Change blindness. Influence of scene content and emotional valence on change detection performance in clinical and not clinical children

Change-blindness (CB) occurs when large changes are missed under natural viewing conditions because they occur simultaneously with a brief visual disruption, like an eye movement, a blank screen, an ocular blink, or a camera cut in a film sequence. In the typical CB paradigm, the flicker task, pictures of daily life scenes are used to assess visual search efficiency (Rensink, 2000). Two versions of a picture are presented. The pictures are identical except in a specific detail. The pictures alternate repeatedly and are separated by a brief gray screen. The observers have to search the scene for what has changed between the two pictures until they detect it. As the task uses pictures of natural scenes, participants tend to give priority to some areas of the scene than to others. Consequently, they detect changes in objects of central interest (CI) faster than changes in marginal interest (MI) objects (Rensink et al. 1997). Both perceptual and semantic characteristics of the visual scene might be taken to create a sort of priority list that determines which items are going to be attended first. Changes in objects of CI pop out from the pictures, and they are usually efficiently detected. Changes in objects of MI are more difficult to detect and require serial visual search, and therefore performance is less efficient. This study aims to evaluate the visual search ability in tipically developing children and in children with psychiatric disorders. In Experiment 1, 52 healthy children and 22 adults executed the flicker task with IAPS emotional pictures. The valence of the images interferes with the attentional performance showing slower RT in detecting changes in front of emotional images. In particular, the negative pictures interfere more the CI detection, whereas the positive ones interfere more the MI detection. The results are discussed in term of biological VS motivational aspects. We hypothesize that the evolutionary role of the negative stimuli makes to interfere the attentional performance during the more automatic CI change. In contrast, the positive images interfere it through a more voluntary mechanism; the likeness of the stimuli makes the partecipants look at the picture rather than search for the change. In experiment 2, 14 children with a disorder of the autistic spectrum and 14 controls executed the same task of Experiment 1. Our results show that autistic children are slower than controls only in the MI detection. Furthermore, they differ from controls when detecting CI changes in front of negative picture and when detecting MI changes in front of positive pictures. Our results confirm the Fletcher-Watson et al’s results suggesting an impairment in the disengagement from the most rilevant items or, in alternative, in the orienting of attention. In Experiment 3, 75 healthy children and 19 adults executed the flicker task with pictures rated as appealing or unappealing. The appealingness of the images interferes with the attentional performance showing slower RT only when detecting MI change. The results are discussed in term of motivational aspects. We hypothesize that the appealingness of the stimuli interfere with the attentional performance obstructing the execution of the task. In experiment 4, 18 children with ADHD and 18 controls executed the same task of Experiment 1. Our results show that children with are overall slower than controls. Furthermore, they specifically differ from controls when detecting MI changes. The slower RT and the poor accuracy of children with ADHD on the highest demanding condition (e.g., detection of MI changes) is consistent with a deficit in attentional resources, or with a specific impairment in using serial top-down strategies due to their limited attentional resources. Overall, our results of the present study replicate the findings consistently observed with the flicker task (Fletcher-Watson, Collis, Findlay, & Leekam, 2009), demonstrating the robust nature of change blindness. All the children showed a strong change blindness effect and a clear difference between CI and MI trials

Disease Evolution and Response to Rapamycin in Activated Phosphoinositide 3-Kinase δ Syndrome: The European Society for Immunodeficiencies-Activated Phosphoinositide 3-Kinase δ Syndrome Registry

Activated phosphoinositide 3-kinase (PI3K) δ Syndrome (APDS), caused by autosomal dominant mutations in PIK3CD (APDS1) or PIK3R1 (APDS2), is a heterogeneous primary immunodeficiency. While initial cohort-descriptions summarized the spectrum of clinical and immunological manifestations, questions about long-term disease evolution and response to therapy remain. The prospective European Society for Immunodeficiencies (ESID)-APDS registry aims to characterize the disease course, identify outcome predictors, and evaluate treatment responses. So far, 77 patients have been recruited (51 APDS1, 26 APDS2). Analysis of disease evolution in the first 68 patients pinpoints the early occurrence of recurrent respiratory infections followed by chronic lymphoproliferation, gastrointestinal manifestations, and cytopenias. Although most manifestations occur by age 15, adult-onset and asymptomatic courses were documented. Bronchiectasis was observed in 24/40 APDS1 patients who received a CT-scan compared with 4/15 APDS2 patients. By age 20, half of the patients had received at least one immunosuppressant, but 2–3 lines of immunosuppressive therapy were not unusual before age 10. Response to rapamycin was rated by physician visual analog scale as good in 10, moderate in 9, and poor in 7. Lymphoproliferation showed the best response (8 complete, 11 partial, 6 no remission), while bowel inflammation (3 complete, 3 partial, 9 no remission) and cytopenia (3 complete, 2 partial, 9 no remission) responded less well. Hence, non-lymphoproliferative manifestations should be a key target for novel therapies. This report from the ESID-APDS registry provides comprehensive baseline documentation for a growing cohort that will be followed prospectively to establish prognostic factors and identify patients for treatment studies

