virtual environments in neuroscience

IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE, VOL. 2, NO. 4, DECEMBER 1998 275

Virtual Environments in NeuroscienceGiuseppe Riva

Abstract—Virtual environments (VE’s) let users navigate andinteract with computer-generated three-dimensional (3-D) en-vironments in real time, allowing for the control of complexstimuli presentation. These VE’s have attracted much attentionin medicine, especially in remote or augmented surgery, andsurgical training, which are critically dependent on hand–eyecoordination. Recently, however, some research projects havebegun to test the possibility of using VE’s for the study andrehabilitation of human cognitive and functional activities.

This paper highlights recent and ongoing research related tothe applications of VE’s in the neuroscience arena. In particular,it focuses on the American and European initiatives in thisfield, including a description of the European Commission (EC)-funded VREPAR projects. Finally, the paper provides a generalintroduction to virtual reality (VR), as it relates to its impact oncognitive and functional abilities.

Index Terms—Biomedical computing, biomedical equipment,biomedical imaging, healthcare, neuropsychology, neuroscience,virtual reality.

I. INTRODUCTION

V IRTUAL environments (VE’s) have recently attractedmuch attention in medicine [1], [2]. Applications of this

technology are being developed for healthcare in the followingareas: surgical procedures (remote surgery or telepresence [3],[4], augmented or enhanced surgery [5], [6], and planningand simulation of procedures before surgery [7], [8]); medicaltherapy [9]–[11]; preventive medicine and patient education[12]; medical education and training [13], [14]; visualizationof massive medical databases [15]; skill enhancement andrehabilitation [16]; and architectural design for healthcarefacilities [17]. As noted by Durlach and Mavor [18], thereare at least four areas of medicine in which VE’s can providea number of advantages (p. 397), as follows.

• Anatomical relations of various organs and systems. Thepossibility of “walking” through the body can facilitatethe acquisition of anatomical knowledge.

• Development of manipulative skills involving precisemotor control and hand–eye coordination. Using VE’s ispossible for the surgeon to practice surgical techniques.

• Image interpretation: augmented-reality systems allow theuser to see virtual information superimposed over realstructures. This makes it easier to identify the often smalldifferences between normal and abnormal images.

Manuscript received April 15, 1998; revised August 10, 1998. This workwas supported by the Commission of the European Communities (CEC),in particular, by the TELEMATICS program (Projects VREPAR—HC 1053—and VREPAR 2—HC 1055—http://www.psicologia.net).

The author is with the Applied Technology for Neuro-Psychology Labo-ratory, Istituto Auxologico Italiano, IRCCS, 28044 Verbania, Italy (e-mail:[email protected]).

Publisher Item Identifier S 1089-7771(98)08872-4.

• Telemedicine through teleoperation. Telemedicine offersthe potential to place medical expertise in a location thatmight not otherwise have access to it.

Recently, however, some research projects have begun to testthe possibility of using VE’s for the study and rehabilitationof human cognitive and functional activities [19]–[24].

This article highlights recent and ongoing research relatedto applications of VE’s and related technologies in the neu-roscience arena. In particular, it focuses on the European andAmerican initiatives in this field. This paper also provides ageneral introduction to virtual reality (VR), as it relates to itsimpact on cognitive and functional abilities.

II. VR AND VE’s

A. Basic Definitions

VR is an emerging technology that alters the way in-dividuals interact with computers. It can be described as“ a fully three-dimensional computer-generated “world”in which a person can move about and interact as if heactually was in an imaginary place. This is accomplishedby totally immersing the person’s senses using a head-mounted display (HMD)” or some other immersive displaydevices, and an interaction device, such as a DataGlove ora joystick [25, p. 111]. However, it is the user immersionin a synthetic environment that characterizes VR as beingdifferent from interactive computer graphics or multimedia.In fact, the sense of presence in a virtual world elicited byimmersive VR technology indicates that VR applications maydiffer fundamentally from those commonly associated withgraphics and multimedia systems [9].

