Perceptual Organization: An Overview

Perceptual organization concerns the organization of people’s perception into meaningful, structured entities—often wholes containing parts, with specific interrelationships among the parts as well as specific relationships between the parts and the wholes. It embraces a wide variety of distinct processes, which often occur together in everyday life and lead to interesting perceptual experiences by their interactions. The best-known perceptual organization processes are perceptual grouping and figure-ground organization, which appear to be determined by characteristic principles or laws, such as grouping by proximity, similarity, good continuation, area, convexity, symmetry, and so forth. Other important phenomena of perceptual organization include perceptual multi-stability (i.e., the fact that the same stimulus can give rise to multiple competing percepts that switch over time), visual illusions, the role of reference frames, and the role of context. Gestalt psychology has contributed deep insights into the way people’s perception of the world is organized, although it has also been criticized for its emphasis on subjective experiences and its sometimes vague and non-quantitative descriptions of the Gestalt principles. Because perceptual organization essentially concerns visual awareness, however, phenomenology is needed to describe what is experienced. This ultimately remains the basis for research on perceptual organization even when it is aimed at quantifying the principles of perceptual organization and identifying the neural correlates or mechanisms underlying perceptual organization.

Perceptual organization remains one of the very few established theories on the human visual system. It underpinned many pre-deep seminal works on segmentation and detection, yet research has seen a rapid decline since the preferential shift to learning deep models. Of the limited attempts, most aimed at interpreting complex visual scenes using perceptual organizational rules. This has however been proven to be sub-optimal, since models were unable to effectively capture the visual complexity in real-world imagery. In this paper, we rejuvenate the study of perceptual organization, by advocating two positional changes: (i) we examine purposefully generated synthetic data, instead of complex real imagery, and (ii) we ask machines to synthesize novel perceptually-valid patterns, instead of explaining existing data. Our overall answer lies with the introduction of a novel visual challenge – the challenge of perceptual question answering (PQA). Upon observing example perceptual question-answer pairs, the goal for PQA is to solve similar questions by generating answers entirely from scratch (see Figure 1). Our first contribution is therefore the first dataset of perceptual question-answer pairs, each generated specifically for a particular Gestalt principle. We then borrow insights from human psychology to design an agent that casts perceptual organization as a self-attention problem, where a proposed grid-to-grid mapping network directly generates answer patterns from scratch. Experiments show our agent to outperform a selection of naive and strong baselines. A human study however indicates that ours uses astronomically more data to learn when compared to an average human, necessitating future research (with or without our dataset).

How do we perceptually and cognitively organize incoming stimulation? A century ago, Gestalt psychologists posited the law of Prägnanz: psychological organization will always be as 'good' as possible given the prevailing conditions. To make the Prägnanz law a useful statement, it needs to be specified further (a) what a 'good' psychological organization entails, (b) how the Prägnanz tendency can be realized, and (c) which conditions need to be taken into account. Although the Gestalt school did provide answers to these questions, modern-day mentions of Prägnanz or good Gestalt often lack these clarifications. The concept of Prägnanz has been (mis)understood in many different ways, and by looking back on the rich history of the concept, we will attempt to present a more fine-grained view and promote a renewed understanding of the central role of Prägnanz in visual perception and beyond. We review Gestalt psychology's answers to the questions listed above, and also discuss the four main uses of the Prägnanz concept in more detail: (a) a Prägnanz tendency in each organizational process, (b) Prägnanz as a property of a Gestalt, (c) Prägnanz steps as internal reference points, and (d) Prägnanz in relation to aesthetic appreciation. As a key takeaway, Prägnanz is a multifaceted Gestalt psychological concept indicating the "goodness" of an experienced organization. Both the removal of unnecessary details and the emphasis on characteristic features of the overall organization compared to a reference organization can contribute to the emergence of a 'better' Gestalt. The stimulus constellation is not the only factor in determining the goodness of an organization, also the stimulus' interaction with an individual in a specific spatial and temporal context plays a role. Taking the ideas on Prägnanz as a generative framework and keeping the original Gestalt psychological context in mind, future research on perceptual organization can improve our understanding of the principles underlying psychological organization by further specifying how different organizational principles interact in concrete situations. Public significance statement: This paper reviews what a 'good' psychological organization entails, and how the incoming stimulation is clarified in human perception to achieve the best possible psychological organization. The review debunks common misconceptions on the meaning of "goodness" and synthesizes the most important perspectives and developments on "goodness" from its conception until now.

