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This descriptive cross-sectional research sought to investigate the learning styles of 84 undergraduate and 21 graduate students at The University of the West Indies, Mona, Jamaica. Fleming's visual-auditory-kinaesthetic (VAK) learning-style inventory was used to collect data. The results revealed that the students were multisensory learners, with the visual learning style being the dominant style of learning. The students who used auditory learning styles were more likely to use kinaesthetic learning styles as well. Graduate students reported a higher rate of auditory learning styles than undergraduate students. The results of the findings suggest that facilitating multisensory learning styles in teaching and learning would be more beneficial to students. Keywords: learning styles, teaching and learning, tertiary students. Cette recherche descriptive transversale visait a etudier les methodes d'apprentissage de 84 etudiants de premier cycle et de 21 etudiants de deuxieme cycle a l'Universite des West Indies, a Mona, en Jamaique. L'inventaire des methodes d'apprentissage--visuel, auditif et kinesthesique (VAK)--de Fleming a ete utilise pour collecter les donnees. Les resultats ont revele que les etudiants etaient des apprenants multisensoriels, la methode d'apprentissage visuelle etant le style d'apprentissage dominant. Les etudiants qui utilisent des methodes d'apprentissage auditives sont plus susceptibles d'utiliser egalement des styles d'apprentissage kinesthesiques. Les etudiants de deuxieme cycle ont signale un taux plus eleve de styles d'apprentissage auditifs que les etudiants de premier cycle. Les resultats de l'etude suggerent que la facilitation des styles d'apprentissage multisensoriels dans l'enseignement et l'apprentissage serait plus benefique pour les etudiants. Mots-cles: methodes d'apprentissage, enseignement et apprentissage, etudiants. Esta investigacion descriptiva transversal tuvo por objetivo investigar los estilos de aprendizaje de 84 estudiantes de pregrado y 21 estudiantes de posgrado en la Universidad de West Indies, Mona, Jamaica. Se utilizo el inventario de estilo de aprendizaje visual-auditivo-cinestesico (VAK) de Fleming para recopilar datos. Los resultados revelaron que los estudiantes eran aprendices multisensoriales, y que el estilo de aprendizaje visual era el estilo dominante de aprendizaje. Los estudiantes que usaron estilos de aprendizaje auditivo tambien tenian mas probabilidades de usar estilos de aprendizaje cinestesico. Los estudiantes de posgrado reportaron una mayor tasa de estilos de aprendizaje auditivo que los estudiantes de pregrado. Los resultados de los hallazgos sugieren que facilitar los estilos de aprendizaje multisensoriales en el proceso de ensenanza-aprendizaje seria mas beneficioso para los estudiantes. Palabras clave: estilos de aprendizaje, ensenanza y aprendizaje, estudiantes terciarios., INTRODUCTION Understanding students' preferred learning styles will help educators to take full advantage of the appropriate teaching methodologies that best facilitate students' success (Fesol et al. 2016). Students who are [...]

Purpose: Two studies examined learning of grammar-like visual sequences to determine whether a general deficit in statistical learning characterizes this population. Furthermore, we tested the hypothesis that difficulty in sustaining attention during the learning task might account for differences in statistical learning. Method: In Study 1, adults with normal language (NL) or language-learning disability (LLD) were familiarized with the visual artificial grammar and then tested using items that conformed or deviated from the grammar. In Study 2, a 2nd sample of adults with NL and LLD were presented auditory word pairs with weak semantic associations (e.g., groom + clean) along with the visual learning task. Participants were instructed to attend to visual sequences and to ignore the auditory stimuli. Incidental encoding of these words would indicate reduced attention to the primary task. Results: In Studies 1 and 2, both groups demonstrated learning and generalization of the artificial grammar. In Study 2, neither the NL nor the LLD group appeared to encode the words presented during the learning phase. Conclusion: The results argue against a general deficit in statistical learning for individuals with LLD and demonstrate that both NL and LLD learners can ignore extraneous auditory stimuli during visual learning. Key Words: adults, language, language disorders, procedural learning, statistical learning, An individual's ability to detect statistical regularities in their environment plays an important role in perceptual and cognitive learning, including language acquisition, skill learning, and object recognition. Recognition of statistical [...]

