Words are primed by semantically related words: subjects are faster to make a lexical decision about “BUTTER” if it's preceded by “bread” than if it's preceded by “nurse.”
“When a word is preceded by a semantically related word, it becomes easier to classify as a word. Latencies to recognize CAT, for example, are shorter if it is preceded by DOG than if its is preceded by SIX.”
Possibility of embedding the visual lexical decision task (LDT) in a more elaborate experimental design - in effect using the LDT as a tool to look at associated phenomena. Suppose we have two groups of words consisting of matched pairs such as “nurse” and “flood”. Because the groups are matched along the dimensions of frequency, length, and syntactic category, we have no reason to expect any consistent, overall reaction time difference between the two groups of words when they are presented in a lexical decision experiment. Suppose now, however, that we allow each of the real words in the “nurse”-group to be preceded by a word that is semantically related to it: “nurse” would be preceded by “doctor”, for instance. The related word might be immediately before its partner, or one or two words before in the sequence presented to subjects. We would typically find that the second word in these related couples would be primed: subjects would respond to “nurse”, following soon after “doctor”, faster than to a matched target word like “flood”, not preceded by a semantically related word. (If we had a slightly different experimental design, we could contrast “nurse” preceded by “doctor” in one condition, with “nurse” preceded by an unrelated word, “carpet”, in a second condition. The former would be primed and recognised faster.)