Parallel and Serial Processing

Abstract

AbstractThis chapter reviews theoretical and empirical progress that has been made in answering the question “Is processing parallel or serial?” Answers to the question are complicated because the distinction between parallel and serial processing interacts with other basic distinctions, including exhaustive versus self‐terminating search, limited versus unlimited capacity, discrete versus continuous processing, and stochastic versus functional independence. Because of these complications, parallel and serial models readily mimic each other's predictions. Empirical answers to the question are complicated as well because different procedures invoke parallel and serial processing in different ways, and because detailed theories of empirical phenomena often mimic each other's predictions. The chapter reviews progress in distinguishing parallel and serial models of memory search, visual search, dual‐task performance, redundant stimulation, and memory retrieval. It addresses recent alternatives to parallel processing, such as coactivation and mixture models. It ends by evaluating the amount of cumulative progress that has been made in answering the question “Is processing parallel or serial?” and by speculating about prospects for progress in the future.