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GIUSEPPE RIVA, BRENDA K. WIEDERHOLD, ENRICO MOLINARI (Eds.) Virtual Environments in Clinical Psychology and Neuroscience 1998 © Ios Press: Amsterdam, Netherlands.

VIRTUAL REALITY: A NEW CLINICAL SETTING LAB. 1

C. BOTELLA, 2 C. PERPIÑÁ, 2 R. M. BAÑOS, 1 A. GARCÍA-PALACIOS 1 2

Universitat Jaume I, Spain University of Valencia, Spain

Abstract. Virtual Reality (VR) is a new technology halfway between television and computer. It constitutes another step in the evolution of our use of a tool that allows us to see, to hear and to feel in a world created graphically in three dimensions, and to interact with it. VR is, mainly, a mental experience which makes the user believe that “he is there”, that he is present in the virtual world. With this new tool, the user is no longer a mere observer of that which is happening on a screen, but he “feels” that he is immersed in that world and participates in it, in spite of the fact that they are spaces and objects that only exist in the memory of the computer and in the user’s mind. This chapter seeks to carry out different reflections at different levels. First, we will analyze the relationships between VR and Psychology, one of the disciplines that has made more efforts in order to understand how we obtain knowledge from the world and from ourselves. We will also analyze the impact VR can have in one of the applied disciplines of Psychology, which is Clinical Psychology. With regard to this application environment, VR becomes a tool which can generate useful models for Psychology (both normal and abnormal), and it is offered as a research context for Clinical Psychology; as a “realistic” laboratory where we can study behaviours, emotions, thoughts, etc.; and a new means to develop psychological treatments.

1.

Introduction

The use of tools has been of great importance in the development of the human species. Technology modifies the vision of the world, the culture and, of course, the diverse areas of knowledge which try to describe and to explain the human being, the world, and the relationship between them. For example, modern Cognitive Psychology cannot be understood without the emergence and development of computer. The analogy of mindlike-computer supposed an episthemologic revolution that allowed the study of areas of human functioning considered until then as “metaphysical issues” but they, paradoxically, represent the most distinctive processes in our species. Virtual Reality (VR) is a new technology halfway between television and computer. It constitutes another step in the evolution of our use of a tool that allows us to see, to hear and to feel in a world created graphically in three dimensions, and to interact with it. The term VR was coined in 1989 by Jaron Lanier, although Ivan Sutherland is usually mentioned as the first author who wrote in the sixties about this “illusion generated by a computer.” VR is, mainly, a mental experience which makes the user believe that “he is there”, that he is present in the virtual world. With this new tool, the user is no longer a mere observer of that which is happening on a screen, but he “feels” that he is immersed in that world and participates of it, in spite of the fact that they are spaces and objects that only exist in the memory of the computer and in the user’s mind. The present work seeks to carry out different reflections at different levels. First, we will analyze the relationships between VR and Psychology, one of the disciplines that has made more efforts in order to understand how we obtain knowledge from the world and from ourselves. Both technique and discipline are interested, by different reasons, in one of the most evasive concepts and, however, indispensable to understand, not only our knowledge processes, but even the basis of our “good sense”. We are referring to the concept of reality. We will also analyze the impact VR can have in one of the applied disciplines of Psychology,


which is Clinical Psychology. With regard to this application environment, VR becomes a tool which can generate useful models for Psychology (both normal and abnormal), and it is offered as a research context for Clinical Psychology; as a “realistic” laboratory where we can study behaviours, emotions, thoughts, etc.; and a new means to develop psychological treatments. 2.

