Neighborhood Size and Neighborhood Frequency Effects in Word Recognition

What are the effects of a word's orthographic neighborhood on the word recognition process? Andrews (1989) reported that large neighborhoods facilitate lexical access (the neighborhood size effect). Grainger, O'Regan, Jacobs, & Segui (1989) reported that higher frequency neighbors inhibit lexical access (the "neighborhood frequency effect"). Because neighborhood size and neighborhood frequency typically covary (words with large neighborhoods will usually possess higher frequency neighbors), these findings would seem to contradict one another. In the present study, 6 experiments on the effects of neighborhood size and neighborhood frequency indicated that, at least for low-frequency words, large neighborhoods do facilitate processing. However, the existence of higher frequency neighbors seems to facilitate rather than inhibit processing. The implications of these findings for serial and parallel models of lexical access are discussed. Much of the research on visual word recognition has focused on the issue of lexical access. Consequently, a number of models of the lexical access process have been proposed, each providing a slightly different account of the various factors that affect this process. Consider, for example, the factor that is probably the most studied in this literature—printed-word frequency. The standard finding is that high-frequency words are processed faster than lowfrequency words. In Forster's (1976) serial search model, this effect is explained in terms of a serial-search process. According to the model, the entries in the lexicon are organized according to word frequency. The search for a match between the sensory input and the correct lexical entry proceeds in a serial manner, starting with the closest matching higher frequency entries. Thus, high-frequency words are identified more quickly than low-frequency words by virtue of their order in the search set. Alternatively, in "activation-b ased" models, such as McClelland and Rumelhart's (1981) interactive-activation model, frequency effects are attributed to the higher resting activation