This paper argues that a theory of situated vision, suited for the dual purposes of object recognition and the control of action, will have to provide something more than a system that constructs a conceptual representation from visual stimuli: it will also need to provide a special kind of direct (preconceptual, unmediated) connection between elements of a visual representation and certain elements in the world. Like natural language demonstratives (such as `this' or `that') this direct connection allows entities (...) to be referred to without being categorized or conceptualized. Several reasons are given for why we need such a preconcep- tual mechanism which individuates and keeps track of several individual objects in the world. One is that early vision must pick out and compute the relation among several individual objects while ignoring their properties. Another is that incrementally computing and updating representations of a dynamic scene requires keeping track of token individuals despite changes in their properties or locations. It is then noted that a mechanism meeting these requirements has already been proposed in order to account for a number of disparate empiri- cal phenomena, including subitizing, search-subset selection and multiple object tracking (Pylyshyn et al., Canadian Journal of Experimental Psychology 48(2) (1994) 260). This mechanism, called a visual index or FINST, is brie. (shrink)

This paper describes a programmatic theory of a process in early vision called indexing. The theory hypothesizes that a small number of primitive indexes are available for individuating, tracking and providing direct access to salient visual objects. We discuss some empirical and theoretical arguments in favor of the proposed index as a resource-limited link between an internal visual representation and objects in the visual world. We argue that this link is needed to explain a large range (...) of properties of vision, including the ability to simultaneously track multiple moving objects, to select a subset of visual items to process, as well as such larger issues as how mental images get their apparent metrical properties and why the world appears stable despite constant retinal motion. (shrink)

The advent of digital cameras has provided photographers, with varying levels of expertise, the opportunity to accumulate large repositories of digital images. However, this expansion has also brought the attendant difficulty of image retrieval. This paper reviews the considerable work already carried out on image retrieval and identifies critical constraints in attempting to handle the underlying semantics of photographic images. The authors address the issue of how an amateur photographer, storing several thousand images a year, can effectively and efficiently manage (...) a personal collection. A number of surprisingly simple techniques are proposed utilising a sparse lexical ontology alongside iconic visual clues to identify key representative events in the collection. The photographer’s associated knowledge and experience, often shared by others who are attuned to the context of the collection, are critical to the effective management of the images. The authors recommend the use of existing browsers and a simple keyword table to facilitate concise and effective image storage and retrieval. Photographers can further enrich the representation of their collection by clustering images in accordance with their perceived relevance and aesthetic qualities. The authors argue that these properties can also be exploited to enhance retrieval. (shrink)

Research in vision science, developmental psychology, and the foundations of cognitive science has led some theorists to posit referential mechanisms similar to indices. This hypothesis has been framed within a Fodorian conception of the early vision module. The article shows that this conception is mistaken, for it cannot handle the ‘interface problem’—roughly, how indexing mechanisms relate to higher cognition and conceptual thought. As a result, I reject the inaccessibility of early vision to higher cognition and make some constructive remarks (...) on the perception–cognition interface. -/- 1 The Case for Visual Indices 1.1 Preliminary assumptions 1.2 Transcendental arguments 1.3 Evidence from vision science 2 Visual Indices, Object Files, and Fodorian Modularity 3 The Interface Problem 3.1 Top-down attention and modularity 3.2 Selective attention and information 4 Revising the Indexing Hypothesis 4.1 Revising the perception–cognition interface 4.2 Revising the modularity of early vision 5 Concluding Remarks. (shrink)

Based on increased user experience during stimulation, frequency-modulated steady-state visual evoked potentials have been suggested as an improved stimulation method for brain-computer interfaces. Adapting such a novel stimulation paradigm requires in-depth analyses of all different stimulation parameters and their influence on brain responses as well as the user experience during the stimulation. In the current manuscript, we assess the influence of different values for the modulation index, which determine the spectral distribution in the stimulation signal on FM-SSVEPs. We visually (...) stimulated 14 participants at different target frequencies with four different values for the modulation index. Our results reveal that changing the modulation index in a way that elevates the stimulation power in the targeted sideband leads to increased FM-SSVEP responses. There is, however, a tradeoff with user experience as increased modulation indices also lead to increased perceived flicker intensity as well as decreased stimulation comfort in our participants. Our results can guide the choice of parameters in future FM-SSVEP implementations. (shrink)

