Object permanence is the understanding that even though an object has disappeared from view, that disappearance is probably temporary: the object has not disappeared totally from existence. Infants do not achieve this understanding until around eight months of age. Because of this, the baby girl likely believes her father no longer exists when he disappears from view, which is upsetting.

Piaget's stages of cognitive development are as follows: sensorimotor, preoperational, concrete operational and formal operational. Piaget associated an age ranges for each stag that specific developmental phenomena occur at. Preoperational stage occurs at the preschool age. At around 2 to 4 years of age, children Piaget theorized that children experience egocentrism. During this time, children have difficulty perceiving things from another's point of view. For example, a 3-year-old girl may cover her eyes with the intention of making herself invisible from her parents. As a result of her obstructed vision, she incorrectly assumes that her parents cannot see her.

Piaget says every human goes through a variety of stages in our cognitive development in a fixed way. The correct order is sensorimotor (0-18 months), preoperational (2-6 years), concrete operational (6-12 years), and formal operational (12-adult).

Children during middle childhood (typically between the ages of 7-11) are limited in their cognitive abilities. Although they perform well when problems or questions are presented in concrete terms (i.e., shape, size, color), they perform poorly on tasks that require them to think beyond the concrete, processing at a more abstract level. Claudia would be classified in the concrete operational stage.

The other stages of Piaget's cognitive development theory are outlined below:

Sensorimotor stage (0-2 years): Children learn about their world through their explorations, using sensory and motor functions.

Preoperational stage (2-6): Children begin to acquire language and represent symbols.

Formal Operational stage (12+): Adolescents can engage in deductive and inductive reasoning.

Adolescents think they have an imaginary audience when they believe that everyone is paying attention to them.

Another limitation of their cognition is personal fable, meaning that they have this unrealistic opionion of themselves.

Adolescents tend to engage in idealistic thinking, in which they ask "What if" questions, creating a utopia as opposed to a realistic view of the world.

Propositional thought is actually a cognitive advance during adolescence. They are able to accurately evaluate given verbal statements and rules, without needing to refer to real-world truths or objects.

Object permanence is defined as the understanding that objects continue to exist even if one cannot see them. According to Piaget, infants being to develop this at around 7-9 months of age in the sensorimotor stage.

The adolescent brain continues to develop into the early to mid twenties. In fact, the prefrontal cortex is the last brain region to fully develop, but it is primarily responsible for executive functions among other cognitive skills. This explains Jackie's inability to inhibit and think through long-term consequences of her actions.

In contrast to the behaviorist perspective of language acquisition championed by the like of B.F. Skinner, Chomsky argued that, because children can learn the rules of a language from incomplete evidence, that incomplete evidence must be supplemented by an innate linguistic capacity that all human beings are born with.

Individuals in late adulthood often have age-related memory difficulties; however, they often easily recall major life events from their adolescence and early adulthood years (e.g., graduation, marriage, college, career, etc.). They tend to reminisce about these events and describe those more to those around them. Associative memory is the ability to link unrelated events or information together (i.e. faces with names). Prospective memory is remembering to complete tasks or events in the future. Last, time-based memory is fabricated and a distractor item.

Conservation refers to the ability to know that physical properties, like mass and volume, are the same even if the object is in a different form.