Volume 51, Issue 7-8, Pages 639-896(July 2003)
Preface
Preface
NASA Astrophysics Data System (ADS)
Andreev, O.
2003-07-01
We briefly review a possible scheme for getting the known QCD scaling laws within string theory. In particular, we consider amplitudes for exclusive scattering of hadrons at large momentum transfer and hadronic form factors.
Kristensen, Hanne; Oerbeck, Beate
2006-01-01
Our main aim in this study was to explore the association between selective mutism (SM) and aspects of nonverbal cognition such as visual memory span and visual memory. Auditory-verbal memory span was also examined. The etiology of SM is unclear, and it probably represents a heterogeneous condition. SM is associated with language impairment, but nonspecific neurodevelopmental factors, including motor problems, are also reported in SM without language impairment. Furthermore, SM is described in Asperger's syndrome. Studies on nonverbal cognition in SM thus merit further investigation. Neuropsychological tests were administered to a clinical sample of 32 children and adolescents with SM (ages 6-17 years, 14 boys and 18 girls) and 62 nonreferred controls matched for age, gender, and socioeconomic status. We used independent t-tests to compare groups with regard to auditory-verbal memory span, visual memory span, and visual memory (Benton Visual Retention Test), and employed linear regression analysis to study the impact of SM on visual memory, controlling for IQ and measures of language and motor function. The SM group differed from controls on auditory-verbal memory span but not on visual memory span. Controlled for IQ, language, and motor function, the SM group did not differ from controls on visual memory. Motor function was the strongest predictor of visual memory performance. SM does not appear to be associated with deficits in visual memory span or visual memory. The reduced auditory-verbal memory span supports the association between SM and language impairment. More comprehensive neuropsychological studies are needed.
Yang, Cheng-Chang; Kao, Chen-Jay; Cheng, Ting-Wen; Yang, Chi-Cheng; Wang, Wei-Han; Yu, Rwei-Ling; Hsu, Yen-Hsuan; Hua, Mau-Sun
2012-12-01
Suppressed Digit Span performance has been proposed as an embedded indicator for suboptimal effort detection in neuropsychological evaluations in Western societies, particularly in the USA. However, its effectiveness in Chinese countries remains unexplored. The purposes of this study were first to explore normative Digit Span performance patterns between the Taiwan and American standardization samples, then to examine performances of patients with traumatic brain injury and with psychiatric diseases on the embedded measures (the Digit Span Scaled Score, Vocabulary minus Digit Span difference score, Reliable Digit Span, and the longest string of digits forward and backward) through retrospective data analysis. The normative Digit Span performance differs between the two cultural populations. Although litigating and nonlitigating participants perform differently on these measures, further prospective studies are needed to explore this issue with comprehensive external corroborating validity data.
Functional roles of the cingulo-frontal network in performance on working memory.
Kondo, Hirohito; Morishita, Masanao; Osaka, Naoyuki; Osaka, Mariko; Fukuyama, Hidenao; Shibasaki, Hiroshi
2004-01-01
We examined the relationship between brain activities and task performance on working memory. A large-scale study was initially administered to identify good and poor performers using the operation span and reading span tasks. On the basis of those span scores, we divided 20 consenting participants into high- and low-span groups. In an fMRI study, the participants performed verification of arithmetic problems and retention of target words either concurrently or separately. The behavioral results showed that performance was better in the high-span group than in the low-span group under a dual-task condition, but not under two single-task conditions. The anterior cingulate cortex (ACC), left prefrontal cortex (PFC), left inferior frontal cortex, and bilateral parietal cortex were primarily activated for both span groups. We found that signal changes in the ACC were greater in the high-span group than in the low-span group under the dual-task condition, but not under the single-task conditions. Structural equation modeling indicated that an estimate of effective connectivity from the ACC to the left PFC was positive for the high-span group and negative for the-low span group, suggesting that closer cooperation between the two brain regions was strongly related to working memory performance. We conclude that central executive functioning for attention shifting is modulated by the cingulo-frontal network.