Attentional bias has been suggested to contribute to the persistence of substance use behavior. However, the empirical evidence for its proposed role in addiction is inconsistent. This might be due to the inability of commonly used measures to differentiate between attentional engagement and attentional disengagement. Attesting to the importance of differentiating between both components of AB, a recent study using the odd-one-out task showed that substance use was differentially related to engagement and disengagement bias. However, the AB measures derived from (...) the OOOT showed insufficient reliability to be used as a solid measure of individual differences. Therefore, the current study aimed to improve the reliability of the AB measures derived from the OOOT by using more distinct contrast stimuli, adding practice trials, increasing the number of trials, and by having participants perform the task in an alcohol-relevant context. We contrasted the original OOOT with the adapted OOOT and assessed AB in low- and high-drinking individuals. Participants were 245 undergraduate students who typically tend to drink either low or high amounts of alcohol. In one condition, AB was measured with the original OOOT in a typical laboratory context, whereas in the other condition, AB was measured with the OOOT-adapt in a bar context. The OOOT-adapt showed superior internal consistency, especially for the high-drinking group. Further, specifically the OOOT-adapt differentiated between low- and high-drinking participants showing that high drinkers engaged faster with alcohol cues than did low drinkers. Thus, the OOOT-adapt was found to be a promising candidate to reliably index AB in the context of alcohol use. The OOOT-adapt further showed superior criterion validity as it could differentiate between low- and high-drinking individuals, thereby adding to the evidence that AB might be involved in substance use behavior. (shrink)

Current cognitive models of addiction imply that speeded detection and increased distraction from substance cues might both independently contribute to the persistence of addictive behavior. Speeded detection might lower the threshold for experiencing craving, whereas increased distraction might further increase the probability of entering a bias-craving-bias cycle, thereby lowering the threshold for repeated substance use. This study was designed to examine whether indeed both attentional processes are involved in substance use disorders. Both attentional processes were indexed by an Odd-One-Out (...) class='Hi'>visual search task in individuals diagnosed with alcohol use disorder and cannabis use disorder. To test whether the detection and/or the distraction component are characteristic for AUD and CUD, their indices were compared with matched individuals without these diagnoses. Individuals with CUD showed speeded detection of cannabis cues; the difference in detection between AUD and the comparison group remained inconclusive. Neither the AUD nor the CUD group showed more distraction than the comparison groups. The sample size of the CUD group was relatively small. In addition, participants made relatively many errors in the attentional bias task, which might have lowered its sensitivity to detect ABs. The current study provided no support for the proposed role of increased distraction in CUD and AUD. The findings did, however, provide support for the view that speeded detection might be involved in CUD. Although a similar trend was evident for AUD, the evidence was weak and remained therefore inconclusive. (shrink)

In Multiple Object Tracking (MOT), an observer is able to track 4 – 5 objects in a group of otherwise indistinguishable objects that move independently and unpredictably about a display. According to the Visual Indexing Theory (Pylyshyn, 1989), successful tracking requires that target objects be indexed while they are distinct -- before tracking begins. In the typical MOT task, the target objects are briefly flashed resulting in the automatic assignment of indexes. The question arises whether indexes are only (...) assigned automatically or whether they can be assigned voluntarily in a top-down manner. This study compares several ways of specifying which of 8 items are the targets to be tracked. In the Flash condition the target items were flashed, in the Nonflash condition the targets were the items not flashed, and in the Number condition the targets were specified by number (e.g., items numbered 1-4). The results showed no difference between the three conditions, suggesting that tracking was possible with either voluntary or involuntary indexing. The second experiment tested the hypothesis that voluntary indexing is possible only if the target items are visited serially. The conditions were the same as experiment 1 except that the time available for index assignment was too short to allow targets to be visited serially. In this experiment, targets flashed only once (or, in the Numbers condition, remained visible for about 400 ms). The results showed a decrease in tracking performance for the Number condition, but the Flash and the Nonflash conditions did not differ, suggesting that as long as the designation of targets was done rapidly, the observer did not have to visit each target serially in order to index it. These results suggest that indexing can occur both automatically and voluntarily, and without serially visiting them, so long as the items are successfully specified. (shrink)

