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Untrained Octopus vulgaris (observers) were allowed to watch conditioned Octopus (demonstrators) perform the task of selecting one of two objects that were presented simultaneously and differed only in color. After [...]

Immediate serial recall of visually presented verbal stimuli is impaired by the presence of irrelevant auditory background speech, the so-called irrelevant speech effect. Two of the three main accounts of this effect place restrictions on when it will be observed, limiting its occurrence either to items processed by the phonological loop (the phonological loop hypothesis) or to items that are not too dissimilar from the irrelevant speech (the feature model). A third, the object-oriented episodic record (O-OER) model, requires only that the memory task involves seriation. The present studies test these three accounts by examining whether irrelevant auditory speech will interfere with a task that does not involve the phonological loop, does not use stimuli that are compatible with those to be remembered, but does require seriation. Two experiments found that irrelevant speech led to lower levels of performance in a visual statistical learning task, offering more support for the O-OER model and posing a challenge for the other two accounts.

113 3-, 4-, 5-, and 6-yr.-old preschool children were administered the Bannatyne Visuospatial Memory test to obtain cross-sectional data on a downward extension of the test instrument. Means, standard deviations, and correlation coefficients for the sample as well as estimates of validity and reliability are reported. Analysis of variance for the number of correct matches indicated significant differences for age but not for sex. Results were consistent with previous findings and support the efficacy of this test in assessing motor-free visuospatial memory of preschool children as young as three.

An investigation is conducted to find how exposure duration at study and emotional content of an object affect the likelihood of remembering an item's specific visual details. Across two experiments, emotional content and negative arousing content enhanced the likelihood that specific visual details are remembered about an object.

Abstract This article presents one portrayal of the role of photography as a language of teacher inquiry. To inform teachers' use of photography, the first part of the article presents […]

A hallmark of perceptual expertise is that experts classify objects at a more specific, subordinate level of abstraction than novices. To what extent does subordinate-level learning contribute to the transfer of perceptual expertise to novel exemplars and novel categories? In this study, participants learned to classify 10 varieties of wading birds and 10 varieties of owls at either the subordinate, species (e.g., 'great blue crown heron,''eastern screech owl') or the family ('wading bird,''owl') level of abstraction. During training, the amount of visual exposure was equated such that participants received an equal number of learning trials for wading birds and owls. Pre- and posttraining performance was measured in a same/different discrimination task in which participants judged whether pairs of bird stimuli belonged to the same or different species. Participants trained in species-level discrimination demonstrated greater transfer to novel exemplars and novel species categories than participants trained in family-level discrimination. These findings suggest that perceptual categorization, not perceptual exposure per se, is important for the development and generalization of visual expertise.

Statistical learning has been widely proposed as a mechanism by which observers learn to decompose complex sensory scenes. To determine how robust statistical learning is, we investigated the impact of attention and perceptual grouping on statistical learning of visual shapes. Observers were presented with stimuli containing two shapes that were either connected by a bar or unconnected. When observers were required to attend to both locations at which shapes were presented, the degree of statistical learning was unaffected by whether the shapes were connected or not. However, when observers were required to attend to just one of the shapes' locations, statistical learning was observed only when the shapes were connected. These results demonstrate that visual statistical learning is not just a passive process. It can be modulated by both attention and connectedness, and in natural scenes these factors may constrain the role of stimulus statistics in learning.

A study was conducted to examine the role of a prominent visual cue in spatial learning. The prominent visual cue served as a directional cue that competed with other directional cues, in the unfamiliar environment and interfered with performances.

Researchers have found evidence that the representation of auditory and tactile information in the brains of blind people shows strong similarities to the way in which visual information is represented [...]

One of the most familiar empirical phenomena associated with face recognition is the cross-race (CR) recognition deficit whereby people have difficulty recognizing members of a race different from their own. Most researchers assume that the CR deficit is caused by failure to generalize perceptual encoding expertise from same-race (SR) faces to CR faces. However, this explanation ignores critical differences in the social cognitions and feature coding priorities associated with SR and CR faces. On the basis of data from visual search and perceptual discrimination tasks, it appears that the deficit occurs because people emphasize visual information specifying race at the expense of individuating information when recognizing CR faces. In particular, it is possible to observe a paradoxical improvement in both detection and perceptual discrimination accuracy for CR faces that is limited to those who recognize them poorly. These findings support a new explanation for the CR recognition deficit based on feature coding differences between CR and SR faces, and appear incompatible with similarity-based models of face categories.

