Tactual, visual, and cross-modal transfer of texture in 5- and 8-year-old children

Children's tactual, visual, and cross-modal transfer abilities for texture were investigated in a delayed matching-to-sample paradigm. Transfer performance from vision to touch was found to increase between 5 and 8 years of age, whereas transfer performance from touch to vision did not vary with age and matched touch-to-touch performance. Asymmetrical cross-modal abilities were observed at the age of 8 years, vision-to-touch transfer performance being higher than touch-to-vision transfer performance (experiment 2). This developmental pattern could not be attributed to limitations in the tactual or visual discriminability of the textures or to differences in tactual or visual memory between the two age groups (experiment 1). It is suggested that the increase with age in vision-to-touch performance may be related to the intervention of more efficient top-down perceptual processes in the older children.     

Perceptual visual skills in young highly skilled basketball players

A simple method was designed to evaluate visual abilities such as disance visual acuity, binocular horizontal visual field, simple and choice visual reaction times, and stereoscopic vision in skilled 11- to 13-yr.-old basketball players participating in a 15-day summer training camp. On a test battery, visual abilities were monitored in 473 players of the Spanish Basketball Federation over a 5-yr. period. The players showed outstanding scores on distance visual acuity and stereoscopic vision, and good visual reaction times and horizontal visual fields. When scores were compared by sex and age, significant differences on certain visual measures were observed. Many layers showed crossed eye-hand dominance. Visual screening programs may help promote visual health among junior basketball players and could be used for performance training.     

Movement segmentation and visual perturbation increase developmental differences in motor control and learning

We examined the developmental differences in motor control and learning of a two‐segment movement. One hundred and five participants (53 female) were divided into three age groups (7–8 years, 9–10 years and 19–27 years). They performed a two‐segment movement task in four conditions (full vision, fully disturbed vision, disturbed vision in the first movement segment and disturbed vision in the second movement segment). The results for movement accuracy and overall movement time show that children, especially younger children, are more susceptible to visual perturbations than adults. The adults’ movement time in one of the movement segments could be increased by disturbing the vision of the other movement segment. The children's movement time for the second movement segment increased when their vision of the first movement segment was disturbed. Disturbing the vision of the first movement segment decreased the percentage of central control of the second movement in younger children, but not in the other two age groups. The children's normalized jerk was more easily increased by visual perturbations. The children showed greater improvement after practice in the conditions of partial vision disturbance. As the participants’ age increased, practice tended to improve their feedforward motor control rather than their feedback motor control. These results suggest that children's central movement control improves with age and practice. We discuss the theoretical implications and practical significance of the differential effects of visual perturbation and movement segmentation upon motor control and learning from a developmental viewpoint.     

Late maturation of visual hyperacuity

We used a visual evoked–potential measure to study the development of two components of pattern vision, vernier acuity and grating acuity, in humans from early infancy through adolescence. These two visual functions develop at similar rates and have nearly the same absolute values between 1 month and 6 years of age. After age 6, grating acuity is constant at the adult level, but vernier acuity continues to improve, becoming a hyperacuity. Vernier acuity reaches asymptotic levels around age 14 years. These results suggest that adultlike vernier hyperacuity is not limited by spatial resolution or sensitivity of small receptive fields, but rather that the limitation is imposed by higher–level processing. Sensitivity, connections in visual cortical areas, or both therefore retain plasticity throughout childhood and into adolescence.     

Visual size perception and haptic calibration during development

It is still unclear how the visual system perceives accurately the size of objects at different distances. One suggestion, dating back to Berkeley’s famous essay, is that vision is calibrated by touch. If so, we may expect different mechanisms involved for near, reachable distances and far, unreachable distances. To study how the haptic system calibrates vision we measured size constancy in children (from 6 to 16 years of age) and adults, at various distances. At all ages, accuracy of the visual size perception changes with distance, and is almost veridical inside the haptic workspace, in agreement with the idea that the haptic system acts to calibrate visual size perception. Outside this space, systematic errors occurred, which varied with age. Adults tended to overestimate visual size of distant objects (over‐compensation for distance), while children younger than 14 underestimated their size (under‐compensation). At 16 years of age there seemed to be a transition point, with veridical perception of distant objects. When young subjects were allowed to touch the object inside the haptic workspace, the visual biases disappeared, while older subjects showed multisensory integration. All results are consistent with the idea that the haptic system can be used to calibrate visual size perception during development, more effectively within than outside the haptic workspace, and that the calibration mechanisms are different in children than in adults.     

