Role of stimulus environment and duration of processing in long term memory

A MAJOR concern of current memory research is to identify how information is encoded and transferred from short term memory (STM) to long term memory (LTM)^1,2. It has been reasoned that while an item remains in STM, it can be maintained through rehearsal; as a consequence, the corresponding LTM trace is built up. Thus, one may postulate that the adequacy of an item's registration in LTM is a positive function of the length of its stay in STM. Such a mechanical and simplistic account of memory has been challenged by a series of experiments which showed that when short term storage times were measured, these times did not predict long term retention^3,4. We report here an experiment which manipulated the processing time as well as the processing context and showed that the processing time had differential effects, sometimes beneficial, sometimes harmful, and sometimes neutral, on an item's long term retention, depending in which type of processing context the item was embedded. Such results argue for a perceiver-environment interactive theory of memory.