quality:corruption
Individual

Besides the development of mind in general in the course of history, there is also the development of individual human minds. Some of the individual changes vary from person to person as a form of learning from experience, like forming specific memories or acquiring particular behavioral patterns. Others are more universal developments as psychological stages that all or most humans go through as they pass through early childhood, adolescence, adulthood, and old age. These developments cover various areas, including intellectual, sensorimotor, linguistic, emotional, social, and moral developments. Some factors affect the development of mind before birth, such as nutrition, maternal stress, and exposure to harmful substances like alcohol during pregnancy.

Early childhood is marked by rapid developments as infants learn voluntary control over their bodies and interact with their environment on a basic level. Typically after about one year, this covers abilities like walking, recognizing familiar faces, and producing individual words. On the emotional and social levels, they develop attachments with their primary caretakers and express emotions ranging from joy to anger, fear, and surprise. An influential theory by Jean Piaget divides the cognitive development of children into four stages. The sensorimotor stage from birth until two years is concerned with sensory impressions and motor activities while learning that objects remain in existence even when not observed. In the preoperational stage until seven years, children learn to interpret and use symbols in an intuitive manner. They start employing logical reasoning to physical objects in the concrete operational stage until eleven years and extend this capacity in the following formal operational stage to abstract ideas as well as probabilities and possibilities. Other important processes shaping the mind in this period are socialization and enculturation, at first through primary caretakers and later through peers and the schooling system.

Psychological changes during adolescence are provoked both by physiological changes and being confronted with a different social situation and new expectations from others. An important factor in this period is change to the self-concept, which can take the form of an identity crisis. This process often involves developing individuality and independence from parents while at the same time seeking closeness and conformity with friends and peers. Further developments in this period include improvements to the reasoning ability and the formation of a principled moral viewpoint.

The mind also changes during adulthood but in a less rapid and pronounced manner. Reasoning and problem-solving skills improve during early and middle adulthood. Some people experience the mid-life transition as a midlife crisis involving an inner conflict about personal identity, often associated with anxiety, a sense of lack of accomplishments in life, and an awareness of mortality. Intellectual faculties tend to decline in later adulthood, specifically the ability to learn complex unfamiliar tasks and later also the ability to remember, while people tend to become more inward-looking and cautious.