Daryl B. Greenfield, Principal Investigator
Cognitive Inhibition Project:
The focus of information processing models has been on the activation of mental operations. Over the past several years, some of the basic tenets of information-processing approaches have come under question. Several theorists have proposed that developmental differences in inhibition may contribute significantly to age differences in children's thinking. The ability to inhibit task-irrelevant information is important not only for school-related learning but is necessary in dealing with everyday experiences.
Most of the evidence in support of developmental differences in inhibition comes from tasks involving unintentional inhibition. Unintentional inhibition occurs prior to conscious awareness when irrelevant information is automatically activated in conjunction with relevant information. For intentional inhibition to occur, the person must consciously decide that the information is irrelevant and then inhibit its activation. The major method used to study intentional inhibition has been the directed forgetting task, which has proven both theoretically and methodologically problematic.
Our work on inhibition focused initially on the development of an alternative methodology (which we named the associative interference task) for studying intentional inhibition. This task draws upon the well-documented and early developing competition that arises naturally in young children as they use multiple ways to categorize common objects. From an early age, young children categorize common objects (e.g., dog) both on the basis of associative relations (e.g., dog and bone) and on the basis of conceptual relations (e.g., dog and cow).
Currently we are using the associative interference task to study developmental trajectories of intentional inhibition processes in young children exposed to poverty. We already know that activation processes traditionally associated with information processing models are adversely affected by poverty. Theory would suggest, however, that inhibitory processes have both different and slower developing trajectories than activation processes. We are interested in understanding how intentional inhibition processes differ from activation processes in their development and how poverty influences inhibition development trajectories.