Neighborhood effects using a partial priming methodology: Guessing or activation?

K. Pugh, K. Rexer, M. Peter, and L. Katz (1994) found longer lexical-decision latencies to letter words when an ambiguous letter (one from which neighbors could be formed) was delayed than when an unambiguous letter (one from which no neighbors could be formed) was delayed. They suggested that this was due to competition between partially activated words. However, K. I. Forster and D. Shen (1996) suggested that this effect may be due to participants' generating hypotheses on the basis of the previewed trigram. The authors conducted 2 experiments that used a partial priming methodology and found that lexical-decision latencies were longer to words preceded by ambiguous trigrams than unambiguous trigrams when (a) the target was the highest frequency member in its neighborhood and (b) the prime was masked and presented for 60 ms. These results are inconsistent with Forster and Shen's prediction of no effect of prime ambiguity under these conditions, and they indicate that the ambiguity effect was not due to hypothesis generation on the basis of the partial primes.