Figure 1.

Paradigm. Our experimental paradigm was designed to tease apart activation related to word retrieval, word recognition, and articulation. In all trials, 3 stimuli were simultaneously presented as a “triad,” with 1 stimulus above and 2 stimuli below. Word retrieval was assessed during picture naming (condition 1) and reading aloud (condition 2). Articulation without word retrieval involved articulating “1,2,3” in response to pictures of unfamiliar nonobjects (condition 3) or unfamiliar (and meaningless) strings of Greek letters (condition 4). Word recognition and semantic processing were assessed during semantic decisions (e.g., matching Piano to Harp rather than Oven) on pictures (condition 5) or words (condition 6), using a finger press response. Perceptual processing was assessed during a physical identity match on the meaningless Greek letter strings (condition 7) or pictures of nonobjects (condition 8), using a finger press response.