V. Thought and Behavior: Do we control our own minds?

1. Brain, Mind, and Belief: The Quest for Truth V. Thought and Behavior: Do we control our own minds? ... the brain creates a picture -- a simulation that we mistake for reality. George Johnson

2. Today’s Agenda • Traveling the brain's pathways • Thinking with categories • Unconscious influences on behavior

3. REVIEW Operations in neurocognitive networks • Activation moves along lines and through nodes • (along the pathways of the brain) • Integration • Broadcasting • Connection strengths are variable • A connection becomes stronger with repeated successful use • A stronger connection can carry greater activation

4. REVIEW Some nodes of the cortical net for fork Each node in this diagram represents a cortical column C T M C — conceptual M — motor T — tactile V — visual V

5. Some nodes of the cortical net for fork T M C PP P V PA

6. Some nodes of the cortical net for fork T M C PP P V PA

7. A word network with two subnets partly shown T C PP PR PA V M C – Cardinal concept node M – Memories PA – Primary auditory PP – Phonological production PR – Phonological recognition T – Tactile V – Visual Visual features

8. Ignition of a word network from visual input T C PR Art PA V M

9. Ignition of a word network from visual input T C PR Art PA V M

10. Ignition of a word network from visual input T C PR Art PA V M

11. Ignition of a word network from visual input T C PR Art PA V M

12. Ignition of a word network from visual input T C PR Art PA V M

13. Ignition of a word network from visual input T C PR Art PA V M

14. Ignition of a word network from visual input T C PR Art PA V M

15. Ignition of a word network from visual input T C PR Art PA V M

16. Ignition of a word network from visual input T C PR Art PA V M

17. Ignition of a word network from visual input T C PR Art PA V M

18. Ignition of a word network from visual input T C PR Art PA V M

19. Ignition of a word network from visual input T C PR Art PA V M

20. Ignition of a word network from visual input T C PR Art PA V M

21. Speaking as a response to ignition of a net T C PR Art PA V M

22. Speaking as a response to ignition of a net T C PR Art PA V M

23. Speaking as a response to ignition of a net T C PR Art PA V M From here (via subcortical structures) to the muscles that control the organs of speech articulation

24. An MEG study from Max Planck Institute Levelt, Praamstra, Meyer, Helenius & Salmelin, J.Cog.Neuroscience 1998

25. Thinking: Traveling the pathways of the brain • Starting a trip through the brain’s pathways • Often induced by sensory input • Hearing the telephone ring • Seeing your cat scratching a favorite chair • Often initiated internally • Using information already present in the mind

26. Internally induced mental processing • Operates with previously acquired information • Deduction, induction, reasoning, figuring things out, connecting the dots, … • Examples: thinking about .. • The story that Santa comes down the chimney • The story of Noah’s ark and the great flood 

27. Today’s Agenda • Traveling the brain's pathways • Thinking with categories • Unconscious influences on behavior

28. Categories and reality • Categories are in the mind, not in the real world • In the world, everything • is unique • lacks clear boundaries • changes from day to day • (even moment to moment) • Whorf: “kaleidoscopic flux”

29. Types of Conceptual Categories • Discrete – clear boundaries • Even integers • Towns in MA • Radial – membership comes in degrees • Birds • Vehicles • Family resemblance • Games • Furniture • Ill-defined, vague • Thought • Mind

30. Properties of radial categories • No small set of defining features • Example: CUP • What’s the difference between a cup and glass? • Fuzzy boundaries • Example: VEHICLE • Car, truck, bus • Airplane? • Boat? • Toy car, model airplane? • Raft? • Roller skate? • Snowboard? • Prototypicality • Prototypical vehicles: CAR, TRUCK, BUS • Peripheral vehicles: AIRPLANE, TOY CAR, RAFT, ROLLER SKATE, etc

31. How do radial categories work? • We can understand how they work by understanding how they are represented in the cortex • Different connections have different strengths (weights) • More important properties have stronger connections • For CUP, • Important properties: • Short (as compared with a glass) • Ceramic • Having a handle • These properties are not necessary • But cups with these properties are more prototypical

32. The properties of a category have different weights The cardinal node The threshold CUP T MADE OF GLASS SHORT CERAMIC HAS HANDLE The properties are represented by nodes, which are connected to lower-level nodes More important properties have greater weights, represented by greater thicknesses of lines

33. Activation of a category node • The node will be activated by any of many different combinations of properties • The key word is enough – it takes enough activation from enough properties to satisfy the threshold • The node will be activated to different degrees by different combinations of properties • When strongly activated, it transmits stronger activation to its downstream nodes.

