Lecture 3 - Do Apes have ToM? Flashcards
What are the 2 possibilities of language being unique to humans?
1: Chimps mind seems similar precisely because it is similar. share ability think about mental states.
2. We cannot help distorting chimps mind, recreating it in our own image.
Outline Premack and Woodruff 1978 do chimps have ToM?
First individuals study this area.
Video woman stressful situations. Shown picture cards with solutions to scenarios. Successfully match. Reason about intention of human.
Who were the first researchers to look at chimps having ToM?
Premack and Woodruff 1978
Outline Woodruff and Premack 1979 study on food and ToM
Humans cooperated with chimp in finding goal. Chimp produce and comprehend behavioural cues. Human and chimp competed. Chimp learned withhold info or mislead recipient
Criticism of Woodruff and Premack’s 1979 study
Only occurred after a lot of training.
Perhaps only learnt 2 rules. Competing = experimenter wore hat, cooperating = did not. Perhaps just learnt association with presence or absence of hat. 2 out 4 chimps successful = not easy to acquire.
Who are the 2 camps in the debate?
Povinelli Camp
Tomasello Camp
Outline the Povinelli Camp
Chimps do not reason about others’ beliefs or any other mental states.
Same behaviours, but not same underlying psychological mechanisms.
Outline the Tomasello Camp
Chimps have ToM in some respects, but not in others.
No evidence whether they understand FB
BUT: Chimps understand goals and intentions and perception and knowledge of others.
Outline the Behavioural Abstraction Hypothesis
Understand only surface-level. Form behavioural rules.
Abstract categories of behaviour
Make predictions future behaviour that follow from past behaviours and adjust their own behaviour accordingly.
What are the Behavioural Rules of the Behavioural Abstraction Hypothesis
Chimps highly social animals. Need anticipate what others do.
Anticipate actions based goals and intentions.
Inferring states not only in previously observed situations, also in novel situations.
Outline Call and Tomasello 2008 study on understanding goals and intentions?
summarised 10 studies. Infants and chimps show understanding goals or intentions.
Chimps leave earlier and beg more intensely from experiment who is unwilling opposed unable deliver food. Reasoning about mental states.
What studies contradict Pavinelli’s behavioural abstraction hypothesis
Imitation studies
Outline Buttelmann et al 2007 study on understanding goals and intentions
Demonstration human interacting with target. Either hitting it with his foot as his hands were full or with his hands empty, Chimps imitate rationally. Imitated behaviour when seemed do it intentionally not due physical constraint.
Chimps understand others goals and intentions
Outline Warneken and Tomasello 2006 study procedure
altruistic motivation = no benefit/costly.
24x 18 month olds. 3x 36-54 month old chimps.
10 situations 4 categories. Out of reach, Access thwarted by physical object, Achieving wrong result, Using wrong means.
3 request phases - 10 focus, 10 alternative gazes, 10 verbalise.
Results of Warneken and Tomasello 2006 study on altruistic motivation
Children and chimps both willing help without reward or praise.
6 out 10 trials more likely to help. Show difference between control and experimental. Reason between when people do and don’t need help.
Chimps helped more in reaching tasks than other tasks.
Best competitive than cooperative as in wild more competitive.
Why does Warneken and Tomasello 2006 study contradict Povinelli’s behavioural abstraction hypothesis
Lot these situations novel and chimps respond appropriately.
Not just learnt rules.
Pavinelli and Eddy 1996 - Can chimps follow gaze?
Chimps understand there are targets we look at it. Target cannot be what I cannot see. If there is a barrier stopping chimp seeing what human is looking at Chimp will try and look around barrier.
Pavinelli and Preuss 1995, and Pavinelli and Eddy 1996 - Understanding perception? Negative evidence.
Chimps beg food from blindfolded human. Indiscriminately begged from both equally, no understanding 1 cannot see.
Can chimps appreciate what others see?
Possess and learn rules about visual perception.
BUT: These rules do not necessarily incorporate notion seeing “about” something. E.g. cannot distinguish begging from blindfolded vs non-blindfolded person
Outline Pavinelli and Eddy 1996 3 explanations for chimps perceptual understanding
- General delay in psychological development in chimps
- Chimps may possess different (mentalistic) theory of attention (focus body and face)
- Subjective understanding visual perception may be unique to humans
Kaminski et al 2004 positive evidence understanding perception
1 person sat in front chimp with food. Chimps begged more when they were being watched (facing front with eyes open). No difference eyes closed vs open. Body facing correct way but face not = begged less.
Sensitive both body and face orientation but not eyes (explain negative findings)
Why is Kaminski et als positive evidence better than negative evidence?
Positive experiment: only 1 experimenter, task is easier. 2 experimenters = reduction attention. Too cognitively demanding.
Hare, Call and Tomasello 2001 study understanding knowledge and perception: positive evidence.
Competitive paradigm. Alongside another chimp. Subordinate and dominate chimp. Manipulated dominate chimps perception of food being hidden. Food placed in atrium where it couldn’t be seen by dominate chimp. Subordinate chimp only went for food when dominate chimp could not see where food was hidden.
What does Hare, Call and Tomasello 2001 study tell us about chimps understanding?
Chimps can reason about others’ knowledge on basis of what others have/have not seen.
Hare et al 2006 study on understanding perception and knowledge. Positive evidence.
Chimps show visual and auditory perspective taking. Chimp interacting with human with food on either side her. Whether chimp go for food faced away from attending person, or in line of sight. Approaches food competitor can’t see. Thinking about face not just body - by choosing food nearer her chest than eye-sight.
Baseline preference transparent = can see food. Override this for experiment.
Melis, Call and Tomasello 2006 auditory perspective taking study
Chimps preferred reach through silent rather than noisy tunnel. Consider what experimenter can hear, and their resulting behaviour.
Non-social control just likely go through loud and silent door.
Manipulate auditory perception of competitor.
What does Call and Tomasello 2008 study tell us about behavioural abstraction hypothesis?
Chimps do this without past experience these situations. No rule learned.
Contradicts Pavinelli’s behavioural abstraction hypothesis.
Outline Call and Tomasello 1999 study on understanding FB
Man watches as treat hidden under 1 of 2 cups, Chimp cannot see. Man leaves and cups are swapped. Man returns and points to 1 cup. Chimp has single change retrieve. Chimp scores looks under cup man didn’t point to. No apes passed. No evidence FB understanding. BUT high task demands.
Outline Marticorena et al 2011 study test 1 on FB
Opportunistically sampled. Violation of expectation method. 1. Experimenter moving conveyor belt. Actor can see what is happening so have correct reality. Unexpected when she looks in wrong box. look for longer when actors fails look correct location.
Outline Marticorena et al 2011 study test 2 on FB
Experimenter looked away so didn’t notice change object location. Monkey no expectations, understood she was ignorant.
Represent whether actor is knowledgeable or ignorant. But not of their own beliefs.
In contrast to 15-month olds
Outline Krupenye et al 2016 study on FB
Eye-tracking. Anticipatory gaze paradigm. Anticipate where chimp/human look for object. Significant first looks higher towards target than distractor. First look = anticipating where person look.
great apes anticipate other individuals will act according to FB.
What does Krupenye et al 2016 study on FB study tell us?
Competing explanation: apes used knowledge of abstract rules. Specifically that people tend look for objects in place they last saw them.
Do apes have ToM?
Reports of mentalising in wild (ancedotes)
Evidence understand: goals/intentions and seeing=knowing
BUT: Failure solve FB tasks until 2016
Mixed evidence: difference competition vs cooperation
Different ways interpret results.
