We present evidence that the comprehension of illustrated text makes use of the visuospatial sketchpad component of working memory. The results from three experiments demonstrate that the comprehending of texts that are accompanied by pictures interferes with the performance of a spatial short-term memory task more than does the comprehending of texts that have no pictures. A fourth experiment demonstrates that the interference is found only when there is a requirement to comprehend the text; that is, the simple presentation of the texts and their pictures did not degrade performance on the spatial task. Finally, we show that the comprehension of illustrated texts does not differentially interfere with a verbal short-term memory task. These results are consistent with the claim that illustrations accompanying a text encourage the formation of a spatial mental model with the use of the working memory's sketchpad.Pictures increase comprehension of texts in virtually all situations (Levie & Lentz, 1982). Our goal was to investigate one component of the process by which this might occur, the use of the visuospatial component of working memory (Baddeley, 1992) to construct spatial mental models. We tested this idea in a series of experiments in which we used concurrent task methodologies. Our basic finding was that the comprehending of texts with pictures disrupted the performance of a spatial concurrent task, but had no effect on the performance of a verbal concurrent task. Not only was this disruption selective in regard to the concurrent task that was disrupted, it also occurred only within the context of a comprehension task.In most theories of text comprehension, it is agreed that comprehension requires the construction of a referential representation of the meaning of the text: a representation that includes the objects and events being described. Such a representation adds to the literal meaning of the text by incorporating relevant world knowledge. In different theories, referential representations have been given various names, such as situational representations (Perrig & Kintsch, 1985) and mental models (Johnson-Laird, 1983 is about rather than the text itself (Glenberg, Meyer, & Lindem, 1987), so that the structure of the objects being described takes precedence over the structure of the text. Our conception of mental models (Glenberg, Kruley, & Langston, in press) differs from other referential representations in that we take seriously the claim that mental models are analogical. Thus, we are particularly interested in texts that describe spatial layouts or that describe dimensions that are isomorphic to spatial layouts. In these domains, a mental model is hypothesized to consist of representational elements arrayed in the spatial medium of the visuospatial component of working memory.Support for this formulation is provided by some recent research. Glenberg and Langston (1992) considered several ways in which pictures could aid comprehension, including that pictures simply repeat information, that pictu...

Repetition priming and recognition memory for numbers were measured in four experiments using single-digit addition. Results of the first two experiments indicate that when numbers were presented as number words and dot configurations, preexposure of the same problem in the same notation produced greater reaction-time benefit than did preexposure of the same problem in Arabic-digit notation. In contrast, when numbers were presented as Arabic digits, preexposure of the same problem in Arabic digit, number word, and dot notation produced the same amount of priming. In the third experiment, priming was shown to be greatest, for all three notations, when the task performed on preexposure trials (addition or multiplication) matched the task performed on repetition trials (addition). Results of the fourth experiment, measuring recognition memory, were comparable to the priming results in the sense that memory was superior when notation matched across repetitions if the test involved number words and dot configurations but not Arabic digits. These data are interpreted in terms of models of numerical cognition, and they support the hypothesis that the influence of surface form on repetition priming depends on the typicality of the input for the task.Numbers can be represented in many different ways. They can be represented by Arabic digits and Roman numerals, as well as by other numeration systems that did not reach Western culture. In some cases, notations were specifically developed for calculation. The Arabic notation, for example, with its place-value system is particularly well suited for both written and mental calculation (Zhang & Norman, 1995). Even in single-digit computations, different notations may have different consequences for mental operations. Analogical systems may encourage counting procedures, whereas other notations may result in retrieval of memorized number facts (e.g., 5 + 5 = 10). The organization of the system of number facts may itself depend on the structure ofa particular numeration system. The aim of the present experiments was to examine the influence of notation on the representation of numerical information.The effect ofperforming an arithmetical operation presented in one notation on the subsequent performance of

One experiment investigated the effects of distortion and multiple prime repetition (super-repetition) on repetition priming using divided-visual-field word identification at test and mixed-case words (e.g., goAT). The experiment measured form-specificity (the effect of matching lettercase at study and test) for two non-conceptual study tasks. For an ideal typeface, super-repetition increased form-independent priming leaving form-specificity constant. The opposite pattern was found for a distorted typeface; super-repetition increased form-specificity, leaving form-independent priming constant. These priming effects did not depend on the study task or test hemifield for either typeface. An additional finding was that only the ideal typeface showed the usual advantage of right hemifield presentation. These results demonstrate that super-repetition produced abstraction for the ideal typeface and perceptual individuation for the distorted typeface; abstraction and perceptual individuation dissociated. We suggest that there is a fundamental duality between perceptual individuation and abstraction consistent with Tulving's (1984) distinction between episodic and semantic memory. This could reflect a duality of system or process.