34. Radial categories and inference These connections are bidirectional CUP T MADE OF GLASS SHORT CERAMIC HANDLE Separate fibers for the two directions; shown as one line in the notation

35. An important finding from neuroanatomy • Cortico-cortical connections are generally reciprocal • If there is a connection from A to B there is also a connection from B to A • Consequence: Bidirectional processing A B

36. Bidirectional processing and inference Thought process: 1. The cardinal concept node is activated by a subset of its property nodes 2. Feed-backward processing activates other property nodes Consequence: We “apprehend” properties that are not actually perceived CUP T SHORT HANDLE

37. Category Structure and Inference Category T Consequence: If A and B, then E and F A B F E C D Properties

38. Examples • Dark clouds, thunder • It’s going to rain • Ceramic, cup-shaped, handle • Probably holds coffee (without breaking) • ATM • Probably has money • Afro-American trying to break into house • Must be a burglar

39. Categories and cognitive malfunction • Underdifferentiation • Assuming that members of a category are alike • Illusory properties • Assuming that a category has one defining feature • Assuming that members of a category share some properties that are lacking in those outside the category • Illusory category boundaries • Or: failure to recognize ‘fuzziness’

40. Categories and cognitive malfunction • Underdifferentiation • Assuming that members of a category are alike • Illusory properties • Assuming that a category has one defining feature • Assuming that members of a category share some properties that are lacking in those outside the category • Illusory category boundaries • Or: failure to recognize ‘fuzziness’

41. Category errors with consequences Example: Dietary fats • Original report: JAMA, 8 Feb 2006 • Big news: Front page of NY Times. Etc. • “Landmark Study” • 48,835 women • Eight years • $415 million • Study finds that reducing fat intake does not confer health benefits • Co-author: JoAnn Manson, chief of preventive medicine at Harvard’s Brigham and Women’s Hospital • MSNBC: “…respected nutrition authority”

42. Category errors with consequences Example: Dietary Fats MSNBC: 8 Feb 2006: Study: Low-fat diet fails to decrease cancer, heart risks in older women “Eating less fat late in life failed to lower the risk of cancer and heart disease among older women, disappointing news for those who expected greater benefits from a healthy diet.” … “The eight-year study showed no difference in the rate of breast cancer, colon cancer, and heart disease among those who ate low-fat diets and those who didn’t.” … “The study, appearing in Wednesday’s Journal of the American Medical Association, is part of … a landmark government project involving tens of thousands of … U.S. women.”

43. Exercise: What is wrong with this study?And with the press report on this study? • Answer: They didn’t consider the differences between different kinds of fat • A category error • All members of the category treated as alike

44. There are different kinds of FAT From the web site of the FDA Type of Fat Example Good/Bad

45. Categories and cognitive malfunction • Underdifferentiation • Assuming that members of a category are alike • Illusory properties • Assuming that a category has one defining feature • Assuming that members of a category share some properties that are lacking in those outside the category • Illusory category boundaries • Or: failure to recognize ‘fuzziness’

46. Illusory properties • Assuming that a category has one defining feature • Example: MAN • What is it that distinguishes humans from other animals? • Proposal: “tool-making animal” • (Caution: TOOL is a category) • Assuming that members of a category share some properties that are lacking in those outside the category • White supremacy

47. Categories and cognitive malfunction • Underdifferentiation • Assuming that members of a category are alike • Illusory properties • Assuming that a category has one defining feature • Assuming that members of a category share some properties that are lacking in those outside the category • Illusory category boundaries • Or: failure to recognize ‘fuzziness’ • Example: BEARD

48. Today’s Agenda • Traveling the brain's pathways • Thinking with categories • Unconscious influences on behavior

49. Unconscious influence of language on behavior:Experiments with “scrambled sentence test” • Experiments by John Bargh and colleagues • Bargh, Chen, and Burrows, 1996 • Scrambled sentence test • “The purpose of the study is to investigate language proficiency” • Task: Write down a grammatically correct sentence using only four of the five words given

50. Sample “scrambled sentence” data • him was worried she always • shoes give replace old the • sky the seamless gray is • should now withdraw forgetful we • us bingo sing play let • sunlight makes temperature wrinkle raisins • from are Florida oranges temperature • be will sweat lonely they