Less Is More Executive Function and Symbolic Representation in Preschool Children. Carlson, Davis, Leach. Psychological Science 2005

<Weird the paper is from 2005 – based on the quality of the typography in the PDF it looks like its from the 80s>

1. Examines an executive control task called “less is more” where 2 collections of desirable items of different amounts are presented, but pointing to the small collection presents the large collection, and pointing at the large collection presents the small collection
   1. Basically you have to do the opposite of what you want
2. For 3 year olds, switching to a more symbolic version of the task improved results “as a function of symbolic distancing”
3. “Development can be thought of as the progressive acquisition of knowledge or skills, but also enhanced inhibition of responses that mask these abilities (Diamond, 1990).”
4. In general, performance in EF tasks improves rapidly from ages 3-6.  They involve some sort of nontypical behavior – the marshmallow task would be an example of this.
   1. Indeed, children do better on this task when they are told to think of the marshmallow as a cloud instead of food
5. “A key requirement for successful inhibition is to direct attention away from the salient perceptual or representational features of a stimulus that tend to elicit a prepotent response. For example, in Day/Night (Gerstadt et al., 1994), seeing a picture of the sun activates an association with ‘day,’ which must be replaced by a subdominant response, ‘night’.”
6. There is a model that states that there is a “hot,” “go” part of the brain that develops first, and then comes a “cool,” “know” system
7. When explicitly told and tested about the rules of the game, all children were able to show that they understood the rules outlined (they were repeated up to 3 times if necessary)
8. The way they describe the results is weird.  They use the word “probability” where ratio or something else seems like it would be correct.  Either that or I am misunderstanding the paper
9. They also say results were bimodal, but I don’t see what they are talking about.
10. 4 year olds (but not 3 year olds) performed statistically significantly better than chance
11. Results show that initial responses were impulsive but later slowed, indicating that they considered options and learned outcomes
12. In the second study, a symbolic substitute was used (candy was replaced by stones).  This series of two experiments  were done one chimps and they did better with this second variant of the task
    1. Also with even more abstract representations (40 vs 100 dots, mouse vs elephant)
    2. Performance in the mouse-elephant task was significantly better than in the original task, but for all other designs differences were not significant
13. Children correctly recalled the rules at the end of the game 93-100% accuracy