AP Psychology Development Timeline

  • Birth

    Physical development
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    Sensorimotor stage (birth to 2 years)

    During this stage, children take in the world through sensory impressions and motor activities and develop object permanence.
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    Trust vs. Mistrust

    A child, well – cared for, nurtured, and loved, develops trust and security and a basic optimism. Badly cared for, he/she becomes insecure and mistrustful.
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    Preconventional morality

    Morality focuses more on self-interest: they obey rules either to avoid punishment or to gain concrete rewards.
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    Secure attachment

    Seen in 60% of children, a secure attachment between the infant and mother means that the child is comfortable and exploratory in a new environment, distressed when the mother leaves, and comforted when she returns.
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    Insecure attachment

    Infants who show insecure attachment will cling to their mother and not explore their surroundings, and will either cry loudly and remain upset or seem indifferent to her departure and return. Includes anxious-ambivalent and anxious/avoidant.
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    Easy babies

    Easy babies are cheerful, relaxed, and predictable in their feeding and eating habits.
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    Difficult babies

    Diffcult babies are irritable, negative, not adaptable, intense, and unpredictable or irregular.
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    Slow-to-warm-up babies

    Slow-to-warm-up babies are initially withdrawn and slow to adapt but later may "warm up". They tend to resist new people and situations.
  • Raise head to 45 degrees (2 months)

    Physical and motor development
  • Roll over (2.8 months)

    Physical and motor development
  • Sit with support (4 months)

    Physical and motor development
  • Sit without support (5.5 months)

    Physical and motor development
  • Pull self to standing position (7.6 months)

    Physical and motor development
  • Walk holding onto furniture (9.2 months)

    Physical and motor development
  • Creep (10 months)

    Physical and motor development
  • Stand alone (11.5 months)

    Physical and motor development
  • Walk (12.1 months)

    Physical and motor development
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    Preoperational stage (from age 2 until 6 or 7 years old)

    During this stage, the child is too young to perform mental operations and lacks the concept of conservation. Other key aspects include animism, egocentrism, and the development of a theory of mind.
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    Autonomy vs. Shame

    A "well - parented" child emerges from this stage sure of self, elated with his/her new-found control, and proud rather than ashamed.
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    Initiative Versus Guilt

    During these years, the healthily-developing child learns: (1) to imagine, to broaden skills through active play of all sorts, including fantasy (2) to cooperate with others (3) to lead as well as to follow. The negative outcome occurs when, immobilized by guilt, the child is: (1) fearful (2) hangs on the fringes of groups (3) continues to depend unduly on adults and (4) and is restricted both in the development of play skills and in imagination.
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    Industry Versus Inferiority

    Erikson believes that the fourth psychosocial crisis is handled, for better or worse, during what he calls the "school age," presumably up to and possibly including some of junior high school. The child who, because of successive and successful resolutions of earlier psychosocial crisis, is trusting, autonomous, and full of initiative will learn easily enough to be industrious and emerge with a sense of competence and high self-esteem. However, the mistrusting child will doubt the future.
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    Concrete Operational (6 or 7 to about age 12)

    At this stage of coginitive development, children understand conservation and fully gain the mental ability to comprehend mathematical transformations.
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    Conventional morality

    Morality focuses on caring for others and on upholding laws and social rules, simply because they are the laws and rules.
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    Puberty

    Puberty results in the growth of both primary sex characteristics and secondary sex characteristics. Primary includes development of reproductive organs and external genitalia. Secondary includes female breasts and hips, male deepened voice, and hair growth.
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    Formal Operational (12 years on)

    During this cognitive stage, the person understands abstract thinking and systematic thinking, which allows them to solve hypothetical problems and deduce consequences.
  • Menarche

    Average age: within a year of 12.5
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    Identity Versus Identity Diffusion

    During adolescence, from about 13 or 14 to about 20, the adolescent, learns how to answer satisfactorily and happily the question of "Who am I?" Erikson believes that during successful early adolescence, mature time perspective is developed; the young person acquires self-certainty as opposed to self-consciousness and self doubt.
  • Spermarche

    Average age: by age 14
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    Postconventional morality

    Actions are judged "right" because they flow from people's rights or from self-defined, basic ethical principles.
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    Intimacy vs. Isolation

    The successful young adult, for the first time, can experience true intimacy - the sort of intimacy that makes possible good marriage or a genuine and enduring friendship.
  • Average age of first child in US = 25

  • Average age women in US marry = 26

  • Average age men in US marry = 28

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    Generativity vs. Self-absorbtion

    In adulthood, the psychosocial crisis demands generativity, both in the sense of marriage and parenthood, and in the sense of working productively and creatively.
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    Sensory abilities

    Visual sharpness diminishes, and distance perception and adaptation to changes in light level are less acute. Reaction time, vision, sense of smell, and hearing diminish. A 65 year old sees a third less light than a 20 year old.
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    Physical changes during middle adulthood

    Physical decline gradually accelerates and fertility also decreases with menopause in women and a decline in sperm count and testosterone levels in men.
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    Cognitive changes during adulthood

    Neural processing slows during adulthood, meaning people take longer to react and solve problems. Crystallized intellgence, our accumulated knowledge and vocabulary, increases with age while fluid intelligence, the ability to reason speedily and abstractly, decreases. Memory begins to atrophy, but when a substantial loss of brain cells results in mental disintegration it results in dementia. Alzheimer's disease causes mental erosion that destroys memory and reasoning, and mental awareness.
  • Average age of midlife transition = 45

    During the midlife transition, an adult transitions to middle adulthood and realizes that their life will soon be mostly behind instead of ahead of them. For some, this is a time of struggle, regret, and feeling struck down by life.
  • Menopause

    Menopause is the end of a woman's menstrual cycle and their ability to reproduce, which occurs around age 50.
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    Integrity Versus Despair

    He can be intimate without strain, guilt, regret, or lack of realism; and he is proud of what he creates - his children, his work, or his hobbies.If one or more of the earlier psychosocial crises have not been resolved, he may view himself and his life with disgust and despair.
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    Physical changes during late adulthood

    Older adults are less likely to suffer from short-term illnesses, like cold and flu, because their immune system is more experienced. They are however more susceptible to life-threatening ailments, like cancer and pneumonia. Sensory abilities decrease, and our cells no longer replace themselves perfectly. General physical and cognitive degeneration results.
  • Average life expectancy for men in US = 84.3

  • Average life expectancy for women in US = 86.6