Colin M. MacLeod
University of Toronto at Scarborough
The concept of cognitive inhibition--that processes exist to suppress a response or thought for a period of time--has sharply increased in prevalence over recent years. This is particularly true in the domains of attention and memory. Inhibition, in one form or another, has been invoked as at least partially underlying a host of phenomena, among them negative priming, directed forgetting, and the Stroop effect, to cite just three familiar examples. Indeed, the concept has even been incorporated into the name of some cognitive phenomena, such as retrieval inhibition and inhibition of return. Yet in these cognitive situations and in many others, the evidence for inhibition is far from unequivocal, and domain-specific alternative accounts continue to emerge. In this talk, I will use a case study approach, examining a few attention and memory tasks, to argue that the concept of inhibition may not be necessary and may not be helping us to understand interference effects in cognition. I will then describe a small set of well established cognitive mechanisms that can explain what appear to be inhibitory effects without requiring any inhibitory process.