Fast-mapping paradigms have not been used previously to examine the process of word learning in boys with fragile X syndrome (FXS), who are likely to have intellectual impairment, language delays, and symptoms of autism. In this study, a fast-mapping task was used to investigate associative word learning in 4- to 10-year-old boys with FXS relative to younger typically developing boys and age-matched boys with autism spectrum disorders (ASD). Task performance exceeded chance levels for all groups; however, boys with FXS outperformed boys with ASD, despite having lower levels of nonverbal cognition. Memory task demands significantly impacted performance only for boys with typical development. For boys with FXS or ASD, fast-mapping uniquely accounted for small but significant variance in concurrent levels of vocabulary comprehension as did chronological age and nonverbal IQ, but not autism severity. Understanding the fast-mapping process has implications for designing interventions to support word learning and language acquisition in these populations. Keywords Autism * Fragile X syndrome * Fast-mapping * Language development * Vocabulary, Introduction Fragile X syndrome (FXS) is the leading inherited cause of intellectual disability (Fernandez-Carvajal et al. 2009; Hagerman 2008) and the most common single-gene cause of autism (Feinstein and Reiss [...]

Learning theories hypothesize specific circuits encode essential information for performance. For simple tasks in invertebrates and mammals, the essential circuits are known, but for cognitive functions, the essential circuits remain unidentified. Here, we show that some essential information for performing a choice task is encoded in a specific circuit in a neocortical area. Rat postrhinal (POR) cortex is required for visual shape discriminations, protein kinase C (PKC) pathways mediate changes in neuronal physiology that support learning, and specific PKC genes are required for multiple learning tasks. We used direct gene transfer of a constitutively active PKC to prime a specific POR cortex circuit for learning visual shape discriminations. In the experiment, rats learned a discrimination, received gene transfer, learned new discriminations, received a small lesion that ablated [approximately equal to] 21% of POR cortex surrounding the gene transfer site, and were tested for performance for discriminations learned either before or after gene transfer. Lesions of the genetically targeted circuit selectively interfered with performance for discriminations learned after gene transfer. Activity-dependent gene imaging confirmed increased activity in the genetically targeted circuit during learning and showed the essential information was sparse-coded in [approximately equal to] 500 neurons in the lesioned area. Wild-type rats contained circuits with similar increases in activity during learning, but these circuits were located at unpredictable, different positions in POR cortex. These results establish that some essential information for performing specific visual discriminations can be encoded in a small, identified, neocortical circuit and provide a foundation for characterizing the circuit and essential information. learning | vision | protein kinase C | neocortex | herpes simplex virus vector doi/ 10.1073/pnas.0912950107

The acquisition of reading skills is a major landmark process in a human's cognitive development. On the neural level, a new functional network develops during this time, as children typically learn to associate the well-known sounds of their spoken language with unfamiliar characters in alphabetic languages and finally access the meaning of written words, allowing for later reading. A critical component of the mature reading network located in the left occipitotemporal cortex, termed the 'visual word-form system' (VWFS), exhibits print-sensitive activation in readers. When and how the sensitivity of the VWFS to print comes about remains an open question. In this study, we demonstrate the initiation of occipito-temporal cortex sensitivity to print using functional MRI (fMRI) (n = 16) and event-related potentials (ERP) (n = 32) in a controlled, longitudinal training study. Print sensitivity of fast ( learning/training/visual word-form system/functional MRI/ event-related potential doi/ 10.1073/pnas.0904402107

The purpose of this study was to examine the instructional effects of a computer-generated agent in providing verbal and visual prompts as needed to facilitate student achievement of educational objectives. Sixty-seven college students were randomly selected into two instructional treatment groups and a control group. Significant differences in achievement were found on the terminology and comprehension tests. Students receiving the animated pedagogical agent (teaching assistant) with visual prompts performed significantly better than those receiving verbal prompts and the text condition only. This study supports the notion of scaffolding in multimedia learning., INTRODUCTION Scaffolding as an instructional strategy for improving instruction has been explored across a range of disciplines in support of learning within the multimedia environment. The notion of scaffolding has [...]

