Developmental Psych

Readings

McAlister, A., & Peterson, C. (2007). A longitudinal study of child siblings and theory of mind development. Cognitive Development, 22(2), 258-270. doi: 10.1016/j.cogdev.2006.10.009

• Compared the relationship between children’s understanding of ToM and their number of child-aged siblings
• ToM: “[they] become aware that human behaviour is guided by mental states of belief, knowledge, memory and imagination that may conflict with overt reality.”
• False belief tasks were utilise, which require children to predict/explain people’s behaviour whose interpretations of the scenario are incorrect
• Goal: To “longitudinally investigate the possible link between ToM and the preschooler’s number of child-aged siblings using age appropriate batteries”
• They wanted to examine the possibilities of either:

• The sibling continually benefits the other’s growth of social understanding  from age 3 - 6 VS

• For this argument: Children are known to spend lots of time with their siblings in this period
• Child with more siblings has more opportunities to eavesdrop and intrude into conversations, to listen to arguments, to observe parents reasoning with siblings, to negotiate conflicts, to pretend, to cooperate.

• Whether the child is advantageous early in this period as opposed to later on

• For this argument: Children start interacting with other people outside of the family (e.g. friends), more concerned about popularity and peer acceptance - may replace sibling interaction with extra-familial pretend play, rule games, negotiation, deception and teasing

Experiment 1

• Children had a mean age of 5 years and 4 months
• Children were from middle class neighbourhoods
• English was first language
• Ranged from kids with no siblings to one’s with 3 siblings
• Required an understanding of “conflicting mental representations”
• Children had to perform representation tests - required to pretend that the carrort was a phone and has to engage with the carrot like a phone
• Child was then told to stop pretending, and then asked what really is this and what did they pretend it was
• The same was done with a potato - children had to pretend the potato was soap and then asked what it really is and what they were pretending it was
• Results suggest that only children were seriously disadvantaged in regards to ToM performance, and those with two or more siblings scored significantly higher.
• However, those with a single child-aged sibling did not differ significantly from only children or those with two or more siblings
• No significant effect for age

Experiment 2

• Children were 14 months older than when tested in experiment 1
• Children could only participate in this study if they had passed all the control questions on standard belief tests in experiment 1, and if their number of siblings had not altered
• More difficult than experiment 1 as the container was more misleading and children had to attribute an emotion to the protagonist
• In the experiment, a puppet who liked animal cookies was hidden while a clearly labelled box of these cookies were emptied and filled with rocks
• The puppet then returned and children were asked how the puppet was feeling before, and then how the puppet would feel after he opened the cookie box
• Another experiment (two appearance-reality test, AR) was conducted whereby children were given a fruit-shaped candle, and a ballpoint pen that looked like a carrot, banana or flower. Children were shown the real purpose of the objects (e.g. lit candle, wrote with pen), and then children had to identify what the object’s purpose really was, what does it look like
• Results suggest that only children were seriously disadvantaged in regards to ToM performance, and those with two or more siblings scored significantly higher.
• However, those with a single child-aged sibling did not differ significantly from only children or those with two or more siblings
• Results suggested that the number of child-aged siblings made a significant independent contribution

General Discussion

• Significant link between ToM performance and numbers of child-aged siblings
• Suggests that their is a continual benefit of having siblings from ages 3-6 as they continue to increase children’s ToM performance
• Children examined having parents who were mostly middle-class and well-educated and maybe if they were of lower socioeconomic status and poor education may not gain ToM benefits from siblings
• Only-children may be significantly deprived of exposure to false beliefs
• Parenting behaviours and techniques could also be a factor that influences children’s ToM performances

• Nelson, P. B., Adamson, L. B., & Bakeman, R. (2008). Toddlers' joint engagement experience facilitates preschoolers' acquisition of theory of mind. Developmental Science, 11(6), 847-852. doi: j.1467- 7687.2008.00733.x
• “Acquiring a theory of mind is fundamental to a child’s understanding the social world and to his or her ability to make sense of a predicts other’s actions
• The study focuses on examining joint engagement experiences with their mothers from 18 to 30 months and subsequent false belief understanding
• Child’s joint engagement - active sharing of an object or event with a social partner
• Coordinated joint engagement - Child explicitly focuses on the mother during periods of joint engagement
• Supported joint engagement- child primarily focuses on the shared object during periods of joint engagement
• In the study they also distinguished between non-symbol infused and symbol-infused joint engagement

• The formation and use of symbols (including words and symbolic gestures) can detract from the child’s attention from the immediate aspects of objects

• Suggests that joint engagement experience likely facilitates theory of mind development, and the more they engage in joint engagement, the more their false belief understanding will be broadened.
• Hypothesised that: the more time toddlers spend in coordinated joint engagement, the earlier they may succeed on false belief tasks as preschoolers

• Deeper understanding of the social partner’s nonverbal behaviour and their shared focus
• Allows the child to develop an understanding of others as intentional beings - a necessary precursor to theory of mind development

• AND it was hypothesised that the more time toddlers spent in symbol-infused joint engagement, the earlier they may succeed on false belief tasks as preschoolers

• Can provide children with opportunities to utilise symbols in shared activities, which can then facilitate the development of theory of mind

Method

• Longitudinal study of the development of joint engagement
• Children range from 18-66 months
• 4 role plays were performed with child serving as the star and the mother as the supporting actress (given cue cards and props to facilitate interaction

1. Non-symbol infused supported joint engagement - Child and mother actively involved with same object. Child does not explicitly ackbowledge mother
2. Non-symbol infused coordinated joint engagement- Involved with same object, child actively acknowledges the mother’s involvement
3. Symbol-Infused supported joint engagement - Involved with same object, child is responding to symbols, does not acknowledge mother
4. Symbol-Infused coordinated joint engagement - Involved with shame object, child is responding to symbols, acknowledge mother

• False belief tasks (‘changed location’ and ‘misleading container’) were performed at 43, 55 and 66 months - all children succeeded and therefore not included

General Discussion

• During coordinated joint engagement - child attend to a social partner as well as the object/event they were sharing

• Perner, J., Ruffman, T., & Leekam, S. R. (1994). Theory of mind is contagious: you catch it from your sibs. Child Development, 65(4), 1228-1238. doi: j.1467-8624.1994.tb00814.x

-       Investigated the relation between family size and ‘theory of mind.’

-       Tested whether the number of siblings does have a beneficial effect on the age at which children show an understanding of false belief.

-       Believes that in science, new theoretical insights do not merely ‘mature’ over time, but rather need hard work and devotion.