Development of a vocabulary of object shapes in a child with a very-early-acquired visual agnosia: A unique case

We report a longitudinal study of an exceptional child (S.R.) whose early-acquired visual agnosia, following encephalitis at 8 weeks of age, did not prevent her from learning to construct an increasing vocabulary of visual object forms (drawn from different categories), albeit slowly. S.R. had problems perceiving subtle differences in shape; she was unable to segment local letters within global displays; and she would bring complex scenes close to her eyes: a symptom suggestive of an attempt to reduce visual crowding. Investigations revealed a robust ability to use the gestalt grouping factors of proximity and collinearity to detect fragmented forms in noisy backgrounds, compared with a very weak ability to segment fragmented forms on the basis of contrasts of shape. When contrasts in spatial grouping and shape were pitted against each other, shape made little contribution, consistent with problems in perceiving complex scenes, but when shape contrast was varied, and spatial grouping was held constant, S.R. showed the same hierarchy of difficulty as the controls, although her responses were slowed. This is the first report of a child's visual–perceptual development following very early neurological impairments to the visual cortex. Her ability to learn to perceive visual shape following damage at a rudimentary stage of perceptual development contrasts starkly with the loss of such ability in childhood cases of acquired visual agnosia that follow damage to the established perceptual system. Clearly, there is a critical period during which neurological damage to the highly active, early developing visual–perceptual system does not prevent but only impairs further learning.     

Reduced visual acuity is mirrored in low vision imagery

Research has examined the nature of visual imagery in normally sighted and blind subjects, but not in those with low vision. Findings with normally sighted subjects suggest that imagery involves primary visual areas of the brain. Since the plasticity of visual cortex appears to be limited in adulthood, we might expect imagery of those with adult-onset low vision to be relatively unaffected by these losses. But if visual imagery is based on recent and current experience, we would expect images of those with low vision to share some properties of impaired visual perception. We examined key parameters of mental images reported by normally sighted subjects, compared to those with early- and late-onset low vision, and with a group of subjects with restricted visual fields using an imagery questionnaire. We found evidence that those with reduced visual acuity report the imagery distances of objects to be closer than those with normal acuity and also depict objects in imagery with lower resolution than those with normal visual acuity. We also found that all low vision groups, like the normally sighted, image objects at a substantially greater distance than when asked to place them at a distance that ‘just fits’ their imagery field (overflow distance). All low vision groups, like the normally sighted, showed evidence of a limited visual field for imagery, but our group with restricted visual fields did not differ from the other groups in this respect. We conclude that imagery of those with low vision is similar to that of those with normal vision in being dependent on the size of objects or features being imaged, but that it also reflects their reduced visual acuity. We found no evidence for a dependence on imagery of age of onset or number of years of vision impairment.     

Late‐ but not early‐onset blindness impairs the development of audio‐haptic multisensory integration

Integrating different senses to reduce sensory uncertainty and increase perceptual precision can have an important compensatory function for individuals with visual impairment and blindness. However, how visual impairment and blindness impact the development of optimal multisensory integration in the remaining senses is currently unknown. Here we first examined how audio‐haptic integration develops and changes across the life span in 92 sighted (blindfolded) individuals between 7 and 70 years of age. We used a child‐friendly task in which participants had to discriminate different object sizes by touching them and/or listening to them. We assessed whether audio‐haptic performance resulted in a reduction of perceptual uncertainty compared to auditory‐only and haptic‐only performance as predicted by maximum‐likelihood estimation model. We then compared how this ability develops in 28 children and adults with different levels of visual experience, focussing on low‐vision individuals and blind individuals that lost their sight at different ages during development. Our results show that in sighted individuals, adult‐like audio‐haptic integration develops around 13–15 years of age, and remains stable until late adulthood. While early‐blind individuals, even at the youngest ages, integrate audio‐haptic information in an optimal fashion, late‐blind individuals do not. Optimal integration in low‐vision individuals follows a similar developmental trajectory as that of sighted individuals. These findings demonstrate that visual experience is not necessary for optimal audio‐haptic integration to emerge, but that consistency of sensory information across development is key for the functional outcome of optimal multisensory integration.     

Sensitivity to triadic attention in early infancy

In Study 1, 54 3-, 6- and 9-month-old infants interacted with an adult stranger who engaged in a face-to-face (dyadic) exchange. Dyadic interaction was halted when the adult turned away to look at an object. In a Joint Attention condition, the adult alternated visual attention between the infant and the object, and in a Look Away condition she looked away at the object only. Infants gazed and smiled more in the Joint Attention condition compared to in the Look Away condition. Infants' gazing to the target object interacted with age and condition. In Study 2, 37 3-, 6- and 9-month old infants interacted with an adult who coordinated visual attention and affect, affect only, visual attention only, or ignored the infant. Infants gazed reliably more at E when she coordinated both affect and attention and smiled reliably more when the adult coordinated affect and attention or attention only. The findings show a sensitivity to triadic attention by 3 months of age.     