This article reviews studies on variables that are related to the motor skill performance of children and adolescents with visual impairments (VI). Three major groups of variables are considered (child, environmental, and task). Thirty-nine studies are included in this review, 26 of which examined the effects of child, environmental, and/or task variable(s) on motor skill performance and 13 of which reported suggestions by experts about variables related to performance. Weak evidence was found for three relationships: (a) between the degree of VI and dynamic balance and manual dexterity, (b) between amblyopia/strabismus and fine motor skills, and (c) between movement interventions and motor skill performance. In addition, weak evidence was found to refute a relationship between gender and static balance. Further research with reliable and valid measurement instruments and theoretically funded research emphasizing the interaction between a wide range of variables is needed, with specific attention to environmental and task variables., Visual impairment (VI; i.e., low vision or blindness) has an impact on all aspects of a child's development (Warren, 1994). One specific concern to researchers and practitioners in the field [...]

The environment contains considerable information that is distributed across space and time, and the visual system is remarkably sensitive to such information via the operation of visual statistical learning (VSL). Previous VSL studies have focused on establishing what kinds of statistical relationships can be learned but have not fully explored how this knowledge is then represented in the mind. These representations could faithfully reflect the details of the learning context, but they could also be generalized in various ways. This was studied by testing how VSL transfers across changes between learning and test, and the results revealed a substantial degree of generalization. Learning of statistically defined temporal sequences was expressed in static spatial configurations, and learning of statistically defined spatial configurations facilitated detection performance in temporal streams. Learning of temporal sequences even transferred to reversed temporal orders during test when accurate performance did not depend on order, per se. These types of transfer imply that VSL can result in flexible representations, which may in turn allow VSL to function in ever-changing natural environments. Keywords: statistical learning, generalization, transfer, spatial layout, temporal order

Chicks were trained to discriminate small sets of identical elements. They were then tested for choices (unrewarded) between sets of similar numerosities, when continuous physical variables such as spatial distribution, contour length, and overall surface were equalized. In all conditions chicks discriminated one versus two and two versus three stimulus sets. Similar results were obtained when elements were presented under conditions of partial occlusion. In contrast, with sets of four versus five, four versus six, and three versus four elements chicks seemed unable to discriminate on the basis of number, although nonnumerical discrimination based on perceptual cues was observed. This adds to increasing evidence for discrimination of small numerosities of up to three elements in human infants and nonhuman animals. Keywords: number cognition, number discrimination, number sense, visual discrimination learning, domestic chick

Recent studies of visual statistical learning (VSL) have demonstrated that statistical regularities in sequences of visual stimuli can be automatically extracted, even without intent or awareness. Despite much work on this topic, however, several fundamental questions remain about the nature of VSL. In particular, previous experiments have not explored the underlying units over which VSL operates. In a sequence of colored shapes, for example, does VSL operate over each feature dimension independently, or over multidimensional objects in which color and shape are bound together? The studies reported here demonstrate that VSL can be both object-based and feature-based, in systematic ways based on how different feature dimensions covary. For example, when each shape covaried perfectly with a particular color, VSL was object-based: Observers expressed robust VSL for colored-shape sub-sequences at test but failed when the test items consisted of monochromatic shapes or color patches. When shape and color pairs were partially decoupled during learning, however, VSL operated over features: Observers expressed robust VSL when the feature dimensions were tested separately. These results suggest that VSL is object-based, but that sensitivity to feature correlations in multidimensional sequences (possibly another form of VSL) may in turn help define what counts as an object. Keywords: statistical learning, feature binding, objects, feature dimensions

Previous studies examining face learning have mostly used only a single exposure to 1 image of each of the faces to be learned. However, in daily life, faces are usually learned from multiple encounters. These 6 experiments examined the effects on face learning of repeated exposures to single or multiple images of a face. All experiments provided evidence for image-specific picture learning taking place over and above any invariant face learning, with recognition accuracy always highest for the image studied and performance falling across transformations between study and test images. The relative roles of pictorial and structural codes in mediating learning faces from photographs need to be reconsidered. Keywords: face learning, face recognition, pictorial and structural coding, single and multiple exposures

Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of 'cognitive' and 'perceptual' load. Keywords: inhibition, perceptual load, visual marking, motion

THE METACOGNITIVE performance of four groups of students was examined. The students' processes of visual analysis and discrimination of real-life pictures were used to measure metacognition. There were 61 participants: 18 hearing students, 18 deaf and hard of hearing students, 16 students with mild mental disabilities, and 9 students with physical disabilities. Analysis revealed no significant differences among hearing students, deaf and hard of hearing students, and students with physical disabilities. The performance of these three groups of students was significantly better than the performance of students with mild mental disabilities. It appears that students with mild mental disabilities encountered difficulties with pictures that required complex visual analyses and discriminations. These difficulties were manifested in a form of deficient simultaneous visual processing along with a low level of knowledge acquisition.

In conventional discrimination learning-set formation, it is possible that rhesus monkeys (Macaca mulatta) learn to lay down prospective memories by anticipating the next trial and deciding in advance what choice will be made. To test this hypothesis, the authors administered discrimination problems with 24-hr intertrial intervals, predicting that these long intervals would disrupt or prevent the putative anticipation of the next trial. Confirming their expectation, the authors found no indication of learning-set formation under these conditions. Keywords: macaque, visual learning, reward

Humans conduct visual search faster when the same display is presented for a 2nd time, showing implicit learning of repeated displays. This study examines whether learning of a spatial layout transfers to other layouts that are occupied by items of new shapes or colors. The authors show that spatial context learning is sometimes contingent on item identity. For example, when the training session included some trials with black items and other trials with white items, learning of the spatial layout became specific to the trained color--no transfer was seen when items were in a new color during testing. However, when the training session included only trials in black (or white), learning transferred to displays with a new color. Similar results held when items changed shapes after training. The authors conclude that implicit visual learning is sensitive to trial context and that spatial context learning can be identity contingent. Keywords: visual attention, visual search, implicit learning, spatial context learning

Attention and working memory limitations set strict limits on visual representations, yet researchers have little appreciation of how these limits constrain the acquisition of information in ongoing visually guided behavior. Subjects performed a brick sorting task in a virtual environment. A change was made to 1 of the features of the brick being held on about 10% of trials. Rates of change detection for feature changes were generally low and depended on the pick-up and put-down relevance of the feature to the sorting task. Subjects' sorting decision suggests that changes may be missed because of a failure to update the changed feature. The authors also explore how hand and eye behavior are coordinated for strategic acquisition and storage of visual information throughout the task. Keywords: change blindness, eye movements, task demand, visual working memory, visual attention

The perirhinal cortex was once thought to be 'silent cortex', virtually ignored by researchers interested in the neurobiology of learning and memory. Following studies of brain damage associated with cases of amnesia, perirhinal cortex is now widely regarded as part of a 'medial temporal lobe (MTL) memory system'. This system is thought to be more or less functionally homogeneous, having a special role in declarative memory, and making little or no contribution to other functions such as perception. In the present article, we summarize an alternative view. First, we propose that components of the putative MTL system such as the hippocampus and perirhinal cortex have distinct and dissociable functions. Second, we provide evidence that the perirhinal cortex has a role in visual discrimination. In addition, we propose a specific role for perirhinal cortex in visual discrimination: the contribution of complex conjunctive representations to the solution of visual discrimination problems with a high degree of 'feature ambiguity'. These proposals constitute a new view of perirhinal cortex function, one that does not assume strict modularity of function in the occipito-temporal visual stream, but replaces this idea with the notion of a hierarchical representational continuum.

