Identification of words and letters within words.

Three experiments were designed to examine the way letters are identified when they are presented within the context of a word. The first two experiments demonstrated that identification speed is facilitated if the within-word letter position of the target location. If the locational information is specified before the word is displayed (e.g., it is always the first letter), but if the locational information is presented along with the display (e.g., the target position is underlined) reaction time is considerably slower. A model of the identification process was described which assumed that subjects first identify the word, then analyze the contents of all the letter positions in order to encode each letter. Finally, the identification can occur when subjects shift their attention to the target location. If the locational information is given before the display, the attention shift can occur as the letter positions are being analyzed and encoded, but the shift must be delayed until after the analysis if the locational information is part of the display. An implication of the model is that prior to identifying the contents of the target position, the subject should always have an encoding of all the letters in the word, and the results of the third experiment supported that expectation.