Mental representations remain the central posits of psychology after many decades of scrutiny. However, there is no consensus about the representational format(s) of biological cognition. This paper provides a survey of evidence from computational cognitive psychology, perceptual psychology, developmental psychology, comparative psychology, and social psychology, and concludes that one type of format that routinely crops up is the language-of-thought (LoT). We outline six core properties of LoTs: (i) discrete constituents; (ii) role-filler independence; (iii) predicate–argument structure; (iv) logical operators; (v) inferential (...) promiscuity; and (vi) abstract content. These properties cluster together throughout cognitive science. Bayesian computational modeling, compositional features of object perception, complex infant and animal reasoning, and automatic, intuitive cognition in adults all implicate LoT-like structures. Instead of regarding LoT as a relic of the previous century, researchers in cognitive science and philosophy-of-mind must take seriously the explanatory breadth of LoT-based architectures. We grant that the mind may harbor many formats and architectures, including iconic and associative structures as well as deep-neural-network-like architectures. However, as computational/representational approaches to the mind continue to advance, classical compositional symbolic structures – that is, LoTs – only prove more flexible and well-supported over time. (shrink)

There is ongoing debate about whether number is perceived directly. Clarke and Beck suggest that what plagues this debate is a lack of shared understanding about what it means to perceive number in the first place. I agree. I argue that the perception of number is held to a different standard than, say, the perception of objecthood; considering this, I explore what it might mean for the number system to represent rational numbers.

In the philosophy of perception, typically, everything is illuminated. Discussions of perceptual experience primarily focus on subjects situated in illuminated environs. Rarely do we see treatment of putative perceptual experience involving darkness. In this paper, I will carefully canvas and characterize the nature of experiences of darkness, marking a substantive distinction between two such kinds of experiences. Crucially, I give an account of the distinctive phenomenology of experiences of darkness, and show that neither of the two broad kinds of experiences (...) of darkness requires, as Roy Sorensen has recently suggested, the reification of unfamiliar entities to serve as objects of perceptual awareness. I will also offer potential candidates for the proper representational contents of experiences of darkness. This exploration not only reveals that such experiences pose no threat to a view like representationalism, but also demonstrates how experiences of darkness can be given their rightful place in a naturalistic theory of perceptual awareness. Atlast, darkness will be brought out from the shadows. A dungeon horrible, on all sides round, As one great furnace flamed, yet from those flames No light; but rather darkness visible ? ?John Milton, Paradise Lost. (shrink)

Because the visual system cannot process all of the objects, colors, and features present in a visual scene, visual attention allows some visual stimuli to be selected and processed over others. Most research on visual attention has focused on spatial or location-based attention, in which the locations occupied by stimuli are selected for further processing. Recent research, however, has demonstrated the importance of objects in organizing (or segregating) visual scenes and guiding attentional selection. Because of the long history of spatial (...) attention research, theories of spatial attention are more mature than theories of other visual processes, such as object segregation and object attention. In the present paper, I outline a biased competition account of object segregation and attention, following similar accounts that have been developed for spatial attention (Desimone and Duncan, 1995). In my biased competition account, I seek to understand how some objects can be segregated and selected over other objects in a complex visual scene. Under this account, there are two sources of visual information that allow an object to be processed over other objects: bottom-up information carried by the physical stimulus and top-down information based on an observer's goals. I use the biased competition account to combine many diverse findings from the object segregation and attention literatures into a common framework. (shrink)

Neuropsychological deficits have been widely used to elucidate normal cognitive functioning. Can patients with such deficits also be used to understand conscious visual experience? In this paper, we ask what it would be like to be a patient with apperceptive agnosia . Philosophical analyses of such questions have suggested that subjectively experiencing what another person experiences would be impossible. Although such roadblocks into the conscious experience of others exist, the experimental study of both patients and neurologically normal subjects can be (...) used to understand visual processing mechanisms. In order to understand the visual processes damaged in apperceptive agnosia, we first review this syndrome and present a case study of one such patient, patient J.W. We then review several theoretical accounts of apperceptive agnosia, and we conclude that studies of the patients themselves may not allow us to discriminate between the various explanations of the syndrome. To test these accounts, we have simulated apperceptive agnosia in neurologically normal subjects. The implications of our results for understanding both apperceptive agnosia and normal visual processing are discussed. (shrink)

