Preattentive and Attentive Visual Information Processing

Twelve 12 experiments are described in this report. The first nine 9 are concerned with the hypothesis that the identification of the values of stimulus features in multielement visual displays requires serial processing. Contrary to this hypothesis, the weight of the evidence suggests that feature identification can be carried out by spatially parallel processes. The remaining three 3 experiments are concerned with the ability to extract semantic information from several stimuli in parallel. Both alphanumeric character classification and lexical i.e., word vs. nonword decisions can be accomplished by parallel processes, but semantic categorization of words cannot. The implications of these findings for theories of attention are discussed. Keywords Attention, Lexical access, Perception, Semantic processing, Subsidizing, Texture perception, Vision, Visual search.