A 'follow-the-dot' method was used to investigate the visual memory systems supporting accumulation of object information in natural scenes. Participants fixated a series of objects in each scene, following a dot cue from object to object. Memory for the visual form of a target object was then tested. Object memory was consistently superior for the two most recently fixated objects, a recency advantage indicating a visual short-term memory component to scene representation. In addition, objects examined earlier were remembered at rates well above chance, with no evidence of further forgetting when 10 objects intervened between target examination and test and only modest forgetting with 402 intervening objects. This robust prerecency performance indicates a visual long-term memory component to scene representation.

A sound presented in close temporal proximity to a visual stimulus can alter the perceived temporal dimensions of the visual stimulus (temporal ventriloquism). In this article, the authors demonstrate temporal ventriloquism in the flash-lag effect (FLE), a visual illusion in which a flash appears to lag relative to a moving object. In Experiment 1, the magnitude and the variability of the FLE were reduced, relative to a silent condition, when a noise burst was synchronized with the flash. In Experiment 2, the sound was presented before, at, or after the flash ([+ or -] ~100 ms), and the size of the FLE varied linearly with the delay of the sound. These findings demonstrate that an isolated sound can sharpen the temporal boundaries of a flash and attract its temporal occurrence.

A flashed stimulus is perceived as spatially lagging behind a moving stimulus when they are spatially aligned. When several elements are perceptually grouped into a unitary moving object, a flash presented at the leading edge of the moving stimulus suffers a larger spatial lag than a flash presented at the trailing edge (K. Watanabe, R. Nijhawan, B. Khurana, & S. Shimojo, 2001). By manipulation of the flash onset relative to the motion onset, the present study investigated the order of perceptual operations of visual motion grouping and relative visual localization. It was found that the asymmetric mislocalization was observed irrespective of physical and/or perceptual temporal order between the motion and flash onsets. Thus, grouping by motion must be completed to define the leading-trailing relation in a moving object before the visual system explicitly represents the relative positions of moving and flashed stimuli.

The relative efficacy with which appearance of a new object orients visual attention was investigated. At issue is whether the visual system treats onset as being of particular importance or only 1 of a number of stimulus events equally likely to summon attention. Using the 1-shot change detection paradigm, the authors compared detectability of new objects with changes occurring at already present objects--luminance change, color change, and object offset. Results showed that appearance of a new object was less susceptible to change blindness than changes that old objects could undergo. The authors also investigated whether it is onset per se that leads to enhanced detectability or onset of an object representation. Results showed that the onset advantage was eliminated for onsets that did not correspond with the appearance of a new object. These findings suggest that the visual system is particularly sensitive to the onset of a new object.

The Artificial Grammar Learning task has been used extensively to assess individuals' implicit learning capabilities. Previous work suggests that participants implicitly acquire rule-based knowledge as well as exemplar-specific knowledge in this task. This study investigated whether exemplar-specific knowledge acquired in this task is based on the visual features of the exemplars. When a change in the font and case occurred between study and test, there was no effect on sensitivity to grammatical rules in classification judgments. However, such a change did virtually eliminate sensitivity to training frequencies of letter bigrams and trigrams (chunk strength) in classification judgments. Performance of a secondary task during study eliminated this font sensitivity and generally reduced the contribution of chunk strength knowledge. The results are consistent with the idea that perceptual fluency makes a contribution to artificial grammar judgments.

What form is the lexical phonology that gives rise to phonological effects in visual lexical decision? The authors explored the hypothesis that beyond phonological contrasts the physical phonetic details of words are included. Three experiments using lexical decision and 1 using naming compared processing times for printed words (e.g., plead and pleat) that differ, when spoken, in vowel length and overall duration. Latencies were longer for long-vowel words than for shun-vowel words in lexical decision but not in naming. Further, lexical decision on long-vowel words benefited more from identity priming than lexical decision on short-vowel words, suggesting that representations of long-vowel words achieve activation thresholds more slowly. The discussion focused on phonetically informed phonologies, particularly gestural phonology and its potential for understanding reading acquisition and performance.

Abstract Both the events of September 11 and the media images now associated with that day underscore the importance of focusing on visual literacy in college writing courses. Students need [...]

