Implicit identification of irrelevant local objects interacts with global/local processing of hierarchical stimuli

The Order & Complexity Toolbox for Aesthetics (OCTA): A systematic approach to study the relations between order, complexity, and aesthetic appreciation

Do individuals prefer stimuli that are ordered or disordered, simple or complex, or that strike the right balance of order and complexity? Earlier research mainly focused on the separate influence of order and complexity on aesthetic appreciation. When order and complexity were studied in combination, stimulus manipulations were often not parametrically controlled, only rather specific types of order (i.e., balance or symmetry) were usually studied, and/or the multidimensionality of order and complexity was largely ignored. Progress has also been limited by the lack of an easy way to create reproducible and expandible stimulus sets, including both order and complexity manipulations. The Order & Complexity Toolbox for Aesthetics (OCTA), a Python toolbox that is also available as a point-and-click Shiny application, aims to fill this gap. OCTA provides researchers with a free and easy way to create multi-element displays varying qualitatively (i.e., different types) and quantitatively (i.e., different levels) in order and complexity, based on regularity and variety along multiple element features (e.g., shape, size, color, orientation). The standard vector-based output is ideal for experiments on the web and the creation of dynamic interfaces and stimuli. OCTA will not only facilitate reproducible stimulus construction and experimental design in research on order, complexity, and aesthetics. In addition, OCTA can be a very useful tool in any type of research using visual stimuli, or even to create digital art. To illustrate OCTA's potential, we propose several possible applications and diverse questions that can be addressed using OCTA.

Neurobehavioral Phenotype and Dysexecutive Syndrome of Preterm Children: Comorbidity or Trigger? An Update

Premature birth is a worldwide public health priority. One in ten children is born before 37 weeks of gestational age and, in developed countries, survival rates without major neonatal morbidity are increasing. Although severe sequelae associated with these births have decreased, their neurobehavioral difficulties, often associated in multiple fields, remain stable but still widespread. These neurobehavioral difficulties hamper the normal development of academic achievements and societal integration and intensify the children's needs for rehabilitation during their preschool and academic years. Severe sequelae increase when gestational age decreases. This is even truer if the socio-cultural background is impeded by low income, education and language skills as compared with defined averages. However, moderate and/or minor neurocognitive and/or behavioral difficulties are almost identical for a moderate or a late preterm birth. Obtaining a better clinical description of neurobehavioral characteristics of those pretermly born, once they reach preschool age, is essential to detect behavioral issues as well as early specific cognitive difficulties (working memory, planning, inhibition, language expression and reception, attention and fine motor skills, etc.). Such information would provide a better understanding of the executive functions' role in brain connectivity, neurodevelopment and neuroanatomical correlation with premature encephalopathy.

Local vs global processing in Williams syndrome

BACKGROUND

It has long been debated whether in Williams syndrome (WS) there is a preferential processing of local with respect to global forms, in contrast to the typical 'global advantage' in healthy individuals, which in WS seems to exist only for faces.

AIMS

We aimed at verifying it and to assess the role of stimulus familiarity by comparing performances with faces to those with other objects using the same type of task.

METHODS AND PROCEDURE

A group of children and adolescents with WS and controls with typical development performed a modified version of three tasks: Mooney (with faces and/or guitars), Jane (with faces and houses) and Navon task.

OUTCOMES AND RESULTS

Individuals with WS were able to process at a global level not only faces but also objects, although they were impaired when they had to compare or discriminate between two stimuli. All groups showed an advantage for global processing, with familiarity improving it. However, WS participants did not benefit from familiarity as much as typically developing young individuals.

CONCLUSIONS AND IMPLICATIONS

Peculiar abilities for face stimuli in WS did not emerge nor did a clear facilitation related to object familiarity. These results are useful for planning effective interventions.

Responses to Navon tasks differ across development and between tasks with differing attentional demands

Navon hierarchical stimuli are designed to measure responses to the global level (grouped local elements, e.g. a forest) and the local level (individuated local elements, e.g. trees) of a visual scene. Cross-sectional evidence suggests that there are developmental changes in global and local processing. We examined global and local processing in 135 typically developing children in Year 1 (aged 5-6 year), Year 3 (aged 7-8 years), and Year 5 (aged 9-10 years). Participants completed a range of Navon tasks, each with different attentional demands. The design of the Navon stimuli remained constant across the tasks, ensuring that any task-related differences were not due to stimulus characteristics. Sixty children from Years 1 and 3 repeated the testing session two years later. Linear mixed model analyses combined longitudinal and cross-sectional data to assess developmental changes and the influence of attentional task demands on responses. The results revealed differing patterns of global and local processing responses according to Year group and attentional task demands. We found some evidence of developmental change in responses from a relatively more local advantage to a relatively more global advantage, which is consistent with the literature. However, the age at which this transition occurred varied across the tasks. We conclude that responses to hierarchical Navon stimuli are modulated by attentional task characteristics which mask any underlying global or local processing advantage.

