childrens understanding and perception of ambiguous figures?

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Children’s Understanding and Perception of Ambiguous Figures?

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Page 1: Childrens Understanding and Perception of Ambiguous Figures?

Children’s Understanding and Perception of Ambiguous Figures?

Page 2: Childrens Understanding and Perception of Ambiguous Figures?

Learning Objectives

Explain what an ambiguous figure is and give examples of different types.

Explain the two major theories of perceptual reversal and assess the relative contributions of each.

Discuss how the ability to experience perceptual reversals may/or may not be related to an ability to understand multiple representations.

Discuss implications of Gopnik’s findings (both papers) for atypical populations such as autism.

Page 3: Childrens Understanding and Perception of Ambiguous Figures?

What are ambiguous figures?Content Perspective Figure-ground

Page 4: Childrens Understanding and Perception of Ambiguous Figures?

Why do ambiguous figures reverse?

Neural Satiation- Fatiguing of the neural process responsible for one perception leads to its end, and then the process for the alternative representation occurs.

Top-down knowledge-The person’s knowledge of the two alternative percepts and their knowledge of the reversibility of the figure cause reversals.

Page 5: Childrens Understanding and Perception of Ambiguous Figures?

Successive colour contrast

Page 6: Childrens Understanding and Perception of Ambiguous Figures?

Support for Bottom-up theories

Studies using selective–adaptation paradigm

Number of reversals reported increases over a time period of continuous viewing

Page 7: Childrens Understanding and Perception of Ambiguous Figures?

Selective–adaptation paradigm(Long, Toppino, Mondin, 1992)

Page 8: Childrens Understanding and Perception of Ambiguous Figures?

Relationship between time and reversals reported (Toppino & Long, 1987)

Page 9: Childrens Understanding and Perception of Ambiguous Figures?

Support for Top-down theories

Number of reversals reported are affected by the instructions given

Uninformed subjects fail to reverse ambiguous figures

Page 10: Childrens Understanding and Perception of Ambiguous Figures?

Instructions affect perception(Seth & Reddy,1979; Liebert & Burk, 1985)

Page 11: Childrens Understanding and Perception of Ambiguous Figures?

Failure to reverse ambiguous figures by uninformed subjects. (Rock and Mitchener, 1992)

Page 12: Childrens Understanding and Perception of Ambiguous Figures?

Do young children reverse ambiguous figures?

Procedure

-Report on initial perceptions

-Informing children of alternative perception

-Report on perception once informed

Page 13: Childrens Understanding and Perception of Ambiguous Figures?

Summary of findings

Rock, Gopnik, & Hall 1994

1.) Found 3-4 year olds had difficulty reversing ambiguous figures even when informed

2.) The number of spontaneous reversals tends to increase with age.

Page 14: Childrens Understanding and Perception of Ambiguous Figures?

Follow-up study (Gopnik and Rosati, 2001)

1.) When does the ability to perceive reversals develop?

2.) How does the ability to perceive reversals relate to more abstract knowledge about multiple representations?

Page 15: Childrens Understanding and Perception of Ambiguous Figures?

Gopnik and Rosati (2001) argue:

Ambiguous figures involve multiple perceptual representations of the same object .

Research has demonstrated that understanding multiple representations is quite difficult for young children.

Page 16: Childrens Understanding and Perception of Ambiguous Figures?

Unexpected transfer test

Children under age 5 fail the Maxi task.

(Wimmer & Perner ,1983)

Page 17: Childrens Understanding and Perception of Ambiguous Figures?

Deceptive box test

Between ages 3-5 children begin to understand different people hold different beliefs, and that their own beliefs may change. (Gopnik and Astington, 1988)

Page 18: Childrens Understanding and Perception of Ambiguous Figures?

Droodle task

By age 6 children appreciate that someone who shares their same visual perspective may interpret information differently (Taylor, 1988).

Page 19: Childrens Understanding and Perception of Ambiguous Figures?

What is the relationship between perceiving ambiguous figures and understanding multiple representations?

Gopnik and Rosati (2001) 1.) The ability to experience reversals might

develop earlier than an abstract understanding of multiple representations

2.) The ability to perceive reversals might first require a more general understanding of multiple representations

(Top-down explanation)

Page 20: Childrens Understanding and Perception of Ambiguous Figures?

Method

Tested 29 (3-5 year olds) Tasks

- false belief task

- droodle task

- ambiguous figures

Page 21: Childrens Understanding and Perception of Ambiguous Figures?

Findings

Children only report reversals at about 5 years of age.

Children only reported reversals if they had passed false belief tasks.

Children’s performance on the droodle task was correlated with their experiencing reversals.

Page 22: Childrens Understanding and Perception of Ambiguous Figures?

Conclusion

Supports Top-down explanation The immediate experience of perceptual

reversals may rely on a broader understanding of multiple representations (ambiguity).

Page 23: Childrens Understanding and Perception of Ambiguous Figures?

Implications of Gopnik and Rosati’s findings for Autism Triad of Impairments (Wing and Gould, 1979)

Socialisation, communication, and imagination.

TOM Hypothesis of Autism Baron-Cohen, Leslie and Frith (1985)

- Individuals with autism fail False-belief

Page 24: Childrens Understanding and Perception of Ambiguous Figures?

Ropar, Mitchell, Ackroyd (2003)Rationale:

If individuals with autism have difficulties passing False-belief and Droodle tasks (TOM tasks)

And TOM tasks and AF tasks rely on understanding same underlying concept

Then individuals with autism who fail TOM tasks will have difficulty on AF task

Aim: Present individuals with autism with False-belief,

Droodle, & AF tasks

Page 25: Childrens Understanding and Perception of Ambiguous Figures?

Criticisms of Gopnik and Rosati’s Method Unreliability of verbal reports of perceptions-failure to report when see reversal-reporting they see reversal when they don’t

15 of 21 in Gopnik & Rosati’s needed prompting by experimenter pointing to features

- leads us to focus on ability to identify alternative rather than report reversals

Page 26: Childrens Understanding and Perception of Ambiguous Figures?

Ropar, Mitchell, & Ackroyd (2003)

Stimuli - simple, less familiar, head and tail at opposite ends

Subjects- 22 Autism, 25 MLD, 18 Typ. 7-8 yr olds

Page 27: Childrens Understanding and Perception of Ambiguous Figures?

Results

Group All FB q’s correct

Correct on Droodle

Saw both Alternatives on both AF

Autistic 4 5 16MLD 17 18 16

Sig (<.01) Sig (<.01) n.s.

FB=false belief

AF = Ambiguous figures

Provides evidence against Gopnik and Rosati’s claim that both TOM tests and reversing AF draw on the same underlying concept.

Page 28: Childrens Understanding and Perception of Ambiguous Figures?

Discussion Why then is AF easier for those with autism?

Perhaps the difficulty is not with switching to other representation but acknowledging their earlier interpretation (like Appearance-reality task)

However, AF differs as it requires one to interpret the same information in a different way, rather than revise their beliefs (like with App. Reality & TOM)

Conclusion: Handling revision of beliefs is difficult for children with autism, while forming multiple representations of a single stimulus is relatively easy.

Page 29: Childrens Understanding and Perception of Ambiguous Figures?

Discussion questions 1.) Which theory of perceiving AF do you agree with

more and why? (List and explain your reasons.) 2.) Do you agree or disagree with the following

statement: If a child can successfully reverse one type of AF

they should be able to reverse other types? (Explain your reasons for your stance); What would a Piagetian or rather a Domain general account of child development think? (List and explain your reasons.)

3.) Are reporting reversals and being able to acknowledge two representations the same thing?