The Virtuality of reality

Our system of knowledge has required a development of millions of years to provide us adaptative information, as human beings, of our environment. But if we think that the information we obtain is an exact and trustworthy copy of reality, we make a mistake. Campbell [1] differentiated between the ingenuous realistic’s position, who considers the knowledge of the world as perfect and all the information as accessible and processable by the organism; and the critical realistic’s position who considers that, as a product of the filogenesis, the individual has modeled information by means of the selection of the correlational rules of the mediums in which we settle our categories and, on the other hand, exaggerated the correlational structure of these mediums. In fact, if we experience a phenomenon like that of illusions; it is because the process that mediates between the reality and our representation of it, is fallible. To say it otherwise, and making a pun, our reality is already virtual. Reality is covariating, but we make it falsely constant [2,3]. Tart [4] proposed an interesting comparison between our system of knowledge and VR, that is to say, that each one of us lives “inside” a “world simulation machine”, that our “perceptions” are not other than simulations and they are not reality itself, and we are only aware of the final pattern of neuronal events. The structure of our nervous system (NS) constitutes our stereo headphones, our glasses, our glove, etc. Then, this author considers that our conscience is a mechanism of virtual reality, a simulation of the world. This idea, however, is not novel at all. Helmholtz pointed out, more than one century ago, that the fact that we find objects red, green, cold or hot should not seem so obvious for us: these sensations only belong to our NS and not to the object. Perception is a constructive process by means of which the sensorial data are interpreted as Neisser [5] stated in his perception theories. One of the most attractive issues of VR is that it can reply the sensorial information from the physical world, it can create an analogue of the real world. We should not forget that VR is designed to simulate diverse effects directed to one or more senses, with the purpose that the virtual environment will be indistinguishable, or almost indistinguishable from the real world. As technology is being able to create the impression in the user that something “is there”, or even that he himself “is”, for example, in Mars, the study of the judgments about reality will become, both a necessity, and a challenge. The discussion about the meaning of “real” is, at least, as old as the need that the human being has had of knowing about himself and that which surrounds him, and there has not been any philosophical system which has not tried to give an answer to such a complex question. Regarding Psychology, the study of the attributions about reality judgment is one of its central topics and, in spite of the fact that there is a long tradition in the study of the attributions that people make; there is only very little research about the processes by means of which we judge that something is real. With regard to this issue, we will highlight two models: a) Reality monitoring. Proposed by Johnson and Raye [6].These authors, from the concept of Reality testing, (that is to say, the process through which we distinguish between a current perception and a current act of imagining or remembering), propose a model which explains the discrimination (or the confusion), between a past perception and a past act of imagining or thinking; that is to say, between the memory of the perceptions and the memory of the thoughts or internal representations. In other words, this model tries to elucidate our doubts when we think about “Did I live it or did I only imagine it?”, or about “Now that you have demonstrated it to me, I didn’t say that, but it is so good that I could have said it.” This model has had wide repercussions in Psycopathology,


fundamentally in the study of memory distortions (paramnesias), and in that of perception (hallucinations). b) Reality attribution. This model comes from the Social Psychology field and was proposed by Brickman [7]. It is a model that tries to predict under which conditions people would attribute reality to the facts. Specifically, the performer’s behaviour must have a high internal correspondence and a high external correspondence in order to attribute reality to the events. The internal correspondence refers to the actor’s behaviour reflecting and fitting in with feelings and emotions. In fact, when somebody does not manifest such a relationship, we judge him as a robot. The external correspondence refers to the actor’s behaviour determining and causing a series of consequences in the environment. The experience that a member of our team related to us will be a good example: “I played a computer game in which the image on the screen was the character’s subjective vision that I operated. I pressed a button on the keyboard and, suddenly in my visual field, a muscular arm appeared holding a sophisticated weapon that kept on shooting, killing strange creatures. The shock came when I was aware that the arm was my arm, that it was me who was in that stranger planet and that my shots caused those creatures to be spread on the floor. That is to say, my acts had consequences in that environment.” Now then, we could also go a little further on in our reasoning and wonder: why should we make reality judgments? It seems logical to think that our cognitive system is designed to capture information that is useful to face any emergency; that is to say, if we have survived as a species, it is because we are able to act quickly in response to danger, even when the sensorial evidence (for example, a light crackle of leaves in a solitary plane) is minima [8,9]. Therefore, the fact that our knowledge system is biased toward the belief that the objects are real, especially, when we are under intense emotional conditions, should have some evolutionary advantages. If this bias already exists in the “physical” reality, making correct reality judgments will become a mental challenge, given the fact that VR is, potentially, able not only to reply the sensorial information of the physical world, but also to grant the user the impression of “being there”. In fact, one of the immediate applications of VR in Psychology is its use as an instrument in the study of the attribution processes in reality judgment and, as Shapiro & McDonald [10] point out, as the distinction between the physical atmospheres and those created on-line fades away, people will need to make more and more sophisticated judgments on what is real or not. 3.

