The effect of pictorial depth information on projected size judgments.

When full depth cues are available, size judgments are dominated by physical size. However, with reduced depth cues, size judgments are influenced less by physical size and more by projected size. By manipulating monocularly presented pictorial depth cues only, in this study we reduced depth cues further than had previous size judgment studies. Participants were presented monocularly with two shapes against a background of zero (control), one, two, or three pictorial depth cues. Each cue was added progressively in the following order: height in the visual field, linear perspective, and texture gradient. Participants made a same/different judgment regarding the projected size of the two shapes (i.e., ignoring any depth cues). As was expected, accuracy increased and response times decreased as the ratio between the projected size of the two shapes increased (range of projected size ratios, 1:1-1:5). In addition, with the exception of the larger size ratios (1:4 and 1:5), detection of projected size difference grew poorer as depth cues were added. One- and two-cue conditions had the most weighting in this performance decrement, with little weighting from the three-cue condition. We conclude that even minimal depth information is difficult to inhibit, which indicates that depth perception requires little focused attention

Genetic contributions to visuospatial cognition in Williams syndrome: insights from two contrasting partial deletion patients

Background Williams syndrome (WS) is a rare neurodevelopmental disorder arising from a hemizygotic deletion of approximately 27 genes on chromosome 7, at locus 7q11.23. WS is characterised by an uneven cognitive profile, with serious deficits in visuospatial tasks in comparison to relatively proficient performance in some other cognitive domains such as language and face processing. Individuals with partial genetic deletions within the WS critical region (WSCR) have provided insights into the contribution of specific genes to this complex phenotype. However, the combinatorial effects of different genes remain elusive. Methods We report on visuospatial cognition in two individuals with contrasting partial deletions in the WSCR: one female (HR), aged 11 years 9 months, with haploinsufficiency for 24 of the WS genes (up to GTF2IRD1), and one male (JB), aged 14 years 2 months, with the three most telomeric genes within the WSCR deleted, or partially deleted. Results Our in-depth phenotyping of the visuospatial domain from table-top psychometric, and small- and large-scale experimental tasks reveal a profile in HR in line with typically developing controls, albeit with some atypical features. These data are contrasted with patient JB’s atypical profile of strengths and weaknesses across the visuospatial domain, as well as with more substantial visuospatial deficits in individuals with the full WS deletion. Conclusions Our findings point to the contribution of specific genes to spatial processing difficulties associated with WS, highlighting the multifaceted nature of spatial cognition and the divergent effects of genetic deletions within the WSCR on different components of visuospatial ability. The importance of general transcription factors at the telomeric end of the WSCR, and their combinatorial effects on the WS visuospatial phenotype are also discussed

The Kuramoto model: A simple paradigm for synchronization phenomena

Synchronization phenomena in large populations of interacting elements are the subject of intense research efforts in physical, biological, chemical, and social systems. A successful approach to the problem of synchronization consists of modeling each member of the population as a phase oscillator. In this review, synchronization is analyzed in one of the most representative models of coupled phase oscillators, the Kuramoto model. A rigorous mathematical treatment, specific numerical methods, and many variations and extensions of the original model that have appeared in the last few years are presented. Relevant applications of the model in different contexts are also included

Stroke Caregiver Outcomes from the Telephone Assessment and Skill-Building Kit (TASK)

Purpose: Stroke caregivers often express the need for information about stroke and assistance with stroke-related care in the early discharge period. The Telephone Assessment and Skill-Building Kit (TASK) is an 8-week program that addresses caregiver needs. This study explored the efficacy of the TASK program in improving stroke caregiver outcomes. Method: Guided by a conceptual model, 6 outcomes (optimism, task difficulty, threat appraisal, depressive symptoms, life changes, general health perceptions) were measured in 40 caregivers randomized to the TASK (n = 21) or an attention control group (n = 19). Data were analyzed using analysis of covariance (ANCOVA), controlling for baseline scores and minutes spent with the nurse. Results: Significant increases in optimism at 4 weeks, 8 weeks, and 12 weeks were found, with medium effect sizes for the TASK group relative to the control group (p < .05). Significant improvements in task difficulty at 4 weeks, and threat appraisal at both 8 weeks and 12 weeks were also found (p < .05). Conclusion: Caregivers receiving the TASK intervention improved in optimism, task difficulty, and threat appraisal. Further testing of an enhanced version of the TASK program is warranted, with attention directed toward more distal stroke caregiver outcomes

Using a mixture of cottonseed hulls and cottonseed meal to replace alfalfa hay in diets for stressed feeder calves

One 28-day receiving experiment was conducted using 625 exotic × British cross heifers to evaluate growth performance and morbidity on receiving diets that contained either alfalfa hay or a pellet composed of 65% cottonseed hulls and 35% cottonseed meal as the roughage source. Heifers fed the cotton byproduct pellet consumed more feed (P<0.01) but tended to be less efficient than those fed alfalfa hay. Daily gain was comparable between diets (P>0.05), and the percentages of heifers diagnosed, treated, or retreated for respiratory disease were similar