1. UNIT 9:
Developmental
Psychology

2. Developmental Psychology: branch of psychology which studies physical, cognitive and social changes through the life span.
Issue
Details
Nature/Nurture
How do genetic inheritance (our nature) and experience (the nurture we receive) influence our behavior?
Continuity/Stages
Is development a gradual, continuous process or a sequence of separate stages?
Stability/Change
Do our early personality traits persist through life, or do we become different persons as we age.

3. Prenatal Development and the Newborn
How, over time, did we come to be who we are? From zygote to birth, development progresses in an orderly, though fragile, sequence.
Preview Question 1: How does life develop before birth?

4. Conception
A single sperm cell (male) penetrates the outer coating of the egg (female) and fuses to form one fertilized cell, or zygote.

5. Prenatal Development
A zygote is a fertilized egg with 100 cells that become increasingly diverse. At about 14 days the zygote turns into an embryo (a and b).

6. At 9 weeks, an embryo turns into a fetus (c and d).
Prenatal Development
At 9 weeks, an embryo turns into a fetus (c and d).

7. Teratogens
Teratogens are chemicals or viruses that can enter the placenta and harm the developing fetus.
Fetal Alcohol Syndrome (FAS)
HIV
Drug Use

8. The Competent Newborn
Infants are born with reflexes that aid in survival.
Rooting Reflex: when a newborn’s cheek is touched s/he will turn head toward touch and begin sucking.
Helps them locate food.
Disappears around 3-4 months.
Preview Question 2: What are some of the newborn’s abilities, and how do researchers explore infants’ mental abilities?

9. The Competent Newborn
Offspring cries are important signals for parents to provide nourishment. In animals and humans such cries are quickly attended to and relieved.
Carl and Ann Purcell/ Corbis
Lightscapes, Inc. Corbis

10. Figure 11.3: Cross-cultural comparisons of infant mortality.
Infant mortality is the death rate per 1000 births during the first year of life. Although the United States takes pride in its modern, sophisticated medical system, it ranks only 20th in the prevention of infant mortality. One of the main factors underlying this poor showing appears to be low-income mothers’ limited access to medical care during pregnancy. (Data from U.S. Census Bureau, International database)
Fig. 11-3, p. 422

11. Infancy and Childhood
Infancy and childhood span from birth to the teenage years. During these years, the individual grows physically, cognitively, and socially.
Stage
Span
Infancy
Newborn to toddler
Childhood
Toddler to teenager

12. Human Cerebral Cortex Sections
Developing Brain
At birth, most brain cells are present. After birth, the neural networks multiply resulting in increased physical and mental abilities. Infant’s psychological development depends on biological development.
Human Cerebral Cortex Sections

13. Maturation
The development of the brain unfolds based on genetic instructions, causing various bodily and mental functions to occur in sequence— standing before walking, babbling before talking—this is called maturation. Maturation sets the basic course of development, while experience adjusts it.
Changes at various points include:
Neural networks in an infants brain
Body & body chemistry in women – into and out of child bearing years.

14. Motor Development
First, infants begin to roll over. Next, they sit unsupported, crawl, and finally walk. Experience has little effect on this sequence.
Renee Altier for Worth Publishers
Phototake Inc./ Alamy Images
Profimedia.CZ s.r.o./ Alamy
Jim Craigmyle/ Corbis

15. Fig. 11-5, p. 425 Figure 11.5: Landmarks in motor development.
The left edge, interior mark, and right edge of each bar indicate the age at which 25%, 50%, and 90% of infants (in North America) have mastered each motor skill shown. Developmental norms typically report only the median age of mastery (the interior mark), which can be misleading in light of the variability in age of mastery apparent in this chart.
Fig. 11-5, p. 425

17. Maturation
Maturation sets the course for development, while experience adjusts it.
Maturation is sometimes referred to as physiological “ripening”, especially of the nervous system.
Once maturation has begun, we can participate in experiences which contribute to our psychological development and further our physical development.

18. Infants do show evidence of memory.
Infant Memory
The earliest age of conscious memory is around 3½ years (Bauer, 2002).
Infantile amnesia: related to language development.
As we develop language, the way in which we organize memories change.
A 5-year-old has a sense of self and an increased long-term memory, thus organization of memory is different from 3-4 years.
Infants do show evidence of memory.

