106 research outputs found
Separate cortical stages in amodal completion revealed by functional magnetic resonance adaptation : research article
Background Objects in our environment are often partly occluded, yet we effortlessly perceive them as whole and complete. This phenomenon is called visual amodal completion. Psychophysical investigations suggest that the process of completion starts from a representation of the (visible) physical features of the stimulus and ends with a completed representation of the stimulus. The goal of our study was to investigate both stages of the completion process by localizing both brain regions involved in processing the physical features of the stimulus as well as brain regions representing the completed stimulus. Results Using fMRI adaptation we reveal clearly distinct regions in the visual cortex of humans involved in processing of amodal completion: early visual cortex - presumably V1 - processes the local contour information of the stimulus whereas regions in the inferior temporal cortex represent the completed shape. Furthermore, our data suggest that at the level of inferior temporal cortex information regarding the original local contour information is not preserved but replaced by the representation of the amodally completed percept. Conclusion These findings provide neuroimaging evidence for a multiple step theory of amodal completion and further insights into the neuronal correlates of visual perception
Using light meters to investigate the light-myopia association
With the increasing prevalence of myopia, evaluating its relationship with objective light exposure as a potential adjustable environmental factor in myopia development has been an emerging research field in recent years. From a thorough literature search, we identify ten wearable light meters from human studies on light exposure and myopia and present an overview of their parameters, thereby demonstrating the wide between-device variability and discussing its implications. We further identify 20 publications, including two reanalyses, reporting investigations of light-myopia associations with data from human subjects wearing light meters. We thoroughly review the publications with respect to general characteristics, aspects of data collection, participant population, as well as data analysis and interpretation, and also assess potential patterns regarding the absence or presence of light-myopia associations in their results. In doing so, we highlight areas in which more research is needed as well as several aspects that warrant consideration in the study of light exposure and myopia
Feature-Based Attention Affects Direction-Selective fMRI Adaptation in hMT+
Functional magnetic resonance adaptation has been successfully used to reveal direction-selective responses in the human motion complex (hMT+). Here, we aimed at further investigating direction-selective as well as position-selective responses of hMT+ by looking at how these responses are affected by feature-based attention. We varied motion direction and position of 2 consecutive random-dot stimuli. Participants had to either attend to the direction or the position of the stimuli in separate runs. We show that direction selectivity in hMT+ as measured by functional magnetic resonance imaging (fMRI) adaptation was strongly influenced by task set. Attending to the motion direction of the stimuli lead to stronger direction-selective fMRI adaptation than attending to their position. Position selectivity, on the other hand, was largely unaffected by attentional focus. Interestingly, the change in the direction-selective adaptation profile across tasks could not be explained by inheritance from earlier areas. The response pattern in the early retinotopic cortex was stable across conditions. In conclusion, our results provide further evidence for the flexible coding of direction information in hMT+ depending on task demand
Multiple Object Tracking in Autism Spectrum Disorders
Difficulties in visual attention are often implicated in autism spectrum disorders (ASD) but it remains unclear which aspects of attention are affected. Here, we used a multiple object tracking (MOT) task to quantitatively characterize dynamic attentional function in children with ASD aged 5–12. While the ASD group performed significantly worse overall, the group difference did not increase with increased object speed. This finding suggests that decreased MOT performance is not due to deficits in dynamic attention but instead to a diminished capacity to select and maintain attention on multiple targets. Further, MOT performance improved from 5 to 10 years in both typical and ASD groups with similar developmental trajectories. These results argue against a specific deficit in dynamic attention in ASD.Ellison Medical FoundationSimons Foundatio
Global/Local Processing in Autism: Not a Disability, but a Disinclination
It is widely suggested that ASD is characterized by atypical local/global processing, but the published findings are contradictory. In an effort to resolve this question, we tested a large group of children on both a free-choice task and an instructed task using hierarchical local–global stimuli. We find that although children with autism showed a reduced preference to report global properties of a stimulus when given a choice, their ability to process global properties when instructed to do so is unimpaired. These findings support prior claims that people with ASD show a disinclination, not a disability, in global processing, and highlight the broader question of whether other characteristics of autism may also reflect disinclinations rather than disabilities.Ellison Medical FoundationSimons Foundatio
Head motion during fMRI tasks is reduced in children and adults if participants take breaks
