The retention of automatically and effortfully encoded stimulus attributes

Abstract

Current research suggests that a memory trace is a record of the mental activity associated with an event, not a literal record of the event. Thus, more elaborate and effortful encoding is associated with better memory traces. Paradoxically, Hasher and Zacks′ (1979) theory holds that some information is encoded into long-term memory automatically—that is, effortlessly. However, tests of this theory have not assessed the durability of automatically encoded information for periods beyond a few minutes. We assessed memory of an effortfully encoded stimulus attribute, color, and of an automatically encoded attribute, spatial location. Intentional and incidental instructions did not differentially affect the encoding of these attributes, and both were remembered over a 24-h retention interval. It was concluded that automatically encoded information is encoded into long-term memory. The results suggest that color is also an attribute that may be encoded automatically.