The VE may be displayed on a desktop monitor, a widefield-of-view display, such as a projection screen, or on aHMD. A VE displayed on a wide field-of-view display, whichis fixed in space, is referred to as partially immersive VR.A fully immersive VR environment utilizes a HMD witha head position sensor to control the displayed images sothat they appear to remain stable in space when turning thehead or moving through the VE. A see-through HMD andhead position sensor may be employed to augment the user’sexperience of the real world by superimposing space-stabilizedcomputer-generated images of virtual objects on the user’sview of the outside world.

Unfortunately, the impact of VE’s on cognition is not fullyunderstood. In a recent report, the United States NationalAdvisory Mental Health Council [26, p. 51] suggested that“research is needed to understand both the positive and thenegative effects [of VE’s] on children’s and adult’s per-ceptual and cognitive skills.” Such research will require the

1089–7771/98$10.00 1998 IEEE

276 IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE, VOL. 2, NO. 4, DECEMBER 1998

merging of knowledge from a variety of disciplines, including(but not limited to) neuropsychology, educational theory andtechnology, human factors, medicine, and computer science.Strategies need to be defined to detect any adverse effects ofexposure, some of which may be difficult to anticipate, at anearly stage.

According to Lewis and Griffin [27], exposure managementprotocols for patients in VE’s should include the following:

• screening procedures to detect individuals who maypresent particular risks;

• procedures for managing patient exposure to VR appli-cations so as to ensure rapid adaptation with minimumsymptoms;

• procedures for monitoring unexpected side-effects and forensuring that the system meets its design objectives.

Basic questions pertaining to the structure of human cognitiveprocesses, optimal levels of immersion to facilitate learning,generalization, motion sickness concerns, and computing pa-rameters will need to be considered in an integrative fashionto investigate the usefulness and feasibility of VE’s to be usedin cognitive assessment and rehabilitation [23].

B. PC-Based VE’s: A VR?

Due, in large part, to the significant advances in PC hard-ware that have been made over the last three years, PC-basedVE’s are approaching reality. While the cost of a basic desktopVR system is almost the same, the functionality has improveddramatically, both in terms of graphics processing power andVR hardware, such as HMD’s. The availability of powerful PCengines based on Intel’s Pentium II, Motorola’s Power PC, andDigital’s Alpha processors, and the emergence of reasonablypriced three-dimensional (3-D) accelerator cards allow high-end PC’s to process and display 3-D simulations in real time.

A standard Pentium 266 MMX with as little as 16 Mb ofRAM can offer sufficient processing power for a barebone VRsimulation. A 350 Pentium II with 32 Mb of RAM can providea convincing VE, while a dual 400 Pentium II configurationwith OpenGL acceleration, 128 Mb of RAM and 24 Mb ofVRAM running Windows NT, can match the horsepower ofa graphics workstation.

Immersion is also becoming more affordable. For example,Virtual I-O now has an HMD that costs less than 800 dol-lars and has head tracking built in. Two years ago, HMD’sof the same quality were about ten times more expensive.An HMD with VGA quality is now about 13 000 dollars.However, this price will probably decrease during the nextfive years. Presently, input devices for desktop VR are largelymouse—and joystick-based. These devices, even though theyare not suitable for all applications, can keep costs down andavoid the ergonomic issues of some of the up-to-date I/Odevices, such as 3-D mouses and gloves.

Additionally, software has been greatly improved over thelast three years. It now allows users to create or import 3-Dobjects, apply behavioral attributes, such as weight and gravityto the objects, and program the objects to respond to theuser via visual and/or audio events. Ranging in price fromfree (Alice WTK—http://www.alice.org) to 6000 dollars, the

toolkits are the most functional of the available VR softwareoptions. While some toolkits rely exclusively on C or Cprogramming to build a virtual world, others offer simplerpoint-and-click operations to develop a simulation.

III. VR IN NEUROPSYCHOLOGICAL

ASSESSMENT ANDREHABILITATION (VREPAR)

A. The Rationale

The ability to control a VE and then to introduce a prede-termined set of stimuli can, in theory, enhance the standardapproach used in neuropsychological assessment, whose maingoal is to evaluate how specific activities in the brain areexpressed in observable behaviors [28]. Moreover, the ad-ditional capabilities that are inherent in VE’s can lead togreater flexibility in the adaptation to the patient’s individualproblems, improving the efficacy of the rehabilitation process.

