Impairment of auditory perception and language comprehension in dysphasia

Men with chronic focal brain wounds were examined for their ability to discriminate complex tones, synthesized steady-state vowels, and synthesized consonant—vowel syllables. Subjects with left hemisphere damage, but not right hemisphere damage, were impaired in their ability to respond correctly to rapidly changing acoustic stimuli, regardless of whether stimuli were verbal or nonverbal. The degree of impairment in auditory processing correlated highly with the degree of language comprehension impairment. The pattern of impairment of the group with left hemisphere damage on these perceptual tests was similar to that found in children with developmental language disorders.     

Keeping track of where we are: Spatial working memory in navigation

Spatial working memory (WM) seems to include two types of spatial information: locations and relations. However, this distinction has been based on small-scale tasks. Here, we used a virtual navigation paradigm to examine whether WM for locations and relations applies to the large-scale spatial world. We found that navigators who successfully learned two routes and also integrated them were superior at maintaining multiple locations and multiple relations in WM. However, over the entire spectrum of navigators, WM for spatial relations, but not locations, was specifically predictive of route integration performance. These results lend further support to the distinction between these two forms of spatial WM and point to their critical role in individual differences in navigation proficiency.     

Changes in reality monitoring and episodic memory in early childhood

The purposes of this research were to examine the developmental relation between reality monitoring and episodic memory, to link reality monitoring to autobiographical memory by using extended naturalistic events, and to examine prefrontal functioning as a potential contributor to development in reality monitoring and episodic memory. In Experiment 1, 4-year-olds were worse than 6- or 8-year-olds at reality monitoring after a week delay, despite the fact that they remembered more about real than imagined events and remembered different aspects of each. In Experiments 2 and 3, reality monitoring and episodic memory were evaluated for 4- and 6-year-olds immediately after the events occurred and, in Experiment 3, again after a week delay. Reality monitoring was at higher levels for both age groups, but age differences remained. These data suggest that preschoolers' difficulties with reality monitoring result from a combination of episodic memory deficits and strategic differences. In addition, correlation analyses more directly linked preschoolers' reality monitoring to episodic memory and supported the hypothesis that episodic memory development is related to prefrontal functioning.     

Whorf versus Socrates, round 10

A recent paper by Dehaene, Izard, Pica and Spelke examined geometric concepts among the Munduruku, an Amazonian group without many linguistic terms for spatial relations, and without maps or formal schooling. Their profile of strengths and weaknesses provides new insights into the nature of the human mind and the importance of culture and language to the development of thought.     

Preexisting knowledge versus on-line learning: what do young infants really know about spatial location?

Contemporary knowledge of infant cognition relies heavily on violation-of-expectation experiments. However, there are two ways to conceptualize what occurs in such studies. Babies may react to anomalous test events because of preexisting world knowledge. Alternatively, they may react because they have learned about events during the familiarization period. One way to distinguish these possibilities is to contrast familiarization with everyday versus anomalous events. In the studies we report here, we used this method to probe the nature of 5-month-olds' expectations about the locations of objects hidden in sand and later revealed. In Experiment 1, infants who initially saw everyday events did react to anomalous ones, as found previously, whereas infants who initially saw anomalous events did not react to everyday events. In Experiment 2, two alternative explanations of this pattern were ruled out. We conclude that by the age of 5 months, infants have expectations regarding the location of objects in continuous space.     

Socioeconomic status modifies the sex difference in spatial skill

We examined whether the male spatial advantage varies across children from different socioeconomic (SES) groups. In a longitudinal study, children were administered two spatial tasks requiring mental transformations and a syntax comprehension task in the fall and spring of second and third grades. Boys from middle- and high-SES backgrounds outperformed their female counterparts on both spatial tasks, whereas boys and girls from a low-SES group did not differ in their performance level on these tasks. As expected, no sex differences were found on the verbal comprehension task. Prior studies have generally been based on the assumption that the male spatial advantage reflects ability differences in the population as a whole. Our finding that the advantage is sensitive to variations in SES provides a challenge to this assumption, and has implications for a successful explanation of the sex-related difference in spatial skill.     

