The "temporal processing deficit" hypothesis in dyslexia: new experimental evidence

The notion that developmental dyslexia may result from a general, nonspecific, defect in perceiving rapidly changing auditory signals is a current subject of debate (so-called "temporal processing deficit" hypothesis). Thirteen phonological dyslexics (age 10-13 years) and 10 controls matched for chronological and reading age were compared on a temporal order judgment (TOJ) task using the succession of two consonants (/p/-/s/) within a cluster. In order to test the relevance of the temporal deficit hypothesis, the task also included two additional conditions where either the two stimuli were artificially slowed or the interstimulus interval was expanded. As expected, the TOJ performance was significantly poorer in dyslexics than in controls. Moreover, in the "slowed speech" condition dyslexics' performance improved to reach the normal controls' level, whereas no significant improvement occurred when increasing the interstimulus interval. Finally dyslexics' performances, especially on the slowed condition, were found correlated with several tests of phonological processing (phoneme deletion, rhyme judgment, and nonword spelling tasks). These results lend support to the general temporal deficit theory of dyslexia.     

Timing recalibration in childhood Tourette syndrome associated with persistent pimozide treatment

In this study, we have tested the effects of the dopamine D₂ receptor blocker pimozide on timing performance in patients with Tourette syndrome (TS). Nine children with TS were tested off‐medication and following 3 months of daily treatment with pimozide. Subjects completed a time reproduction and a time production task using supra‐second temporal intervals. We show that pimozide improves motor timing performance by reducing the patients' variability in reproducing the duration of visual stimuli. On the other hand, this medication has no effect on the reproduction accuracy and on both variability and accuracy of the performance on the time production task. Our results suggest that pimozide might have improved motor timing variability as a result of its beneficial side effect on endogenous dopamine levels (i.e., normalization).     

“But Others Do It!”: Do Misperceptions of Schoolmate Alcohol and Marijuana Use Predict Subsequent Drug Use Among Young Adolescents?

We examined the effects of perceived prevalence of drug use among same-age peers on adolescents' subsequent drug use. In 7^th grade, participants estimated prevalence of alcohol and marijuana use among 7^th-grade students in their school, reported own use of these drugs, receipt of offers to use these drugs, and frequency of contact with peers who use these drugs. In 8^th grade, participants reported their frequency of alcohol and marijuana use. Although perceived prevalence of drug use predicted subsequent alcohol and marijuana use when controlling for actual prevalence, these effects disappeared once participants' prior levels of drug use and proximal peer contacts were considered. Implications of findings for intervention programs aiming solely to increase accuracy of perceived prevalence estimates are discussed.     

Marijuana use from adolescence to young adulthood: multiple developmental trajectories and their associated outcomes.

This study used latent growth mixture modeling to identify discrete developmental patterns of marijuana use from early adolescence (age 13) to young adulthood (age 23) among a sample of 5,833 individuals. After the a priori removal of abstainers, 4 trajectory groups were identified: early high users, who decreased from a relatively high level of use at age 13 to a more moderate level: stable light users, who maintained a low level of use: steady increasers, who consistently increased use; and occasional light users, who began use at age 14 and used at low levels thereafter. Analyses of covariance comparing the trajectory groups on behavioral, socioeconomic, and health outcomes at age 29 revealed that abstainers consistently had the most favorable outcomes, whereas early high users consistently had the least favorable outcomes.     

Perceptions of visible piercings: a pilot study

49 undergraduates were shown pictures of a man and a woman with piercings and with no piercings. The pierced model was judged to be less attractive and less normal than the nonpierced model. The pierced model was perceived as less intelligent, caring, generous, honest, and religious but more artistic and mysterious.     

Temporal and atemporal truth in intuitionistic mathematics

In section 1 we argue that the adoption of a tenseless notion of truth entails a realistic view of propositions and provability. This view, in turn, opens the way to the intelligibility of theclassical meaning of the logical constants, and consequently is incompatible with the antirealism of orthodox intuitionism. In section 2 we show how what we call the potential intuitionistic meaning of the logical constants can be defined, on the one hand, by means of the notion of atemporal provability and, on the other, by means of the operator K of epistemic logic. Intuitionistic logic, as reconstructed within this perspective, turns out to be a part of epistemic logic, so that it loses its traditional foundational role, antithetic to that of classical logic. In section 3 we uphold the view that certain consequences of the adoption of atemporal notion of truth, despite their apparent oddity, are quite acceptable from an antirealist point of view.     

Perceptual and linguistic interactions in speeded classification: tests of the semantic coding hypothesis

We tested the semantic coding hypothesis, which states that cross-modal interactions observed in speeded classification tasks arise after perceptual information is recoded into an abstract format common to perceptual and linguistic systems. Using a speeded classification task, we first confirmed the presence of congruence interactions between auditory pitch and visual lightness and observed Garner-type interference with nonlinguistic (perceptual) stimuli (low-frequency and high-frequency tones, black and white squares). Subsequently, we found that modifying the visual stimuli by (a) making them lexical (related words) or (b) reducing their compactness or figural 'goodness' altered congruence effects and Garner interference. The results are consistent with the semantic coding hypothesis, but only in part, and suggest the need for additional assumptions regarding the role of perceptual organization in cross-modal dimensional interactions.