Classification Accuracy Across Multiple Tests Following Item-Method Directed Forgetting

Recall of line-drawing pictures paired at study with an instruction to either remember (TBR items) or to forget (TBF items) was investigated. Across three 7-minute tests, net recall (items reported independent of accuracy in instructional designation) and correctly classified recall (recall conditional on correct instructional designation) showed directed forgetting. That is, for both measures, recall of TBR items always exceeded recall of TBF items. Net recall for both item types increased across tests at comparable levels showing hypermnesia. However, across tests, correct classification of both item types decreased at comparable levels. Collectively, hypermnesia as measured by net recall is possible for items from multiple sets, but at the cost of accurate source information.