Successful decoding of famous faces in the fusiform face area.
Axelrod, Vadim; Yovel, Galit
2015-01-01
What are the neural mechanisms of face recognition? It is believed that the network of face-selective areas, which spans the occipital, temporal, and frontal cortices, is important in face recognition. A number of previous studies indeed reported that face identity could be discriminated based on patterns of multivoxel activity in the fusiform face area and the anterior temporal lobe. However, given the difficulty in localizing the face-selective area in the anterior temporal lobe, its role in face recognition is still unknown. Furthermore, previous studies limited their analysis to occipito-temporal regions without testing identity decoding in more anterior face-selective regions, such as the amygdala and prefrontal cortex. In the current high-resolution functional Magnetic Resonance Imaging study, we systematically examined the decoding of the identity of famous faces in the temporo-frontal network of face-selective and adjacent non-face-selective regions. A special focus has been put on the face-area in the anterior temporal lobe, which was reliably localized using an optimized scanning protocol. We found that face-identity could be discriminated above chance level only in the fusiform face area. Our results corroborate the role of the fusiform face area in face recognition. Future studies are needed to further explore the role of the more recently discovered anterior face-selective areas in face recognition.
19. Jack E, Boucher, Photographer, May 1974. CLOSEUP DETAIL VIEW ...
19. Jack E, Boucher, Photographer, May 1974. CLOSE-UP DETAIL VIEW OF PAULI-LENTICULAR TRUSS SYSTEM, CENTRAL AREA. - Smithfield Street Bridge, Spanning Monongahela River on Smithfield Street, Pittsburgh, Allegheny County, PA
20. Jack E. Boucher, Photogtapher, May 1974. CLOSEUP VIEW OF ...
20. Jack E. Boucher, Photogtapher, May 1974. CLOSE-UP VIEW OF PAULI-LENTICULAR TRUSS SYSTEM, CENTRAL AREA. - Smithfield Street Bridge, Spanning Monongahela River on Smithfield Street, Pittsburgh, Allegheny County, PA
Working memory effects of gap-predictions in normal adults: an event-related potentials study.
Hestvik, Arild; Bradley, Evan; Bradley, Catherine
2012-12-01
The current study examined the relationship between verbal memory span and the latency with which a filler-gap dependency is constructed. A previous behavioral study found that low span listeners did not exhibit antecedent reactivation at gap sites in relative clauses, in comparison to high verbal memory span subjects (Roberts et al. in J Psycholinguist Res 36(2):175-188, 2007), which suggests that low span subjects are delayed at gap filling. This possibility was examined in the current study. Using an event-related potentials paradigm, it was found that low span subjects have an onset latency delay of about 200 ms in brain responses to violations of syntactic expectancies after the gap site, thus providing a time course measure of the delay hypothesized by previous literature.
Effects of leadership and span of control on nurses' job satisfaction and patient satisfaction.
McCutcheon, Amy Sanchez; Doran, Diane; Evans, Martin; Hall, Linda McGillis; Pringle, Dorothy
2009-01-01
Hospital restructuring has resulted in nurse managers' having direct responsibility for a greatly expanded number of units and staff. However, very little research has examined the impact of these larger spans of control on nurse and patient outcomes. This study examined the relationships between leadership style, span of control, nurses' job satisfaction and patient satisfaction, as well as the moderating effect of span of control on the relationship between leadership style and the two outcomes. The study was conducted at seven teaching and community hospitals with a sample of 51 units, 41 nurse managers, 717 nurses and 680 patients. Data analyses included multiple regression and hierarchical linear modelling. The study findings provided support for the theoretical relationships among leadership style, span of control, nurse job satisfaction and patient satisfaction. In addition, the results showed that higher spans of control decreased the positive effects of transformational and transactional leadership styles on job satisfaction and patient satisfaction, and increased the negative effects of management by exception and laissez-faire leadership styles on job satisfaction. Leadership matters, and certain leadership styles, particularly transformational, are better than others. Span of control also matters: the wider the span, the lower the nurses' job satisfaction and patient satisfaction. However, as spans of control increase in size, no leadership style, even transformational, can overcome the negative effects.