Previous accounts of how people develop expertise have focused on how deliberate practice transforms the cognitive and perceptual representations and processes that give rise to expertise. However, the likelihood of developing expertise with a particular tool may also depend on the degree to which that tool fits pre‐existing perceptual and cognitive abilities. The present studies explored whether the abacus—a descendent of the first human computing devices—may have evolved to exploit general biases in human visual attention, or whether developing expertise with (...) the abacus requires learning special strategies for allocating visual attention to the abacus. To address this question, we administered a series of visual search tasks to abacus experts and subjects who had little to no abacus experience, in which search targets and distractors were overlaid atop abacus “beads.” Across three studies, we found that both experts and naïve subjects were faster to detect targets in semantically relevant components of the abacus, suggesting that abacus training is not required to exhibit attentional biases toward these components of the abacus. This finding suggests that the attentional biases that scaffold numerical processing of the abacus may emerge from general properties of visual attention that are exploited by the design of the abacus itself. (shrink)

Consciousness researchers are interested in distinguishing between mental activity that occurs with and without awareness . The inattentional blindness paradigm is an excellent tool for this question because it permits the independent manipulation of processing time and awareness. In the present study, we show that implicit texture segregation can occur during inattentional blindness, provided that the texture is exposed for a sufficient duration. In contrast, a Simon effect does not occur during inattentional blindness, even with similar exposure duration of the (...) critical stimulus. This reveals a dissociation between processing time and awareness, consistent with the possibility of separate processing streams for explicit and implicit visual perception. (shrink)

The notion that visual attention can operate over visual objects in addition to spatial locations has recently received much empirical support, but there has been relatively little empirical consideration of what can count as an `object' in the ®rst place. We have investi- gated this question in the context of the multiple object tracking paradigm, in which subjects must track a number of independently and unpredictably moving identical items in a ®eld of identical distractors. What types of feature clusters can (...) be tracked in this manner? In other words, what counts as an `object' in this task? We investigated this question with a technique we call target merging: we alter tracking displays so that distinct target and distractor loca- tions appear perceptually to be parts of the same object by merging pairs of items (one target with one distractor) in various ways ± for example, by connecting item locations with a simple line segment, by drawing the convex hull of the two items, and so forth. The data show that target merging makes the tracking task far more dif®cult to varying degrees depending on exactly how the items are merged. The effect is perceptually salient, involving in some conditions a total destruction of subjects' capacity to track multiple items. These studies provide strong evidence for the object-based nature of tracking, con®rming that in some contexts attention must be allocated to objects rather than arbitrary collections of features. In addition, the results begin to reveal the types of spatially organized scene components that can be independently attended as a function of properties such as connectedness, part struc- ture, and other types of perceptual grouping. q 2001 Elsevier Science B.V. All rights reserved. (shrink)

The thesis that the visual system represents objects has garnered empirical support from a variety of sources in recent decades. But what kinds of things qualify as “objects” in the relevant sense? Are they ordinary three-dimensional bodies? Are they the facing surfaces of three-dimensional bodies? I argue that there is no fact of the matter: what we have are equally acceptable ways of assigning extensions to the relevant visual states. The view I defend bears obvious similarities to Quine’s thesis that (...) linguistic reference is inscrutable. Importantly, though, I argue that even if Quine was wrong about inscrutability as a thesis about language and thought, the case for the inscrutability of visual reference remains strong. (shrink)

