Abstract
How detailed are long-term memory (LTM) representations as compared to those of working memory (WM)? Recently, Brady et al. (2013) suggested that both types of memory are constrained by the same bound on fidelity, after which the memory representation is lost. In their experiments, however, WM performance may have been contaminated with LTM representations. Here, we aimed to replicate their findings, while tapping a purer measure of WM. In addition, we examined whether a representation of an item can exist alongside the absence of color information. Participants were presented with colored real-life objects and were asked to remember both the items and their color. At test, participants judged whether the objects, presented in grey, had previously appeared (item memory) and then chose their color from a continuous-color wheel (color memory). This procedure allowed us to examine the memory of an item separately from the memory of its corresponding color, in a within-subject design. In the WM condition, participants had three seconds to encode three colored objects, after which they performed the item- and color-memory tasks for only a single object out of the three. In the LTM condition, participants were presented with hundreds of items, one at a time for three seconds each. They were subsequently tested for item and color memory. We calculated the variability of internal representations of color (fidelity) and the probability of forgetting an object's color. In replication of Brady et al. (2013), the probability of guessing in LTM was found to be higher than in WM. However, the critical analysis of fidelity revealed significantly better fidelity for WM. We also found that items can be remembered while their color is lost, rendering item and color information to be partly independent. We discuss the theoretical implications of different boundaries of WM and LTM.
Meeting abstract presented at VSS 2017