Functional organization of social perception networks in the human brain

Point clouds with ever-increasing volume are regular data in 3D city modelling, in which building reconstruction is a significant part. The photogrammetric point cloud, generated from UAS (Unmanned Aerial System) imagery, is a novel type of data in building reconstruction. Its positive characteristics, alongside its challenging qualities, provoke discussions on this theme of research. In this paper, patch-wise detection of the points of window frames on facades and roofs are undertaken using this kind of data. A density-based multi-scale filter is devised in the feature space of normal vectors to globally handle the matter of high volume of data and to detect edges. Color information is employed for the downsized data to remove the inner clutter of the building. Perceptual organization directs the approach via grouping and the Gestalt principles, to segment the filtered point cloud and to later detect window patches. The evaluation of the approach displays a completeness of 95% and 92%, respectively, as well as a correctness of 95% and 96%, respectively, for the detection of rectangular and partially curved window frames in two big heterogeneous cluttered datasets. Moreover, most intrusions and protrusions cannot mislead the window detection approach. Several doors with glass parts and a number of parallel parts of the scaffolding are mistaken as windows when using the large-scale object detection approach due to their similar patterns with window frames. Sensitivity analysis of the input parameters demonstrates that the filter functionality depends on the radius of density calculation in the feature space. Furthermore, successfully employing the Gestalt principles in the detection of window frames is influenced by the width determination of window partitioning.

A three-dimensional auditory display could take advantage of intrinsic sensory abilities like localization and perceptual organization by generating dynamic, multidimensional patterns of acoustic events that convey meaning about objects in the spatial world. Applications involve any context in which the user's situational awareness is critical, particularly when visual cues are limited or absent; e.g., air traffic control or telerobotic activities in hazardous environments. Such a display would generate localized cues in a flexible and dynamic manner. Whereas this can be readily achieved with an array of real sound sources or loudspeakers, the NASA-Ames prototype maximizes flexibility and portability by synthetically generating three-dimensional sound in realtime for delivery through headphones. Psychoacoustic research suggests that perceptually-veridical localization over headphones is possible if both the direction-dependent pinna cues and the more well understood cues of interaural time and intensity are adequately synthesized. Although the realtime device is not yet complete, recent studies at the University of Wisconsin have confirmed the perceptual adequacy of the basic approach to synthesis.

ABSTRACTBody movements like walking can synchronize with auditory and visual inputs presented within a periodic frequency range, peaking around 2 Hz. Some evidence has shown that the spontaneous tempo of human locomotion is around 2 Hz. The EEG frequency‐tagging approach allows us to capture the coupling of beat perception with neural brain oscillations at beat frequency. This study used EEG frequency tagging to explore brain dynamics during the perception of walking‐related sensory information in the auditory (footstep sounds) and visual (point‐light figure) modalities. Sensory inputs were delivered at different rates (1, 2, and 3.6 Hz) in rhythmic or random sequences while recording EEG activity. The experiment included three conditions: (i) auditory, (ii) visual, and (iii) audiovisual, including data from 22 participants. Results showed a main effect of rhythmic sequences compared with random sequences across all frequencies in all three auditory, visual, or audiovisual conditions. Specifically, at 2 Hz, rhythmic sequences enhanced neural entrainment in the sensorimotor cortex for auditory and audiovisual conditions. This effect was absent in the visual condition alone. Notably, 2 Hz rhythmic sequences in the audiovisual condition led to coupling with temporal, sensorimotor, and occipital regions. The study suggests that sensory auditory input related to walking movement presented at 2 Hz can mediate neural entrainment with sensorimotor areas. The findings of this study can have an impact on the spontaneous rhythmic integration of body movements using sensory inputs for walking rehabilitation.

