To what extent do Gestalt grouping principles influence tactile perception?

Since their formulation by the Gestalt movement more than a century ago, the principles of perceptual grouping have primarily been investigated in the visual modality and, to a lesser extent, in the auditory modality. The present review addresses the question of whether the same grouping principles also affect the perception of tactile stimuli. Although, to date, only a few studies have explicitly investigated the existence of Gestalt grouping principles in the tactile modality, we argue that many more studies have indirectly provided evidence relevant to this topic. Reviewing this body of research, we argue that similar principles to those reported previously in visual and auditory studies also govern the perceptual grouping of tactile stimuli. In particular, we highlight evidence showing that the principles of proximity, similarity, common fate, good continuation, and closure affect tactile perception in both unimodal and crossmodal settings. We also highlight that the grouping of tactile stimuli is often affected by visual and auditory information that happen to be presented simultaneously. Finally, we discuss the theoretical and applied benefits that might pertain to the further study of Gestalt principles operating in both unisensory and multisensory tactile perception.     

Cognitive Task Analysis for Implicit Knowledge About Visual Representations With Similarity Learning Methods

Visual representations are prevalent in STEM instruction. To benefit from visuals, students need representational competencies that enable them to see meaningful information. Most research has focused on explicit conceptual representational competencies, but implicit perceptual competencies might also allow students to efficiently see meaningful information in visuals. Most common methods to assess students’ representational competencies rely on verbal explanations or assume explicit attention. However, because perceptual competencies are implicit and not necessarily verbally accessible, these methods are ill‐equipped to assess them. We address these shortcomings with a method that draws on similarity learning, a machine learning technique that detects visual features that account for participants’ responses to triplet comparisons of visuals. In Experiment 1, 614 chemistry students judged the similarity of Lewis structures and in Experiment 2, 489 students judged the similarity of ball‐and‐stick models. Our results showed that our method can detect visual features that drive students’ perception and suggested that students’ conceptual knowledge about molecules informed perceptual competencies through top‐down processes. Furthermore, Experiment 2 tested whether we can improve the efficiency of the method with active sampling. Results showed that random sampling yielded higher accuracy than active sampling for small sample sizes. Together, the experiments provide the first method to assess students’ perceptual competencies implicitly, without requiring verbalization or assuming explicit visual attention. These findings have implications for the design of instructional interventions that help students acquire perceptual representational competencies.     

On the relationship between visual imagery and visual perception: Evidence from priming studies

Two priming experiments using a perceptual identification task were conducted to explore the functional and representational overlap between visual imagery and visual perception. The first experiment included a study phase in which primes were either perceived or imaged objects and a perceptual identification test task in which targets were parts of studied and non-studied objects. Imagery primed identification when subjects were instructed to count the parts of the imaged objects in the study phase but not when they were instructed to focus on the global shape of the imaged objects. This result suggests that imagery involves perceptual representations identical to those involved in perception. It also suggests that the representational overlap between imagery and perception depends on the type of images generated, as some images may consist in global shapes only, whereas others may consist in detailed, multi-part shapes. In the second experiment, we used whole objects as target stimuli which provided subjects with more information to identify masked targets and thereby reduced top-down processing. Priming from imagery fell beneath significance, suggesting that this sort of priming is elicited in a large part by a transfer of top-down processes from study to test.     

Toward ecologically realistic theories in visual short-term memory research

Recent evidence from neuroimaging and psychophysics suggests common neural and representational substrates for visual perception and visual short-term memory (VSTM). Visual perception is adapted to a rich set of statistical regularities present in the natural visual environment. Common neural and representational substrates for visual perception and VSTM suggest that VSTM is adapted to these same statistical regularities too. This article discusses how the study of VSTM can be extended to stimuli that are ecologically more realistic than those commonly used in standard VSTM experiments and what the implications of such an extension could be for our current view of VSTM. We advocate for the development of unified models of visual perception and VSTM—probabilistic and hierarchical in nature—incorporating prior knowledge of natural scene statistics.     

Visual Perception in Japanese Rock Garden Design

We present an investigation into the relation between design principles in Japanese gardens, and their associated perceptual effects. This leads to the realization that a set of design principles described in a Japanese gardening text by Shingen (1466), shows many parallels to the visual effects of perceptual grouping, studied by the Gestalt school of psychology. Guidelines for composition of rock clusters closely relate to perception of visual figure. Garden design elements are arranged into patterns that simplify figure-ground segmentation, while seemingly balancing the visual salience of subparts and the global arrangement. Visual ‘ground’ is analyzed via medial axis transformation (MAT), often associated with shape perception in humans. MAT analysis reveals implicit structure in the visual ground of a quintessential rock garden design. The MAT structure enables formal comparison of structure of figure and ground. They share some aesthetic qualities, with interesting differences. Both contain naturalistic asymmetric, self-similar, branching structures. While the branching pattern of the ground converges towards the viewer, that of the figure converges in the opposite direction.     

