Is there implicit memory without attention? A reexamination of task demands in Eich's (1984) procedure.

The relation between memory and attention has been of long-standing interest. Eich (1984) made an important discovery of implicit but not explicit memory for contextually determined homophones (e.g., taxi-FARE) presented in a channel to be ignored within a selective listening procedure. However, his slow rate of presentation of shadowing task materials may have allowed frequent attention shifts to the allegedly ignored channel. With a direct replication of Eich's timing parameters, we reproduced his results, but when the attended channel was presented twice as fast as Eich's, implicit memory for the to-be-ignored words vanished. Our results contradict claims of extensive semantic processing of unattended auditory information in this task.