[Perceptual Structures of Synthetic and Natural Vowels] The investigation which is reported here, forms part of a study which concentrates on the relation between acoustical dimensions of speech sounds on the one hand and some response dimensions on the other hand. The research is aimed at gaining more insight into the perceptual organization of vowels. In order to attain different levels or aspects of the perceptual organization, various experiments were designed in which the task of the subjects, in relation to the same stimulus materials, was very different. This report deals with the experiments concerning similarity judgements on pairs of human vowels and pairs of synthetic vowels. The synthetic vowels are generated with a five-formant parallel hardware synthesizer. The results from previous experiments on the naturalness (Fig. 1) and the identification-value (Tab. 3) of both kinds of vowels suggest that the selected physical parameters (Tab. 1), measured on the human vowels, allow the generation of synthetic vowels which match the natural ones This heigthens the external validity of our results. A multidimensional analysis on the pooled similarity data resulted for both kinds of vowels in a predicted structure (Fig. 3) with two qualitative dimensions. The first dimension reflects the distinctive features acute vs. grave and in there a tense/lax distinction. The second dimension reflects the distinctive features plain vs. flat and in there the compact/ diffuse contrast. A multidimensional analysis which lakes into account inter-individual differences in perception resulted for both kinds of vowels in a six-dimensional structure (Fig 4). The first, qualitative, dimension reflected the subjective importance of low versus high frequency information plus the position on the frequency scale (multiple r of D1 with the acute/grave and the plain/flat indices = .934). The other dimensions were related to the bandwith of the formants (r of D2 with ∑log10Bi = .970), the central frequency of the second formant (r of D3 with log10CF2 = .959). the central frequency of the first formant (r of D4 with log10CF1 = .933), the duration of the vowels (r of D5 with time in msec = .894) and the loudness (r of D6 with loudness indices = .839).

Generative Systems of Analyzers

Research Article| January 01 2010 Pediatric Clinical Ethics Consultation: Organizational Issues AAP Grand Rounds (2010) 23 (1): 9. https://doi.org/10.1542/gr.23-1-9 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Pediatric Clinical Ethics Consultation: Organizational Issues. AAP Grand Rounds January 2010; 23 (1): 9. https://doi.org/10.1542/gr.23-1-9 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search nav search search input Search input auto suggest search filter All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: ethics, clinical, ethics Source: Opel DJ, Wilfond BS, Brownstein D, et al. Characterisation of organizational issues in paediatric clinical ethics consultation: a qualitative study. J Med Ethics. 2009; 35(8): 477– 482; doi: https://doi.org/10.1136/jme.2008.027896Google Scholar Investigators from the University of Washington School of Medicine sought to identify and characterize organizational issues related to the ethical concerns that prompted patient-based pediatric ethics consultations at Seattle Children’s Hospital between 1996 and 2006. The medical records of study patients were reviewed looking for organizational issues germane to the ethics consultation. Prior to reviewing the data, four categories of organizational issues were defined: management, organizational culture, transfer of knowledge, and protocols and processes. Within these broad groups a total of 18 sub-categories were defined. Consultation notes were coded by independent observers for the presence of one or more types of organizational issues, and agreement between reviewers was assessed. Directed content analysis was used to identify whether an organizational issue related to the development of adverse clinical events and extended to ethics concerns. Among 71 consultations on patients aged 7 days to 21 years, most originated from the neonatal or pediatric intensive care units. One or more organizational issues were identified as contributing to the ethics issues in 96% of the consultations. The kappa statistic for agreement between reviewers regarding the presence of an organizational issue was >0.6, indicating greater than moderate agreement. The most frequent issues impacting the consultative process were: 1) organizational culture, where medical-ethical practices were guided by informal standards rather than defined policy – ie, an absence of a policy; 2) policy and procedure problems, where a particular organizational policy was available but not followed; and 3) poor communication between staff. Understanding these issues may suggest ways to prevent recurrence of similar ethical concerns and improve patient-doctor satisfaction. The authors of the current study identify three major systemic issues that can lead to stress for the patient, family, and medical staff, moral distress of the staff, and poor utilization of resources. By establishing administrative accountability coupled with evaluation and reporting processes, these problems can be lessened. For the ethics consultative process to work most effectively within a health care facility, the administration must be supportive, approachable, and willing to engage in discussions regarding clinical bedside care. Whereas both organizational ethics and directed bedside ethics (clinical consultative process) are concerned with patient care and well-being, the organizational aspect views ethical issues from a different, distinctly broader perspective.1 Organizational ethics has to do with the values of the organization. Elements that are conducive to ethical behavior within the organization include: 1) a written code of ethics and standards; 2) ethics training for all members of the organization; 3) availability for advice on ethical situations; and 4) systems for confidential reporting. The values of an organization are in part manifest by its maintenance and use of resources, budgets, accountability, administration, and its approach to evaluation, training, and education. A good example is the gathering... You do not currently have access to this content.