Working memory modulates the perception of time

Recent research has indicated that reentrant feedback from the contents of working memory can enhance neural representations and the perceptual strengths of matching stimuli in the visual field. However, whether the contents of working memory can also distort conscious experiences of perception remains unclear. Our present results show that the durations of perceptual stimuli matching the nontemporal representations in working memory tend to be perceived as longer than those of mismatching stimuli. This is the first demonstration that working memory can lead to distortions of time perception. Our findings are consistent with the ideas that the perceived duration of a stimulus depends on the magnitude of the neural responses to that stimulus in visual cortex and that there is a common system for representing both temporal and nontemporal magnitudes. We conclude that top-down modulation from the nontemporal contents of working memory distorts the perceptual experience of temporal duration.     

Learning to perceive object unity: a connectionist account

To explore questions of how human infants begin to perceive partly occluded objects, we devised two connectionist models of perceptual development. The models were endowed with an existing ability to detect several kinds of visual information that have been found important in infants’ and adults’ perception of object unity (motion, co‐motion, common motion, relatability, parallelism, texture and T‐junctions). They were then presented with stimuli consisting of either one or two objects and an occluding screen. The models’ task was to determine whether the object or objects were joined when such a percept was ambiguous, after specified amounts of training with events in which a subset of possible visual information was provided. The model that was trained in an enriched environment achieved superior levels of performance and was able to generalize veridical percepts to a wide range of novel stimuli. Implications for perceptual development in humans, current theories of development and origins of knowledge are discussed.     

Gestalt Psychology as a Missing Link in Ernst Cassirer’s Mythical Symbolic Form

The main goal of this article is to investigate the mythical symbolic form in Cassirer’s Philosophy of Symbolic Form regarding its connection with visual perception. The article argues that mythical symbolic form is rooted in Gestalt principles of perception for organizing the perceptual field, and shows that these principles shape the main features of space and time in Cassirer’s mythical symbolic form. This argument challenges Heidegger’s critique of Cassirer’s definition of a mythical symbolic form that it is directionless and not grounded in man’s being. The combination of Gestalt principles and mythical symbolic forms supports the argument about the active role of visual perception, and clarifies Cassirer’s application and re-definition of Kantian and Neo-Kantian concepts. The investigation opens a perspective for comprehending the mythic-religious phenomenon as well as for comprehending visual perception.     

The planning and control model (PCM) of motorvisual priming: reconciling motorvisual impairment and facilitation effects

Previous research on dual-tasks has shown that, under some circumstances, actions impair the perception of action-consistent stimuli, whereas, under other conditions, actions facilitate the perception of action-consistent stimuli. We propose a new model to reconcile these contrasting findings. The planning and control model (PCM) of motorvisual priming proposes that action planning binds categorical representations of action features so that their availability for perceptual processing is inhibited. Thus, the perception of categorically action-consistent stimuli is impaired during action planning. Movement control processes, on the other hand, integrate multi-sensory spatial information about the movement and, therefore, facilitate perceptual processing of spatially movement-consistent stimuli. We show that the PCM is consistent with a wider range of empirical data than previous models on motorvisual priming. Furthermore, the model yields previously untested empirical predictions. We also discuss how the PCM relates to motorvisual research paradigms other than dual-tasks.     

Experience,action and representations: Critical realism and the enactive theory of vision

This paper defends a dynamic model of the way in which perception is integrated with action, a model I refer to as ‘the navigational account’. According to this account, employing vision and other forms of distance perception, a creature acquires information about its surroundings via the senses, information that enables it to select and navigate routes through its environment, so as to attain objects that satisfy its needs. This form of perceptually guided activity should be distinguished from other kinds of semi-automatic responses to visual stimuli that do not necessarily involve conscious experiences. It essentially involves inner states, which involve both the awareness of phenomenal qualities, and also a representational component. The navigational account is compared here with the enactive approach to perception, which opposes the view that perceptual experiences are inner states. This paper argues that a full account of perception raises a number of different questions. One central explanatory project concerns questions about the kinds of processes that currently enable a creature to identify and respond appropriately to distant objects: the answer, it is argued, lies in acknowledging the role of conscious inner representations in guiding navigational behaviour through complex environments. The fact that perception and action are interdependent does not conflict with the claim that inner representational states comprise an essential stage in visual processing.

The integration of temporally shifted visual feedback in a synchronization task: The role of perceptual stability in a visuo-proprioceptive conflict situation

The present study examined whether the beneficial role of coherently grouped visual motion structures for performing complex (interlimb) coordination patterns can be generalized to synchronization behavior in a visuo-proprioceptive conflict situation. To achieve this goal, 17 participants had to synchronize a self-moved circle, representing the arm movement, with a visual target signal corresponding to five temporally shifted visual feedback conditions (0%, 25%, 50%, 75%, and 100% of the target cycle duration) in three synchronization modes (in-phase, anti-phase, and intermediate). The results showed that the perception of a newly generated perceptual Gestalt between the visual feedback of the arm and the target signal facilitated the synchronization performance in the preferred in-phase synchronization mode in contrast to the less stable anti-phase and intermediate mode. Our findings suggest that the complexity of the synchronization mode defines to what extent the visual and/or proprioceptive information source affects the synchronization performance in the present unimanual synchronization task.     