The reality of virtuality

VR needn’t copy the physical reality. It is even possible that one of its more attractive issues is to create alternative and fantastic worlds. However, a central question, in this incipient technology, is to achieve “real” realities in which the user does not know how to determine if the environment is real or virtual. And it is in this point where interrelations between Psychology and VR are expected to be promised as more fruitful. What is it which one can offer to the other one? VR can get some of the psychological knowledge to analyze which are the key elements that a good simulation must have to be perceived as “real.” We have already pointed out some of those keys in the previous comment of our bias to believe in the reality of things. To keep this question in mind is important because, perhaps, the first time that the user puts on the helmet, his demand level is smaller, since the effect of novelty and the fascination of a new experience replaces a not very developed software. But, as he is habituated to the new environment, he will demand more and more sophisticated effects, to achieve the sensation of realism. Let us see some of those keys next. 1. First, it is necessary to think that the perceptive indications must be the most similar to those we already know in the physical reality, to increase the ability of mimecry of the experience in function of their sensorial wealth. It allows the information that we already have of the world to have a correspondence with the world that it tries to reply to us.


Now then, our mind is too sophisticated to base everything on sensorial keys. Do you remember when the man arrived to the moon, or more exactly his retransfer by television?. On one side, we have those people we could classify in the section of “to see it is to believe”. Condry [8] tells us that what convinced him more about the reality of what he was watching, was the poor quality of the emission image; that is to say, he inferred that a transmission from the moon in real time with the technology of 1969 should have deficiencies. On the other hand, there are those people who think “or I see it well or I don’t believe it”. And lastly, who has not known somebody of those who think “I don’t believe it although I can see it”?. No matter how much it was explained, their judgment indicated to them that it was impossible to arrive on the moon and it was even more impossible that one could see it on TV. For them, everything had been a masquerade made in one of those modern television studies. This example illustrates to us the complexity of the relationship between sensorial keys and reality judgment. In this way, our mind can be as sophisticated as to conclude that a situation is real, although there is scarce sensorial information, or it is very faulty. An answer to this phenomenon could be that experience and thought indications are, probably, more important than the perceptive wealth (that is what reality monitoring says). Therefore, it will be necessary to have something more. Not only by increasing the sensorial vivacity, will you increase the possibility that people judge as real things that are not, although increasing the sensorial wealth will influence the construction and the reconstruction, because that sensorial wealth “ties” the mental capacity, reducing what is available for the evaluation of reality. 2. Another key to attribute to reality, very bound to the topic of sensorial quality, is that the virtual objects and stories are commendable and familiar in our experience. Although an object looks very real, if it does not exist in the real world, it will be judged as impossible or unlikely. It does not care how real the experience seems, most people will know that they are not really in a rocket heading toward Krypton, neither is Superman greeting them from the window. The most careful analysis of their truthfulness (and, therefore, of doubting about their reality or their fantasy) usually always comes later. 3. We have already commented that our knowledge system is biased toward the belief that objects are real, especially, when we are under intense emotional conditions. Let’s take Brickman’s theory [7], and in this concrete case, one of its elements for reality attribution: the internal correspondence. For example, in phobias (intense and irrational fears), the individual makes exaggerated judgments about the reality of the danger, since his behaviour is maintaining a high internal correspondence with his emotion. In fact, we believe that in the context of VR, the phobic individual will carry out, with higher promptness and trust, reality attributions in a VR environment where the situation he fears is present. Also, we can manipulate the environment until some limits that would be or impossible or very expensive in the real world and create situations of high emotionality for the individual. 4. Another element (perhaps the most impressive and, certainly, the most novel) is immersion. Immersion refers to the degree in which a virtual environment submerges the user’s perceptive system in virtual stimuli. So, for the first time, we have a medium in which, given the fact that virtual environments are three-dimensional spaces, the user can move inside them increasing his conscience that he is in that space, surrounded by it. 5. The possibility of interaction between the user and the environment introduces us a new element: the self as the agent of the experience, which makes the representation of that action have both, the external and internal correspondences, indispensable according to Brickman to attribute reality to the facts. It is no longer the fact of witnessing the things that pass around us, but being surrounded by them, or even causing them. The audience is no more a mere observer and becomes an actor of its own experience. The advance that is taking place in VR will give place to a situation in which we do not need to press buttons neither to guide mice, but when one has the intention or the impulse of taking something,


