Mathematical skill in individuals with Williams syndrome: evidence from a standardized mathematics battery

Williams syndrome (WS) is a developmental disorder associated with relatively spared verbal skills and severe visuospatial deficits. It has also been reported that individuals with WS are impaired at mathematics. We examined mathematical skills in persons with WS using the second edition of the Test of Early Mathematical Ability (TEMA-2), which measures a wide range of skills. We administered the TEMA-2 to 14 individuals with WS and 14 children matched individually for mental-age on the matrices subtest of the Kaufman Brief Intelligence Test. There were no differences between groups on the overall scores on the TEMA-2. However, an item-by-item analysis revealed group differences. Participants with WS performed more poorly than controls when reporting which of two numbers was closest to a target number, a task thought to utilize a mental number line subserved by the parietal lobe, consistent with previous evidence showing parietal abnormalities in people with WS. In contrast, people with WS performed better than the control group at reading numbers, suggesting that verbal math skills may be comparatively strong in WS. These findings add to evidence that components of mathematical knowledge may be differentially damaged in developmental disorders.     

Global dot integration in typically developing children and in Williams Syndrome

Williams Syndrome (WS) is a neurodevelopmental disorder that results in deficits in visuospatial perception and cognition. The dorsal stream vulnerability hypothesis in WS predicts that visual motion processes are more susceptible to damage than visual form processes. We asked WS participants and typically developing children to detect the global structure Glass patterns, under “static” and “dynamic” conditions in order to evaluate this hypothesis. Sequentially presented Glass patterns are coined as dynamic because they induce illusory motion, which is modeled after the interaction between orientation (form) and direction (motion) mechanisms. If the dorsal stream vulnerability holds in WS participants, then they should process real and illusory motion atypically. However, results are consistent with the idea that form and motion integration mechanisms are functionally delayed or attenuated in WS. Form coherence thresholds for both static and dynamic Glass patterns in WS were similar to those of 4–5 year old children, younger than what is predicted by mental age. Dynamic presentation of Glass patterns improved thresholds to the same degree as typical participants. Motion coherence thresholds in WS were similar to those of mental age matches. These data pose constraints on the dorsal vulnerability hypothesis, and refine our understanding of the relationship between form and motion processing in development.     

VIRTUES, SOCIAL ROLES, AND CONTEXTUALISM

Abstract: Contextualism in epistemology has been proposed both as a way to avoid skepticism and as an explanation for the variability found in our use of "knows." When we turn to contextualism to perform these two functions, we should ensure that the version we endorse is well suited for these tasks. I compare two versions of epistemic contextualism: attributor contextualism (from Keith DeRose) and methodological contextualism (from Michael Williams). I argue that methodological contextualism is superior both in its response to skepticism and in its mechanism for changing contexts. However, methodological contextualism still faces two challenges: explaining why we are solidly committed to some contexts, and explaining why knowledge within a context is valuable. I propose virtue contextualism as a useful extension of methodological contextualism, focusing on the way that our virtues depend on our social roles. My proposed virtue contextualism retains the benefits of methodological contextualism while explaining both our commitment to particular contexts and the value of knowledge held within those contexts.     

Arousal and memory: phasic measures of arousal in a free recall task.

EEG alpha activity and skin potential were monitored during word presentation in a single trial free recall task. Phasic changes in EEG alpha and skin potential, co-occurring with word onset, were positively related to recall at an immediate retention interval (2 min) but not after a delay (45 min). The results were interpreted as supporting the extension of Routtenberg's (1968) two-arousal system hypothesis to human memory. Arousal was viewed as affecting memory during the attribute encoding stage of memory storage.     

The development of contrast constancy

The mature visual system possesses mechanisms that enable invariant perception of the contrast of an object and its features as the object undergoes changes in distance. This phenomenon, which has been called contrast constancy, obtains at suprathreshold contrasts only. Some models of contrast constancy assume the presence of narrowband spatial-frequency channels. An implication of M.S. Banks, B.R. Stephens, and E.E. Hartmann (1985, Journal of Experimental Child Psychology, 40, 501-527) is that contrast constancy should not be observed at 6 weeks but may be observed at 12 weeks. We examined this implication by investigating the development of contrast constancy in 6- and 12-week-old infants. Two sine wave gratings, differing in spatial frequency by a factor of 3, were presented side-by-side. The contrast of one grating was varied in order to estimate the contrast at which preference for the two gratings was equal. The equal preference points for 6-week-olds were predictable from their contrast thresholds. The 12-week-olds' equal preference points for low-contrast stimuli were predictable from their contrast thresholds, but those for intermediate and high-contrast stimuli were not. Thus, if one accepts the assumption that equal preference in infants is analogous to apparent contrast matches in adults, these data imply that contrast constancy is observed at 12 weeks but not 6 weeks. The perceptual consequences of this developmental transition are discussed.     

