Lifespan development explores how we change and grow from conception to death. They view development as a lifelong process that can be studied scientifically across three developmental domains: physical, cognitive development, and psychosocial.

There are several theories of development that focus on the following issues: whether development is continuous or discontinuous, whether development follows one course or many, and the relative influence of nature… Eric Erikson modified Freud’s ideas and suggested a theory of psychosocial development.

cognitive development — domain of lifespan development that examines learning, attention, memory, language, thinking, reasoning, and creativity. psychosocial development — domain of lifespan development that examines emotions, personality, and social relationships. conception — when a sperm fertilizes an egg and forms a zygote. conservation — idea that even if you change the appearance of something, it is still equal in size, volume, or number as long as nothing is added or removed.