Learning to use symbols is a challenge for young children even when the symbol in question (e.g., a live video image) is iconic and seems transparent to adults. This research examined the effect of experience on children's use of video-presented information. Two-year-old children saw themselves 'live' on their family television for 2 weeks and then participated in an object-retrieval task. The children reliably used a live video presentation of an adult hiding a toy in an adjoining room to find the toy. Most also transferred what they learned to a task involving another symbol (pictures) that typically is very difficult for this age group. The results reveal flexibility in 2-year-olds' symbol use that follows from successful representation of a symbolic relation.

This study investigated whether the factor of 'hypermedia preference' in a web-based learning environment (WBLE) affects students' task performance under 'learner control with and without advisement' conditions. Eighty-one undergraduates at [...]

Toddlers' ability to use cues such as eye gaze and gestures to infer the meaning of novel action words was examined. In Experiment 1, 21- and 27-month-olds were taught labels for pairs of videotaped actions that were either similar or dissimilar in appearance. Similar actions differed mainly in the presence of behavioral cues related to the agents' intentions (e.g., extended arms). Only the older children were able to learn the labels for the similar actions. In Experiment 2, 3 new pairs of labels (2 similar, 1 dissimilar) were taught to children in the same age range. Eye gaze and gestures were the main features distinguishing the similar events. The same developmental effect was observed, with only the older children showing learning of both types of verbs and the younger children being impeded by the appearance of the actions. The results show that by the middle of the 2nd year, children begin to consider intentions-in-action when acquiring the meaning of novel action verbs.

We studied the underlying neural mechanism of a simple choice behavior between competing alternatives in Drosophila. In a flight simulator, individual flies were conditioned to choose one of two flight paths in response to color and shape cues; after the training, they were tested with contradictory cues. Wild-type flies made a discrete choice that switched from one alternative to the other as the relative salience of color and shape cues gradually changed, but this ability was greatly diminished in mutant ([mbm.sup.1]) flies with miniature mushroom bodies or with hydroxyurea ablation of mushroom bodies. Thus, Drosophila genetics may be useful for elucidating the neural basis of choice behavior., Most animals can make a rapid and rational choice among alternative behaviors by assessing the advantages and disadvantages on the basis of previous experience, but the underlying neural mechanism is [...]

Middle-school and high-school students compete in a tournament with robots they make from Legos and processors at the Botball championships held in Austin, Texas, in 2000. It was founded by the technical director of the KISS Inst. for Practical Robotics. He says Botball is a good way to get young people interested in robotics and programming and sometimes to get them to stay in school. Other regional tournaments are encouraged.

Visual learning is discussed by Michigan State University staff members using navigation as an example. A state-based learning method is presented.

Gesture is widely regarded to play an important role in communication, both in conjunction with and independent of speech. Indeed, gesture is known to develop even before the onset of spoken words. However, little is known about the communicative conditions under which gesture emerges. The aim of this study was to explore the role of vision in early gesturing. We examined gesture development in 5 congenitally blind and 5 sighted toddlers videotaped longitudinally between the ages of 14 and 28 months in their homes while engaging in free play with a parent or experimenter. All of the blind children were found to produce at least some gestures during the one-word stage of language development. However, gesture production was relatively low among the blind children relative to their sighted peers. Moreover, although blind and sighted children produced the same overall set of gesture types, the distribution of gesture types across categories differed, in addition, blind children used gestures primarily to communicate about objects that were nearby, while sighted children used them for nearby as well as distally located objects. These findings suggest that gesture may play different roles in the language-learning process for sighted and blind children. Nevertheless, they also make it clear that gesture is a robust phenomenon of early communicative development, emerging even in the absence of experience with a visual model.

Visual learning in the fly Drosophila melanogaster was studied using a flight simulator. Memory retrieval was found to be partly context-independent. the facilitating effect of context cues for memory retrieval appears to be the default state, while making recall context-independent needs further processing.

