Abstract
Visual working memory (VWM) is typically found to be severely limited in capacity, but this limitation may be ameliorated by providing familiar objects that are associated with knowledge stored in long-term memory. However, comparing meaningful and meaningless stimuli usually entails a confound, because different types of objects also tend to vary in terms of their inherent perceptual complexity. Here, we present two sets of findings that aim to demonstrate that object meaning can benefit VWM independently from variations in perceptual complexity. For instance, in study 1, we demonstrate that simple (unicolored) objects were remembered better than more complex, yet meaningless color-shape configurations. However, perceptually identical, complex but meaningful items revealed a reliable VWM performance benefit relative to the meaningless configurations (with the capacity estimates for meaningful objects in fact being comparable to the simple, unicolored objects). This demonstrates that the effects of meaning upon object memory may be dissociated from concurrent variations of perceptual complexity. In addition, study 2 demonstrates that actively learning the meaning of previously meaningless objects can improve VWM capacity beyond basic stimulus repetition effects. For instance, learning the meaning of Chinese characters enhanced VWM performance, relative to a second set of characters that were just viewed passively (without providing their meaning). This shows that learning generates meaning, which in turn enhances VWM performance. Together, these findings show that the short-term retention of an object depends on object knowledge, where knowledge may be derived from associations about an object’s meaning in long-term memory thereby enhancing the representation of an object that is currently maintained.