When bivalent stimuli (i.e., stimuli with features for two different tasks) appear occasionally, performance is slower on subsequent univalent stimuli. This "bivalency effect" reflects an adjustment of cognitive control arising from the more demanding context created by bivalent stimuli. So far, it has been investigated only on task…

Three classes of research on reading are identified. The articles of this section pertain to investigation of the organization and operation of basic processing mechanisms underlying skilled reading; each is described briefly and commented upon. Particular attention is devoted to the articles on context effects. (Author/RD)