Two experiments examined the graded similarity effect in the repetition pri
ming of familiar face recognition. From the model of repetition priming pro
posed by Burton, Bruce, and Johnston (1990) it was predicted that similarit
y effects may be a confound of stimulus preparation. Experiment 1 was used
to discount this hypothesis, but failed to replicate a pattern of graded pr
iming related to the similarity of prime and target faces. Experiment 2 att
empted a more extensive investigation using two different measures of prime
-target similarity. The results replicated Ellis, Young, Flude, and Hay's (
1987) finding that similar primes confer more priming than dissimilar ones,
but found no correlation between amount of priming and the degree of prime
-target resemblance for either similarity metric used. In view of these fin
dings the mechanism of repetition priming in familiar face recognition is d
iscussed.