One issue of continuing debate in language research concerns whether the brain holds separate representations for semantic information through the auditory vs visual modalities. Regardless of whether we hear, see or read meaningful information, our brains automatically activate both auditory and visual semantic associations to the sensory input. The prominent models for how the brain makes these cross-modality associations holds that semantic information conveyed through either sensory input modality is represented in a shared semantic system comprising the traditionally identified language areas in the brain. A few recent case reports as well as activation imaging studies, have challenged this notion by demonstrating category-specific organization within the semantic system in spatially discrete brain regions. Neither view posits a role for primary sensory cortices in semantic processing. We obtained positron emission tomographic (PET) images while subjects performed an auditory responsive naming task, an auditory analog to visual object naming. Subjects heard and responded to descriptions of concrete objects while blindfolded to prevent visual stimulation. Our results showed that, in addition to traditional language centers, auditory language input produced reciprocal activation in primary and secondary visual brain regions, just as if the language stimuli had entered in the visual modality. These findings provide evidence for a distributed semantic system in which sensory-specific semantic modules are mutually interactive, operating directly onto early sensory processing centers.

One of the central tenets of Gestalt psychology is that configurations of stimulus elements are perceptually organized to have the lowest possible structural complexity—what is often referred to as the ‘‘minimum principle.’’ Consider, for example, the image of a Necker cube presented in the left panel of Figure 31.1. It is important to keep in mind that the actual physical structure of this figure is a 2D configuration of lines, but that is not how it is perceived. It appears instead as a 3D cube, presumably because that structure is simpler than the alternative 2D interpretation.

This study introduces and examines the principle of accentuation as a novel mechanism in perceptual organization, analyzing its effects through the framework of Grossberg’s Adaptive Resonance Theory (ART). We demonstrate that localized accentuators, manifesting as minimal dissimilarities or discontinuities, can significantly modulate global perceptions, inducing illusions of geometric distortion, orientation shifts, and apparent motion. Through a series of phenomenological experiments, we establish that accentuation can supersede classical Gestalt principles, influencing figure-ground segregation, shape perception, and lexical processing. Our findings suggest that accentuation functions as an autonomous organizing principle, leveraging salience-driven attentional capture to generate perceptual effects. We then apply the ART model to elucidate these phenomena, focusing on its core constructs of complementary computing, boundary–surface interactions, and resonant states. Specifically, we show how accentuation-induced asymmetries in boundary signals within the boundary contour system (BCS) can propagate through laminar cortical circuits, biasing figure-ground assignments and shape representations. The interaction between these biased signals and top–down expectations, as modeled by ART’s resonance mechanisms, provides a neurally plausible account for the observed illusions. This integration of accentuation effects with ART offers novel insights into the neural substrates of visual perception and presents a unifying theoretical framework for a diverse array of perceptual phenomena, bridging low-level feature processing with high-level cognitive representations.

In 1923, Gelb and Granit, using a method of adjustment for a small red light, reported a lower threshold for the target when presented on a ground region than on an adjacent figural region. More recent work in perceptual organization has found precisely the opposite—a processing advantage seems to go to items presented on the figure, not the ground. Although Gelb and Granit continue to be cited for their finding, it has not previously been available as an English translation. Understanding their methodology and results is important for integrating early Gestalt theory with more recent investigations.

This chapter describes how taste, olfactory, visual, oral sensory, and other sensory inputs are combined in the brain. It examines how a representation of reward value is produced, and shows how cognition and selective attention influence this processing. Complementary neuronal recordings in primates, and functional neuroimaging in humans, show that the primary taste cortex in the anterior insula provides separate and combined representations of the taste, temperature, and texture of food in the mouth independently of hunger and thus of reward value and pleasantness. In humans it has been shown in neuroimaging studies using functional magnetic resonance imaging (fMRI) that taste activates an area of the anterior insula/frontal operculum, which is probably the primary taste cortex, and part of the orbitofrontal cortex, which is probably the secondary taste cortex.