Dissociated backward priming effects in lexical decision and pronunciationtasks

Backward priming was examined at 150- and 500-msec prime-target stimulus on set asynchronies (SOAs) using visually presented primes and targets in lexi cal decision and pronunciation tasks. Two kinds of backward relations were used: compound items for which targets and primes formed a word in the back ward direction (e.g., prime: HOP; target: bell), and noncompound items for which targets and primes did not form a word but were associatively related in the backward but not the forward direction (e.g., prime: BABP; target: stork). Results showed that backward priming effects were equivalent for co mpounds and noncompounds. However, for lexical decisions, backward priming occurred at both SOAs, whereas for pronunciation, it occurred only at the 1 50-msec SOA. We discuss how this SOA-dissociated backward priming effect in lexical decision and pronunciation tasks poses a serious challenge for all theories of semantic priming.