Temporal binding, binocular rivalry, and consciousness.

Cognitive functions like perception, memory, language, or consciousness are based on highly parallel and distributed information processing by the brain. One of the major unresolved questions is how information can be integrated and how coherent representational states can be established in the distributed neuronal systems subserving these functions. It has been suggested that this so-called "binding problem" may be solved in the temporal domain. The hypothesis is that synchronization of neuronal discharges can serve for the integration of distributed neurons into cell assemblies and that this process may underlie the selection of perceptually and behaviorally relevant information. As we intend to show here, this temporal binding hypothesis has implications for the search of the neural correlate of consciousness. We review experimental results, mainly obtained in the visual system, which support the notion of temporal binding. In particular, we discuss recent experiments on the neural mechanisms of binocular rivalry which suggest that appropriate synchronization among cortical neurons may be one of the necessary conditions for the buildup of perceptual states and awareness of sensory stimuli.     

知觉整体优先性的研究及其进展

知觉的性质是整体的还是分析的 ?这是心理学家们长期争论不休的问题。本世纪 70年代以来 ,一些认知心理学家提出知觉加工的整体优先性假设 ,强调整体在知觉加工中的优先地位。这一假设激发了大量整体 /局部范例的研究。本文综述了这方面的研究 ,分析了它们的理论假设 ,指出了这方面研究的局限以及替代的探讨。     

视觉短时记忆与视知觉的信息整合

与知觉整合和跨眼跳的信息整合一样,视觉短时记忆与视知觉的信息整合也是人们加工并保持整体性场景知觉的重要前提条件。近年来研究者们使用空白单元格定位任务进行了一些研究,试图寻求视觉短时记忆与视知觉信息整合的实验证据并探讨其整合机制。该文对已有的相关实验范式、实验证据和整合机制进行了介绍并加以分析,并指出未来研究可以在行为数据的基础上结合眼动和脑成像的数据寻求汇聚性证据     

Seeing what is not seen

This paper connects ideas from twentieth century Gestalt psychology, experiments in vision science, and Maurice Merleau-Ponty’s phenomenology of perception. I propose that when we engage in simple sensorimotor tasks whose successful completion is open, our behavior may be motivated by practical perceptual awareness alone, responding to invariant features of the perceptual field that are invisible to other forms of perceptual awareness. On this view, we see more than we think we see, as evidenced by our skillful bodily behavior.     

Neural correlates of object indeterminacy in art compositions

Indeterminate art invokes a perceptual dilemma in which apparently detailed and vivid images resist identification. We used event-related fMRI to study visual perception of representational, indeterminate and abstract paintings. We hypothesized increased activation along a gradient of posterior-to-anterior ventral visual areas with increased object resolution, and postulated that object resolution would be associated with visual imagery. Behaviorally, subjects were faster to recognize familiar objects in representational than in both indeterminate and abstract paintings. We found activation within a distributed cortical network that includes visual, parietal, limbic and prefrontal regions. Representational paintings, which depict scenes cluttered with familiar objects, evoked stronger activation than indeterminate and abstract paintings in higher-tier visual areas. Perception of scrambled paintings was associated with imagery-related activation in the precuneus and prefrontal cortex. Finally, representational paintings evoked stronger activation than indeterminate paintings in the temporoparietal junction. Our results suggest that perception of familiar content in art works is mediated by object recognition, memory recall and mental imagery, cognitive processes that evoke activation within a distributed cortical network.     

Extending the ALCOVE model of category learning to featural stimulus domains

The ALCOVE model of category learning, despite its considerable success in accounting for human performance across a wide range of empirical tasks, is limited by its reliance on spatial stimulus representations. Some stimulus domains are better suited to featural representation, characterizing stimuli in terms of the presence or absence of discrete features, rather than as points in a multidimensional space. We report on empirical data measuring human categorization performance across a featural stimulus domain and show that ALCOVE is unable to capture fundamental qualitative aspects of this performance. In response, a featural version of the ALCOVE model is developed, replacing the spatial stimulus representations that are usually generated by multidimensional scaling with featural representations generated by additive clustering. We demonstrate that this featural version of ALCOVE is able to capture human performance where the spatial model failed, explaining the difference in terms of the contrasting representational assumptions made by the two approaches. Finally, we discuss ways in which the ALCOVE categorization model might be extended further to use “hybrid” representational structures combining spatial and featural components.     

Motor Intentionality and its Primordiality

Is intentionality possible without representation? This paper considers the conditions under which intentionality without representation could occur and what sort of perceptual content such intentionality would have. In addition, it considers the constraints on non‐representational intentional content in organisms that have representation. The paper is divided into three parts. The first section compares and contrasts two opposed positions on non‐representational intentionality, those of Herbert Dreyfus and John Searle. The second section reviews a neurobiological model that accommodates the possibility of non‐representational perceptual content. The final section provides a puzzle for theories of non‐representational perceptual content, specifically in connection with the perception of representations. The puzzle of representation and perception illustrates a further need for all theories of perception, both philosophical and scientific: to provide a more finely developed definition of the notion of representation.