The gap between rod and frame influences the rod-and-frame effect with small and large inducing displays

The role of the spatial separation between the ends of a rod and a frame’s inner edge (gap) in modulating the rod-and-frame effect (RFE) has been studied here with frames subtending either large or small retinal angles. With a large frame, rod settings were always in the direction of frame tilt (direct effects) and varied inversely with gap size. With a small frame, rod settings were in the direction of frame tilt for tilts between 7.5° and 15°; with larger frame tilts, rod settings in the direction opposite that of the frame were observed (indirect effects). Increasing gap size produced a tendency toward negativity (away from frame tilt). Consequently, direct effects were larger for small gaps, while the opposite was true for indirect effects. Overall, these results point to the importance of gap size in modulating the RFE, for both large and small displays.     

Local and global visual mechanisms underlying individual differences in the rod-and-frame illusion

The role of local and global visual mechanisms in individual differences in the rod-and-frame (RF) effect was investigated. Field-dependent and field-independent observers, selected on the basis of Witkin and Asch’s (1948) classical procedure, were submitted to the small RF test (Coren & Hoy, 1986). Four frame tilts and two gap sizes were used. As expected, direct effects (i.e., rod settings in the direction of frame tilt) were observed at small degrees of frame tilt, while indirect effects (i.e., rod settings in the direction opposite that of frame tilt) were observed at larger frame tilts. Fielddependent observers showed larger direct effects in the case of the small gap. Indirect effects were comparable in both field-dependent and field-independent subjects, regardless of gap size. Following the model proposed by Wenderoth and Johnstone (1987), these findings indicate that low-level visual mechanisms, responsible for local orientation interactions, have a different gain in fielddependent and field-independent individuals. In contrast, global visual mechanisms, presumably acting     

The time course of attentional focusing in dyslexic and normally reading children

A cue size procedure was used to evaluate the time course of visuo-spatial attention in dyslexic and normally reading children. When a stimulus target is presented inside a large cue vs a small cue the identification time is slower. In the present study two cue-target delays (100 and 500 ms) were used. Results showed a slower time course of attentional focusing in dyslexics vs normal readers. Indeed, dyslexics exhibited no cue size effect at a shorter cue-target delay (100 ms), while it was present at a longer cue-target delay (500 ms). In contrast, a cue size effect was found at both cue-target delays in normally reading children. These results further support the hypothesis of sluggish automatic focusing of visual attention in dyslexics. This impairment could be a consequence of a general magnocellular deficit demonstrated previously in dyslexics.     

Theories of Types and Names with Positive Stratified Comprehension

We introduce a certain extension of -calculus, and show that it has the Church-Rosser property. The associated open-term extensional combinatory algebra is used as a basis to construct models for theories of Explict Mathematics (formulated in the language of "types and names") with positive stratified comprehension. In such models, types are interpreted as collections of solutions (of terms) w.r. to a set of numerals. Exploiting extensionality, we prove some consistency results for special ontological axioms which are refutable under elementary comprehension.     

Multiple stimulus presentation yields larger deficits in children with developmental dyslexia: A study with reading and RAN-type tasks

In this study, we examined the effect of multiple versus single stimulus presentation in typically developing readers and children with developmental dyslexia. The tasks involved either reading single words or arrays of words or naming single or multiple colors and digits (rapid automatized naming or RAN). To be able to compare these sets of conditions, we recorded total response times (i.e., the time between stimulus onset and the end of the participant’s vocal response) in all cases. The study included 43 typically developing readers and 25 children with dyslexia.

Results indicate that typically developing readers have a clear advantage with multiple over single items on both RAN and reading tasks. The children with dyslexia showed a moderate advantage for multiple stimuli in naming colors and digits but presented the opposite pattern in reading.

With regard to reading, the disproportionate impairment of the children with dyslexia in dealing with multiple arrays suggests difficulty in integrating the multiple subcomponents of the reading task over and above the basic nuclear deficit in decoding words. Regarding the RAN tasks, results confirm that the requirement of integrating multiple subcomponents may be critical in mediating the predictive value of these measures on reading.     

Contemporary Philosophy of Science in Italy: An Overview

The paper analyses the development of some themes in the contemporary philosophy of science in Italy. Section 1 reviews the dabate on the legacy of neopositivism. The spread of the philosophy of Popper is outlined in Section 2, with particular regard to the problem of the vindication of induction. Section 3 deals with the debate on the incommensurability thesis, while Section 4 examines its consequences on the possible relationships between historical and epistemological studies of science. The last section is devoted to one of the most recent trends in the Italian philosophy of science: the resumption of Aristotelian dialectics. This revised version was published online in August 2006 with corrections to the Cover Date.     

Depression, Anxiety and Anger in Subtypes of Irritable Bowel Syndrome Patients

The present study aimed to elucidate the differences in depression, anxiety, anger, and quality of life in a sample of non-psychiatric IBS patients, starting from the hypothesis that IBS subtypes may have different symptomatic expressions of negative emotions with different outcomes on quality of life measures. Forty-two constipation-predominant IBS (C-IBS) subjects and 44 diarrhea-predominant IBS (D-IBS) subjects, after an examination by a gastroenterologist and a total colonoscopy, underwent a clinical interview and psychometric examination for the assessment of depression, anxiety, anger and quality of life. IBS subtypes showed different symptomatic profiles in depression, anxiety and anger, with C-IBS patients more psychologically distressed than D-IBS subjects. Affective and emotional symptoms should be considered as specific and integral to the syndrome, and recognizing the differences between IBS subtypes may have relevant implications for treatment options and clinical outcome.     

Morpheme-based reading aloud: evidence from dyslexic and skilled Italian readers

The role of morphology in reading aloud was examined measuring naming latencies to pseudowords and words composed of morphemes (roots and derivational suffixes) and corresponding simple pseudowords and words. Three groups of Italian children of different ages and reading abilities, including dyslexic children, as well as one group of adult readers participated in the study. All four groups read faster and more accurately pseudowords composed of root and suffix than simple pseudowords (Experiment 1). Unlike skilled young and adult readers, both dyslexics and younger children benefited from morphological structure also in reading aloud words (Experiment 2). It is proposed that the morpheme is a unit of intermediate grain size that proves useful in processing all linguistic stimuli, including words, in individuals with limited reading ability (dyslexics and younger readers) who did not fully develop mastering of whole-word processing. For skilled readers, morphemic parsing is useful for reading those stimuli (i.e., pseudowords made up of morphemes), for which a whole-word lexical unit does not exist; where such whole-word lexical units do exist, skilled readers do not need to rely on morphological parsing because they can rely on a lexical (whole-word) reading unit that is larger than the morpheme.