259 research outputs found
Рубаї в українській поезії
Рецензія на монографію: Сьомочкіна Олена. Рубаї в українській поезії: від канонізованої строфи до поліжанру. Монографія. - ІС: КиМУ, 2005. - 252 с
Atypical Development of Attentional Control Associates with Later Adaptive Functioning, Autism and ADHD Traits
Funder: H2020 European Research Council; doi: http://dx.doi.org/10.13039/100010663Funder: Research Foundation FlandersFunder: Universiteit Gent; doi: http://dx.doi.org/10.13039/501100004385Funder: Marguerite-Marie DelacroixFunder: Autistica; doi: http://dx.doi.org/10.13039/100011706Funder: Riksbankens Jubileumsfond; doi: http://dx.doi.org/10.13039/501100004472; Grant(s): NHS14-1802:1Funder: K.F. Hein FondsFunder: Scott Family Junior Research FellowshipAbstract: Autism is frequently associated with difficulties with top-down attentional control, which impact on individuals’ mental health and quality of life. The developmental processes involved in these attentional difficulties are not well understood. Using a data-driven approach, 2 samples (N = 294 and 412) of infants at elevated and typical likelihood of autism were grouped according to profiles of parent report of attention at 10, 15 and 25 months. In contrast to the normative profile of increases in attentional control scores between infancy and toddlerhood, a minority (7–9%) showed plateauing attentional control scores between 10 and 25 months. Consistent with pre-registered hypotheses, plateaued growth of attentional control was associated with elevated autism and ADHD traits, and lower adaptive functioning at age 3 years
A consensus guide to capturing the ability to inhibit actions and impulsive behaviors in the stop-signal task.
Response inhibition is essential for navigating everyday life. Its derailment is considered integral to numerous neurological and psychiatric disorders, and more generally, to a wide range of behavioral and health problems. Response-inhibition efficiency furthermore correlates with treatment outcome in some of these conditions. The stop-signal task is an essential tool to determine how quickly response inhibition is implemented. Despite its apparent simplicity, there are many features (ranging from task design to data analysis) that vary across studies in ways that can easily compromise the validity of the obtained results. Our goal is to facilitate a more accurate use of the stop-signal task. To this end, we provide 12 easy-to-implement consensus recommendations and point out the problems that can arise when they are not followed. Furthermore, we provide user-friendly open-source resources intended to inform statistical-power considerations, facilitate the correct implementation of the task, and assist in proper data analysis
Perspective on Canaletto’s Paintings of Piazza San Marco in Venice
Perspective plays an important role in the creation and appreciation of depth on paper and canvas. Paintings of extant scenes are interesting objects for studying perspective, because such paintings provide insight into how painters apply different aspects of perspective in creating highly admired paintings. In this regard the paintings of the Piazza San Marco in Venice by Canaletto in the eigh- teenth century are of particular interest because of the Piazza’s extraordinary geometry, and the fact that Canaletto produced a number of paintings from similar but not identical viewing positions throughout his career. Canaletto is generally regarded as a great master of linear perspective. Analysis of nine paintings shows that Canaletto almost perfectly constructed perspective lines and vanishing points in his paintings. Accurate reconstruction is virtually impossible from observation alone be- cause of the irregular quadrilateral shape of the Piazza. Use of constructive tools is discussed. The geometry of Piazza San Marco is misjudged in three paintings, questioning their authenticity. Sizes of buildings and human figures deviate from the rules of linear perspective in many of the analysed paintings. Shadows are stereotypical in all and even impossible in two of the analysed paintings. The precise perspective lines and vanishing points in combination with the variety of sizes for buildings and human figures may provide insight in the employed production method and the perceptual experi- ence of a given scene
Picture perception explored by comparing multiple photographs of perspective scenes
A picture is a powerful and convenient medium for inducing the illusion that one perceives a three-dimensional scene. The relative invariance of picture perception across viewing positions has aroused the interest of visual scientists for decades. This study explores variables that may underlie the invariance. To that end, sizes and distances of objects were analysed in sets of photographs of perspective scenes taken from different camera positions. Focal lengths of the lens were chosen such that one of the objects was depicted equally large in the two equally sized photographs. Manipulation of viewing distance and picture size showed that perceived distance is fully determined by angular size. Based on angular size, perceived distances of a near and a far object in a photograph were computed as function of viewing distance and compared with distances of the real objects. For real objects, differences between distances are constant as a function of viewing distance, however, ratios between dis- tances change. The opposite is true for depicted objects: Ratios of distances are constant whereas differences between distances change. Constant ratios signal standstill in the real world. Constant ratios are proposed as the reason for invariance of picture perception over a range of viewing distances
Geometric Constraints of Visual Space
