Saturday, January 12, 2008

Siegler's Strategy Choice Model

Developmental Psychology can be understood as the study of how changes occur in cognitive thinking in kids from birth through adolescence. In many models of cognitive development, children are depicted as thinking or acting a certain way for an extended period of time. Then, they undergo a brief and sometimes mysterious transition and begin to act and think in a new way. Siegler, however, prefers to focus on the changes more than on the stages, and sees change as variable and gradual for things like arithmetic or spelling. Further, there are some problems (such as number conservation) where there is really only one logical strategy. After some time experimenting with different strategies, both in progressive and regressive directions, most children will focus on the best, most logical strategy, and lock onto it for much of the remainder of their lives.

When considering learning disabilities, especially in reading or in math, the applicability of Siegler’s strategy choice model becomes apparent. Young children’s brains are highly active, with synaptogenesis peaking by age six or so. Following the periods of synaptogenesis there is widespread synaptic pruning, to make the synaptic pathways more efficient and speedy. So it is during this time of great neural change when students (at least, in the United States) are first learning basic mathematics and reading skills. Given the proliferation of neural pathways, it makes sense that the normally developing child will use a variety of different strategies when faced with the same or similar problems. For example, there are at least three common strategies that children can use for addition. The first is fact retrieval: 3 + 3 always equals 6. The second is the min strategy, where kids count up from the larger number: 9 +2 = (9 + 1) + 1 = 10 + 1 = 11. The third is decomposition into easily manipulated numbers: 19 + 22 = 19 + 20 + 2 = 39 + 2 = 41. Normally developing children will ultimately lock into one of these or another strategy when faced with a random addition problem. Likewise, there are different strategies for reading words – letter by letter, phoneme by phoneme, whole-word memory-based retrieval, and so forth. As the processes of synaptic pruning begin to occur, the best strategies are locked in to continue to be used.

A question arises, however: what happens with kids with learning disabilities, or non-normal development? Siegler’s model provides for two possible explanations. First, perhaps while the brain is undergoing its normal course of synaptogenesis and synaptic pruning, the child has not had enough experience with the various strategies for reading or math (or anything else) – so by the time synaptic pruning occurs, it is unclear which neural pathways are stronger or more efficient. That leaves the child unable to become “expert” at that particular task, as there is no clear efficient pathway left. Second, perhaps the child has had sufficient opportunity to experiment with the various strategies, but the synaptic pruning processes occur in a somewhat haphazard, non-systematic way, which leaves the child forever locked into a pattern of experimentation and variability. That is, the child does not have the opportunity to lock in on a best-choice strategy because of neural/biological limitations.

While neither of these possibilities precludes the children from gaining efficiency over a long period of time, they leave them behind the rest of their peers, significantly slowed down by the wide variety of problem-solving strategies available to them.

Citation: Siegler (1994). Current Directions in Psychology Science.

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