La conception naïve de l’expérience visuelle dépeint celle-ci comme une relation directe, primitive, entre le sujet voyant et l’objet vu. Elle repose sur une opposition entre la relation visuelle et la représentation mentale de l’objet vu dans l’imagination visuelle ou la vision des images. Le but de cet article est de suggérer que l’opposition naïve entre relation et représentation présente un intérêt philosophique et scientifique parfois sous-estimé. Deux théories philosophiques de la perception sont présentées : le relationnisme reprend l’esprit de (...) la conception naïve en analysant l’expérience visuelle comme une relation non représentationnelle à l’objet vu, alors que l’intentionnalisme rejette la conception naïve comme inadéquate et considère que l’expérience visuelle est représentationnelle de part en part. Après avoir introduit une notion générale de « représentation » acceptable par les deux parties, nous examinons un ensemble de travaux issus des sciences cognitives et susceptibles d’arbitrer le débat entre relationnisme et intentionnalisme. La thèse principale défendue est que le relationnisme est compatible avec les données scientifiques à notre disposition sur les processus cognitifs liés à la vision. Le relationnisme présente également un avantage philosophique puisqu’il permet de comprendre comment les représentations mentales, y compris visuelles, peuvent être fondées sur un rapport cognitif plus direct, c’est-à-dire intrinsèquement relationnel, au monde visible. (shrink)

Charles S. Peirce’s second trichotomy, which introduces the concepts of iconicity, indexicality, and symbolicity, is probably the only piece of his semiotic that is familiar to visual artists and designers. Although the concepts have found their way into the academy, their utility in the field has been reduced for a couple of reasons. First, as with all of Peirce’s philosophy, his second trichotomy is a concept that is subtle, fluid, and difficult to fully grasp in a sound bite. Second, (...) there has simply been no bridge concept that would form a working connection between that philosophy in its logical guise and the studio practice in the visual arts. The purpose of this article is to remedy that situation by investigating the subtle ways the second trichotomy functions within the visual sphere, and to then suggest a model that can serve to bridge the divide between pure theory and practice. The article makes four main points: first, using examples from visual identity and the graphic arts, it demonstrates how the modes of icon, index, and symbol tend to be blended; second, examples from fine art are used to illustrate how the concept of abstraction, as used in the art world, can only be partially accounted for within the second trichotomy, but can be modeled by supplying a syntactical supplement; third, it expands on and elaborates a previously sketched model, the visual gamut, which makes it possible to classify visual entities according to their position within a map of semantic and syntactic space; finally, it concludes by suggesting ways this enhanced version of the visual gamut model might be used in the analysis of, or creation of, art and design, presenting suggestions for further study. (shrink)

This study aimed to explore the influence of the visuospatial active working memory sub-components on early math skills in young children, followed longitudinally along the first two years of primary school. We administered tests investigating visual active working memory (jigsaw puzzle), spatial active working memory (backward Corsi), and math tasks to 43 children at the beginning of first grade (T1), at the end of first grade (T2), and at the end of second grade (T3). Math tasks were select according (...) to the children’s age and their levels of formal education: the “Battery for the evaluation of numerical intelligence from 4 to 6 years of age” (BIN 4–6) at T1 to test early numerical competence and the “Test for the evaluation of calculating and problem-solving abilities” (AC-MT 6–11) to test math skills at T2 and T3. Three regression models, in which the predictors were identified through a forward selection based on the use of the Bayesian information criterion (BIC) index, were performed to study the relationship between visual and spatial working memory and math ability at the three points in time. The results show that spatial working memory influences early numerical performance at T1, while early numerical performance is the unique predic-tor of math performance at T2. At the end of the second grade, the regression model reveals a relationship between math performance and both visual and spatial working memory and the attenuation of the importance of domain-specific predictors. The study depicts the dif-ferent implications of visual and spatial working memory predictors over the children’s de-velopment periods and brings additional evidence to the debate on the relationship between visuospatial working memory and math ability in young children. (shrink)

