Looking for graded recollection: manipulating the number of details to be recollected does not affect recollection variance.

Recollection has been the subject of much debate, with some models maintaining that it is subject to a threshold, some maintaining that it is a continuous process, and some maintaining that both are true. Threshold models maintain that recollection can fail (i.e., fall below threshold), whereas signal detection models treat recollection as a continuous process. Recent research has revealed that some manipulations can influence this behavior, but the general reasons why threshold patterns emerge in some conditions and graded patterns emerge in others are still unclear. One potential explanation is the number of retrieved details; recollection of stimuli with few details may succeed or fail, whereas recollection of stimuli with many details may be graded. If this is true, manipulating the amount of detail should produce threshold patterns for "few details" conditions, but more graded patterns for "many details" conditions. This hypothesis was tested in six experiments examining source memory, and the number-of-details manipulation consistently failed to affect the nature of recollection. Overall, the results suggest that the amount of information available to be retrieved does not, by itself, explain recollection variability.