Activation levels of plausible alternatives in conversational negation.

Negation is often used to contradict or correct (e.g. There is no dog here.). While rejecting some state of affairs that is presumed to hold for the recipient (e.g. There is a dog here.), the speaker might implicitly suggest a set of plausible alternatives (e.g. There is a wolf instead.). Prior work indicates that alternatives are highly relevant to the comprehension of sentences involving focus: in priming studies, listeners infer plausible alternatives to focused items even when they are not contextually available. So far it is unclear whether negation similarly activates an automatic search for plausible alternatives. The current study was designed to investigate this question, by looking at the activation levels of nouns after negative and affirmative sentences. In a series of priming experiments, subjects were presented with negative and affirmative sentences (e.g. There is an/no apple.), followed by a lexical decision task with targets including plausible alternatives (e.g. pear), as well as semantically related but implausible alternatives (e.g. seed). An interaction of Sentence Polarity and Prime-Target Relation was expected, with negation facilitating responses to plausible alternatives. Results of the first experiment were numerically in line with the hypothesis but the interaction just missed significance level. A post hoc analysis revealed the expected significant interaction. Possible roles of sentential context and goodness of alternatives are discussed. A further experiment confirms that the goodness of alternatives is in fact critical in modulating the effect.