Search times for combinations of visual,phonemic, and semantic targets in reading prose

Subjects read passages of prose, canceling targets that were visual (letters), acoustic (phonemes), or semantic (words of a specified category). Each of the targets occurred singly and in all possible double and triple combinations. Comparison of the search times reveals that semantic processing adds little or no extra time when combined with acoustic or with visual and acoustic searches, i.e., it occurs in parallel. Other combinations of processing yield search times that are slightly faster than a serial model would predict and are best interpreted as reflecting an overlapping sequence of operations.