Advances in neuroscience implicate reentrant signaling as the predominant form of communication between brain areas. This principle was used in a series of masking experiments that defy explanation by feed-forward theories. The masking occurs when a brief display of target plus mask is continued with the mask alone. Two masking processes were found: an early process affected by physical factors such as adapting luminance and a later process affected by attentional factors such as set size. This later process is called masking by object substitution, because it occurs whenever there is a mismatch between the reentrant visual representation and the ongoing lower level activity. Iterative reentrant processing was formalized in a computational model that provides an excellent fit to the data. The model provides a more comprehensive account of all forms of visual masking than do the long-held feed-forward views based on inhibitory contour interactions.

When learning task involved visualization of dynamic processes, different working capability of short-term memory and the use of viewing strategies among learners should be considered. The study was to explore gender differences in learning and strategy use when different visual controls (self-controlled vs. system-controlled) were provided. From a 2 x 2 ANOVA test, the main effects were both significant for visual control (p [is less than] 0.05) and gender difference (p [is less than] 0.05). Among boys who used covert strategies for processing visual information, the difference between treatments is significant (p [is less than] 0.05). However, among girls who used overt strategies, the difference is insignificant (p [is greater than] 0.05)., INTRODUCTION In computer-based learning environment, strategies that students employ in the dynamic multimedia learning environment are essential for associating and extracting relevant internal or external concepts. Whether gender differences exist [...]

The purpose of this research was to investigate the effects of active exercise of the arms on various physiological, perceptual, and cognitive parameters of children with spina bifida manifesta who were aged 9 to 12 yr. Following a 5-min. rest interval, subjects were either not exercised (control days) for a 6-min. period or were exercised (experimental days) for a 6-min. period. Cardiac measures, respiratory function, peripheral vision, and figural learning trials were recorded after exercise. Wilcoxon matched-pairs signed rank tests were computed on the means of the exercise and no-exercise conditions for each measure. Six minutes of active exercise resulted in significant increases in peripheral vision, respiratory and cardiac measures and significant decreases in figural learning trials for these children. A floor effect was noted for the figural learning test. It was concluded that exercise increased blood flow through the lungs allowing for greater oxygen diffusion in the brain and other facilitatory effects resulting in more effective cerebral activity. Curriculum revisions for such children seem to indicate the importance of activity in facilitating subsequent learning.

In three experiments, pigeons were trained to discriminate between uniform arrays of two elements that differed in color, form, or size. They were then tested with arrays that contained different proportions of the two elements on these dimensions. In all cases, orderly discrimination gradients reflected these proportions. The discrimination readily transferred to new arrays with similar stimuli, but with different total numbers of elements. In Experiment 4, the pigeons were taught to discriminate between two groups of categorical stimuli: pictures of birds and pictures of flowers. A test with different proportions of each again produced a gradient based on realtive numerosity. Experiment 5 demonstrated transfer of stimulus control on the numerosity dimension when pigeons were trained with one set of instances from two categories, and then were tested with new instances from the same categories.

The ability to solve tactual oddity problems, and transfer of oddity learning across the visual and the tactual modalities, was studied in 3- to 8-year-old children (N = 294). Oddity tasks consisting of one odd and two equal objects were made from stimuli that were easily discriminated visually and tactually. The results showed that tactual oddity learning increased gradually with age. The growth in tactual performance begins later than visual, suggesting that children are more adept at encoding visual stimulus invariances or relational properties than tactual ones. Bidirectional cross-modal transfer of oddity learning was found, supporting the suggestion that such transfer occurs when training and transfer oddity tasks share a common vehicle dimension. The cross-modal effect also shows that oddity learning is independent of a specific modality-labeled perceptual context. Our results are consistent with the view that development of oddity learning depends on a single rather than a dual process, and that the oddity relation may be treated as an amodal stimulus feature.

A Definition of Visual Literacy Jean Trumbo. 1999. 'Visual Literacy and Science Communication.' Science Communication, Vol. 20. No. 4, pp. 409-425; Visual literacy is defined as a holistic construct that [...]

