Picture span test: Measuring visual working memory capacity involved in remembering and comprehension

The working memory system is assumed to operate with domain-specific (verbal and visuospatial) resources that support cognitive activities. However, in research on visuospatial working memory, an appropriate visual working memory task has not been established. For the present study, a novel task was developed: the picture span test (PST). This test requires memorizing parts of scene images while comprehending various scene situations simultaneously. Results of correlation analyses and a factor analysis among college students (n=52) validated that PST can predict visuospatial cognitive skills whereas a simple visual storage task and a verbal working memory task cannot. Furthermore, an error analysis indicated that inhibition is important for visuospatial working memory. Additionally, PST is considered to reflect individual differences in the visual working memory capacity. These findings suggest that the PST is appropriate for measuring visual working memory capacity and can elucidate its relationship to higher cognition.