We investigated plane rotation effects on the minimum presentation duration that is required in order to recognize pictures of familiar objects, using the method of ascending limits. Subjects made unspeeded verification responses, selecting from 126 written alternatives. Replicating similar identification studies in which brief, masked pictures (Lawson & Jolicoeur, 1998) were presented, disorientation reduced the efficiency of recognition. Mirroring the findings in speeded picture naming studies (e.g., Jolicoeur, 1985; Jolicoeur & Milliken, 1989), but in contrast to those of Lawson and Jolicoeur (1998), orientation effects were found over a wide range of views and were attenuated but not eliminated with experience with a given object. The results bridge the findings from unspeeded verification and speeded naming tasks. They suggest that the same orientation-sensitive processes are tapped in both cases, and that practice effects on these processes are object specific.

The visual environment is extremely rich and complex, producing information overload for the visual system. But the environment also embodies structure in the form of redundancies and regularities that may serve to reduce complexity. How do perceivers internalize this complex informational structure? We present new evidence of visual learning that illustrates how observers learn how objects and events covary in the visual world. This information serves to guide visual processes such as object recognition and search. Our first experiment demonstrates that search and object recognition are facilitated by learned associations (covariation) between novel visual shapes. Our second experiment shows that regularities in dynamic visual environments can also be learned to guide search behavior. In both experiments, learning occurred incidentally and the memory representations were implicit. These experiments show how top-down visual knowledge, acquired through implicit learning, constrains what to expect and guides where to attend and look.

We previously reported that chimpanzees were unable to optimally select the smaller of two candy arrays in order to receive a larger reward. When Arabic numerals were substituted for the candy arrays, animals who had had prior training with numerical symbols showed an immediate and significant improvement in performance and were able to select reliably the smaller numeric representation in order to obtain a larger reward. Poor performance with candy arrays was interpreted as reflecting a response bias toward the intrinsic incentive and/or perceptual features of the larger array. In contrast, the Arabic numerals represent numerosity symbolically and appear to promote response choice on the basis of abstract processing of numerosity, with minimal interference from the inherent properties of the choice stimuli. The present study tested the hypothesis that, for mixed symbol-candy choice pairs, the requisite processing of the abstract numeral may foster a mode of numerical judgment that diminishes the interfering incentive/perceptual effects of the candy stimuli. The results were consistent with this hypothesis. Whereas performance on candy-candy arrays was significantly below chance levels, performance on numeral-candy choice pairs was significantly above chance and comparable with performance on numeral-numeral pairs.

These experiments examined one way in which the allocation of attentional resources can change performance during a visual discrimination task. Pigeons were trained to discriminate visual forms under conditions that produced dimensional contrast. In three experiments, negative training stimuli differed from positive stimuli either along a primary physical dimension alone or along both a primary dimension and an orthogonal dimension. When a negative stimulus differed from positive stimuli along two dimensions, discrimination of that negative stimulus improved. For one type of visual form, discrimination of the positive stimuli declined with orthogonal variation in a negative stimulus, whereas for other visual forms, there was no decline in performance. These results are consistent with a model of dimensional contrast that suggests that differences in the allocation of attentional resources determine discrimination performance. The results also indicate that the organization of stimulus dimensions plays a crucial role in the allocation of attentional resources in these settings.

Recent research supports a significant role for prenatal sensory experience in the development of lateralized postnatal visual discrimination in birds, but little is known about its potential effect on the development of lateralized postnatal motor behaviors. Therefore, the present study examined the effects of prenatal visual experience on the development of spatial turning bias in domestic chicks. Control tests with maternally naive, domestic chicks in a standard T maze revealed a left-side turning bias in 90% of subjects. Such large population biases are considered unusual in nonhuman species. Chicks were exposed to one of three prenatal conditions: both eye systems exposed to enhanced visual experience, right-eye system exposed/left-eye system occluded, or left-eye system exposed/right-eye system occluded. Results revealed a significant lack of population turning bias in all experimental subjects except those that received right eye stimulation prenatally. These results suggest that unilateral prenatal visual experience to the right eye/left hemisphere is a significant contributor to the lateralization process in domestic chicks., It has long been recognized that the avian brain is structurally and functionally lateralized (Bradshaw & Rogers, 1993). Additionally, the avian nervous system has anatomical and developmental features that make [...]