Early Electrophysiological Markers of Navigational Affordances in Scenes

Scene perception and spatial navigation are interdependent cognitive functions, and there is increasing evidence that cortical areas that process perceptual scene properties also carry information about the potential for navigation in the environment (navigational affordances). However, the temporal stages by which visual information is transformed into navigationally relevant information are not yet known. We hypothesized that navigational affordances are encoded during perceptual processing and therefore should modulate early visually evoked ERPs, especially the scene-selective P2 component. To test this idea, we recorded ERPs from participants while they passively viewed computer-generated room scenes matched in visual complexity. By simply changing the number of doors (no doors, 1 door, 2 doors, 3 doors), we were able to systematically vary the number of pathways that afford movement in the local environment, while keeping the overall size and shape of the environment constant. We found that rooms with no doors evoked a higher P2 response than rooms with three doors, consistent with prior research reporting higher P2 amplitude to closed relative to open scenes. Moreover, we found P2 amplitude scaled linearly with the number of doors in the scenes. Navigability effects on the ERP waveform were also observed in a multivariate analysis, which showed significant decoding of the number of doors and their location at earlier time windows. Together, our results suggest that navigational affordances are represented in the early stages of scene perception. This complements research showing that the occipital place area automatically encodes the structure of navigable space and strengthens the link between scene perception and navigation.

A Measurement of Visual Complexity for Heterogeneity in the Built Environment Based on Fractal Dimension and Its Application in Two Gardens

In this study, a fractal dimension-based method has been developed to compute the visual complexity of the heterogeneity in the built environment. The built environment is a very complex combination, structurally consisting of both natural and artificial elements. Its fractal dimension computation is often disturbed by the homogenous visual redundancy, which is textured but needs less attention to process, so that it leads to a pseudo-evaluation of visual complexity in the built environment. Based on human visual perception, the study developed a method: fractal dimension of heterogeneity in the built environment, which includes Potts segmentation and Canny edge detection as image preprocessing procedure and fractal dimension as computation procedure. This proposed method effectively extracts perceptually meaningful edge structures in the visual image and computes its visual complexity which is consistent with human visual characteristics. In addition, an evaluation system combining the proposed method and the traditional method has been established to classify and assess the visual complexity of the scenario more comprehensively. Two different gardens had been computed and analyzed to demonstrate that the proposed method and the evaluation system provide a robust and accurate way to measure the visual complexity in the built environment.

Development and validation of a novel corpus of 269 verb pictures in Kannada based on an argument structure taxonomy

Pictorial stimuli are crucial in psycholinguistic research and clinical practice. The development of culturally and linguistically appropriate, standardized picture corpora is a tedious and meticulous process. Yet, such readily accessible picture sets are useful for researchers and clinicians alike. The current study introduces a novel set of 269 verb pictures for an Indian language – Kannada. The included verbs were selected from a published database of 100,000 words along with their frequency scores in this language, and were subsequently categorized based on an argument structure taxonomy. Each picture is developed based on an exemplar sentence that depicts a scenario rather than a mere action. Norms are provided for verb name and argument agreement, image agreement, concept familiarity, and visual complexity, along with the orthographic frequency. Correlations between these measures are also described. The complete set of pictures are freely downloadable from https://osf.io/uk2af/?view_only=ecffbd92f48546a484c869b3f0b8ec94 for academic, research, and clinical usage in the future.

SUBJECTIVE EVALUATION OF VISUAL COMPLEXITY, CLARITY, AND PREFERENCE OF INDOOR ENVIRONMENTS

Visual comfort, task performance, and observers’ satisfaction is affected by the dynamic nature of visual perception and cognition. The perceived quality of the visual environment can be investigated in terms of visual complexity, visual clarity, and visual preference. This paper investigates the relationship between visual preference, visual clarity, visual complexity, colourfulness and the effect of spatial characteristics of images on the perceived quality of indoor environments. A visual experiment is conducted to assess the accuracy of image quality metrics in estimating the visual complexity, visual clarity, visual preference, and colourfulness of 50 images of indoor environments. Seven image quality assessment measures were used to estimate observers’ subjective evaluations. Results indicate that image colourfulness metric M correlates statistically significantly with visual preference and perception of colourfulness. Visual complexity correlated with five of the metrics. Future research will investigate wide range on images, including human-made and outdoor scenes.