The composite complex span: French validation of a short working memory task.
Gonthier, Corentin; Thomassin, Noémylle; Roulin, Jean-Luc
2016-03-01
Most studies in individual differences in the field of working memory research use complex span tasks to measure working memory capacity. Various complex span tasks based on different materials have been developed, and these tasks have proven both reliable and valid; several complex span tasks are often combined to provide a domain-general estimate of working memory capacity with even better psychometric properties. The present work sought to address two issues. Firstly, having participants perform several full-length complex span tasks in succession makes for a long and tedious procedure. Secondly, few complex span tasks have been translated and validated in French. We constructed a French working memory task labeled the Composite Complex Span (CCS). The CCS includes shortened versions of three classic complex span tasks: the reading span, symmetry span, and operation span. We assessed the psychometric properties of the CCS, including test-retest reliability and convergent validity, with Raven's Advanced Progressive Matrices and with an alpha span task; the CCS demonstrated satisfying qualities in a sample of 1,093 participants. This work provides evidence that shorter versions of classic complex span tasks can yield valid working memory estimates. The materials and normative data for the CCS are also included.
Developmental dyslexia: the visual attention span deficit hypothesis.
Bosse, Marie-Line; Tainturier, Marie Josèphe; Valdois, Sylviane
2007-08-01
The visual attention (VA) span is defined as the amount of distinct visual elements which can be processed in parallel in a multi-element array. Both recent empirical data and theoretical accounts suggest that a VA span deficit might contribute to developmental dyslexia, independently of a phonological disorder. In this study, this hypothesis was assessed in two large samples of French and British dyslexic children whose performance was compared to that of chronological-age matched control children. Results of the French study show that the VA span capacities account for a substantial amount of unique variance in reading, as do phonological skills. The British study replicates this finding and further reveals that the contribution of the VA span to reading performance remains even after controlling IQ, verbal fluency, vocabulary and single letter identification skills, in addition to phoneme awareness. In both studies, most dyslexic children exhibit a selective phonological or VA span disorder. Overall, these findings support a multi-factorial view of developmental dyslexia. In many cases, developmental reading disorders do not seem to be due to phonological disorders. We propose that a VA span deficit is a likely alternative underlying cognitive deficit in dyslexia.
19. WHEELPIT AREA OF 1814 MILL WHERE JACOB PERKINS BREASTWHEEL ...
19. WHEELPIT AREA OF 1814 MILL WHERE JACOB PERKINS BREASTWHEEL WAS INSTALLED AND CONTROLLED BY PAUL MOODY FLYBALL GOVERNOR, LOOKING NORTH, WITH WEST (UPSTREAM) WALL AT LEFT. EXTRA HEAVY LONGITUDINAL BEAMS ORIGINALLY SPANNED WHEELPIT AREA WITHOUT INTERNAL SUPPORTS (METAL COLUMNS IN PHOTO ARE A RECENT ADDITION). EVIDENCE OF HEADRACE ENTRANCE ARCH HAS BEEN OBLITERATED BY CONCRETE RETAINING WALL AT REAR. - Boston Manufacturing Company, 144-190 Moody Street, Waltham, Middlesex County, MA
Effect of pattern complexity on the visual span for Chinese and alphabet characters
Wang, Hui; He, Xuanzi; Legge, Gordon E.