Head motion remains a challenging confound in functional magnetic resonance imaging (fMRI) studies of both children and adults. Most pediatric neuroimaging labs have developed experience-based, child-friendly standards concerning e.g. the maximum length of a session or the time between mock scanner training and actual scanning. However, it is unclear which factors of child-friendly neuroimaging approaches are effective in reducing head motion. Here, we investigate three main factors including (i) time lag of mock scanner training to the actual scan, (ii) prior scan time, and (iii) task engagement in a dataset of 77 children (aged 6-13) and 64 adults (aged 18-35) using a multilevel modeling approach. In children, distributing fMRI data acquisition across multiple same-day sessions reduces head motion. In adults, motion is reduced after inside-scanner breaks. Despite these positive effects of splitting up data acquisition, motion increases over the course of a study as well as over the course of a run in both children and adults. Our results suggest that splitting up fMRI data acquisition is an effective tool to reduce head motion in general. At the same time, different ways of splitting up data acquisition benefit children and adults
Bolsista do ensino de gerenciamento em enfermagem: relato de experiência
The text aims to reflect the experience of being a scholarship student in the discipline of nursing management in health services II, in the Undergraduate Program in Nursing at the University of Santa Cruz do Sul – UNISC. This discipline occurs in the seventh semester of the course, being held in a Basic Public Health Unit. Practice happens in groups of six to eight students and during the same period of time there are related themes which are developed in the classroom. This method helps professors and students, allowing them to observe and interact on the way of organizing and managing the Basic Health Unit, in order to be able to collaborate with the necessary improvements. We conclude that it contributes with the professional formation of the student scholarship and academic, guiding him/her to a more comprehensive look at management and decision making in developing health policyEl texto tiene como objetivo reflejar la experiencia de ser becario de enseñanza en la asignatura de gestión de enfermerÃa en servicios de salud II, del Curso de Graduación en EnfermerÃa de la Universidad de Santa Cruz do Sul – UNISC. Esa materia se dicta en el séptimo semestre, cuyo desarrollo tiene lugar en una Unidad Básica de Salud. La práctica se hace con grupos de seis a ocho estudiantes y de modo concomitante se trabajan los temas en aula. Esa modalidad auxilia a los docentes y académicos, les permite observar y aprender sobre la forma de organización y gerencia de la Unidad Básica de Salud, para asà poder colaborar con las mejoras necesarias. Se concluye que la experiencia contribuye a la formación profesional del becario y académico, pues le permite tener una mirada más detallada sobre la gerencia y las tomas de decisión en el desarrollo de la polÃtica de salud.O texto objetiva refletir a experiência de ser bolsista de ensino da disciplina de gerenciamento de enfermagem em serviços de saúde II, do Curso de Graduação em Enfermagem da Universidade de Santa Cruz do Sul – UNISC. Esta disciplina ocorre no sétimo semestre, sendo realizada em uma Unidade Básica de Saúde. A prática acontece em grupos de seis a oito alunos e concomitante a esta prática são desenvolvidas temáticas em sala de aula. Esta modalidade auxilia os docentes e acadêmicos, permitindo observar e interagir sobre a forma de organização e gerenciamento da Unidade Básica de Saúde, para assim poder colaborar com as melhorias necessárias. Conclui-se que a experiência contribui para formação profissional do bolsista e acadêmico, despertando-o para um olhar mais abrangente sobre o gerenciamento e as tomadas de decisão no desenvolvimento da polÃtica de saúde
A meta-analysis of the uncanny valley's independent and dependent variables
The uncanny valley (UV) effect is a negative affective reaction to human-looking artificial entities. It hinders comfortable, trust-based interactions with android robots and virtual characters. Despite extensive research, a consensus has not formed on its theoretical basis or methodologies. We conducted a meta-analysis to assess operationalizations of human likeness (independent variable) and the UV effect (dependent variable). Of 468 studies, 72 met the inclusion criteria. These studies employed 10 different stimulus creation techniques, 39 affect measures, and 14 indirect measures. Based on 247 effect sizes, a three-level meta-analysis model revealed the UV effect had a large effect size, Hedges’ g = 1.01 [0.80, 1.22]. A mixed-effects meta-regression model with creation technique as the moderator variable revealed face distortion produced the largest effect size, g = 1.46 [0.69, 2.24], followed by distinct entities, g = 1.20 [1.02, 1.38], realism render, g = 0.99 [0.62, 1.36], and morphing, g = 0.94 [0.64, 1.24]. Affective indices producing the largest effects were threatening, likable, aesthetics, familiarity, and eeriness, and indirect measures were dislike frequency, categorization reaction time, like frequency, avoidance, and viewing duration. This meta-analysis—the first on the UV effect—provides a methodological foundation and design principles for future research
A Meta-analysis of the Uncanny Valley's Independent and Dependent Variables
The uncanny valley (UV) effect is a negative affective reaction to human-looking artificial entities. It hinders comfortable, trust-based interactions with android robots and virtual characters. Despite extensive research, a consensus has not formed on its theoretical basis or methodologies. We conducted a meta-analysis to assess operationalizations of human likeness (independent variable) and the UV effect (dependent variable). Of 468 studies, 72 met the inclusion criteria. These studies employed 10 different stimulus creation techniques, 39 affect measures, and 14 indirect measures. Based on 247 effect sizes, a three-level meta-analysis model revealed the UV effect had a large effect size, Hedges’ g = 1.01 [0.80, 1.22]. A mixed-effects meta-regression model with creation technique as the moderator variable revealed face distortion produced the largest effect size, g = 1.46 [0.69, 2.24], followed by distinct entities, g = 1.20 [1.02, 1.38], realism render, g = 0.99 [0.62, 1.36], and morphing, g = 0.94 [0.64, 1.24]. Affective indices producing the largest effects were threatening, likable, aesthetics, familiarity, and eeriness, and indirect measures were dislike frequency, categorization reaction time, like frequency, avoidance, and viewing duration. This meta-analysis—the first on the UV effect—provides a methodological foundation and design principles for future research
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