Monkeys reason about perceptions - they recognize that perception leads to knowledge No evidence that monkeys represent false beliefs - similar pattern of findings in other nonhuman primates (chimpanzees)

1. Mental state representation
insights from non-human primates
Alia Martin
Harvard University
Lecturer, Victoria University of Wellington, New Zealand (2016)

2. Cognitive Origins

5. How do monkeys reason about
the world around them?

7. cameraperson
presenter
monkey

8. How do monkeys reason about
mental states?

9. Reasoning about visual perception

10. Flombaum & Santos (2005)
Reasoning about visual perception

11. Facing
MONKEY
Compe8tor
Facing
AWAY
Compe8tor
Results

12. Flombaum & Santos (2005)

13. Santos, Nissen, & Ferrugia (2006)
Reasoning about auditory perception

14. Santos, Nissen, & Ferrugia (2006)
Reasoning about auditory perception

15. Santos, Nissen, & Ferrugia (2006)
Reasoning about auditory perception

16. Santos, Nissen, & Ferrugia (2006)
Reasoning about auditory perception

17. 0
2
4
6
8
10
12
14
NOISY
SILENT
# of
Monkeys
Santos, Nissen, & Ferrugia (2006)
Results
*

18. Santos, Nissen, & Ferrugia (2006)
Reasoning about auditory perception

19. Santos, Nissen, & Ferrugia (2006)
Results
*
0
2
4
6
8
10
12
# of
Monkeys
NOISY
SILENT

20. Monkeys reason about
perceptions…
What about beliefs?

21. Monkeys reason about
perceptions…
What about beliefs?

22. False Beliefs in Infants
False BeliefTrue Belief
EXPECTED EXPECTEDUNEXPECTED UNEXPECTED

23. Results
0
5
10
15
20
25
LookingTime(s)
expected unexpected expected unexpected
TRUE BELIEF FALSE BELIEF
*
*

24. False Beliefs in Monkeys?

25. Do monkeys reason about
beliefs to predict behavior?

26. Can monkeys represent false beliefs?
True Belief False Belief
EXPECTED EXPECTEDUNEXPECTED UNEXPECTED

27. NOW: Monkey Results
.
1
2
3
4
5
0
FALSE BELIEFTRUE BELIEF
EXPECTED UNEXPECTED EXPECTED UNEXPECTED
DURATIONOFLOOKING
(SECONDS)
*

28. Monkeys reason about
perceptions…
What about beliefs?
Not to predict behavior…
Do they show any sensitivity to
beliefs?

29. Automatic Belief Processing

30. Automatic Belief Processing
Kovacs, Teglas, & Endress (2010)

31. Kovacs, Teglas, & Endress (2010)
Automatic Belief Processing

32. Kovacs, Teglas, & Endress (2010)
Automatic Belief Processing

33. Baby Thinks Agent Thinks Outcome
empty empty empty
empty empty
empty empty
empty
EXPECTED
Automatic Belief Processing

34. Kovacs, Teglas, & Endress (2010)
Automatic Belief Processing

35. Kovacs, Teglas, & Endress (2010)
?
Automatic Belief Processing

36. Baby Thinks Agent Thinks Outcome
empty empty empty
empty
empty empty
empty empty
EXPECTED
UNEXPECTED
Automatic Belief Processing

37. Kovacs, Teglas, & Endress (2010)
Automatic Belief Processing

38. Kovacs, Teglas, & Endress (2010)
?
Automatic Belief Processing

39. Baby Thinks Agent Thinks Outcome
empty empty empty
empty
empty empty
empty empty
EXPECTED
UNEXPECTED
Automatic Belief Processing

40. Baby Thinks Agent Thinks Outcome
empty empty empty
empty
empty empty
empty empty
EXPECTED
UNEXPECTED
UNEXPECTED
Automatic Belief Processing

41. Baby Thinks Agent Thinks Outcome
empty empty empty
empty
empty empty
empty empty
EXPECTED
UNEXPECTED
UNEXPECTED
UNEXPECTED
Automatic Belief Processing

42. Are monkeys automatically
influenced by others’ beliefs?

43. Automatic Beliefs in Monkeys?

44. Procedure

45. Familiarization 1

46. Familiarization 2

47. Automatic Beliefs in Monkeys?
Monkey TRUE BELIEF
Human TRUE BELIEF
Monkey FALSE BELIEF
Human FALSE BELIEF
TEST
Monkey TRUE BELIEF
Human FALSE BELIEF
Monkey FALSE BELIEF
Human TRUE BELIEF

48. 0
1
2
3
4
Monkey TB Monkey FB
LookingTime(s)
Agent TB
Agent FB
Results
Human TB
Human FB

49. Conclusion
Monkeys reason about perceptions
- they recognize that perception leads to
knowledge
No evidence that monkeys
represent false beliefs
- similar findings in other nonhuman
primates (e.g., chimpanzees)

50. Conclusion
Monkeys reason about perceptions
- they recognize that perception leads to
knowledge
No evidence that monkeys
represent false beliefs
- similar findings in other nonhuman
primates (e.g., chimpanzees)

51. Conclusion
Monkeys reason about perceptions
- they recognize that perception leads to
knowledge
No evidence that monkeys
represent false beliefs
- similar findings in other nonhuman
primates (e.g., chimpanzees)

52. Conclusion
Monkeys reason about perceptions
- they recognize that perception leads to
knowledge
No evidence that monkeys
represent false beliefs
- similar pattern of findings in other
nonhuman primates (chimpanzees)

53. Thank you
Laurie Santos CPRC