The opposing field is the nurture enthusiast, another large group of scholars who believe that the source of a human personality is nurture, rather than inheritance. According to those scientists, a person is born with a blank slate of mind, and the various sources influence the development of a human personality, shaping its form throughout a person’s life. The most major sources of influence are prenatal and parental impact, although peer influence, the increasing role of medial, socio-economic conditions and marketing efforts are also known to be largely responsible for the shaping of a human personality.
Early childhood development most commonly refers to the time period between birth and schooling, at approximately age 4. Many people agree that this developmental period is "the most critical and the most vulnerable in any child's development. (Brazellon. "Our Window to The Future." Feb. 2003.) During this time period, many amazing milestones are reached. Every child goes through many phases in a short period of time. Stimulation is a very important part of brain development, which consists of anything that causes the brain to be used, through any of the senses. Without the stimulation, the brain has no opportunity to develop.