VE’s are highly flexible and programmable. They enable thetherapist to present a wide variety of controlled stimuli and tomeasure and monitor a wide variety of responses made by theuser. Both the synthetic environment itself and the manner inwhich this environment is modified by the user’s responsescan be tailored to the needs of each client and/or therapeuticapplication [29]. It is also possible for the therapist to followthe user into the synthesized world.

More specifically, there are three important characteristics ofVR systems that can offer new methods to neuropsychologicalassessment and rehabilitation [30], as follows.

• How they are controlled:Present alternate computer ac-cess systems accept only one or, at most, two modes ofinput at a time. A computer can be controlled by singlemodes, such as pressing keys on a keyboard, pointing toan on-screen keyboard with a head pointer, or hitting aswitch when the computer presents the desired choice.Present computers do not recognize facial expressions,idiosyncratic gestures, or monitor actions from severalbody parts at a time. Most computer interfaces acceptonly precise, discrete input. Thus, many communicativeacts are ignored and the subtleness and richness of humancommunicative gestures are lost. This results in slow,energy-intensive computer interfacing. VR systems openthe input channel; VR systems have the potential tomonitor movements or actions from any body part ormany body parts at the same time. All properties of amovement, not just contact of a body part with an effector,can be monitored.

• Feedback:VR systems are capable of displaying feedbackin multiple modes; thus, feedback and prompts can betranslated into alternate senses. The environment could bereduced to achieve a larger or overall perspective (withoutthe “looking-through-a-straw” effect usually experiencedwhen using screen readers or tactile displays). Soundscould be translated into vibrations, while environmen-tal noises could be selectively filtered out. Vision isthe primary feedback channel of present-day computers;frequently, a displayed message is further distorted andalienated by text representation. It is very difficult to

RIVA: VIRTUAL ENVIRONMENTS IN NEUROSCIENCE 277

represent force, resistance, density, temperature, pitch,etc., through vision alone. For the individual, multimodalfeedback ensures that the visual channel is not overloaded.

• What is controlled:Until the last decade, computers wereused to control numbers and text by entering numbersand text using a keyboard. Recent direct-manipulationinterfaces have allowed the manipulation of iconic repre-sentations of text files, or two-dimensional (2-D) graphicrepresentations of objects, through pointing devices suchas the mouse. The objective of direct-manipulation envi-ronments was to provide an interface that mimics objectmanipulation in the real world. The latest step in thattrend, VR systems, allows the manipulation of multisen-sory representations of entire environments by naturalactions and gestures.

B. European and American Research

Even if the seminal efforts that gave rise to VR took placein the United States, Europe is playing a leading role inthis research field. In fact, the main applications of VE’sin neuroscience come from Italian, German, and Englishresearchers.

Development of a VR system specifically designed for theassessment and cognitive rehabilitation of cognitive functionsin persons with acquired brain injuries began in Italy [20], [31].Using a standard tool (Wisconsin card sorting test—WCST) ofneuropsychological assessment as a model, these researchershave created a virtual building that requires the person to useenvironmental clues in the selection of appropriate choices(doorways) to navigate through the building. The doorwaychoices vary according to the categories of shape, color, andnumber of portholes. The patient is required to refer to theprevious doorway for clues to appropriately make his/her nextchoice. After the choice criteria is changed, the patient mustshift the cognitive set, analyze clues, and devise a new choicestrategy. The parameters of this system are fully adjustableso that training applications can follow initial standardizedassessments.

Although this VE is not regarded as a substitute for di-agnostic neuropsychological tests, it was used to diagnosebrain dysfunction in selected cases. For instance, the VEwas used to document failures in everyday life coping in apatient with an anterior thalamic stroke [32]. In particular,it produced objective clinical evidence of a persisting frontaldysfunction in spite of an unremarkable result in traditionalneuropsychological tests tapping frontal functions.

