Distinctiveness effect due to contextual information in a categorization task

The main objective of our study was to confirm that the distinctiveness effect could emerge in implicit memory tasks and to show that the specificity of an item can be varied by manipulating the contextual information associated with the item during encoding. In an encoding phase and test phase, participants had to categorize target words as referring to artifactual or natural items. Each target word was associated with a context consisting of a colored frame in which the word was presented. To manipulate the distinctiveness of the contextual information, 75 % of the words were encoded with the same color (frequent context) and the remaining 25 % with a different color (rare context). We tested the context effect by presenting words in the test phase with a context of either the same color as in the encoding phase or the other color. The results confirmed our predictions and are discussed in the theoretical framework of episodic memory models.