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Web Posted on: December 31, 1998


VIRTUAL REALITY USE IN REMEDIATING CHILDREN'S SPATIAL DEFICITS

N. Foreman
Leicester University, UK

P. Wilson
Leicester University, UK

D. Stanton
now Nottingham University, UK

e-mail: for@le.ac.uk

Introduction: VR and Psychology

Spatial perception was one of the earliest realms of behaviour to be investigated by psychologists, and one of the earliest PhD theses in psychology in the US was obtained by G Stanley Hall in 1878, working in this area. For psychologists, spatial perception has a significance beyond simply reaching toward cues or correctly detecting the locus of a stimulus; all behaviour can be said to occur in spatial contexts, and thus the term "spatial" can be applied to reaching and visual-spatial orientation at one end of the scale, but to navigation through buildings and cities at the other (Foreman and Gillett, 1997).

In the past, experimental psychologists have made good use of computer technology, to improve the quality and flexibility of stimulus displays. In a sense, when Virtual Reality (VR) emerged as an affordable medium, its adoption by psychologists represented a further step in this direction. However VR technology promised new opportunities; with VR it is theoretically possible to substitute the sensory environment with a computer generated world, in which the 3-D stimulus array is flexible and controllable, the viewer can interact with objects, and in which behaviour can be precisely monitored. Participants behave, at least in some respects, as though present in the virtual world. It is hardly surprising that this medium has attracted so much interest from psychologists, since it enables the examination of phenomena that would be difficult or impossible to test in the real world.

Moreover, since interactivity can be tailored to the abilities of the individual user, VR may prove particularly useful for individuals whose interaction with the real world is limited in some way. Numerous studies have begun to investigate the potential of VR, examining the importance of interaction per se in the acquisition of spatial skills and knowledge, and transfer between real and virtual conditions in able-bodied and disabled participants (see a special edition of the Communications of the ACM, volume 40 [8], 1997). Our own work has addressed a particular niche: how might VR experience benefit spatial navigational skills in individuals with impaired mobility?


Past Research in Leicester, UK

A number of years ago, it was shown that children with special needs, whose independent movement in space is restricted, had difficulty making accurate spatial judgments. For example, when asked to point from their school desk to landmarks on the school campus (landmarks currently out of view), they did so with less accuracy than a matched control group of able bodied peers (Foreman et al, 1989). Not all of the disabled children in that study had sustained brain injury; some suffered from peripheral conditions, suggesting that rather than spatial awareness having been compromised by damage to spatial neural structures per se, children's spatial skills may be curtailed for functional reasons, probably due to their relatively impoverished environmental experience. Exploration, error correction, or other experiences which promote the acquisition of spatial knowledge in able bodied children had been absent from most of their daily lives. We believed that VR holds a solution to this problem: in a virtual world, the only mobility required is that which controls an input device. Such children could experience free choice and self-initiated displacements in VR, perhaps for the first time.

However, we were sceptical that virtual experience might be inadequate to convey the kind of information that an individual uses to construct the map-like cognitive representations which are arguably necessary for successful navigation in large scale spaces. VR is limited insofar as environments displayed on computer monitors are far from true reality; first, they are typically rather bland, lacking real world clutter and detail. Second, interaction with a virtual world is artificial; indeed, controlling an input device such as a joystick or mouse might occupy some cognitive capacity and compete with spatial task demands. Third, virtual movement does not result in "reafferent" feedback (from head and body receptors) that is normally contingent on real-world movement.

In early studies, virtual versions of the psychology building in Leicester University, UK were constructed and disabled children were invited to make virtual tours, identifying the locations of items of fire equipment. Somewhat to our surprise, they were subsequently able to take the experimenters around the building, demonstrating substantial knowledge about its spatial layout. In particular, when these participants were asked to make pointing judgments to fire equipment sites within the building, they could do so with great accuracy, and considerably better than guessing controls. These preliminary data were followed up via a larger study, financed by BT (the UK telecommunications company) via the UK disability charity, Action Research. In this project we carried out a succession of experimental tasks (involving test environments having no real-world counterpart), which again showed that disabled children were able to gain spatial knowledge from virtual displays, though in one study, their ability to do so was dependent upon their mobility history: in a kite-shaped maze that required spatial inferences for the adoption of novel routes, those children who had experienced early mobility (losing mobility later in childhood) outperformed those whose mobility had improved across childhood from a low base. It would appear that the bases of spatial cognitive skill are established at particular stages in early childhood, and that these are not so easily acquired at later stages.

