At what stage do infants typically begin to show signs of self-interest in play?

Infants typically begin to show signs of self-interest in play between 6 to 12 months of age. During this stage of development, children start to engage more actively with their environment and the objects around them. They are motivated by curiosity and begin to explore using their hands and mouths, which is essential for cognitive development.

As infants enter this stage, they also start to engage in more interactive play, such as shaking rattles or banging objects together, which reflects their growing understanding of cause and effect. This involvement indicates their increasing ability to focus on their own actions and interests, distinguishing it from earlier stages where play may be more reflexive or reactive rather than self-directed. This period also marks the beginning of parallel play, where infants may play alongside other children while still focusing on their individual activities, demonstrating early social engagement driven by self-interest.