Kuhlen et al. [33] are checking the possibility of usingVE’s for improving the diagnosis and therapy of sensorimotordisturbances. Usual examination of sensorimotor disturbancesis based on various functional tests: patients must performmotor tasks that are subsequently analyzed for diagnosticpurposes and therapy planning. In clinical practice, the motordisturbances resulting from cortical and subcortical lesions aredistinguished, but quantitative comparisons are scarce. Evenif cortical and subcortical brain areas extensively exchangeinformation, little is known about this mutual interaction inthe control of sensorimotor integration. Therefore, as noted byKuhlen et al. [33, p. 186], “complex situations are necessary

to examine this sensorimotor network to bring out even subtleimpairments [involving] the use of 3D space information.”This has become only recently possible by using VE’s.

Attree et al. [34] are currently developing VE’s aimedat attention/memory assessment and training. As noted byRizzo and Buckwalter [23], these efforts would be particularlyeffective, as results using traditional methods for memoryrehabilitation have been inconsistent due to the inability tomaintain the patient’s motivation when confronting him/herwith a repetitive series of memory training challenges. VRtraining could potentially address this problem by providingenvironments that initially utilize gaming incentives followedby the gradual fading in of functional environments, with theaim of developing domain-specific memory [35].

The preliminary results [36] support the view that positivetransfer can occur between virtual and real environments.When investigating the transfer of training from a simplesensorimotor virtual task (a “steadiness tester”) to performanceon the real-world equivalent, it was found that final perfor-mance on the real-world task benefited as much from virtualas from real practice. However, these results are not sufficientto simply demonstrate that positive transfer can occur betweenthe virtual and real worlds. Researchers need to understand theprecise conditions (immersive versus nonimmersive; degree ofsimilarity between virtual and real tasks; temporal factors, etc.)that are necessary for transfer to occur.

The two leading VE research groups in the United Statedare the Human Interface Technology Laboratory (HITL), Uni-versity of Washington, Seattle, and the Alzheimer’s DiseaseResearch Center (ADRC), University of Southern California,Los Angeles.

Researchers at HITL use a field-multiplexed head-up videodisplay to simulate an effect, called kinesia paradoxia, totrigger near-normal walking in Akinetic Parkinson’s patients[37], [38]. In particular, normal walking behavior could beelicited by presenting virtual objects and abstract visual cuesmoving through the patient’s visual field at speeds that emulatenormal walking. The research team is currently identifying themost important design parameters of the physical display anddynamic graphics presented.

Researchers at ADRC are working on a VE to be usedfor the assessment and rehabilitation of visuospatial cognitivefunctions. This VE is referred to as mental rotation [23]. Men-tal rotation is designed to present, within a VR environment, atarget stimulus that consists of a specific configuration of 3-Dblocks. After presentation of the target stimuli, the participantis presented with the same set of blocks that need to berotated to the orientation of the target and then superimposedupon it.

This approach will supposedly improve the reliability andvalidity of mental rotation assessment as well as provide anefficient training and rehabilitation option for this aspect ofcognition.

C. VREPAR Projects

If we analyze the results and devices used by the researchdescribed above, we can find at least three technical problemsthat limit their actual application, as follows.


• Cost: Although some attempts have been made to usePC-based VR systems, the majority of the existing VE’sare based on RISC platforms whose cost is beyond thepossibilities of a therapist.

• Lack of reference standards:Almost all of the applicationsin this sector can be considered “one-off” creations tiedto their development hardware and software, which havebeen tuned by a process of trial and error. This makesthem difficult to use in contexts other than those in whichthey were developed.

• Noninteroperability of the systems:Although it is theo-retically possible to use a single VR system for manydifferent applications, none of the existing systems canbe easily adapted to different tasks. This means that twodifferent departments within the same organization mayfind themselves having to use two different VR systemsbecause of the impossibility of adapting one single systemto their different needs.

In order to overcome these shortcomings, the EuropeanCommission recently funded the VREPAR—VR envi-ronment for psycho-neuro-physiological assessment andrehabilitation—projects (HC 1053 and HC 1055). Puttingtogether researchers from Italy, Great Britain, France, andGermany, the projects aim at the following:

a) development of a hardware/software VR modularsystem (VRMS) based on the low cost PC architec-ture (INTEL processor, Windows 95/NT operatingsystem);

b) development of three VRMS modules to be used forthe assessment and treatment of movement, stroke,and body perception disorders.

The research group from Politecnico di Milano, Milan, Italy,developed a VE for the study of the relationship betweenvisual sensory information and the control of movementbeing performed in patients with movement disorders[39], [40].

