Lev Vygotsky

Vygotsky was born in Orsha, in the Russian Empire (today in Belarus) into a nonreligious Jewish family. He was influenced by his cousin, David Vygotsky.  In the mid-1920s, he worked at the Institute of Psychology and other educational, research, and clinical institutions in Moscow, Leningrad, and Khark where he extensively investigated ideas about cognitive development. He died in 1934, at the age of 37, in Moscow of tuberculosis.

Vygotsky investigated child development and how this was guided by the role of culture and interpersonal comunication. 

Vygotsky observed how higher mental functions developed historically within particular cultural groups, as well as individually through social interactions with significant people in a child's life, particularly parents, but also other adults. Through these interactions, a child came to learn the habits of mind of her/his culture, including speech patterns, written language, and other symbolic knowledge through which the child derives meaning and which affected a child's construction of her/his knowledge.  

Less known is Vygotsky's research on play, or children's games, as a psychological phenomenon and its role in the child's development. Through play the child develops abstract meaning separate from the objects in the world, which is a critical feature in the development of higher mental functions.