Asked by researchers to sort objects by shape, most toddlers in a large study had no trouble doing so. When subsequen...

Katherine on February 13, 2019

Hi @amandapaige,

I’m happy to help. The passage describes a study in which toddlers were told to sort objects according to two different rules, first by shape and then by color. When asked to sort the objects by the second rule, the toddlers had trouble doing so and often resorted to following the old rule. The passage concludes that this phenomenon is due to “insufficient development of the prefrontal cortex,” which is essential for adapting to new rules and is slow to mature.

The questions asks you to choose the answer that is most supported by the information above. Let’s take a look at each answer choice in turn.

First, Answer A says that toddlers unable to sort by color have a less developed prefrontal cortex than other children of the same age. The passage says that all toddlers have insufficient development of the prefrontal cortex, not just some. Additionally, this undevelopment results in trouble adapting to new rules in general, not specifically to sorting object by color. The study described in the passage happened to use sorting by color as the new rule, but the prefrontal cortex is not directly related to sorting objects by color. Because this answer misstates the findings of the study, it is the incorrect choice.

Answer B says only adolescents and adults can solve problems that require adapting to new rules. While the passage does say that the prefrontal cortex continues to develop into adolescence, this answer choice is not supported by the information in the passage. The passage says toddlers “almost invariably” persisted in applying the first rule. The inclusion of the word “almost” suggests that some of the toddlers, or at least one, was able to follow the second rule as requested. Additionally, the passage says nothing about the ability of adolescents or adults to adapt to new rules. For these reasons, this answer is the incorrect choice.

Answer C, says certain behavior by toddlers may not be willfully disobedient. You are right, that no where in the passage is disobedience discussed. However, the passage describes a study in which toddlers had difficulty following the rules requested of them. At first glance, the explanation may be that the toddlers did not follow the rule because they were disobedient. However, the conclusion of the study was that this behavior is due to insufficient brain development, not willful disobedience. Although the passage does not mention disobedience explicitly, the content of the passage does support the statement expressed in Answer C. Remember this question does not ask for the “main point” of the passage and instead asks you to pick the answer most supported by the passage.

Answer D says the prefrontal cortex is more important than upbringing in causing the development of adaptive behavior. While the passage does describe how development of the prefrontal cortex is essential to functions like adapting to new rules, the passage says nothing about the relative importance of upbringing to this behavior. We have not way of knowing whether brain development is more or less important of a factor when compared to upbringing. Therefore, this answer is incorrect.

Finally, Answer E says that skill of adapting to new situations is “roughly proportional” to the development of the prefrontal cortex. The passage does not describe the exact relationship between the ability to adapt to new rules and the development of the prefrontal cortex. Perhaps development of the prefrontal cortex occurs at a much slower rate than the development of the ability to adapt to new rules. We do not know that they are directly proportional, only that they are related. Therefore, this answer is incorrect as well.

I hope this is helpful. Please let us know if you have other questions!