In order to analyze this relationship, they used a simpletouch task, studied under four different conditions: quickmovement, guided quick movement, VR guided movement,and unguided controlled quick movement. During each task,the patient moves the tip of his/her index finger to a laminaequipped with strain gauge (Fig. 1). Only the movementsof retraction-extension of the index finger of the hand areexamined (Fig. 2). The radial distance between the positionof the metacarpophalangeal articulation and the lamina canbe regulated according to the length of the phalanxes of thepatient’s finger.

The preliminary results obtained from the Milan group[39] show that this approach is suitable for testing both theeffectiveness of various types of visual control and individualperformances in manipulation. An initial therapeutic applica-tion could be the assessment and rehabilitation of patientssuffering from spinal cord injuries.

A second VR module was developed by researchers fromthe University of Reading, U.K., to be used with subjects ex-hibiting attention disorders (neglect) [41]–[43] and movementdisorders (hemiparesis, cerebral palsy) [42], [43]. The settings

Fig. 1. VRMS module for movement disorders.

of this module consist of a series of open or enclosed VE’s thatthe patient can navigate using a bicycle interface. This allowsthe clinician to set tasks at a level appropriate for the patientand to scale the task difficulty as they become accustomed tothe requirements. The tasks used range from simply followingan object to tasks that may require sequencing skills, recogni-tion skills, or semantic tasks (Figs. 3 and 4). The researchersat the University of Reading present an interesting concept:the training will also improve the patient’s fitness level [41],which is hypothesized to improve brain activation as well asother variables relevant to rehabilitative concerns. Experimentsusing clinical subjects are currently underway, with resultsexpected shortly.

Researchers from the Istituto Auxologico Italiano, Verbania,Italy, developed the latest VR module. Its main goals are theassessment [30], [44] and rehabilitation of subjects with bodyexperience disturbances associated with eating- and weight-related problems [44]–[47].

In an immersive VE, the researchers integrated the twomethods (cognitive-behavioral and visual-motorial) commonlyused in the treatment of body experience disturbances (Fig. 5).This approach made it possible to use the psycho-physiologicaleffects provoked by the virtual experience for therapeuticalpurposes. As we have seen above, in every VR system, thehuman operator’s normal sensorimotor loops are altered bythe presence of distortions, time delays, and noise in thesystem. Such effects, attributable to the reorganizational andreconstructive mechanisms necessary to adapt the subjects tothe qualitatively distorted world of VE’s, are of great helpduring the course of a therapy aimed at influencing the way thebody is experienced because they lead to a greater awarenessof the perceptual and sensory/motorial processes [45]–[47].The developed module was tested in two different studies onnonclinical subjects: a first uncontrolled study on 72 male andfemale subjects [45]; a second controlled study on 48 femalesubjects [47]. The results of both studies showed that even ashort-term application of the developed VE was able to modifythe body experience disturbances of the subjects tested. Thenext steps of the project will be the testing of both the effectsof the VE on a clinical sample and the checking of how longthe influence of the VE will last.


Fig. 2. Table with the results of tests, like position and velocity of phalanxes, force exerted on the button, and EMG signal from flexor and extensor muscles.

Fig. 3. World of mazes where navigation requires a patient to follow a colorsequence that is either prompted or remembered.

IV. CONCLUSIONS

VR technology could have a strong impact on neuropsycho-logical assessment and rehabilitation. The key characteristic ofVE’s is the high level of control of the interaction with thetool without the constrains usually found in computer systems.VE’s are highly flexible and programmable. They enable thetherapist to present a wide variety of controlled stimuli andmeasure and monitor a wide variety of responses made by theuser.

However, at this stage, a number of obstacles exist that haveimpeded the development of active research specifically testingpersons with cognitive impairments. These obstacles includeproblems with acquiring funding for an almost untested newtreatment modality, the lack of reference standards, the non-interoperability of the VR systems, and last, but not least,the relative lack of familiarity with the technology from

Fig. 4. World of mazes where navigation requires a patient to recognizeletters in the presence of nonletter distractors. The patient can be presentedwith an interesting navigation task that they can attempt at their own pace,but where they have to attend to and recognize features at different levelsof difficulty.

researchers working in these fields. The VREPAR projectswere a first step toward the solution of some of these problems.Defining as their reference platform a relatively low-costhardware/software solution based on PC’s, these projects couldallow a wider diffusion of this approach.

