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The Nature
of Psychological Explanations
One major goal of psychological science is the construction, evaluation, and revision of explanations of behavior and/or mental processes. Psychological explanations are generalizations that describe the mechanisms by which those phenomena are produced by causal variables in people's external and/or internal environment. A mechanism is the pattern of changes precipitated by the operation and interaction of causal variables that produce explanandum phenomena within a specific range of circumstances. Mechanisms explain how causal influence is precipitated by the operation and interaction of causal variables and how this causal influence progresses over time to produce and maintain the phenomena to be explained within the context (set of circumstances) within which a given mechanism operates. Explanatory mechanisms provide a deeper level of understanding of explanandum phenomena because they place constraints on relevant causal dependencies, the range of circumstances within which those dependencies hold, and the circumstances within which they may change or fail to hold altogether. Because of the depth of understanding they provide, psychologists can use potential explanatory mechanisms to pose a wider range of empirically testable questions about behaviors and mental processes that they could with descriptive accounts alone. Explanatory modeling activities require students to identify constraints on the occurrence and manifestations of phenomena, use those constraints to derive hypotheses about those phenomena, and evaluate these hypotheses by comparing them to relevant empirical evidence. These kinds of activities can help students overcome many of their misconceptions about psychological phenomena by restructuring and systematizing their relevant background knowledge in ways that promote conceptual change.
The Role
of Activities in Concept Formation and Change
Current research in education suggests that new knowledge is often constructed
through a continuous interaction of thought and action.
Students' existing conceptual structure guides their choice of goal
directed actions and these actions guide their selection of relevant knowledge
for the current task.
The goal of explanatory modeling is to construct a model of the functional architecture of the system of causal variables that operate and interact to produce and maintain the phenomenon to be explained. The recommended strategies for achieving
this goal include the following activities. Initial candidate models are retrieved or
constructed by using relevant domain knowledge to identify (1) a class of real world systems that are capable of producing the phenomenon to be explained and (2) the class of mechanisms (mechanism schema) by which those systems generates these phenomena. Then, the hypothesized mechanism schema is used to construct an algorithm for mapping known inputs (antecedent conditions) to outputs (the explanandum phenomenon and byproducts of the system's operation). Inferences
are made by mentally simulating the operation of the candidate model in accordance with the algorithm to
generate new states. As the simulation proceeds, the new states that are generated are
compared to relevant empirical evidence and feedback from these comparisons is used to revise or
elaborate existing models or reject them and start again. The modeling procedure
involves a process of generating new and modifying existing models until a
model is achieved that the student considers to be satisfactory. During these modeling activities, students' existing concepts will guide their
(1) use of relevant knowledge to retrieve or construct initial models, (2) search for and
interpret relevant empirical evidence, and (3) use of relevant evidence to modify their existing
models at each stage of the modeling process.
The degree to which students' proposed model
components capture relevant constraints on the phenomenon under study will determine how well their
models can account for its occurrence. When students' models fail
to provide a good account of particular occurrences of the target phenomenon,
subsequent reflection and discussion can lead students to revise their
models, and this can lead to further model evaluation. This process
of model evaluation and revision often leads students to modify their relevant
concepts. The benefits of student engagement in explanatory modeling activities can be enhanced by activities that involve metacognitive reflection on and discussion of their modeling activities. For example, students might reflect on how the structure of their explanatory
concepts motivates the construction, evaluation, and revision of their
models. Students might also reflect on their use of psychological concepts to separate things into distinct
kinds, and how they relate these kinds to each other.
The Role
of Explanatory Modeling in Teaching Psychology
When properly integrated with other kinds of instructional methods, explanatory
modeling activities can help students to better understand and evaluate important theoretical and methodological issues in psychology. These issues are often difficult for students to understand because they involve the applications of scientific methods of investigation to behaviors that are extremely complex and endlessly variable. Evaluation presupposes
understanding because students cannot properly evaluate what they do not
properly understand. Evaluation is particularly important in the social and
behavioral sciences where alternative theories often compete for acceptance.
The complexity and variability of psychological phenomena reflects the common causal structure of the kinds of situations in which those phenomena typically occur. In real world situations, the behavior of humans and other animal species are embedded in an ongoing process of continuous, dynamic activity that is maintained by constantly changing stimuli in their internal and external environment.
GLN Consulting can recommend ways of helping students to better understand these behaviors and the situations in which they occur by bringing together information resources, explanatory modeling
activities, and instructional strategies.
¹ Consider, for example, an early and now classic task experiment by Wason (see Johnson-Laird, 1983 for a discussion of this and subsequent research)
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