The role of decision biases in semantic priming effects

At least a part of semantic priming effects observed in binary decision tasks is supposed to be caused by decision biases. A semantic relationship between prime and target could positively bias a "yes" response, whereas the absence of a relationship would instead favour a "no" response to the same target. We tested this assumption with a semantic categorization task in which participants were induced,to associate different values - positive, negative, or neutral - to each of the categorization decisions. Although semantic priming effects were obtained even with negatively valued decisions, they were Substantially enhanced with positively valued decisions, confirming the influence of a decision bias induced presumptively by a post-lexical relatedness judgement.