Peripheral vision and back tuck somersaults.

Although vision appears to enhance performance of somersaulting skills, few studies have investigated the source (foveal or ambient) of useful visual cues that can potentially be used by gymnasts during a somersault. Therefore, the primary objectives were to investigate the possible role of peripheral vision in the control of orientation and landing balance in a back tuck somersault. 10 female gymnasts (age = 11.6 +/- 2.7 yr., competitive level = 8 +/- 1.2, training time in gymnastics = 5.9 +/- 1.6 yr.) performed back tuck somersaults under four visual conditions (full visual field, horizontal peripheral vision limited to 100 degrees, horizonal peripheral vision limited to 60 degrees, and no vision) while wearing electromagnetic sensors that allowed automatic digitizing. Analysis yielded no statistically significant difference on any of the kinematic variables among vision conditions. Despite limiting the gymnasts' available horizontal peripheral vision, joint angles, angular velocities, and timing remained very similar. There were no statistically significant differences in landing balance between the conditions of full vision, 100 degrees peripheral vision, and 60 peripheral vision. However, gymnasts were less stable at landing when vision was absent as compared to the three other vision conditions.     

Vision and intelligence at age 83 in the Lothian Birth Cohort 1921

The extent to which visual function, measured as near and distant visual acuity and contrast sensitivity, is correlated with concurrently measured cognitive function and prior intellectual ability was investigated in a narrow age range group known as the Lothian Birth Cohort of 1921 (LBC1921). Participants were aged ~ 83 years at the time of testing (N = 321). A well-fitting structural equation model highlighted a significant contribution of a latent visual trait to a general fluid intelligence factor in old age, independent of the contribution from childhood intelligence. Additionally, childhood intelligence made a significant contribution to the general visual factor in old age. However, the model fitted equally well when the fluid intelligence factor is assumed to be a cause of the visual function latent trait, in which case childhood intelligence does not significantly influence vision in old age. We discuss these results with respect to four possible mechanisms by which vision and cognition can come to be correlated over the lifecourse.     

汉语发展性阅读障碍儿童视觉注意广度的发展及其对阅读流畅性的作用

以85名小学2~6年级儿童为研究对象,采用方差分析、分层回归探讨小学高、低年龄阶段发展性阅读障碍儿童视觉注意广度的发展变化,并以同年龄正常阅读者作为对照组;同时在不同年龄阶段探究视觉注意广度对阅读流畅性发展的预测作用。结果显示：（1）发展性阅读障碍儿童存在视觉注意广度缺陷,并呈现出在小学高年龄阶段更严重的趋势;（2）在阅读障碍儿童中,视觉注意广度对汉语流畅阅读的显著预测作用随发展增强;而对于正常阅读者,视觉注意广度仅显著预测低年龄段学生的句子朗读流畅阅读能力。以上结果表明视觉注意广度与汉语流畅阅读能力关系密切,今后汉语阅读障碍的相关干预研究可以尝试从视觉注意广度训练方面切入。     

Visual/cognitive correlates of vehicle accidents in older drivers

Older drivers have more accidents per miles driven than any other age group and tend to have significant impairments in their visual function, which could interfere with driving. Previous research has largely failed to document a link between vision and driving in the elderly. We have taken a comprehensive approach by examining how accident frequency in older drivers relates to the visual/cognitive system at a number of levels: ophthalmological disease, visual function, visual attention, and cognitive function. The best predictor of accident frequency as recorded by the state was a model incorporating measures of early visual attention and mental status, which together accounted for 20% of the variance, a much stronger model than in earlier studies. Those older drivers with a visual attentional disorder or with poor scores on a mental status test had 3-4 times more accidents (of any type) and 15 times more intersection accidents than those without these problems.     

36‐month‐olds conceal visual and auditory information from others

By three years of age, children are skilled at assessing under which circumstances others can see things. However, nothing is known about whether they can use this knowledge to guide their own deceptive behaviour. Here we investigated 3‐year‐olds’ ability to strategically inhibit or conceal forbidden actions that a nearby adult experimenter could see or hear. In the first experiment, children were more likely to disobey the adult when she did not have visual access to their activities than they were when she was looking at them. In the second experiment, in which the adult could never see the child, children refrained from making noise when engaging in a prohibited action that the adult might hear. These results suggest that by three years of age children use their knowledge of others’ perceptual states to decide whether it is safe to commit a transgression and, moreover, actively conceal perceptual cues that could reveal to others their ongoing transgression.     