The goal of perceptual systems is to allow organisms to adaptively respond to ecologically relevant stimuli. Because all perceptual inputs are ambiguous, perception needs to rely on prior knowledge accumulated over evolutionary and developmental time to turn sensory energy into information useful for guiding behavior. It remains controversial whether the guidance of perception extends to cognitive states or is locked up in a “cognitively impenetrable” part of perception. I argue that expectations, knowledge, and task demands can shape perception at multiple (...) levels, leaving no part untouched. The position advocated here is broadly consistent with the notion that perceptual systems strive to minimize prediction error en route to globally optimal solutions :181–204, 2013). On this view, penetrability should be expected whenever constraining lower-level processes by higher level knowledge is minimizes global prediction error. Just as Fodor feared cognitive penetration of perception threatens theory-neutral observation and the distinction between observation and inference. However, because theories themselves are constrained by the task of minimizing prediction error, theory-laden observation turns out to be superior to theory-free observation in turning sensory energy into useful information. (shrink)

How are attention and consciousness related? Can we learn what the contents of someone’s consciousness are if we know the targets of their attention? What can we learn about the contents of consciousness if we know the targets of attention? Although introspection might suggest that attention and consciousness are intimately connected, a good body of recent findings in cognitive psychology and cognitive neuroscience brings compelling reasons to believe that they are two separate and independent processes. This paper attempts to bring (...) attention and consciousness back together to make the study of attentional distributions an essential ingredient for the study of the contents of consciousness. My proposal has two main components. First, I introduce a framework for systematizing the relations between attention in its different forms and consciousness in its different forms. Although philosophers and cognitive scientists have repeatedly highlighted the importance of such systematization, most details are still to be worked out. Here I take an initial stab at this project based on the notion of degrees of informational enhancement. Second, I introduce the notion of vicarious attention to account for a kind of additional processing benefit that comes for free when attention is allocated to a target. I then propose that this kind of processing must also be considered when mapping attention targets into contents of consciousness. (shrink)

We pose a foundational problem for those who claim that subjects are ontologically irreducible, but causally reducible (weak emergence). This problem is neuroscience’s notorious binding problem, which concerns how distributed neural areas produce unified mental objects (such as perceptions) and the unified subject that experiences them. Synchrony, synapses and other mechanisms cannot explain this. We argue that this problem seriously threatens popular claims that mental causality is reducible to neural causality. Weak emergence additionally raises evolutionary worries about how we’ve survived (...) the perils of nature. Our emergent subject hypothesis (ESH) avoids these shortcomings. Here, a singular, unified subject acts back on the neurons it emerges from and binds sensory features into unified mental objects. Serving as the mind’s controlling center, this subject is ontologically and causally irreducible (strong emergence). ESH draws on recent experimental evidence, including the motivation of a possible correlate (or “seat”) of the subject, which enhances its testability. (shrink)

Neuropsychological studies suggest the existence of lateralized networks that represent categorical and coordinate types of spatial information. In addition, studies with neural networks have shown that they encode more effectively categorical spatial judgments or coordinate spatial judgments, if their input is based, respectively, on units with relatively small, nonoverlapping receptive fields, as opposed to units with relatively large, overlapping receptive fields. These findings leave open the question of whether interactive processes between spatial detectors and types of spatial relations can be (...) modulated by spatial attention. We hypothesized that spreading the attention window to encompass an area that includes two objects promotes coordinate spatial relations, based on coarse coding by large, overlapping, receptive fields. In contrast, narrowing attention to encompass an area that includes only one of the objects benefits categorical spatial relations, by effectively parsing space. By use of a cueing procedure, the spatial attention window was manipulated to select regions of differing areas. As predicted, when the attention window was large, coordinate spatial transformations were noticed faster than categorical transformations; in contrast, when the attention window was relatively smaller, categorical spatial transformations were noticed faster than coordinate transformations. Another novel finding was that coordinate changes were noticed faster when cueing an area that included both objects as well as the empty space between them than when simultaneously cueing both areas including the objects while leaving the gap between them uncued. (shrink)