The German National Registry of Primary Immunodeficiencies (2012-2017)

Introduction: The German PID-NET registry was founded in 2009, serving as the first national registry of patients with primary immunodeficiencies (PID) in Germany. It is part of the European Society for Immunodeficiencies (ESID) registry. The primary purpose of the registry is to gather data on the epidemiology, diagnostic delay, diagnosis, and treatment of PIDs. Methods: Clinical and laboratory data was collected from 2,453 patients from 36 German PID centres in an online registry. Data was analysed with the software Stata® and Excel. Results: The minimum prevalence of PID in Germany is 2.72 per 100,000 inhabitants. Among patients aged 1–25, there was a clear predominance of males. The median age of living patients ranged between 7 and 40 years, depending on the respective PID. Predominantly antibody disorders were the most prevalent group with 57% of all 2,453 PID patients (including 728 CVID patients). A gene defect was identified in 36% of patients. Familial cases were observed in 21% of patients. The age of onset for presenting symptoms ranged from birth to late adulthood (range 0–88 years). Presenting symptoms comprised infections (74%) and immune dysregulation (22%). Ninety-three patients were diagnosed without prior clinical symptoms. Regarding the general and clinical diagnostic delay, no PID had undergone a slight decrease within the last decade. However, both, SCID and hyper IgE- syndrome showed a substantial improvement in shortening the time between onset of symptoms and genetic diagnosis. Regarding treatment, 49% of all patients received immunoglobulin G (IgG) substitution (70%—subcutaneous; 29%—intravenous; 1%—unknown). Three-hundred patients underwent at least one hematopoietic stem cell transplantation (HSCT). Five patients had gene therapy. Conclusion: The German PID-NET registry is a precious tool for physicians, researchers, the pharmaceutical industry, politicians, and ultimately the patients, for whom the outcomes will eventually lead to a more timely diagnosis and better treatment

Diagnostica e modellistica della corona solare estesa

Dottorato di ricerca in astronomia. 11 ciclo. A.a. 1997 - 98. Coordinatore Giovanni Godoli e consigliere scientifico Giancarlo NociConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7 Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Il Fenomeno del Change Blindness: Fallimento del confronto o processo di sovrascrittura delle immagini?

Quando due immagini, uguali in tutto meno che in un particolare, si presentano sequenzialmente con un certo intervallo temporale (ISI), l’osservatore non riesece a rilevare il cambiamento. Tale fenomeno è noto come Change Blindness (CB). Mitroff et al (2004), utilizzando immagini di 1 sec e un ISI di 350ms, hanno evidenziato che i soggetti ricordano i dettagli di entrambe le immagini in percentuali maggiori della probabilità associata al ricordo di almeno una delle due e concludono riconducendo il CB al fallimento del confronto tra le due rappresentazioni visive. Questo studio ripropone lo studio di Mitroff, ipotizzando che stimoli e ISI di diverse durate temporali possano evidenziare situazioni in cui il fallimento del confronto non sia responsabile del CB. Metodo Hanno partecipato 31 studenti dell’University of Illinois. Veniva presentata per 240 o 2000 ms una griglia circolare con 9 oggetti seguita, dopo un ISI di 120 o 2000 ms, da un’altra griglia identica o con un oggetto diverso rispetto alla prima (paradigma flicker one-shot). Il compito richiedeva di indicare per 2 volte, in ordine random, quale oggetto era presente tra i 9 contenuti nella prima o nella seconda griglia. Risultati Una ANOVA Ricordo immagini (Entrambe, Una)x ISI x Durata stimolo sull’accuratezza ha evidenziato che la percentuale di ricordo dei dettagli di entrambi gli stimoli visivi non è diversa dalla probabilità di ricordare almeno uno dei due, solo quando la durata dello stimolo visivo è di 2000 ms (p< .00001). Conclusioni Il fallimento del confronto è responsabile del CB soltanto quando gli stimoli hanno una durata di 2 sec. Se la presentazione degli stimoli è breve (240 ms), la traccia mnestica è più labile e la percentuale di ricordo corretto per entrambi gli stimoli visivi è minore rispetto alla probabilità associata al ricordo di almeno uno stimolo. In questo caso è presumibile che il meccanismo responsabile del CB sia la sovrascritttura del secondo stimolo sul primo

Hemispheric transfer in alexithymic subjects

The emotion-feeling dissociation, which characterizes alexithymic subjects, has been ascribed to an impairment in callosal transfer of information. However, the results are not always unambiguous and they are often found using low sensitive interhemispheric transfer measures. We proposed to evaluate this hypothesis using a Poffemberger paradigm on half alexithymic and half nonalexithymic subjects. Results showed shorter RT in the uncrossed as respect to crossed conditions and an impairment, specific for the transfer from the right hemisphere to the left, only in the non alexithymic subjects, suggesting a specific disadvantage for the emotional hemisphere