However, the possible use of VE’s in neuroscience is notlinked to the solution of technical problems only. Actually, theimpact of VE’s on cognition is not fully understood. Manyquestions about the structure of human cognitive processes,motion sickness concerns, and computing parameters will needto be considered by future studies. Such research will requirethe active involvement of a variety of disciplines, includingneurology, psychology, engineering, medicine, and computerscience.


Fig. 5. VRMS module for eating disorders.

In closing, this review underlined how VE’s can offer aunique set of advantages for the delivery of assessment andrehabilitative strategies to persons with cognitive impairments.However, as underlined recently by Rizzo and Buckwalter[23], the “what if” questions in the theoretical musings willnow need to be replaced with “what is” answers, based onobjective studies of the critical issues.

REFERENCES

[1] J. Moline, “Virtual reality in health care: A survey,” inVirtual Reality inNeuro-Psycho-Physiology,G. Riva, Ed. Amsterdam, The Netherlands:IOS, 1997, pp. 3–34.

[2] S. Weghorst, “Virtual reality in medicine [editorial],”Artif. Intell. Med.,vol. 6, pp. 277–279, 1994.

[3] R. M. Satava, “Virtual reality surgical simulator. The first steps,”Surg.Endosc.,vol. 7, pp. 203–205, 1993.

[4] , “Virtual reality and telepresence for military medicine,”Comput.Biol. Med., vol. 25, pp. 229–236, 1995.

[5] R. H. Ossoff and L. Reinisch, “Computer-assisted surgical techniques:A vision for the future of otolaryngology-head and neck surgery,”J.Otolaryngol.,vol. 23, pp. 354–359, 1994.

[6] C. Giorgi, F. Pluchino, M. Luzzara, E. Ongania, and D. S. Casolino,“A computer assisted toolholder to guide surgery in stereotactic space,”Acta. Neurochir. Suppl. (Wien),vol. 61, pp. 43–45, 1994.

[7] G. L. Dunnington and D. A. DaRosa, “Changing surgical educationstrategies in an environment of changing health care delivery systems,”World J. Surg.,vol. 18, pp. 734–737, 1994.

[8] W. K. Muller, R. Ziegler, A. Bauer, and E. H. Soldner, “Virtual reality insurgical arthroscopic training,”J. Image Guid. Surg.,vol. 1, pp. 288–294,1995.

[9] B. O. Rothbaum, L. F. Hodges, R. Kooper, D. Opdyke, J. S. Williford,and M. North, “Effectiveness of computer-generated (virtual reality)graded exposure in the treatment of acrophobia,”Amer. J. Psych.,vol.152, pp. 626–628, 1995.

[10] B. O. Rothbaum, L. Hodges, B. A. Watson, C. D. Kessler, and D.Opdyke, “Virtual reality exposure therapy in the treatment of fear offlying: A case report,”Behav. Res. Ther.,vol. 34, pp. 477–481, 1996.

[11] D. Strickland, G. B. Mesibov, and K. Hogan, “Two case studiesusing virtual reality as a learning tool for autistic children,”J. AutismDevelopmental Disorders,vol. 26, pp. 651–659, 1996.

[12] H. Hoffman, A. Irwin, R. Ligon, M. Murray, and C. Tohsaku, “Virtualreality-multimedia synthesis: Next-generation learning environments formedical education,”J. Biocommun.,vol. 22, pp. 2–7, 1995.

[13] J. R. Merril, N. F. Notaroberto, D. M. Laby, A. M. Rabinowitz, andT. E. Piemme, “The ophthalmic retrobulbar injection simulator (ORIS):An application of virtual reality to medical education,” inProc. Annu.Symp. Comput. Appl. Med. Care,1992, pp. 702–706.

[14] G. L. Merril and V. L. Barker, “Virtual reality debuts in the teachinglaboratory in nursing,”J. Intraven. Nurs.,vol. 19, pp. 182–187, 1996.