Pylyshyn's effort in establishing the cognitive impenetrability of early vision is welcome. However, his view about the role of attention in early vision seems to be oversimplified. The allocation of focal attention manifests its effect among multiple stages in the early vision system, it is not just confined to the input and the output levels.

The target article claimed that although visual apprehension involves all of general cognition, a significant component of vision (referred to as early vision) works independently of cognition and yet is able to provide a surprisingly high level interpretation of visual inputs, roughly up to identifying general shape-classes. The commentators were largely sympathetic, but frequently disagreed on how to draw the boundary, on exactly what early vision delivers, on the role that attention plays, and on how to interpret the neurophysiological data showing top-down effects. A significant number simply asserted that they were not willing to accept any distinction between vision and cognition, and a surprising number even felt that we could never tell for sure, so why bother? Among the topics covered was the relation of cognition and consciousness, the relation of early vision to other modules such as face recognition and language, and the role of natural constraints.

It is argued that the alleged cases of cognitive penetration of visual modules actually arise from the integration of information among different modules. This would reflect a general computational strategy, according to which constraints to a particular module would be provided by information coming from different modules. Examples are provided from the integration of stereopsis and occlusion and from computation of motion direction.

Expert perceivers may learn more than just where to apply visual processing, or which part of the output from the visual system to attend to. Their early visual system may be modified, as a result of their specific needs, through a process of early visual learning. We argue that this is, in effect, a form of long-term, indirect cognitive penetration of early vision.

The commentator agrees with Pylyshyn's most general claims but sees problems with the more specific proposals about where the boundary between early vision and later processing might lie. The boundary cuts across current models of identification. Limitations in current research on scenic context effects preclude firm conclusions. High-level vision will benefit more from integrative work than from premature analysis.

We argue that cognitive penetration in non-early vision extends beyond the special situations considered by Pylyshyn. Many situations which do not involve difficult stimuli or require expert skills nevertheless load on high-level cognitive processes. School learning effects illustrate this point: they provide a way to observe task dissociations which support the discontinuity hypothesis, but they show that the scope of visual cognition in our visual experience is often underestimated.

Pylyshyn defends a distinction between early visual perception and cognitive processing. But exactly where should the line between vision and cognition be drawn? Our research on object identification suggests that the construction of an object's visual description is isolated from contextually derived expectations. Moreover, the matching of constructed descriptions to stored descriptions appears to be similarly isolated.

We question the usefulness of Pylyshyn's dichotomy between cognitively penetrable and cognitively impenetrable mechanisms as the basis for his distinction between cognition and early vision. This dichotomy is comparable to others that have been proposed in psychology prompting disputes that by their very nature could not be resolved. This fate is inevitable for Pylyshyn's thesis because of its reliance on internal representations and their interpretation. What is more fruitful in relation to this issue is not a difficult dichotomy, but a different look at perception such as proposed by Gibson (1979).

According to Pylyshyn, the early visual system is able to categorize perceptual inputs into shape classes based on visual similarity criteria; it is also suggested that written words may be categorized within early vision. This speculation is contradicted by the fact that visually unrelated exemplars of a given letter (e.g., a/A) or word (e.g., read/READ) map onto common visual categories.

Cognitive impenetrability (CI) of a large part of visual perception is taken for granted by those of us in the field of computational vision who attempt to recover descriptions of space using geometry and statistics as tools. These tools clearly point out, however, that CI cannot extend to the level of structured descriptions of object surfaces, as Pylyshyn suggests. The reason is that visual space - the description of the world inside our heads - is a nonEuclidean curved space. As a consequence, the only alternative for a vision system is to develop several descriptions of space-time; these are representations of reduced intricacy and capture partial aspects of objective reality. As such, they make sense in the context of a class of tasks/actions/plans/purposes, and thus cannot be cognitively impenetrable.

We amplify possible complications to the tidy division between early vision and later categorisation which arise when we consider the perception of human faces. Although a primitive face-detecting system, used for social attention, may indeed be integral to 'early vision,' the relationship between this and diverse other uses made of information from faces is far from clear.

This commentary discusses Pylyshyn's model of perceptual processing in the light of the philosophical distinction between the conceptual and the nonconceptual content of perception. Pylyshyn's processing distinction maps onto an important distinction in the phenomenology of visual perception.