The suggestion that the body surface might be used as an additional means of presenting information to human-machine operators has been around in the literature for nearly 50 years. Although recent technological advances have made the possibility of using the body as a receptive surface much more realistic, the fundamental limitations on the human information processing of tactile stimuli presented across the body surface are, however, still largely unknown. This literature review provides an overview of studies that have attempted to use vibrotactile interfaces to convey information to human operators. The importance of investigating any possible central cognitive limitations (i.e., rather than the peripheral limitations, such as related to sensory masking, that were typically addressed in earlier research) on tactile processing for the most effective design of body interfaces is highlighted. The applicability of the constraints emerging from studies of tactile processing under conditions of unisensory (i.e., purely tactile) stimulus presentation, to more ecologically valid conditions of multisensory stimulation, is also discussed. Finally, the results obtained from recent studies of tactile information processing under conditions of multisensory stimulation are described, and their implications for haptic/tactile interface design elucidated.

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Experiments on scene perception and change blindness suggest that the visual system does not construct detailed internal models of a scene. These experiments therefore call into doubt the traditional view that vision is a process in which detailed representations of the environment must be constructed. The non-existence of such detailed representations, however, does not entail that we do not perceive the detailed environment. The “grand illusion hypothesis ” that our visual world is an illusion rests on (1) a problematic “reconstructionist” conception of vision, and (2) a misconception about the character of perceptual experience.

Eye movements were monitored while participants performed a change detection task with images of natural scenes. An initial and a modified scene image were displayed in alternation, separated by a blank interval (flicker paradigm). In the modified image, a single target object was changed either by deleting that object from the scene or by rotating that object 90º in depth. In Experiment 1, fixation position at detection was more likely to be in the target object region than in any other region of the scene. In Experiment 2, participants detected scene changes more accurately, with fewer false alarms, and more quickly when allowed to move their eyes in the scene than when required to maintain central fixation. These data suggest a major role for fixation position in the detection of changes to natural scenes across discrete views. When we view natural scenes, our impression is that the mind constructs something like an internal photographic image of the entire field of view. However, investigations of visual short-term memory (VSTM) across saccadic eye movements suggest that the visual information retained from one eye fixation to the next is abstracted away from low-level sensory stimulation and that VSTM preserves information from only a small portion of the visual

The ability of animals to select a limited region of sensory space for scrutinyisanimportant factor in dealing with cluttered or complex sensory environments. Such an #attentional" system in the visual domain is believed to be involved in both the perception of objects and the control of eyemovements in primates. While wecanintentionally guide our attention to perform a speci#c task, it is also re#exively drawn to #salient" features in our sensory input space. Understanding how high-level task information and low-level stimulus information can combine to control our sensory processing is of great interest to both neuroscience and engineering. Towards this end, wehave designed and fabricated a one-dimensional, analog VLSI vision chip that models covert attentional search and tracking. We extend previous analog VLSI work #Morris and DeWeerth, 1997# on delayed inhibition in a winner-take-all network to use extracted image edges as input to the attentional saliency map and to perform serial search on a particular feature conjunction #spatial derivative and direction-of-motion#. We further demonstrate the abilitytomodifythe circuit's parameters #on-the-#y" to switchbetween a search mode and a tracking mode.

It is well documented that the ability to effectively scan a visual scene is modulated by the perceptual and cognitive demands of the observer’s search task, with increases in visual workload effecting changes to both overt attention, the eye movements made in searching

This paper reviews research examining the role of visual memory in scene perception and visual search. Recent theories in these literatures have held that coherent object representations in visual memory are fleeting, disintegrating upon the withdrawal of attention from an object. I discuss evidence demonstrating that, far from being transient, visual memory supports the accumulation of information from scores of individual objects in scenes, utilizing both visual short-term memory and visual long-term memory. In addition, I review evidence that memory for the spatial layout of a scene and memory for specific object positions can efficiently guide search within natural scenes. In the past decade, the interaction between perception and memory has received a great deal of attention from cognitive scientists. Much of this interest has originated from increased understanding that perception is a dynamic, serial process, extended over space and time. In this paper, I will discuss two related lines of research in which the relationship between perception and memory has come to the fore: Scene perception and visual

This paper investigates a new species of skeptical reasoning about visual experience that takes its start from developments in perceptual science (especially recent work on change blindness and inattentional blindness). According to this skepticism, the impression of visual awareness of the environment in full detail and high resolution is illusory. I argue that the new skepticism depends on misguided assumptions about the character of perceptual experience, about whether perceptual experiences are ‘internal’ states, and about how best to understand the relationship between a person’s or animal’s perceptual capacities and the brain-level or neural processes on which they depend. I propose a conception of perceptual experience as a form of skillful engagement with the environment on the part of the whole person or animal.

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.

Large changes in a scene often become difficult to notice if made during an eye movement, image flicker, movie cut, or other such disturbance. It is argued here that this change blindness can serve as a useful tool to explore various aspects of vision. This argument centers around the proposal that focused attention is needed for the explicit perception of change. Given this, the study of change perception can provide a useful way to determine the nature of visual attention, and to cast new light on the way that it is — and is not — involved in visual perception. To illustrate the power of this approach, this paper surveys its use in exploring three different aspects of vision. The first concerns the general nature of seeing. To explain why change blindness can be easily induced in experiments but apparently not in everyday life, it is proposed that perception involves a �irtual representation, where object representations do not accumulate, but are formed as needed. An architecture containing both attentional and nonattentional streams is proposed as a way to implement this scheme. The second aspect concerns the ability of observers to detect change even when they have no visual experience of it. This sensing is found to take on at least two forms: detection without visual experience (but still with conscious awareness), and detection without any awareness at all. It is proposed that these are both due to the operation of a nonattentional visual stream. The final aspect considered is the nature of visual attention itself — the mechanisms involved when scrutinizing items. Experiments using controlled stimuli show the existence of various limits on visual search for change. It is shown that these limits provide a powerful means to map out the attentional mechanisms involved. © 2000