Instability in memory phenomena: A common puzzle and a unifying explanation

Abstract

In mixed lists, stable free recall advantages are observed for encoding conditions that are unusual, bizarre, or attract extensive individual item elaboration relative to more common encoding conditions; but this recall advantage is often eliminated or reversed in pure lists. We attempt to explain this ubiquitous memory puzzle with an item-order account that assumes that (1) free recall of unrelated lists depends on order and item information; (2) unusual items attract greater individual item-processing but disrupt order encoding regardless of list composition; and (3) list composition determines differences in order encoding across unusual and common items. We show that the item-order account provides a unifying explanation of five memory phenomena for which the requisite data exist. The account also successfully anticipates pure-list reversals, in which the standard mixed-list recall pattern is obtained in pure, structured lists, a finding that competing accounts cannot handle. Extending the item-order account to other "established" recall phenomena may prove fruitful.