Porterfield and Wells on the motions of our eyes

William Porterfield (ca 1969-1771) and William Charles Wells (1757-1817) conducted experimental investigations on eye movements related to accommodation, binocular vision, and vertigo. Porterfield gave a correct interpretation of Scheiner's experiment and invented an optometer to measure the near and far points of distinct vision. He also demonstrated the involvement of the crystalline lens in accommodation by examining vision in an aphakic person. Wells devised an alternative means of measuring the limits of vision and noted his own deterioration of sight with age; he studied the effects of belladonna on pupil size and accommodation. Their analyses of binocular visual direction contrasted Porterfield's view that perceived location was innately determined with Well's argument that visual direction was innate whereas visual distance was learned. Both Porterfield and Wells investigated the involvement of eye movements in binocular vision and in postrotary visual motion. Porterfield maintained that the eyes did not move following body rotation, whereas Wells, using an afterimage as stabilised retinal image, described the characteristics of postrotary nystagmus and their dependence on head orientation. Despite the neglect of Well's work, he should be considered as laying the foundations for the study of vestibular-visual interaction, even though the function of the vestibular system was not known at that time.     

Location coding by the human visual system: multiple topological adaptations in a case of strabismic amblyopia

Amblyopia, a major cause of vision loss, is a developmental disorder of visual perception commonly associated with strabismus (squint). Although defined by a reduction in visual acuity, severe distortions of perceived visual location are common in strabismic amblyopia. These distortions can help us understand the cortical coding of visual location and its development in normal vision, as well as in amblyopia. The history of retinotopic mapping in the visual cortex highlights the potential impact of amblyopia. Theories of amblyopia include topological disarray of receptors in primary visual cortex, undersampling from the amblyopic eye compared with normal eyes, and the presence of anomalous retinal correspondence or multiple cortical representations of the strabismic fovea. We examined the distortions in a strabismic amblyope, using a pop-out localization task, in which normal observers made errors dependent on the visual context of the stimulus. The localization errors of the strabismic amblyope were abnormal. We found that none of the available theories could fully explain this one patient's localization performance. Instead, the observed behavior suggests that multiple adaptations of the underlying cortical topology are possible simultaneously in different parts of the visual field.     

Thinking Developmentally: Perspectives Following Loewald and Klein

In this article, I explore two perspectives on development that are central to how I think and work as an analyst, one drawn from the work of Hans Loewald and one from Melanie Klein. Loewald turned the usual psychoanalytic way of thinking, rooted in the past, on its head when he theorized that development proceeds by internalization of the parent’s future vision of the child and, by corollary, the analyst’s future vision of the patient. Using a vignette from Klein’s work with 10-year-old Richard, I show how the analyst’s image of the patient’s potential can facilitate growth and development. Melanie Klein also introduced a radical reordering of traditional psychoanalytic theory when she theorized that the mind develops and is structured as positions, not as successive phases. For Klein, the mind is organized in groupings of anxieties, defenses, and object-relations that are in a continuous state of oscillation throughout life independent of chronological age. Through a clinical vignette, I illustrate how one understands a patient differently when development is seen as occuring in momentary shifts between different levels of the personality rather than as stages over time.     

Cognition as the Cooperative Appropriation of Affordances

Michaels (2000) expressed concerns about the implications of the notion of 2 visual systems (Milner &; Goodale, 1995) for ecological psychology. This leads her to suggest a decoupling of perception and action, by which action is separate from perception. It is suggested that although Michaels noted, on the one hand, that Milner and Goodale's approach to perception is a constructivist one, she mistakenly adopts their view that separates vision for perception from vision for action. An alternative position is presented, based on a recent article (Norman, in press), in which the parallels between the 2 visual systems, dorsal and ventral, and the 2 theoretical approaches, ecological and constructivist, are elucidated. According to this dual-process approach to perception, both systems are perceptual systems. The ecological-dorsal system is the system that picks up information about the ambient environment allowing the organism to negotiate it. It is suggested that this type of perception always processes the relevant information for action and that there is no need to sever the perception-action coupling. Ecological psychology and the 2 visual systems are quite compatible, and there is no need for concern.     

Short-term memory for spatial configurations in the tactile modality: A comparison with vision

This study investigates the role of acquisition constraints on the short-term retention of spatial configurations in the tactile modality in comparison with vision. It tests whether the sequential processing of information inherent to the tactile modality could account for limitation in short-term memory span for tactual-spatial information. In addition, this study investigates developmental aspects of short-term memory for tactual- and visual-spatial configurations. A total of 144 child and adult participants were assessed for their memory span in three different conditions: tactual, visual, and visual with a limited field of view. The results showed lower tactual-spatial memory span than visual-spatial, regardless of age. However, differences in memory span observed between the tactile and visual modalities vanished when the visual processing of information occurred within a limited field. These results provide evidence for an impact of acquisition constraints on the retention of spatial information in the tactile modality in both childhood and adulthood.