19. Cognitive Development
Piaget believed that the driving force behind intellectual development is our biological development amidst experiences with the environment. Our cognitive development is shaped by the errors we make.
He believed that at certain stages in childhood we acquire cognitive abilities.
The advancements are the result of biological development amidst experiences with the environment.
Preview Question 4: From the perspective of Piaget and of today’s researchers, how does a child’s mind develop?
Both photos: Courtesy of Judy DeLoache

20. Piaget’s Stage Theory Fig. 11-12, p. 433
Figure 11.12: Piaget’s stage theory.
Piaget’s theory of cognitive development identifies four stages marked by fundamentally different modes of thinking through which youngsters evolve. The approximate age norms and some key characteristics of thought at each stage are summarized here.
Piaget’s Stage Theory
Fig , p. 433

21. Schemas are mental molds into which we pour our experiences.
Piaget used the concept of schema, assimilation and accommodation to explain how we learn from our environment.
Schemas are mental molds into which we pour our experiences.

22. Assimilation and Accommodation
The process of assimilation involves incorporating new experiences into our current understanding (schema). The process of adjusting a schema and modifying it is called accommodation.
Bill Anderson/ Photo Researchers, Inc.
Jean Piaget with a subject

23. Schema, Assimilation & Accommodation

24. Piaget’s Theory and Current Thinking

25. Sensorimotor Stage
In the sensorimotor stage, babies take in the world by looking, hearing, touching, mouthing, and grasping. Children younger than 6 months of age do not grasp object permanence, i.e., objects that are out of sight are also out of mind.
Doug Goodman

26. Stranger Anxiety (Sensorimotor Anxiety)
At about 8 months infants for m schemas for familiar faces and cannot assimilate new faces.
Last from about 8 to 24 months.

27. Sensorimotor Stage: Criticisms
Piaget believed children in the sensorimotor stage could not think —they do not have any abstract concepts or ideas.
However, recent research shows that children in the sensorimotor stage can think and count.
Children understand the basic laws of physics. They are amazed at how a ball can stop in midair or disappear.

28. Sensorimotor Stage: Criticisms
2. Children can also count. Wynn (1992, 2000) showed that children stared longer at the wrong number of objects than the right ones.

29. Ontario Science Center
Preoperational Stage
Piaget suggested that from 2 years old to about 6-7 years old, children are in the preoperational stage—too young to perform mental operations.
Ontario Science Center

30. Preoperational Stage: Criticism
DeLoache (1987) showed that children as young as 3 years of age are able to use metal operations. When shown a model of a dog’s hiding place behind the couch, a 2½-year-old could not locate the stuffed dog in an actual room, but the 3-year-old did.

31. Egocentrism
Piaget concluded that preschool children are egocentric. They cannot perceive things from another’s point of view.
When asked to show her picture to mommy, 2-year-old Gabriella holds the picture facing her own eyes, believing that her mother can see it through her eyes.

32. Theory of Mind
Preschoolers, although still egocentric, develop the ability to understand another’s mental state when they begin forming a theory of mind. Theory of mind is the ability to attribute mental states – beliefs, intents, desires – to others and to understand that others have beliefs, intents and desires that are different from one’s own.

33. Concrete Operational Stage
In concrete operational stage, given concrete materials, 6- to 7-year-olds grasp conservation problems and mentally pour liquids back and forth into glasses of different shapes conserving their quantities.
Children in this stage are also able to transform mathematical functions. So, if = 12, then a transformation, 12 – 4 = 8, is also easily doable.

34. Fig. 11-14, p. 435 Figure 11.14: The gradual mastery of conservation.
Children master conservation during the concrete operational period, but their mastery is gradual. As outlined here, children usually master the conservation of number at age 6 or 7, but they may not understand the conservation of area until age 8 or 9.
Fig , p. 435

35. Formal Operational Stage
Around age 12, our reasoning ability expands from concrete thinking to abstract thinking. We can now use symbols and imagined realities to systematically reason. Piaget called this formal operational thinking.

36. Formal Operational Stage
Rudiments of such thinking begin earlier (age 7) than what Piaget suggested, since 7-year-olds can solve the problem below (Suppes, 1982).
If John is in school, Mary is in school. John is in school. What can you say about Mary?

37. Reflecting on Piaget’s Theory
Piaget’s stage theory has been influential globally, validating a number of ideas regarding growth and development in many cultures and societies. However, today’s researchers believe the following:
Development is a continuous process.
Children express their mental abilities and operations at an earlier age.
Formal logic is a smaller part of cognition.