the virtual arm fits the movement of his own arm, increasing the conscience of being actually there. As we see, the VR systems, at their highest level, not only aspire to create analogues of the real world, but also to produce a sense of presence, the sensation of being present, surrounded by a reality whose perceptive indications are recognized by us, are found believable, they impact us emotionally, and get us to feel present (to be there) in a world that responds to our interaction with it [3]. 4.

Virtual reality and clinical psychology

In this section we will comment some of the applications of VR in Clinical Psychology. Obviously, the utilities of VR in this psychological field can be many and very varied, but here we will only center in some examples of how VR can help both the basic and applied research. 4.1. VR as a research laboratory setting for psychopathology VR can be used as a laboratory setting to study behaviours, emotions, thoughts, etc. But, how can this “laboratory” contribute?. Firstly, the most direct way we have in Psychopathology to find out what happens to a person who has a problem is to ask him/her about it. We can use diverse self-report formats (interviews, questionnaires, logs, etc.). VR doesn’t substitute at all the use of this way of assessing problems, but it extends it, since, we could recreate an atmosphere in which we directly observe what is happening to the person. Certainly, this can not be made with all the psychological problems, but some of them can be susceptible of this analysis. The clearest case is that of phobias. We could place the patient in the open space that he/she fears, or in the crowd he/she avoids, and we can ask him/her to tell us what he/she thinks, what he/she feels, etc. Or we could place him/her in a social meeting and observe how he/she interacts with other people. Tart [4] even proposes that the future diagnosis tests will consist in the client entering diverse standardized virtual reality scenarios which are representative of daily life, to assess the individual’s reactions. It would be something similar to having a selection of work, home, couple fights scenes, etc. Although it seems very suggestive, this technology does not seem to be available in an imminent future. Also, it has the inconvenience that we would have to simulate the different atmospheres and relevant significant people for each particular individual. Anyway, VR allows to study people behaviour in some daily situations. For example, to play certain VR games can provide examples about the ways people act in natural scenarios and not in laboratory setting. This kind of study allows us to observe the behaviour in a context, as well as to analyze the interactions between context and behaviour. As Calvert and Tan [11] point out, VR games have a great potential to explore the paper that situations have in the initiation, maintenance, termination and limitation of human behaviours. Certainly, this strategy has practical and ethical limitations. For example, Tart [4] outlines, as a possibility in order to assess paranoia, to create a virtual environment that begins with a “normal” simulation of a room with some people and then, progressively, to include ambiguous movements, shades, facial expressions and other elements that make the environment more threatening. Certainly, we agree with Begelman [12] who states that this type of applications causes apprehension, since the paranoid VR outlined by Tart seems to have been created to induce paranoia, rather than to assess it. This way, normal people could even begin to feel suspicious and its effect on paranoid patients could be that of increasing the problem. On the other hand, another strategy used in Psychopathology is the use of experimental analogues. For example, the manipulation of emotional states carried out in the laboratory that try to be analogue to those that happen in reality. This way, if we want to know what happens when a person is sad (f.e., how his memory processes work, or how he codes the environment, etc.) you can induce a sad mood in the laboratory. This is usually made by means of imagination, movies, self-referent statements, hypnosis, etc. And, starting from


