Undergraduate subjects processed the alphabet in one of three conditions: Visual Imagery (VI), in which subjects were instructed to visualize letters appearing one at a time, as on a movie screen; Speech Imagery (SI) in which subjects were instructed to say letters implicitly or silently; and a control condition Speech Explicit (SE) in which letters were said aloud. Conditions SE and SI produced virtually identical processing times (about 6·5 letters/sec.) while VI was much slower (about 2·5 letters/sec.). No consistent practice effects were observed over trials. In addition, each subject subjectively localized (in his head) the origin of the letter processing. Some notable differences were obtained, with the VI group indicating a more frontal localization than the others. It is suggested that imagery may follow different laws in different modalities.