Acquiring a Acquiring a theory of mindtheory of mindTypically developing children Typically developing children

and adultsand adults

Unexpected transfer testWimmer & Perner (1983)

While Maxi is out playing, his Mum takes the chocolate from the cupboard and grates some of it into a cake.

Maxi is returning from play feeling hungry. He wants his chocolate.

Where will Maxi look for his chocolate?

Where did Maxi put his chocolate?

Where did Mum put his chocolate?

Deceptive box test

What’s inside this tube?

What is it?

What will your friend Johnny say is inside? (Perner et al, 1987)

When you first saw this tube, before we opened it, what did you think was inside? (Gopnik & Astington, 1988)

Appearance-realityAnd correlations between theory of mind tests

Flavell et al (1983) Gopnik & Astington (1988)

Have children been underestimated? Perhaps they misunderstand what the

experimenter is asking

Difficulty with the test question (Siegal & Beattie, 1991)

The importance of story comprehension (Lewis et al, 1994)

The importance of state-change (Wimmer & Hartl, 1991)

What’s inside this tube?

What is it?

I’ve taken away the Smarties and put a pencil in the tube

When you first saw this tube, before we opened it, what did you think was inside?

Wimmer and Hartl got it wrongSaltmarsh et al (1995)

What’s inside this tube?

What is it?

I’ve taken away the Smarties and put a pencil in the tube

When you first saw this tube, before we opened it, what did you think was inside?

When you first saw this tube, before we opened it, what was inside?

Explaining children’s correct judgments in state change Mitchell & Lacohee (1991)

What’s inside this tube?

Can you post a picture of what you think’s inside the tube…

What is it?

When you posted your picture, what did you think was inside this tube?

• Cartoon posting control condition

The truth about false The truth about false belief!belief!

Wellman et al’s (2001) meta Wellman et al’s (2001) meta analysisanalysis

Modified test

Standard test

Age

Perform

ance

If there was no shift

Age

Perform

ance

If there was a shift

Age

Perform

ance

If there was a shift and modifications merely boosted performance

Age

Perform

ance

If there was a shift

Age

Perform

ance

If there was a shift

Adult’s difficulty with false Adult’s difficulty with false beliefbelief

Mitchell et al, 1996Mitchell et al, 1996

Hindsight biasHindsight biasFischhoff, 1975Fischhoff, 1975

Who was most likely to win a battle fought in Who was most likely to win a battle fought in India 200 years ago, British or Ghurkhas?India 200 years ago, British or Ghurkhas?

The British had good tactics and good The British had good tactics and good weaponsweapons

The Ghurkhas knew the terrain and had great The Ghurkhas knew the terrain and had great determinationdetermination

Actually, the British won but put that out of Actually, the British won but put that out of your mind because I want to know who you your mind because I want to know who you thought had the best chance of winning given thought had the best chance of winning given the factors that advantaged one side or the the factors that advantaged one side or the otherother

Result: Hindsight bias and confusion between Result: Hindsight bias and confusion between own and others’ beliefsown and others’ beliefs

Keysar et al (2003)

Apperly et al (2006)

Psychological Science