Cluttering Reduction for Interactive Navigation and Visualization of Historical Images

Iconographic representations, such as historical photos of geographic spaces, are precious cultural heritage resources capable of describing a particular geographical area’s evolution over time. These photographic collections may vary in size, between hundreds and thousands of items. With the advent of the digital era, many of these documents have been digitized, spatialized, and are available online. Browsing through these digital image collections represents new challenges. This paper examines the topic of historical image exploration in a virtual environment enabling the co-visualization of historical photos into a contemporary 3D scene. We address the topic of user interaction considering the potential volume of the input data. Our methodology is based on design guidelines that rely on visual perception techniques to ease visual complexity and improve saliency on specific cues. The designs are additionally implemented following an image-based rendering approach and evaluated in a group of users. Overall, these propositions may be a notable addition to creating innovative ways to visualize and discover historical images in a virtual geographic environment.

TIARA 2.0: an interactive tool for annotating discourse structure and text improvement

Discourse structure annotation aims at analysing how discourse units (e.g. sentences or clauses) relate to each other and what roles they play in the overall discourse. Several annotation tools for discourse structure have been developed. However, they often only support specific annotation schemes, making their usage limited to new schemes. This article presents TIARA 2.0, an annotation tool for discourse structure and text improvement. Departing from our specific needs, we extend an existing tool to accommodate four levels of annotation: discourse structure, argumentative structure, sentence rearrangement and content alteration. The latter two are particularly unique compared to existing tools. TIARA is implemented on standard web technologies and can be easily customised. It deals with the visual complexity during the annotation process by systematically simplifying the layout and by offering interactive visualisation, including clutter-reducing features and dual-view display. TIARA’s text-view allows annotators to focus on the analysis of logical sequencing between sentences. The tree-view allows them to review their analysis in terms of the overall discourse structure. Apart from being an annotation tool, it is also designed to be useful for educational purposes in the teaching of argumentation; this gives it an edge over other existing tools.

Background complexity can mitigate poor camouflage

Avoiding detection through camouflage is often key to survival. However, an animal's appearance is not the only factor affecting conspicuousness: background complexity also alters detectability. This has been experimentally demonstrated for both artificially patterned backgrounds in the laboratory and natural backgrounds in the wild, but only for targets that already match the background well. Do habitats of high visual complexity provide concealment to even relatively poorly camouflaged animals? Using artificial prey which differed in their degrees of background matching to tree bark, we were able to determine their survival, under bird predation, with respect to the natural complexity of the background. The latter was quantified using low-level vision metrics of feature congestion (or ‘visual clutter’) adapted for bird vision. Higher background orientation clutter (edges with varying orientation) reduced the detectability of all but the poorest background-matching camouflaged treatments; higher background luminance clutter (varying achromatic lightness) reduced average mortality for all treatments. Our results suggest that poorer camouflage can be mitigated by more complex backgrounds, with implications for both camouflage evolution and habitat preferences.

Analysis of Posters for Informing the Population via Social Media during Covid-19: Ukrainian Network

Objective. This study aims to determine the extent to which psycholinguistic variables are included in the analysis of the quality of directive posters on social media during Covid-19. Methods. The methods used in the study include analysis of the relevant scientific literature on the identification of psycholinguistic categories and variables relevant to the study; expert assessment of qualitative parameters of posters published on Facebook by official organizations; methods of descriptive statistics. Results. The analysis of 298 unique works conducted through Ukrainian network on Facebook revealed that the overall average quality of the publications is on the borderline between medium and high levels – 69.3% (by text parameters – 70.0%, graphic parameters – 68.6%). Conclusions. The study revealed that psycholinguistic variables such as readability, imageability, concreteness, conceptual familiarity, semantic size, name agreement, image agreement, visual complexity, typicality, image variability, authenticity of texts, processing fluency, etc. penetrate deeply related research on the creolized texts in various forms and interpretations. The quality of the posters on Facebook made by the official institutions operating in the field of health care is at the borderline between medium and high levels. These indicators are most in need of improvement on text parameters such as “Emphasis” and “Call to action”, as well as on graphical parameters such as “Presence of interactive graphic links” and “Understandability of illustration message without text”.