now, this will also be made by means of VR. In a VR lab, a “emotionally loaded”, scenario could be created, in which the individual could interact. This would bring certain advantages: for example, the researcher would not have the problem of generating an altered state of conscience, as it happens with hypnosis, or he/she would not have the problem that the mood was excessively ephemeral, as it happens with the self-referent statements. These inductions do not only refer to emotional states. For example, before, we commented the critic from Begelman about the assessment of paranoia proposed by Tart, since it could be constituted in an induction of paranoid states in normal people, similar to those of patients. The studies which try to explain if delusions arise as normal explanations of unusual experiences are in a similar line. With this purpose, the explanations which normal subjects give to non voluntary behaviours that they carry out and that have been suggested in previous sessions of hypnosis, have been studied. In the same way, we could study what kind of explanations those subjects give to virtual environments where unusual events happen, as for example, following Tart’s example, to introduce an element from time to time in the periphery of the individual’s vision, but he can never contemplate it clearly. Another strategy, very used at the moment in Psychopathology, consists in the assessment in the laboratory of the patient’s performance in tasks designed to study basic cognitive processes, such as attention, perception, memory, etc. So, from the perspective of Cognitive Experimental Psychopathology, experimental tasks, such as the emotional Stroop, point detection, encoding tasks, etc., are usually used to try to improve issues about internal validity. That is to say, these experimental tasks try to solve a central problem for Psychopathology (the same as for most of Psychology disciplines), the control of the variables. However, when trying to control the strange variables, we usually use stimuli which are presented without a context, usually isolated words, and for that reason they lack of complete meaning, what makes us face problems of ecological validity. That is to say, the cost of increasing the internal validity this way, rebounds many times in the external validity of the experiment. For example, to test the hypothesis that attentional processes play an important role in anxiety disorders, an experiment can present two kinds of stimuli (e.g., emotionally neutral words and threatening words, which represent the individual’s feared object). If the anxious patients detect the threatening stimuli before the neutral ones, we can say attention plays a role in anxiety. However, can we certainly know which part of the real environment an anxious patient will pay attention to, from his performance in a reaction time task where we have presented him isolated words?. Or, to give another example, can we really know how the self-schema of a depresive person will influence the encoding of a continuous and dynamic situation, knowing the way how he/she responds to isolated self-referent words? Leaving apart the fact that words can have different meanings according to the statement where they are placed, there is another issue: the word, the language, only represents the object, but it is not the object, or in terms of Korzybski [13], it is the map but it is not the territory. Certainly, if we want to know how some cognitive processes work, (for example, with an individual with flying fear), it would be better to assess his attentional performance inside an airplane instead of presenting him words like airplane, height, stewardess, etc.,. Obviously, we would meet with many difficulties if we sought to really introduce an individual in an airplane, with an apparatus that monitorized his/her ocular movements, another that monitorized his/her physiologic activity, etc., at the same time that we also fly beside him/her asking him/her about his subjective unit of anxiety. Probably, nowadays it would be difficult to enter an airplane in this way and, possibly, few phobic individuals would offer themselves to participate in such an experience. However, we can make it in a VR laboratory. Imagine for a moment the quantity of variables we could measure and doing so, in a controlled way. For example, we can already find an apparatus that can be settled in a VR helmet which registers, in real time and in a quite reliable way, what the individual is looking at (what exact point of the environment) and how long for. As a conclusion, we would like to stand out that, although we are aware our arguments could seem excessively simple, we believe VR can be a valid and useful laboratory, experimentally speaking. We are not saying it is the best strategy to do research work on


Psychopathology, neither it can substitute others that we are using at the moment. VR only offers us a way which, knowing to use it correctly, is able to overcome some limitations of the strategies we already use and, therefore, it can help us to progress in our way to understanding some psychopathologic phenomenons. 5.

