SUMMATION OF ACTIVATION - EVIDENCE FROM MULTIPLE PRIMES THAT CONVERGEAND DIVERGE WITHIN SEMANTIC MEMORY

Six experiments addressed the combinatorial influence of multiple rela ted primes in naming, lexical decision, and relatedness judgment perfo rmance. Primes either converged on a single semantic representation (e .g., LION-STRIPES-TIGER) or diverged onto distinct semantic representa tions (e.g., KIDNEY-PIANO-ORGAN). The facilitatory influence of 2 rela ted primes was well predicted by the sum of the influences from the si ngle-related-prime conditions (a) for both convergent and divergent pr imes, (b) in lexical-decision and naming, (c) across varying prime-tar get stimulus onset asynchronies, and (d) under target-degradation cond itions that increased the priming effects. The relatedness-judgment ta sk yielded an additive pattern of priming for convergent prime conditi ons; however, an underadditive pattern of priming was found for diverg ent prime conditions. Discussion focuses on the role of attentional sy stems that modulate the type of information used to perform a given ta sk.