Many have held that when a person visually attends to an object, her visual system deploys a representation that designates the object. Call the referential link between such representations and the objects they designate attentive visual reference. In this article I offer an account of attentive visual reference. I argue that the object representations deployed in visual attention—which I call attentive visual object representations —refer directly, and are akin to indexicals. Then I turn to the (...) issue of how the reference of an AVOR is determined relative to a context. After raising problems for existing accounts, I propose a mechanism of reference determination that is both causal and descriptive: For an AVOR to refer to a particular object, the object must appropriately cause the deployment of the AVOR, and the AVOR must be associated with descriptive information about some of the object's geometrical and mereological properties. (shrink)

Evidence from adult studies of deaf signers supports the dissociation between neural systems involved in processing visual linguistic and non-linguistic body actions. The question of how and when this specialization arises is poorly understood. Visual attention to these forms is likely to change with age and be affected by prior language experience. The present study used eye-tracking methodology with infants and children as they freely viewed alternating video sequences of lexical American sign language (ASL) signs and non-linguistic body (...) actions (self-directed grooming action and object-directed pantomime). In Experiment 1, we quantified fixation patterns using an area of interest (AOI) approach and calculated face preference index (FPI) values to assess the developmental differences between 6 and 11-month-old hearing infants. Both groups were from monolingual English-speaking homes with no prior exposure to sign language. Six-month-olds attended the signer’s face for grooming; but for mimes and signs, they were drawn to attend to the “articulatory space” where the hands and arms primarily fall. Eleven-month-olds, on the other hand, showed a similar attention to the face for all body action types. We interpret this to reflect an early visual language sensitivity that diminishes with age, just before the child’s first birthday. In Experiment 2, we contrasted 18 hearing monolingual English-speaking children (mean age of 4.8 years) vs. 13 hearing children of deaf adults (CODAs; mean age of 5.7 years) whose primary language at home was ASL. Native signing children had a significantly greater face attentional bias than non-signing children for ASL signs, but not for grooming and mimes. The differences in the visual attention patterns that are contingent on age (in infants) and language experience (in children) may be related to both linguistic specialization over time and the emerging awareness of communicative gestural acts. (shrink)

Although the study of visual perception has made more progress in the past 40 years than any other area of cognitive science, there remain major disagreements as to how closely vision is tied to general cognition. This paper sets out some of the arguments for both sides and defends the position that an important part of visual perception, which may be called early vision or just vision, is prohibited from accessing relevant expectations, knowledge and utilities - in other (...) words it is cognitively impenetrable. That part of vision is complex and articulated and provides a representation of the 3-D surfaces of objects sufficient to serve as an index into memory, with somewhat different outputs being made available to other systems such as those dealing with motor control. The paper also addresses certain conceptual and methodological issues, including the use of signal detection theory and event-related potentials to assess cognitive penetration of vision. A distinction is made among several stages in visual processing. These include, in addition to the inflexible early-vision stage, a pre-perceptual attention allocation stage and a post-perceptual evaluation, memory-accessing, and inference stage which provide several different highly constrained ways in which cognition can affect the outcome of visual perception. The paper discusses arguments that have been presented in both computer vision and psychology showing that vision is "intelligent" and involves elements of problem solving". It is suggested that these cases do not show cognitive penetration, but rather they show that certain natural constraints on interpretation, concerned primarily with optical and geometrical properties of the world, have been compiled into the visual system. The paper also examines a number of examples where instructions and "hints" are alleged to affect. (shrink)

Visual self-recognition is often controversially cited as an indicator of self-awareness and assessed with the mirror-mark test. Great apes and humans, unlike small apes and monkeys, have repeatedly passed mirror tests, suggesting that the underlying brain processes are homologous and evolved 14-18 million years ago. However, neuroscientific, developmental, and clinical dissociations show that the medium used for self-recognition (mirror vs photograph vs video) significantly alters behavioral and brain responses, likely due to perceptual differences among the different media and prior (...) experience. On the basis of this evidence and evolutionary considerations, we argue that the visual self-recognition skills evident in humans and great apes are a byproduct of a general capacity to collate representations, and need not index other aspects of self-awareness. (shrink)