Visual attentional processes have been an important topic in psychological research for years. Over the last few decades, new methods have been developed, aiming to explore the characteristics of the focus of attention in more detail. Studies that applied the “Attention-Window Task” quantified the maximum extent of the “Attention Window” along its horizontal, vertical, and diagonal meridians, when subjects were required to perceive two peripheral stimuli simultaneously. In three experiments using the AWT, we investigated the effects of cue validity, stimulus-onset (...) asynchrony, and target stimuli complexity on the size and shape of the AW. Results showed that the AW was greater under valid cue conditions compared to invalid conditions, when the locations of cue and target stimuli differed. Furthermore, the AW decreased when the SOA between the cue and targets was reduced and also when the task complexity was higher and more objects within the target stimuli had to be classified. Overall, it can be stated that the AWT with its possible task changes and adjustments can be considered as a potential standard tool to measure the maximum spread and shape of the spatial AW. (shrink)

We present work demonstrating that the nature of an object for our visual system depends on the actions we are programming and on the presence of action relations between stimuli. For example, patients who show visual extinction are more likely to become aware of two objects if the objects fall in appropriate visual locations for a common action. This effect of the action relations between objects is modulated both by the familiarity of the positioning of the objects for action, and (...) by the mere possibility of action (the ‘affordance’) between the objects. In addition, the programming of an action to a part of an object alters the representation of that object, making the ‘part’ into the object selected by the visual system. These results point to object coding being a rather flexible process, affected not only by the perceptual properties of stimuli but also by the relations between these properties and action. We discuss the implications for theories of perception as well as considering why action information, in particular, may be important for perception. (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)

Looking at a pair of objects is easy when automatic grouping mechanisms bind these objects together, but visual exploration can also be more flexible. It is possible to mentally “re-group” two objects that are not only separate but belong to different pairs of objects. “Re-grouping” is in conflict with automatic grouping, since it entails a separation of each item from the set it belongs to. This ability appears to be impaired in patients with schizophrenia. Here we check if this impairment (...) is selective, which would suggest a dissociation between grouping and “re-grouping,” or if it impacts on usual, automatic grouping, which would call for a better understanding of the interactions between automatic grouping and “re-grouping.” Sixteen outpatients with schizophrenia and healthy controls had to identify two identical and contiguous target figures within a display of circles and squares alternating around a fixation point. Eye-tracking was used to check central fixation. The target pair could be located in the same or separate hemifields. Identical figures were grouped by a connector (grouped automatically) or not (to be re-grouped). Attention modulation of automatic grouping was tested by manipulating the proportion of connected and unconnected targets, thus prompting subjects to focalize on either connected or unconnected pairs. Both groups were sensitive to automatic grouping in most conditions, but patients were unusually slowed down for connected targets while focalizing on unconnected pairs. In addition, this unusual effect occurred only when targets were presented within the same hemifield. Patients and controls differed on this asymmetry between within- and acrosshemifield presentation, suggesting that patients with schizophrenia do not re-group figures in the same way as controls do.We discuss possible implications on how “re-grouping” ties in with ongoing, automatic perception in healthy volunteers. (shrink)

A common objection to representationalism is that a representationalist view of phenomenal character cannot accommodate the effects that shifts in covert attention have on visual phenomenology: covert attention can make items more visually prominent than they would otherwise be without altering the content of visual experience. Recent empirical work on attention casts doubt on previous attempts to advance this type of objection to representationalism and it also points the way to an alternative development of the objection.

Language is more than a source of information for accessing higher-order conceptual knowledge. Indeed, language may determine how people perceive and interpret visual stimuli. Visual processing in linguistic contexts, for instance, mirrors language processing and happens incrementally, rather than through variously-oriented fixations over a particular scene. The consequences of this atypical visual processing are yet to be determined. Here, we investigated the integration of visual and linguistic input during a reasoning task. Participants listened to sentences containing conjunctions or disjunctions and (...) looked at visual scenes containing two pictures that either matched or mismatched the nouns. Degree of match between nouns and pictures and between their expected and actual spatial positions affected fixations as well as judgments. We conclude that language induces incremental processing of visual scenes, which in turn becomes susceptible to reasoning errors during the language-meaning verification process. (shrink)