[15] J. R. Merril, “Using emerging technologies such as virtual reality andthe world wide web to contribute to a richer understanding of the brain,”Ann. New York Acad. Sci.,vol. 820, pp. 229–33, 1997.

[16] W. J. Greenleaf and M. A. Tovar, “Augmenting reality in rehabilitationmedicine,”Artif. Intell. Med., vol. 6, pp. 289–299, 1994.

[17] D. K. Bowman, “International survey: Virtual-environment research,”IEEE Trans. Comput.,pp. 56–65, Jan. 1995.

[18] N. I. Durlach and A. S. E. Mavor,Virtual Reality: Scientific andTechnological Challenges.Washington, DC: Nat. Acad., 1995.

[19] J. P. Wann and J. D. Turnbull, “Motor skill learning in cerebral palsy:Movement, action and computer—enhanced therapy,”Baillieres Clin.Neurol., vol. 2, pp. 15–28, 1993.

[20] L. Pugnetti, L. Mendozzi, A. Motta, A. Cattaneo, E. Barbieri, and A.Brancotti, “Evaluation and retraining of adults’ cognitive impairment:Which role for virtual reality technology,”Comput. Biol. Med.,vol. 25,pp. 213–227, 1995.

[21] F. D. Rose, E. A. Attree, and D. A. Johnson, “Virtual reality: An assistivetechnology in neurological rehabilitation,”Curr. Opin. Neurol.,vol. 9,pp. 461–467, 1996.

[22] G. Riva, M. Bolzoni, F. Carella, C. Galimberti, M. J. Griffin, C. H.Lewis, R. Luongo, P. Mardegan, L. Melis, L. Molinari-Tosatti, C.Poerschmann, A. Rovetta, S. Rushton, C. Selis, and J. Wann, “Virtualreality environments for psycho-neuro-physiological assessment andrehabilitation,” in Medicine Meets Virtual Reality: Global HealthcareGrid, K. S. Morgan, S. J. Weghorst, H. M. Hoffman, and D. Stredney,Eds. Amsterdam, The Netherlands: IOS, 1997, pp. 34–45.

[23] A. A. Rizzo and J. G. Buckwalter, “Virtual reality and cognitiveassessment and rehabilitation: The state of the art,” inVirtual Reality inNeuro-Psycho-Physiology,G. Riva, Ed. Amsterdam, The Netherlands:IOS, 1997, pp. 123–146.

[24] P. N. Wilson, N. Foreman, and D. Stanton, “Virtual reality, disabilityand rehabilitation,”Disabil. Rehabil.,vol. 19, pp. 213–220, 1997.

[25] R. M. Satava, “Surgery 2001: A technologic framework for the future,”Surg. Endosc.,vol. 7, pp. 111–113, 1993.

[26] “A report of the U.S. National Advisory Mental Health Council,” U.S.Government Printing Office, Washington, DC, NIH Publ. 95-3682, 1995.

[27] C. H. Lewis and M. J. Griffin, “Human factors consideration in clinicalapplications of virtual reality,” inVirtual Reality in Neuro-Psycho-Physiology,G. Riva, Ed. Amsterdam, The Netherlands: IOS, 1997,pp. 35–56.


[28] M. D. Lezak, Neuropsychological Assessment.New York: OxfordUniv. Press, 1995.

[29] K. Glantz, N. I. Durlach, R. C. Barnett, and W. A. Aviles, “Virtual reality(VR) for psychotherapy: From the physical to the social environment,”Psychotherapy,vol. 33, pp. 464–473, 1996.

[30] G. Riva, “Virtual reality in psychological assessment: The body imagevirtual reality scale,”CyberPsychol. Behavior,vol. 1, pp. 37–44, 1998.

[31] L. Pugnetti, L. Mendozzi, E. Barberi, F. D. Rose, and E. A. Attree,“Nervous system correlates of virtual reality experience,” presented atEur. Conf. Disability, Virtual Reality Assoc. Technol.,1996.

[32] L. Mendozzi, A. Motta, E. Barbieri, D. Alpini, and L. Pugnetti, “Theapplication of virtual reality to document coping deficits after a stroke:Report of a case,”CyberPsychol. Behavior,vol. 1, pp. 79–91, 1998.

