In two experiments, we examined individual differences in metaphor processing. In Experiment 1, the subjects judged the literal truth of literal, metaphorical, and scrambled sentences. Overall, metaphors were more difficult to judge as false, in comparison with scrambled controls, suggesting that the metaphorical meaning was being processed automatically. However, there were individual differences in that high-IQ subjects showed more interference. These effects were reflected in ERP amplitude differences at the onset of N400 and after the response. In Experiment 2, the subjects completed IQ tests and a series of working memory tests and then rated and interpreted the same set of metaphors. The results showed that IQ was correlatedwith working memory capacity and that low-IQ subjects had similar ratings but poorer quality interpretations than did high-IQ subjects. The results were most consistent with a constraint satisfaction approach to metaphor comprehension.

The capacity to reorient in one's environment is a fundamental part of the spatial cognitive systems of both humans and nonhuman species. Abundant literature has shown that human adults and toddlers, rats, chicks, and fish accomplish reorientation through the construction and use of geometric representations of surrounding layouts, including the lengths of surfaces and their intersection. Does the development of this reorientation system rely on specific genes and their action in brain development? We tested reorientation in individuals who have Williams syndrome (WS), a genetic disorder that results in abnormalities of hippocampal and parietal areas of the brain known to be involved in reorientation. We found that in a rectangular chamber devoid of surface feature information, WS individuals do not use the geometry of the chamber to reorient, failing to find a hidden object. The failure among people with WS cannot be explained by more general deficits in visualspatial working memory, as the same individuals performed at ceiling in a similar task in which they were not disoriented. We also found that performance among people with WS improves in a rectangular chamber with one blue wall, suggesting that some individuals with WS can use the blue wall feature to locate the hidden object. These results show that the geometric system used for reorientation in humans can be selectively damaged by specific genetic and neural abnormalities in humans.geometric processing | neural specificity | Williams syndrome | navigation | spatial representations W hen rats, human toddlers, or adults are disoriented in a chamber, they search for targets using geometric properties of the layout, often ignoring quite salient nongeometric cues (1-5). This pattern has led scientists to hypothesize that reorientation in animals (including humans) is guided by a cognitive module that engages geometric properties of layouts such as the lengths of surfaces, the angles of their intersections, and geometric sense (i.e., "left-" and "right-ness"), but does not engage nongeometric information such as surface color (2-4). Others have argued against the idea of a geometric module, proposing instead a model in which reorientation is guided by a range of information available in the environment, including both geometric and nongeometric properties. In the latter model, cues are selected and used on the basis of their reliability over the organism's learning history (6, 7). Both views, however, acknowledge that geometric representations of layouts are privileged, playing a primary role in reorientation across a large range of species.This privileging of geometric representations in reorientation tasks resonates with the idea of domain specificity-one of the hallmarks of modular systems as proposed by Fodor (8). Other characteristic properties of modular systems include impenetrability, ontogenetic invariance, characteristic breakdown patterns and neural localization. Although much debate over the modularity of the geometric system that supports reorien...

We investigated the effects of language on vision by focusing on a well-known problem: the binding and maintenance of color-location conjunctions. Four-year-olds performed a task in which they saw a target (e.g., a split square, red on the left and green on the right) followed by a brief delay and then were asked to find the target in an array including the target, its reflection (e.g., red on the right and green on the left), and a square with a different geometric split. Errors were overwhelmingly reflections. This finding shows that the children failed to maintain color-location conjunctions. Performance improved when targets were accompanied by sentences specifying color and direction (e.g., "the red is on the left"), but not when the conjunction was highlighted using a nonlinguistic cue (e.g., flashing, pointing, changes in size), nor when sentences specified a nondirectional relationship (e.g., "the red is touching the green"). The relation between children's matching performance and their long-term knowledge of directional terms suggests two distinct mechanisms by which language can temporarily bridge delays, providing more stable representations.

In this paper, we present a case study that explores the nature and development of the mechanisms by which language interacts with and influences our ability to represent and retain information from one of our most important non-linguistic systems-- vision. In previous work (Dessalegn & Landau, 2008), we showed that 4 year-olds remembered conjunctions of visual features better when the visual target was accompanied by a sentence containing an asymmetric spatial predicate (e.g., the yellow is to the left of the black) but not when the visual target was accompanied by a sentence containing a novel noun (e.g., look at the dax) or a symmetric spatial predicate (e.g., the yellow is touching the black). In this paper, we extend these findings. In three experiments, 3, 4 and 6 year-olds were shown square blocks split in half by color vertically, horizontally or diagonally (e.g., yellow-left, black-right) and were asked to perform a delayed-matching task. We found that sentences containing spatial asymmetric predicates (e.g., the yellow is to the left of the black) and non-spatial asymmetric predicates (e.g., the yellow is prettier than the black) helped 4 year-olds, although not to the same extent. By contrast, 3 year-olds did not benefit from different linguistic instructions at all while 6 year-olds performed at ceiling in the task with or without the relevant sentences. Our findings suggest by age 4, the effects of language on non-linguistic tasks depend on highly abstract representations of the linguistic instructions and are momentary, seen only in the context of the task. We further speculate that language becomes more automatically engaged in nonlinguistic tasks over development.

To further understand the nature of the visual-spatial representations required for successful acquisition of written language skills, we investigated the written language abilities of two individuals with Williams syndrome (WS) a developmental genetic disorder in which the presence of severe visual-spatial developmental delays and deficits has been well established. Using a case study approach, we examined the relationship between reading achievement and general cognitive ability, phonological skills, and visual-spatial skills for the two individuals. We found that, despite the strong similarity between the two individuals in terms of their verbal and non-verbal cognitive abilities and their phonological abilities (as well as chronological age and educational opportunities), their reading and spelling abilities differed by more than 5 grade levels. We present evidence that the difference in written language performance was likely to be due to differences in the severity and nature of their visual-spatial impairment. Moreover, we show that specific difficulty processing the orientation of visual stimuli is related to the reading difficulties of one of the two individuals. These results underscore the contribution of visual-spatial abilities to the reading acquisition process and identify WS as a potential source of valuable information regarding the role of visual-spatial processing in reading development.