Evidence for False Memory before Deletion in Visual Short-Term Memory

Forgetfulness results in interference and/or deletion. Visual shortterm memory (VSTM) gradually decays as the retention time elapses, causing forgetfulness. Little is known about forgetfulness in VSTM, while substantial studies on VSTM have focused on the process of memory encoding, often with control of attention. Evidences suggest that the prefrontal cortex may contribute to maintain short-term memory during extended retention periods while the posterior parietal cortex may support the capacity-limited store of visual items. Here we conduct a visual memory experiment to measure the levels and source of memory decay. In particular, multiple retention intervals were used between the presentation of a study array and a cue. The results show that the correct response to cued objects decreased as retention interval increased while that to uncued and novel objects remain unchanged. These data indicate that forgetfulness in VSTM is primarily due to interference rather than memory deletion.