Reality as a therapeutic environment

VR has already begun to give results in the treatment of acrophobia, fear of flying and claustrophobia, and those results are more than promising [14,15,16,17,18]. This is not surprising since, on one hand, many of the issues considered as important in the therapeutic process converge in this new technology and, on the other, it is possible to take advantage of its versatility to optimize therapy [19]. Let’s see it in detail [20]: 1. First, the fact of understanding therapy as a special and protected environment where the patient can begin to explore, to experience and, in definitive, to act, has a great tradition and recognition in all therapy orientations [21]. Now then, the virtual scenario adds something new. In our opinion, it can take part in the “therapeutic alliance”, that is to say, to become a third element to count with. 2. Closely connected with the above-mentioned, the fact of acting without feeling threatened (neither for the external world nor for oneself) is essential. The “as if” of Kelly [22] would exemplify it well. The therapist can make the patient see that the virtual scenario allows him/her to know the situation that he/she has always considered threatening, but the therapist can assure the patient that anyting he/she fears will actually happen. With VR, the patient can freely explore, experience, feel, live, revive current or past feelings and thoughts. Nothing prevents him/her from knowing the world and himself/herself otherwise and, in consequence, to realize he/she can behave and function in that new world in different ways. The person realizes that the world and himself/herself, which were absolutely given, inamovible and finished things, are no other than a simulation, an interpretation that can be changed [4] (from numerous and important vital perspectives). 3. A fundamental strategy used, also, in all the therapy orientations is the role playing. Moreno’s psychodrama, Wolpe and Lazarus’s behavioural role play, or Kelly’s fixed role therapy are good examples of them. Although in this case, VR constitutes a version of the role playing. There are two or more participants (we think, for example, in a software designed for the treatment of social phobia). One of the participants, the patient, plays the classic role; the other one is quite newer, since it is the world itself which is included in the role play; that is to say, it is possible to make the world assumes a new role with which the patient will be able to interact, and even, change it. 4. It is also necessary to remember the great importance that the patient facing his/her fears has in any therapy orientation. VR allows to graduate the situation in such a way that the patient can progress from the easiest performance to the most difficult one. 5. Closely connected with the previous point, it is necessary to remember that, from all the possible sources of self-effectiveness which Bandura [23] contemplates in his theory, the performance achievements are specially useful. From our point of view, VR is an excellent source of information about self-effectiveness in the performance achievements since, without leaving the clinic, different environments can be designed for practically assuring success to the patient in each of his/her “virtual adventures”, and also difficulties, challenges or occasional failures which, later on, can be conquered by the patient, can be suggested. This is to say, it is very important that the patient gets to experience himself as competent and effective. The self-effectiveness theory also predicts that, once established, self-effectiveness is generalized to other situations. Therefore, any advance in the personal functioning can be transferred not only to similar situations, but to others that differ substantially of those which the treatment was focused in.


6. In sixth place, the virtual atmosphere provides additional advantages. On one hand, it is not necessary to wait for the events to take place in the real world (for example, stop of the elevator, flights under storm conditions) but, on the contrary, we can provoke them by means of the software). On the other hand, the possibilities of self-training are vastly enlarged. The patient will be able to work all he/she wants (or all he/she needs) on a certain topic or aspect of the therapy and this fact very probably will strengthen the treatment achievements. Also, it helps us to generalize the advances achieved during therapy, since one can work in different scenarios. 7. Lastly, VR allows to go beyond reality. On one hand, it facilitates that the feared enviroment changes to our convenience. That is to say, VR is flexible enough to design a series of environments the patient can face virtually, not only what he/she fears, but also different issues much more threatening for him/her that VR allows to create. The confrontation and the interaction with the environment can be carried out in very different degrees, and in multiple ways, until getting a true domain. This is, we can achieve the patient to go beyond the feared situation. On the other hand, the goal of the VR does not have to be “to re-create” the “reality.” Rather, we should define therapeutic environments, this is, “to create” environment issues and conditions (which will include vital information for the patient) to which the patient, at the moment, have no access or it is very restricted [24]. Definitively, VR becomes an important therapeutic tool which the patient can use to familiarize, know and interact with the situation that he/she has always considered as threatening. This can also be made, in the measure, the rhythm, and the time the patient wants. Lastly, we would like to insist in the idea that VR is beginning to be considered as an important tool both from basic and applied research, in many and very varied fields. At the moment, the progresses in the development of this technology are even going quicker than what we can advance [4]. It is for that reason that we believe necessary that each study area, and, in this case, the psychological study areas, should meditate on which uses (and abuses) can be made of this new technology. This new form of experience, at the same time, can help us to find answers to questions that we are already thinking about, it can also make new ones arise in the psychological horizon, and not only related with theoretical or empiric questions, but also with ethic ones. This research way has just only begun. Acknowledgments This chapter was partially sponsored by Conselleria Educació i Ciència (Generalitat Valenciana) [GV-D-ES-17-123-96] and Instituto de la Mediana y Pequeña Industria de la Generalitat Valenciana (IMPIVA) [971801003559]. References [1] [2]

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