The role of appraisal purpose: Effects of purpose on information acquisition and utilization

Past research on the role of appraisal purpose in the appraisal decision-making process has concentrated on the motivational role of purpose. Research has found that raters are less willing to give poor ratings when appraisals are to be used for some purposes rather than others. The present paper describes two experiments which explore how appraisal purpose might affect rater cognitive activities as well. The first experiment investigated how appraisal purpose and outcomes affect how raters differentially utilize information to make appraisal decisions. Few differences were found. The second experiment investigated how raters differentially search for performance information to make appraisal decisions for different purposes and outcomes. Raters were found to search for more comparative information when they had to select one of several ratees for some treatment. The results also indicated a discrepancy between how information is collected and how it is used. Implications for defining the role of purpose in the appraisal process, as well as for recent process approaches to performance appraisal, are discussed.     

Believing at Will is Possible

There are convincing counter-examples to the widely accepted thesis that we cannot believe at will. For it seems possible that the truth of a proposition depend on whether or not one believes it. I call such scenarios cases of Truth Depends on Belief (TDB) and I argue that they meet the main criteria for believing at will that we find in the literature. I reply to five objections that one might level against the thesis that TDB cases show that believing at will is possible, namely that (1) mind-reading is impossible, (2) in TDB cases, one's belief is caused by one's desire, (3) in TDB scenarios, one chooses not a belief but something else, (4) TDB cases are reducible to Feldman cases, and that (5) if truth depends on belief, we are on the road to a regress. Of course, TDB scenarios hardly, if ever, occur in real life. For three reasons, they are nonetheless important. First, they show that the thesis that it is conceptually impossible to believe at will is simply false. Second, they provide us with an important constraint on any version of the thesis that it is psychologically impossible to believe at will. Third, they show us that, contrary to what several philosophers claim or imply, believing at will should not be identified with believing irrespective of—what one considers to be—the truth, nor should believing irrespective of the truth be considered a necessary condition for believing at will.     

Situating Rhetorical Politics in Heidegger's Protopractical Ontology 1923–25: The French Occupy the Ruhr

Abstract

¹ 1 I am grateful to audiences at the University of California, Riverside, the Joint Session of the Aristotelian Society and Mind Association at the University of East Anglia, and at Dalhousie University for helpful questions. Sincere thanks go to two anonymous referees and the editors of this Journal. For written comments, detailed discussion and encouragement, I am particularly grateful to Duncan MacIntosh, Susan Sherwin, Richmond Campbell, Lorraine Code, Steven Burns, Guy Longworth, Gary Watson, Margaret Chapman and Guy Blanchard. This paper makes a preliminary case for a central and radical claim. I begin with Bernard Williams’ seldom-faced argument that integrity cannot be a moral virtue because it lacks two key ingredients of moral virtues, namely a characteristic thought and motivation. Whereas, for example, generosity involves the thought that another could use assistance, and the motivation to actually give assistance, integrity lacks these two things essential to morally excellent responses. I show that several maneuvers aimed at avoiding Williams’ challenge fail and that others are likely to remain unpersuasive. The paper concludes by offering an argument to the best explanation: Williams’ important insight is best explained by the supposition that integrity is an epistemic virtue, and an epistemic virtue of a practical sort.     

Everyday executive function in standard-risk acute lymphoblastic leukemia survivors

Although absolute pitch (AP) is a rare skill in typical development, individuals with Williams syndrome (WS) are often referred to as possessing this musical ability. However, there is paucity of research on the topic. In this article, 2 studies were conducted to evaluate AP in WS. In Study 1, seven musically trained individuals with WS, 14 musically trained typically developing controls matched for chronological age, and 2 experienced musicians with AP completed a pitch-identification task. Although the task was a classical assessment of AP, it required participants to have musical knowledge, and the availability and accessibility of musically trained individuals with WS is very low. In Study 2, a paradigm suitable for evaluating AP in individuals without musical training was used, which made it possible to evaluate a larger group of participants with WS. A pitch memory test for isolated tones was presented to 27 individuals with WS, 54 typically developing peers matched for chronological age, and the 2 musicians with AP. Both individuals with WS and their controls obtained low results in the two studies. They showed an arbitrary pattern of response, and their performance was far from that of musicians with AP. Therefore, participants with WS did not appear to possess AP. Unlike what is usually claimed, results suggest that AP is not a remarkable ability in WS and that, as in the typically developing population, this musical ability is also rare in individuals with WS.     

Self in time and language

Time has been considered a crucial factor in distinguishing between two levels of self-awareness: the “core,” or “minimal self,” and the “extended,” or “narrative self.” Herein, I focus on this last concept of the self and, in particular, on the relationship between the narrative self and language. In opposition to the claim that the narrative self is a linguistic construction, my idea is that it is created by the functioning of mental time travel, that is, the faculty of human beings to project themselves mentally backwards in time to relive, or forward to anticipate, events. Moreover, I propose that narrative language itself should be considered a product of a core brain network that includes mechanisms, such as mental time travel, mindreading, and visuo-spatial systems.