Functional involvement of subcortical structures in global-local processing

The present study examined the involvement of subcortical structures in the processing of global and local information. To this end, we used a stereoscope to present hierarchical stimuli (global shapes composed of local elements) in a dichoptic or a monocular fashion, such that global and local information was either presented to the same eye (same-eye condition) or segregated between the eyes (different-eyes condition). In Experiment 1, the typical global advantage and global-to-local interference were observed for the same-eye presentation condition. On the other hand, no indication of a global advantage or of global-to-local interference emerged in the different-eyes presentation condition. In Experiment 2 we replicated these results, ruling out a possible alternative explanation that the pattern of results observed for the different-eyes presentation condition resulted merely from segregation of the stimulus between the eyes. Rather, the experiment demonstrated that the global-to-local interference was eliminated only when global and local information was segregated between the eyes. Taken together, these findings suggest that processing the global aspect of hierarchical stimuli involves subcortical regions indexed by monocular portions of the visual system.

Brief Report: Visual Perception, Task-Induced Pupil Response Trajectories and ASD Features in Children

We applied a trajectory-based analysis to eye tracking data in order to quantify individualized patterns of pupil response in the context of global-local processing that may be associated with autism spectrum disorder (ASD) features. Multiple pupil response trajectories across both global and local conditions were identified. Using the combined trajectory patterns for global and local conditions for each individual, we were able to identify three groups based on trajectory group membership that were thought to reflect perceptual strategy. Results indicated that the proportion of children with ASD was significantly greater in the group demonstrating a local-focus response. This research presents a novel analytic approach to the objective characterization of individualized pupil response patterns that are associated with ASD features.

Lost in the forest? Global to local interference depends on children's reading skills

We studied the global precedence effect in primary school children with and without developmental dyslexia, using a compound figures task with familiar (Latin) or unfamiliar (Hebrew) letters. The two components of the global precedence effect were considered separately: global advantage (faster processing of global than local letters) and asymmetric interference (global distracters interfere with local targets but not vice versa). Both groups of children showed a global advantage with familiar as well as with unfamiliar letters. Children without developmental dyslexia showed asymmetric interference on familiar letters, but not on unfamiliar ones. Children with developmental dyslexia showed no asymmetric interference, neither for familiar letters nor for unfamiliar ones. The results distinguish between alternative hypothesis regarding the roles of familiarity and visual processing strategies in the compound figures task. Consequences for understanding literacy acquisition and developmental dyslexia are discussed.

Long-range correlations and patterns of recurrence in children and adults' attention to hierarchical displays

In order to make sense of a scene, a person must pay attention to several levels of nested order, ranging from the most differentiated details of the display to the integrated whole. In adults, research shows that the processes of integration and differentiation have the signature of self-organization. Does the same hold for children? The current study addresses this question with children between 6 and 9 years of age, using two tasks that require attention to hierarchical displays. A group of adults were tested as well, for control purposes. To get at the question of self-organization, reaction times were submitted to a detrended fluctuation analysis and a recurrence quantification analysis. H exponents show a long-range correlations (1/f noise), and recurrence measures (percent determinism, maximum line, entropy, and trend), show a deterministic structure of variability being characteristic of self-organizing systems. Findings are discussed in terms of organism-environment coupling that gives rise to fluid attention to hierarchical displays.

Letters in the forest: global precedence effect disappears for letters but not for non-letters under reading-like conditions

Normally skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known global precedence effect (GPE) seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5° of visual angle) and local stimuli close to the critical size for fluent reading of individual letters (0.5° of visual angle). Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to-local interference). We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters.

Global precedence effect in audition and vision: evidence for similar cognitive styles across modalities

This study aimed to provide evidence for a Global Precedence Effect (GPE) in both vision and audition modalities. In order to parallel Navon's paradigm, a novel auditory task was designed in which hierarchical auditory stimuli were used to involve local and global processing. Participants were asked to process auditory and visual hierarchical patterns at the local or global level. In both modalities, a global-over-local advantage and a global interference on local processing were found. The other compelling result is a significant correlation between these effects across modalities. Evidence that the same participants exhibit similar processing style across modalities strongly supports the idea of a cognitive style to process information and common processing principle in perception.

What does the nature of the stimuli tell us about the Global Precedence Effect?

The "Global Precedence Effect" (GPE) is a well-established phenomenon characterised by a global advantage (global response times that are faster than local response times) and an interference effect from global distractors during identification of local targets but not vice versa. In the present study, two experiments were carried out to examine how the GPE is affected by the meaningfulness of the stimuli. Using global/local compound stimuli based on either meaningful or meaningless stimuli, we found, on the one hand, that the global level was always processed faster than the local level, irrespective of the meaningfulness of the material. On the other hand, results show that the interference effect occurred only with meaningful stimuli. We propose that automatic identification of meaningful stimuli plays a role in the interference effect. These results suggest that the GPE involves both "sensory mechanisms" (responsible for the global advantage) and "cognitive mechanisms" (responsible for the interference effect).

Seeing the Forest Before the Trees Depends on Individual Field-Dependency Characteristics

Numerous studies have demonstrated that the well-known global precedence effect, characterized by a visual bias toward global information, is highly dependent on stimulus characteristics ( Kimchi, 1992 ). Despite the extensive global-local literature, few studies have investigated how interindividual characteristics could affect the global precedence effect. In this framework, we studied the relationship between global-local visual biases and the Group Embedded Figure Test (GEFT), a standardized measure of field dependency. Data from 34 participants were consistent with the idea that an individual’s bias toward the global level is linearly related to his or her degree of field dependence. Given the important role that global-local visual skills play during visuospatial tasks, these results have important implications for future research in this area.