Children recognize facial expressions associated with emotions at an early age—at
least by the age of 2 years—and some investigators have suggested that infants as
young as 10 weeks evidence some form of comprehension of emotion from facial
expressions (Izard & Harris, 1995).
Regarding the causes (and effects) of emotion and the cues used in inferring emotion,
developmental research has detailed a progression from situation-bound,
“behavioral” explanations of emotion to broader, more mentalistic understandings.
In other words, a child’s early understanding of emotion is based on her theory that
the world causes her feelings: “I am mad because someone broke the toy.” As she
develops, her explanations of emotions move inward, focusing on internal causes:
“I am mad because that broken toy was important to me,” or, “I am mad because I
thought the person who broke my toy was my friend.”