Precision of working memory (WM) refers to the objective performance of individuals when trying to recall the features of the encoded WM items. Studies of precision in VWM aim to identify whether differences in WM performance within individuals are sensitive to individual states or traits. In this systematic review, we study VWM precision and whether it reflects true differences in ability to accurately store information, and thereby possibly a more sensitive measure than discrete VWM span alone. Sifting through 327 abstracts, we identified 34 relevant articles. After assessing these articles with regard to our inclusion criteria to test participants at two separate time points and have a sample size of at least fifteen participants, we found four longitudinal studies regarding VWM precision. One review author and two reviewers independently assessed all studies in the screening and selection process and extracted outcome measures, study characteristics, and, when possible, test-retest reliability metrics. Given the small and heterogeneous sample, this systematic review could not yet provide conclusive evidence on the sensitivity of VWM precision paradigms. Future research of VWM should include longitudinal studies of precision, and address both test-retest reliability in healthy adults and changes in precision during key developmental trajectory periods and in clinical populations.
Keywords: change detection; longitudinal; precision; reproduction; resolution; visual; working memory.