERY early stage, the evidence is still there--we have a reliable set of perceptual systems.

28 Prelim Exam On Monday Exam covers all lectures (including today s), textbook chapters 1-5, and Chomsky article from your reader. Format: 50 multiple choice questions--test sheets and Scantrons (provided). Pencils not provided. Sample questions posted on course website There are no desks in Bailey. Please bring something on which to write (that is not your textbook), or else you ll be writing on your lap! The class immediately following this one has an exam. Be here on time! Exams that have not been turned in by the 11:00 sharp will be snatched.

29 Prelim 1 Review Sessions Psych Tutors answer your questions 202 Uris Hall Saturday at 11:00 am Saturday at 4:00 pm Sunday at 2:00 pm