[33] T. Kuhlen, K. F. Kraiss, A. Szymanski, C. Dohle, H. Hefter, and H. J.Freund, “Virtual holography in diagnosis and therapy of sensorimotordisturbances,” inHealth Care in the Information Age,H. Sieburg, S.Weghorst, and K. Morgan, Eds. Amsterdam, The Netherlands: IOS,1996, pp. 184–193.

[34] E. A. Attree, B. M. Brooks, F. D. Rose, T. K. Andrews, A. G. Leadbetter,and B. R. Clifford, “Memory processes and virtual environments: I can’tremember how I got there. Implications for people with disabilities,”presented atEur. Conf. Disability, Virtual Reality Assoc. Technol.,1996.

[35] E. L. Glisky, “Computer-assisted instruction for patients with traumaticbrain injury: Teaching of domain-specific knowledge,”J. Head TraumaRehab.,vol. 7, pp. 1–12, 1992.

[36] F. D. Rose, E. A. Attree, and B. M. Brooks, “Virtual environments inneuropsychological assessment and rehabilitation,” inVirtual Reality inNeuro-Psycho-Physiology,G. Riva, Ed. Amsterdam, The Netherlands:IOS, 1997, pp. 147–156.

[37] J. D. Prothero, “The treatment of akinesia using virtual images,” HumanInterface Technol. Lab., Seattle, WA, Internal Rep., 1993.

[38] S. J. Weghorst, J. D. Prothero, T. A. Furness, III, D. Anson, and T.Reiss, “Virtual images in the treatment of Parkinson’s disease akinesia,”presented atMed. Meets Virtual Reality II,1994.

[39] A. Rovetta, F. Lorini, and M. R. Canina, “Virtual reality in theassessment of neuromotor diseases: Measurement of time response inreal and virtual environments,” inVirtual Reality in Neuro-Psycho-

Physiology,G. Riva, Ed. Amsterdam, The Netherlands: IOS, 1997,pp. 165–184.

[40] , “A new project for rehabilitation and psychomotor diseaseanalysis with virtual reality support,” inMedicine Meets Virtual Reality,J. D. Westwood, H. H. M., D. Stredney, and S. J. Weghorst, Eds.Amsterdam, The Netherlands: IOS, 1998, pp. 165–184.

[41] S. K. Rushton, K. L. Coles, and J. P. Wann, “Virtual reality technologyin the assessment and rehabilitation of unilateral neglect,” presentedat European Conference on Disability, Virtual Reality and AssociatedTechnology,1996.

[42] J. P. Wann, S. K. Rushton, M. Smyth, and D. Jones, “Rehabilitativeenvironments for attention and movement disorders,”Commun. ACM,vol. 40, pp. 49–52, 1997.

[43] , “Virtual reality for the rehabilitation of disorders of attention andmovement,” inVirtual Reality in Neuro-Psycho-Physiology,G. Riva, Ed.Amsterdam, The Netherlands: IOS, 1997, pp. 157–164.

[44] G. Riva and L. Melis, “Virtual reality in the treatment of body imagedisturbances,” inVirtual Reality in Neuro-Psycho-Physiology,G. Riva,Ed. Amsterdam, The Netherlands: IOS, 1997, pp. 95–112.

[45] G. Riva, “The virtual environment for body-image modification (VE-BIM): Development and preliminary evaluation,”Presence,vol. 6, pp.106–117, 1997.

[46] G. Riva, L. Melis, and M. Bolzoni, “Treating body image disturbances,”Commun. ACM,vol. 40, pp. 69–71, 1997.

[47] G. Riva, “Modifications of body image induced by virtual reality,”Perceptual Motor Skills,vol. 86, pp. 163–170, 1998.

Giuseppe Rivais a Professor of applied social psychology (Psicologia degliAtteggiamenti e delle Opioni) at the University of Cagliari, Sardinia, Italy,and the Head Researcher of the Applied Technology for Neuro-PsychologyLaboratory (ATN-P), Istituto Auxologico Italiano, Verbania, Italy. In theATN-P Laboratory, he researches the methods and assessment tools inpsychology and the use of virtual reality and the Internet in medicine andtraining.

virtual environments in neuroscience

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