Friends in low-entropy places: Letter position influences orthographic neighbor effects in visual word identification

In visual word recognition, having more orthographic neighbors (words that differ by a single letter) generally speeds access to a target word. But neighbors can mismatch at any letter position. In light of evidence that information content varies between letter positions, we consider how neighbor effects might vary across letter positions. Results from a word naming task indicate that response latencies are better predicted by the relative number of positional friends and enemies (respectively, neighbors that match the target at a given letter position and those that mismatch) at some letter positions than at others. In particular, benefits from friends are most pronounced at positions associated with low a priori uncertainty (positional entropy). We consider how these results relate to previous accounts of position-specific effects and how such effects might emerge in serial and parallel processing systems.