RT Journal Article
A1 Shin, Hongsup
A1 Zou, Qijia
A1 Ma, Wei Ji
T1 The effects of delay duration on visual working memory for orientationShin, Zou, & Ma
JF Journal of Vision
JO JOV
YR 2017
DO 10.1167/17.14.10
JF Journal of Vision
VO 17
IS 14
SP 10
OP 10
SN 1534-7362
AB  We used a delayed-estimation paradigm to characterize the joint effects of set size (one, two, four, or six) and delay duration (1, 2, 3, or 6 s) on visual working memory for orientation. We conducted two experiments: one with delay durations blocked, another with delay durations interleaved. As dependent variables, we examined four model-free metrics of dispersion as well as precision estimates in four simple models. We tested for effects of delay time using analyses of variance, linear regressions, and nested model comparisons. We found significant effects of set size and delay duration on both model-free and model-based measures of dispersion. However, the effect of delay duration was much weaker than that of set size, dependent on the analysis method, and apparent in only a minority of subjects. The highest forgetting slope found in either experiment at any set size was a modest 1.14°/s. As secondary results, we found a low rate of nontarget reports, and significant estimation biases towards oblique orientations (but no dependence of their magnitude on either set size or delay duration). Relative stability of working memory even at higher set sizes is consistent with earlier results for motion direction and spatial frequency. We compare with a recent study that performed a very similar experiment. 
RD 8/19/2019
UL https://doi.org/10.1167/17.14.10