In the course of these studies we also carried out transfer tests to determine the extent of transfer between VR and the real world. In one study in particular, some mobility-restricted children of around 7-11 years in a special school in Derbyshire, UK were given a series of exploratory sessions, lasting one hour on each of 5 successive days, in which they toured the campus of another special school in a distant town (Leicester). They were trained to make pointing judgments toward out-of-sight landmarks, and given spatial training in using shortest routes between rooms. When tested in the actual Leicester school, their spatial knowledge of the school was considerably better than guessing controls. In a further set of studies, we found that the more time children spent in virtual environments, the better was their ability to perform such tasks; in other words, virtual experience was not simply providing them with knowledge of a particular experienced environment, but seemed to be compensating for previously lost experience, inasmuch as their ability to encode (at least virtual) spatial environments improved with training. Although we have not yet tested the hypothesis directly, we would expect that following such training, an individual would be better able to spatially encode new environments in the real world. We would like to think that when exposed to VR, these children began to think spatially, perhaps to begin to pay greater attention to spatial cues, and take control of their spatial exploration in a way that they had not done hitherto (see Foreman & Wilson., 1995; Foreman et al, 1997; Stanton et al, 1996; Wilson et al, 1997a,b).


Continuing Research

Given the restriction of the visual field in VR helmets and on screens, it is extremely unlikely that VR spatial experience can be regarded as the equivalent of normal exploration in all respects. Thus, despite the accumulating reports of effective acquisition that have been published in recent years, work is needed to assess the importance of visual field extent, interactivity, and presentation mode in order to maximise the benefits of the technology. We are currently funded by BT via the UK charity SCOPE to study the uses of VR in acquiring 3-D representations of complex buildings such as shopping malls. This is important for children with restricted mobility who are learning about space, and also for senior citizens who might better retain their spatial skills via VR training, and thus enjoy a more inclusive lifestyle by acquiring confidence in public places. Among the benefits of using VR in such contexts is the possibility of highlighting and sign-posting in early stages of training, gradually fading or withdrawing these props as performance improves. Work in Leicester is currently addressing the use of VR in Neuropsychology, for assessing spatial dysfunction in Parkinsons Disease and in head-injured adults and children.


References

Foreman, N. P., Orencas, C., Nicholas, E., Morton, P. & Gell, M. Spatial awareness in seven to eleven year-old physically handicapped children in mainstream schools. European Journal of Special Needs Education, 1989, 4, 171-179.

Foreman, N., & Wilson, P. Prospects for Virtual Reality computing in paediatric medicine. Ambulatory Child Health, 1995, 1, 176-182.

Foreman, N., Wilson, P., & Stanton, D. VR and spatial awareness in disabled children. Communications of the ACM (Association for Computing), 1997, 40, 76-77.

Foreman, N. P., & Gillett, R. (Eds.), Handbook of Spatial Research Paradigms and Methodologies. Volume 1: Spatial Cognition in Child and Adult. Hove: Psychology Press, 1997.

Stanton, D., Wilson, P., & Foreman, N. Using virtual reality to aid spatial awareness in disabled children. In P. Sharkey (Ed.), Proceedings of the First International Conference on Disability, Virtual Reality and Associated Technologies, Reading, Berkshire, 1996, 93-101.

Wilson, P., Foreman, N., & Stanton, D. Virtual reality, disability and rehabilitation. (A Review.) Disability and Rehabilitation, 1997a, 19, 213-220.

Wilson, P., Foreman, N., Gillett, R., & Stanton, D. Active versus passive processing of spatial information in a computer simulated environment. Ecological Psychology, 1997b, 9, 207-222.