RT Journal Article
SR Electronic
T1 A resource-rational theory of set size effects in visual working memory
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 151365
DO 10.1101/151365
A1 Ronald van den Berg
A1 Wei Ji Ma
YR 2018
UL http://biorxiv.org/content/early/2018/06/13/151365.abstract
AB Encoding precision in visual working memory decreases with the number of encoded items. Here, we propose a normative theory for such set size effects: the brain minimizes a weighted sum of an error-based behavioral cost and a neural encoding cost. We construct a model from this theory and find that it predicts set size effects. Notably, these effects are mediated by probing probability, which aligns with previous empirical findings. The model accounts well for effects of both set size and probing probability on encoding precision in nine delayed-estimation experiments. Moreover, we find support for the prediction that the total amount of invested resource can vary non-monotonically with set size. Finally, we show that it is sometimes optimal to encode only a subset or even none of the relevant items in a task. Our findings raise the possibility that cognitive “limitations” arise from rational cost minimization rather than from constraints.