How Important Is the Digital Divide? The Relation of Computer and Videogame Usage to Gender Differences in Mental Rotation Ability

Researchers interested in the associations of gender with spatial experience and spatial ability have not yet focused on several activities that have become common in the modern digital age. In this study, using a new questionnaire called the Survey of Spatial Representation and Activities (SSRA), we examined spatial experiences with computers and videogames in a sample of nearly 1,300 undergraduate students. Large gender differences, which favored men, were found in computer experience. Although men and women also differed on SAT scores, gender differences in computer experience were still apparent with SAT factored out. Furthermore, men and women with high and low levels of computer experience, who were selected for more intensive study, were found to differ significantly on the Mental Rotations Test (MRT). Path analyses showed that computer experience substantially mediates the gender difference in spatial ability observed on the MRT. These results collectively suggest that the “Digital Divide” is an important phenomenon and that encouraging women and girls to gain spatial experiences, such as computer usage, might help to bridge the gap in spatial ability between the sexes.     

Five reasons to doubt the existence of a geometric module

It is frequently claimed that the human mind is organized in a modular fashion, a hypothesis linked historically, though not inevitably, to the claim that many aspects of the human mind are innately specified. A specific instance of this line of thought is the proposal of an innately specified geometric module for human reorientation. From a massive modularity position, the reorientation module would be one of a large number that organized the mind. From the core knowledge position, the reorientation module is one of five innate and encapsulated modules that can later be supplemented by use of human language. In this paper, we marshall five lines of evidence that cast doubt on the geometric module hypothesis, unfolded in a series of reasons: (1) Language does not play a necessary role in the integration of feature and geometric cues, although it can be helpful. (2) A model of reorientation requires flexibility to explain variable phenomena. (3) Experience matters over short and long periods. (4) Features are used for true reorientation. (5) The nature of geometric information is not as yet clearly specified. In the final section, we review recent theoretical approaches to the known reorientation phenomena.     

Seeing Like a Geologist: Bayesian Use of Expert Categories in Location Memory

Memory for spatial location is typically biased, with errors trending toward the center of a surrounding region. According to the category adjustment model (CAM), this bias reflects the optimal, Bayesian combination of fine‐grained and categorical representations of a location. However, there is disagreement about whether categories are malleable. For instance, can categories be redefined based on expert‐level conceptual knowledge? Furthermore, if expert knowledge is used, does it dominate other information sources, or is it used adaptively so as to minimize overall error, as predicted by a Bayesian framework? We address these questions using images of geological interest. The participants were experts in structural geology, organic chemistry, or English literature. Our data indicate that expertise‐based categories influence estimates of location memory—particularly when these categories better constrain errors than alternative (“novice”) categories. Results are discussed with respect to the CAM.     

A slippery directional slope: Individual differences in using slope as a directional cue

Navigators rely on many different types of cues to build representations of large-scale spaces. Sloped terrain is an important cue that has received recent attention in comparative and human spatial research. However, the studies to date have been unable to determine how directional slope information leads to more accurate spatial representations. Moreover, whereas some studies have shown that the inclusion of slope cues improves performance on spatial tasks across participants (Kelly, 2011; Restat, Steck, Mochnatzki, & Mallot, 2004), other research has suggested individual differences in the benefits of slope cues (Chai & Jacobs, 2010; Nardi, Newcombe, & Shipley, 2011). We sought to clarify the role of sloped terrain in improving the representation of large-scale environments. In Experiment 1, participants learned the layout of buildings in one of two desktop virtual environments: either a directionally sloped terrain or a completely flat one. Participants in the sloped environment outperformed those in the flat environment. However, participants used slope information as an additional cue, rather than as a preferred reference direction. In Experiment 2, the two virtual environments were again either flat or sloped, but we increased the complexity of the relations between the slope and the path. In this experiment, better performance in the sloped environment was only seen for participants with good self-reported senses of direction. Taken together, the studies show that slope provides useful information for building environmental representations in simple cases, but that individual differences emerge in more complex situations. We suggest that good and bad navigators use different navigational strategies.