Abstract
Forgetting impacts on almost all aspects of cognitive function in everyday life. But in spite of its significance, the underlying mechanisms remain unclear. It has been suggested that a rapid decrease in memory performance is a result of gradual fading or sudden termination of memory representations as time passes. But others contend that interference from newly encoded items, rather than the passage of time, is the key mechanism underlying forgetting. We studied the precision of memory recall, varying the number of items and duration of delay. Critically, in addition to analysing subjects’ reports with respect to the true values of the probed object, we also studied whether their recall might be biased by other items in the memory array that were not probed. Our results support a novel perspective about the factors responsible for short term forgetting. Both time and interference are essential for forgetting and interact in a highly specific manner. While single items can be maintained in memory with high fidelity, additional items degrade each other's representation as time passes by competing in working memory. Specifically, interference between items is associated with decreasing precision caused by increased probability of binding failures - as evidenced by increasing report of features of non-probed items. Thus, while memory of single features is fairly robust across time, the links connecting different features belonging to an object are the ones most vulnerable to degradation and forgetting.
Meeting abstract presented at VSS 2012