2014-01-01
The visual span for reading is the number of letters that can be recognized without moving the eyes and is hypothesized to impose a sensory limitation on reading speed. Factors affecting the size of the visual span have been studied using alphabet letters. There may be common constraints applying to recognition of other scripts. The aim of this study was to extend the concept of the visual span to Chinese characters and to examine the effect of the greater complexity of these characters. We measured visual spans for Chinese characters and alphabet letters in the central vision of bilingual subjects. Perimetric complexity was used as a metric to quantify the pattern complexity of binary character images. The visual span tests were conducted with four sets of stimuli differing in complexity—lowercase alphabet letters and three groups of Chinese characters. We found that the size of visual spans decreased with increasing complexity, ranging from 10.5 characters for alphabet letters to 4.5 characters for the most complex Chinese characters studied. A decomposition analysis revealed that crowding was the dominant factor limiting the size of the visual span, and the amount of crowding increased with complexity. Errors in the spatial arrangement of characters (mislocations) had a secondary effect. We conclude that pattern complexity has a major effect on the size of the visual span, mediated in large part by crowding. Measuring the visual span for Chinese characters is likely to have high relevance to understanding visual constraints on Chinese reading performance. PMID:24993020
Effects of a cochlear implant simulation on immediate memory in normal-hearing adults
Burkholder, Rose A.; Pisoni, David B.; Svirsky, Mario A.
2012-01-01
This study assessed the effects of stimulus misidentification and memory processing errors on immediate memory span in 25 normal-hearing adults exposed to degraded auditory input simulating signals provided by a cochlear implant. The identification accuracy of degraded digits in isolation was measured before digit span testing. Forward and backward digit spans were shorter when digits were degraded than when they were normal. Participants’ normal digit spans and their accuracy in identifying isolated digits were used to predict digit spans in the degraded speech condition. The observed digit spans in degraded conditions did not differ significantly from predicted digit spans. This suggests that the decrease in memory span is related primarily to misidentification of digits rather than memory processing errors related to cognitive load. These findings provide complementary information to earlier research on auditory memory span of listeners exposed to degraded speech either experimentally or as a consequence of a hearing-impairment. PMID:16317807
Emotional Egocentricity Bias Across the Life-Span.
Riva, Federica; Triscoli, Chantal; Lamm, Claus; Carnaghi, Andrea; Silani, Giorgia
2016-01-01
In our daily lives, we often have to quickly estimate the emotions of our conspecifics in order to have successful social interactions. While this estimation process seems quite easy when we are ourselves in a neutral or equivalent emotional state, it has recently been shown that in case of incongruent emotional states between ourselves and the others, our judgments can be biased. This phenomenon, introduced to the literature with the term Emotional Egocentricity Bias (EEB), has been found to occur in young adults and, to a greater extent, in children. However, how the EEB changes across the life-span from adolescence to old age has been largely unexplored. In this study, we recruited 114 female participants subdivided in four cohorts (adolescents, young adults, middle-aged adults, older adults) to examine EEB age-related changes. Participants were administered with a recently developed paradigm which, by making use of visuo-tactile stimulation that elicits conflicting feelings in paired participants, allows the valid and reliable exploration of the EEB. Results highlighted a U-shape relation between age and EEB, revealing enhanced emotional egocentricity in adolescents and older adults compared to young and middle-aged adults. These results are in line with the neuroscientific literature which has recently shown that overcoming the EEB is associated with a greater activation of a portion of the parietal lobe, namely the right Supramarginal Gyrus (rSMG). This is an area that reaches full maturation by the end of adolescence and goes through an early decay. Thus, the age-related changes of the EEB could be possibly due to the life-span development of the rSMG. This study is the first one to show the quadratic relation between age and the EEB and set a milestone for further research exploring the neural correlates of the life-span development of the EEB. Future studies are needed in order to generalize these results to the male population and to explore gender differences related to the aging of socio- emotional processes.
Studies of the Effects of Control Bandwidth and Dark-Hole Size on the HCIT Contrast Performance
NASA Technical Reports Server (NTRS)
Sidick, Erkin; Shaklan, Stuart; Balasubramanian, Kunjithapatha; Cady, Eric
2015-01-01
We have carried out both theoretical and experimental studies of the sensitivity of dark hole contrast to the control bandwidth and dark-hole dimensions in high-contrast broadband stellar coronagraphy. We have evaluated the performance of DM actuator solutions in the presence of occulting mask defects using one to five 2% -wide bands spanning a 10% bandpass. We have also investigated the dependence of the HCIT contrast performance on the size of dark -hole area including large dark holes formed at the Nyquist limit of the DM.