According to the Self-Location Thesis, certain types of visual experiences have self-locating and so first-person, spatial contents. Such self-locating contents are typically specified in relational egocentric terms. So understood, visual experiences provide support for the claim that there is a kind of self-consciousness found in experiential states. This paper critically examines the Self-Location Thesis with respect to dynamic-reflexive visual experiences, which involve the movement of an object toward the location of the perceiving subject. The main aim of (...) this paper is to offer an alternative interpretation of these cases which resists attributing them self-locating content, arguing for a replacement of the de se component with a non-conceptual equivalent of the indexical ‘here’. In its final section, the paper also considers an extension of the h-replacement account to cases of visual kinesthesis. (shrink)

Marr (1982) may have been one of the rst vision researchers to insist that in modeling vision it is important to separate the location of visual features from their type. He argued that in early stages of visual processing there must be “place tokens” that enable subsequent stages of the visual system to treat locations independent of what specic feature type was at that location. Thus, in certain respects a collinear array of diverse features could still be (...) perceived as a line, and under certain conditions could function as such in perceptual phenomena like the Poggendorf illusion. (shrink)

The aim of this paper is to analyse and compare the graphic elements present on book covers published in Croatia from 2012 to 2018, and compare the data with the graphic elements on book covers from five other European book markets. Hofstede’s model of cultural dimensions was used in the research to examine the ways in which the design of book covers is influenced by culture. The graphic elements on book covers from Croatia and a sample of five European countries (...) were compared using the visual content analysis method. Element frequency scores were correlated with indexes from Hofstede’s model of national culture and interpreted on the basis of the existing literature using the chi-squared test. Both the quantitative and qualitative analyses were carried out on the sample of 633 book covers. (shrink)

My purpose is to take a close look at the nature of visual content. I discuss the view that visual experiences have only existential contents, the view that visual experiences have either singular or gappy contents, and the view that visual experiences have multiple contents. I also consider a proposal about visual content inspired by Kaplan's well known theory of indexicals. I draw out some consequences of my discussion for the thesis of intentionalism with respect (...) to the phenomenal character of visual experience. (shrink)

Eye movements during mental imagery are not epiphenomenal but assist the process of image generation. Commands to the eyes for each fixation are stored along with the visual representation and are used as spatial index in a motor‐based coordinate system for the proper arrangement of parts of an image. In two experiments, subjects viewed an irregular checkerboard or color pictures of fish and were subsequently asked to form mental images of these stimuli while keeping their eyes open. During the (...) perceptual phase, a group of subjects was requested to maintain fixation onto the screen's center, whereas another group was free to inspect the stimuli. During the imagery phase, all of these subjects were free to move their eyes. A third group of subjects (in Experiment 2) was free to explore the pattern but was requested to maintain central fixation during imagery. For subjects free to explore the pattern, the percentage of time spent fixating a specific location during perception was highly correlated with the time spent on the same (empty) locations during imagery. The order of scanning of these locations during imagery was correlated to the original order during perception. The strength of relatedness of these scanpaths and the vividness of each image predicted performance accuracy. Subjects who fixed their gaze centrally during perception did the same spontaneously during imagery. Subjects free to explore during perception, but maintaining central fixation during imagery, showed decreased ability to recall the pattern. We conclude that the eye scanpaths during visual imagery reenact those of perception of the same visual scene and that they play a functional role. (shrink)

My purpose is to take a close look at the nature of visual content. I discuss the view that visual experiences have only existential contents, the view that visual experiences have either singular or gappy contents, and the view that visual experiences have multiple contents. I also consider a proposal about visual content inspired by Kaplan's well known theory of indexicals. I draw out some consequences of my discussion for the thesis of intentionalism with respect (...) to the phenomenal character of visual experience. (shrink)

There are no established conventions for, and few examples of, indexing visual material on the basis of its form. Most image databases use keywords to describe the form or function, and access data by text-based retrieval of these keywords. An image-based approach would order the data by appearance, e.g. Shepherd (1971) and Dreyfuss (1972). A taxonomy must be created in order to apply this technique to a new data set. Previous applications have been aided by certain limiting factors (...) on the possible range of images indexed thus providing the key to a taxonomy, e.g. international pictorial signs in Dreyfuss. A fundamental principle which may be inferred from these studies is that the taxonomy needs to be related to the needs of the user, and not solely to abstract features of design. This is reflected in guidelines issued by the UK organisation The Society of Indexers. The studies also suggest the need for several approaches to classification within the same data set, e.g Dreyfuss, in which signs are located under more than one heading. (shrink)