Major Characteristics and Developmental Changes:

• Infants knows the world through their movements and sensations

• Infants learn that things continue to exist even when they are out of sight (object permanence), however this concept is not fully developed yet. 

• Infants know their parents well, objects to new people, and seems very worried when the parent leaves. This is because the infant does not understand that the parent will return. However infants who have had successful separations from the parents followed by their return (such as hours spent in childcare) begin to understand that the missing parent will return. 

• As they reach two years old, they become more curious and would place objects in their mouth as they explore the quality and uses.

Major Characteristics and Developmental Changes:

• Children begin to use more words. Vocabulary and comprehension increases. 

• Children tend to be egocentric and struggle to see things from the perspective of others. They only see things from their point of view.

• Children rely on transductive reasoning ( drawing conclusions from one general fact to another). For example, when a child disobeys a parent and then falls down the same day, the child may ascribe the fall to bad behaviour. 

• Child also think in concrete terms -  that they may take words literally. For example, if someone tells them to break a leg, they may wonder why they should snap their leg bones in two. 

• Children will engage in more pretend play and will use symbols or toys to represent other things.  Their imagination begins to go wild and they really spend a lot of time playing. 

Major Characteristics and Developmental Changes

• During this stage, children begin to thinking more logically. Children begin to use primitive reasoning and want to know the answers to all sorts of questions  

• They begin to understand the concept of conservation; that the amount of liquid in a short, wide cup is equal to that in a tall, skinny glass, for example.

• Children will begin to see other people as independent objects, and they’ll also begin to see themselves in relation to those other people.  For example, they start to understand relationships i.e. teacher-student.

Major Characteristics and Developmental Changes:

• At this stage, the adolescent or young adult begins to think abstractly and reason about hypothetical problems

•  They can become goal-oriented, meaning that they can envision things like world peace or or they start to contemplate the meaning of life.  For instance, in earlier stages children may use things like trial-and-error to  figure things out. But in this stage, they can really think about these processes to be more efficient and to yield higher level results from whatever task they’re doing. 

• The adolescent begin to think more about moral, philosophical, ethical, social, and political issues that require theoretical and abstract reasoning