1. What is a developmental theory? It describes what happens in the course of development: what changes and what stays the same (individuals, select subsets or groups, and  normative). Provides for a way of understanding why development takes the shape that it does. Allows for prediction (not precise, but based on probability), and allows for control of factors that are correlated with desired outcomes.

If we know what 'normal' behavior is like, we know what to expect  (prediction) of children at specific ages and can plan appropriately (control) for children's changing needs. Empirical knowledge about children's development can counter myths ('daycare is bad for children'), and theories based on empirical research (description and understanding) can  inform the design of school and child care programs as well as government and private services for children. Scientifically-based knowledge of child development enables us to be more successful in advocating for children's needs. 

As students of child development, theories guide our observations, framing our understanding of why children behave the way they do at the different points in their development. While no one theory can fully explain development, most researchers today take an eclectic approach, incorporating aspects of various theories into their work.

 We reviewed the methods used in  researching child development.

I mentioned the psychophysiological approach, and in addition to the methods listed last week, we added considered the aspects of sampling developmental changes over time. Obviously, one approach is to follow specific individuals over the course of their development. This is called the longitudinal approach, and while it shows the steps or stages or increments in change over time, it has several disadvantages. First, participants may become 'test-wise' over time. Also, over time, many participants may move away or drop out of the study. Longitudinal studies are more time-consuming and expensive to conduct. Finally, researcher may be contaminated by 'cohort effects', differences between groups of children born at different points in history. Development in a specific set of individuals of the same age may be influenced by environmental events or conditions that impact that particular cohort differently than from  an earlier or later group of children of the same ages. For example, if you were to study the 'normal' development of nightmares, children who were four when the events of 9/11 occurred may have very different dream behaviors than children whose dream development from age 4 on were first studied ten years ago. 

Cross-sectional studies  Look at the full range of ages being studied all at the same time. In other words, if you want to know about development between ages 8 to 12, you examine 8, 9, 10, 11 , and 12 years olds all at once and  draw conclusions based on differences between these age groups. This approach is less expensive, less time consuming and easier to carry out, but does not reveal much about individual differences in development, and is also likely to be contaminated by cohort effects. (Again, 9/11 might  have a distorting influence on a study of the normal development of nightmares...)

The longitudinal-sequential approach looks at 2 or more age groups over a shorter period of time than a purely longitudinal design. By simultaneously studying two groups, one age 8 and one age10 over 2 years time, you can get a four year picture of development that controls, to some degree, for cohort effects.

Microgenetic research gives a close-up look at individual developmental changes but is expensive and difficult to do .

Ethical considerations in doing research on children.
 Then we discussed the ethical concerns that needed to be addressed in doing research on children.  The overarching message to all researchers is first, 'Do no harm".  While research on adults has various methods for addressing ethical concerns, children are especially vulnerable and need even more stringent protection. With adults, researchers must obtain 'informed consent', in which the person understands all aspects of the procedures and agrees to participate. Meaningful 'consent' is not a realistic expectation for most children under the age of  7, and older children's understanding of the explanations of procedures and also of what 'consent' means will vary with age, experience, and maturity. Therefore,  parents must give 'informed consent'. Research participants have the right to withdraw from a study at any time. Even some adults have a hard time refusing to complete something they have previously agreed to do; children are not only in an unequal power relationship, they have been taught to respect and obey adults, and to look to them for guidance and protection; therefore they are far more vulnerable to coercion or the disapproval or disappointment of researchers. When research involves any kind of deception, 'debriefing' usually undoes any misunderstandings with adults, but may not work as well for children, who tend to take things more literally and are more deeply impacted by adults' deceptions. Researchers have the obligation to share the results of their work with their subjects (if they can understand) and their parents and to benefit , if relevant, from their participation. Of course, all researchers must ensure the protection of  people's privacy (confidentiality), their dignity and their basic human rights, but researchers who study children must, in addition, follow the principle of 'in loco parentis', acting 'in the place of the parents' by putting the best interests of the child ahead of their research interests.

1. Our understanding of childhood as a special period, unique in the development of a person, is relatively recent.  In western societies, up to a few hundred years ago, infants were regarded as a unique stage of complete dependency, but once they were no longer toddlers, they were regarded as minimally competent miniature adults: they were expected to conform to adult expectations and to contribute to the welfare of the household to the extent that they were able. If they lived on a farm they gradually took on more and more responsibilities; in all but wealthy families, children of non-farming families often had to go to work as and apprentice to a trade or to a job doing manual and menial labor. Even today in parts of the world, many children are at work tending cattle or younger siblings, weaving rugs,   chopping weeds in the fields, gathering wood, etc. In wealthy families, boys, and, more rarely, girls might go to school or have a tutor but much of their training was how to be a 'lady' or a 'gentleman'.
   This view of children is called preformationism: children were 'pre-formed' adults.

2. In the sixteenth century, the Puritans developed the idea that children were 'born sinners' and that their evil nature and wild spirit had to be broken, and that the parent's job of instilling the ability to tell right from wrong in their children was their most important job.

3. A century later, with the period of Enlightenment, and of human dignity and respect, children began to be seen in a new light, not as evil, but as raw material to be shaped by the parents. John Locke, a leader in this philosophy, saw children as a 'tabula rasa' or blank slate upon which the environment would write out what the future adult  would be. This line of thinking held that children should be treated with love and affection and taught reason in order to develop into rational and responsible adults.

4  .In the 18th century, the idea of children being born as 'noble savages' whose development to adulthood would unfold naturally in positive directions as long as the environment (especially parents) didn't ruin them. Jean Jacques Rousseau was the philosopher who is most closely associated with this philosophy. 

5.  The next stage in understanding 'childhood' came with the dawn of biological science, especially Darwin's theory of evolution. Through careful observation,  Darwin saw many similarities between the early stages of growth and development in other species and while some aspects of his speculations were proven wrong, his studies lead to careful systematic study of child development.

6. Early in the 1900's, the study of child development took off as a scientific endeavor. While parents often undertook 'baby biographies', descriptions of their own children's developmental milestones, these were often biased and unfocussed in terms of specific theories. (However, Jean Piaget, a 'giant' in the early years of the science of child development, was trained as a biologist and began his work on a theory of children's cognitive development with extraordinarily detailed and detached descriptions of his own children's infancies.)

7. At the turn of the century, another approach, normative studies, were begun by G. Stanley Hall and his student, Arnold Gesell. They attempted to gather objective data about average ('normal') children's behaviors at different ages. Gesell' information served as a guide to parents for the milestones to expect at each age.