Perspective space has been introduced as a computational model of visual space. The model is based on geometric features of visual space. The model has proven to describe a range of phenomena related to the visual perception of distance and size. Until now, the model lacks a mathematical description that holds for complete 3D space. Starting from a previously derived equation for per- ceived distance in the viewing direction, the suitability of various functions is analyzed. Functions must fulfill the requirement that straight lines, oriented in whatever direction in physical space, transfer to straight lines in visual space. A second requirement is that parallel lines oriented in depth in physical space, converge to a finite vanishing point in visual space. A rational function for perceived distance, compatible with the perspective-space model of visual space, satisfies the requirements. The function is unique. Analysis of alternative functions shows there is little tolerance for deviations. Conservation of the straightness of lines constrains visual space to having a single geometry. Visual space is described by an analytical function having one free parameter, that is, the distance of the vanishing point
Similar effects of repetitive transcranial magnetic stimulation of MT+ and a dorsomedial extrastriate site including V3A on pattern detection and position discrimination of rotating and radial motion patterns
Our recent psychophysical experiments have identified differences in the spatial summation characteristics of pattern detection and position discrimination tasks performed with rotating, expanding, and contracting stimuli. Areas MT and MST are well established to be involved in processing these stimuli. fMRI results have shown retinotopic activation of area V3A depending on the location of the center of radial motion in vision. This suggests the possibility that V3A may be involved in position discrimination tasks with these motion patterns. Here we use repetitive transcranial magnetic stimulation (rTMS) over MT+ and a dorsomedial extrastriate region including V3A to try to distinguish between TMS effects on pattern detection and position discrimination tasks. If V3A were involved in position discrimination, we would expect to see effects on position discrimination tasks, but not pattern detection tasks, with rTMS over this dorsomedial extrastriate region. In fact, we could not dissociate TMS effects on the two tasks, suggesting that they are performed by the same extrastriate area, in MT+
In the Eye of the Storm : Connectivity studies on antisocial behavior and psychopathy
This thesis consists of three sections. Section 1 is a proof of principle in which the functional contributions and mechanisms of interhemispheric connectivity will be addressed. The first chapter of Part 1 (§2.1) will examine the relationship between interhemispheric connectivity and personality features as measured per NEO-PI-R. In §2.2, the influence of alcohol on interhemispheric connectivity will be examined. This is of particular importance as more than 50% of all violent crimes are associated with alcohol (93) and up to 86% of all murders (94). The last chapter of part 1 (§2.3) is a methodological intermezzo in which we will examine the functional mechanisms associated with ISP by relating it to a second TMS measure of interhemispheric connectivity, IHI. The second part is the core of this thesis and it consists of 3 chapters in which TMS, EEG and DTI will be used to evaluate the integrity of brain networks in psychopathic offenders. In §3.1 we will examine whether psychopaths suffer from interhemispheric connectivity deficits by measuring their ISP and comparing it to that of healthy controls. Also, cortical inhibition and facilitation will be measured in the left and right motor cortex. In §3.2, an essential component of brain networks, white matter, will be assessed in psychopaths through diffusion tensor imaging (DTI). Using a tract based spatial statistics (TBSS) approach we explore white matter integrity throughout the brain in psychopathic offenders and compare them to healthy controls. Based on what was described in the previous pages an amygdalo-prefrontal network might be affected in addition to the mesolimbic reward pathway. §3.3 will test for the first time whether psychopathic offenders have inhibitory abnormalities in the DLPFC as compared to non-psychopathic individuals. To this end, we will use TMS in combination with EEG and assess LICI in the motor cortex and DLPFC. In addition, we will index working memory performance as it has been previously shown that psychopathic offenders may have impairments in this cognitive function. Part 3 endeavours into possible contributors to antisocial behavior. Here, in §4.1, we present the cerebellum as a key brain structure that is affected in many neuropsychiatric disorders including schizophrenia and autism. We will consider evidence for potential cerebellar involvement in disinhibited behavior. In §4.2, a rTMS manipulation of the cerebellum will be introduced to see whether alterations of cerebellar activity induce affective changes. To measure affective changes we use an affective pictorial Stroop task
The price of learning good from bad: motivational costs and benefits in cognition and affect
The studies presented in this thesis addressed the interactions between motivation, emotion, and cognition. The starting point for the research in this thesis was the question how inter-individual neurophysiological differences can be related to reward- and threat-related learning processes. Central to this question was the idea that individual differences in resting-state electrophysiological activity reflect motivational reward and punishment drives, and would therefore be predictive for acquiring associations in n reinforcement learning and fear conditioning tasks. The first part of the thesis focused on resting-state EEG theta/beta ratio in relation to reinforcement learning, and on EEG orienting responses in fear conditioning. In the second section of this thesis the focus was shifted to the interaction between threat, reward and attention. I presented studies on how stimuli that are predictive of negative (aversive noise, monetary loss) and positive events (monetary gain) exert an influence on spatial attention. Furthermore, I have examined the contributions of trait anxiety on attentional control and motor inhibition. The third section was concerned with the influence of mental fatigue as a result of prolonged periods of cognitive performance on cognitive processing and motivational responses to reward and loss
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