Studies in REST

0740-5472/88 $3.00 + .OO Copyright 0 1988 Pergamon Press plc

Journal of Substance Abuse Trearment, Vol. 5. pp. 69-75, 1988 Printed in the USA. All rights reserved.

ORIGINAL

CONTRIBUTION

Studies in REST II. An Overview of REST Technology

G. DAVID COOPER, PhD Maryland Correctional Training Center, Hagerstown, MD

HENRY B. ADAMS, PhD St. Elizabeths Hospital, Washington, DC

Abstract - This paper briefly summarizes current knowledge about Reduced Environmental Stim-

ulation Therapy (REST). Major effects consistently produced by REST include (a) superlearning, (b) optimal physiological and psychological functioning, and (c) diminished denial and defensiveness. Persons showing greatest impairment or psychological disturbance prior to REST typically show the greatest “‘improvement” or change toward optimal levels of functioning afterward. REST facilitates natural homeostatic processes. Despite three decades of overwhelmingly positive research findings, REST technology has thus far received little understanding or acceptance. Common misconceptions about REST (formerly known as ‘Sensory deprivation’) are critically assessed and shown to be unfounded.

Keywords-Alcoholism, substance abuse, sensory deprivation, superlearning, optimal functioning. tial applications. This paper is intended to give readers a brief overview of this emerging technology, its major effects, its past history, common misconceptions, and immediate practical applications. The past history of REST has been marked by persistent misconceptions, confusion, and inappropriate terminology. The current label of REST was only recently adopted. Prior to 1980 the label most widely used was “sensory deprivation,” which was misleading, inaccurate, and carried negative, pejorative connotations for which there was no justification. The unfavorable connotations of the old label fostered prejudices in both popular and professional circles, and as a consequence there was little willingness to assess the merits of REST technology objectively. The key problem of developing appropriate, agreed-upon terminology was recognized long ago (Brownfield, 1965; Rossi, 1969), but resolution of the problem was very slow in coming. Only in recent years did a suitable common terminology begin to evolve. The newly

MOST ALCOHOL and substance abuse treatment profes-

sionals are unfamiliar with the procedures and rationale of the technique now known as Reduced (or Restricted) Environmental Stimulation Therapy (or Treatment), designated by the acronym REST. The first paper reported on the effectiveness of REST in reducing alcohol consumption. Those positive results are typical; comparable results have been obtained with REST in reducing smoking, enhancing weight loss, decreasing hypertension, alleviating psychiatric symptoms, and improving overall mental functioning (Suedfeld, 1980, 1983). REST technology offers a powerful new modality, with a wide range of poten-

The views expressed in this paper are those of the authors, and do not necessarily reflect the views of the Maryland Correctional Training Center, the Maryland Department of Corrections, St. Elizabeths Hospital, or the U.S. Department of Health and Human Services. Requests for reprints should be sent to G. David Cooper, Maryland Correctional Training Center, Hagerstown, MD 21740.

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G.D. Cooper and H.B. Adams

adopted common terminology this paper.

will be employed in

TYPES OF REST ENVIRONMENTS REST technology involves the use of special stimulus environments, in which the total amount of environmental stimulation is drastically reduced to the lowest feasible levels. In these special environments farreaching physiological and psychological changes have been repeatedly observed (Suedfeld, 1980; Zubek, 1969). There are two types of REST environments, which are designated in current terminology as flotation REST and chamber REST. Flotation REST provides the most overall reduction of environmental stimulation, affecting the greatest number of sensory modalities. The techniques of flotation REST have been gradually perfected in recent years (Fine & Turner, 1985; Hutchison, 1984; Lilly, 1977). They involve floating relaxed in a solution of Epsom salts and water in a specially constructed light-proof, sound-proof tank. The salt water counteracts the effects of gravity, producing a subjective sensation of weightlessness. The temperature of the water is thermostatically controlled and kept constant at skin temperature (93.5”F.), where there is no felt sensation of hot or cold. In this environment there is no visual or auditory stimulation (except for the sound of one’s own breathing), and no sensation of gravity or temperature. In chamber REST there is no water and no flotation. Instead, subjects lie on a bed or sit in a chair in a comfortably air-conditioned, silent, dark room or chamber. Visual and auditory stimulation can be reduced to the same low levels as flotation REST. However, anti-gravity stimulation cannot be eliminated, since the body has no bouyancy when it is held by gravity in direct contact with a bed or chair. In chamber REST there is not as much total reduction of sensory stimulation as in flotation REST. Consequently, chamber REST is slower and less potent than flotation REST. It probably takes at least two and a half to three hours of chamber REST to produce most (but not all) of the changes induced by an hour of flotation REST. On the other hand, chamber REST is cheaper and simpler, since flotation REST requires specially constructed tanks, thermostatic controls, pumps, and a salt water solution which must be constantly cleaned, filtered, and closely monitored. Chamber REST requires only a silent (preferably sound-proof), dark, air-conditioned room with a bed or a comfortable chair. The two studies reported in the previous paper on reduced alcohol consumption utilized chamber REST. Since little funding was available, the total direct cost of those two studies was less than $1,000. Most of the REST research of the past three decades

was conducted with chamber REST. The equipment and procedures used in flotation REST were developed, perfected, and commercially marketed only in recent years (Hutchison, 1984). MAJOR EFFECTS PRODUCED

BY BEST

Many publications agree that REST is a powerful technique for the modification of behavior, including behaviors that are diffEult to change by other means. This section summarizes a few of the most important effects of REST, which have been more fully described elsewhere (Brownfield, 1965; Hutchison, 1984; Kammerman, 1977; Schultz, 1%5; Suedfeld, 1980; Zubek, 1969). Superlearning This relatively recent term sums up in one word several psychological effects typically induced by REST. Superlearning is a highly efficient learning process which occurs only under REST conditions. It is to be contrasted with ordinary learning, which is relatively slow, inefficient, and may often result in learning of errors. Ordinary, learning usually takes place in stimulus environments where distracting background stimulation may hamper or interfere with the learning process. Under REST conditions efficient superlearning may occur because irrelevant stimulation is reduced to the lowest possible levels. REST conditions are highly relaxing, facilitating openness to new material. They induce an internal state of “stimulus hunger,” analogous to the stomach’s hunger fur food, in which receptiveness is enhanced. Material learned under REST conditions, including verbal messages, factual information, and motor skills, is more likely to be retained and to influence subsequent behavior than comparable material presented under “normal,” non-REST conditions. (This was clearly illustrated in the previous paper.) In clinical settings, the adverse effects of previously learned maladaptive behaviors can be minimized, allowing for optimally beneficial therapeutic influences, and for the acquisition of new and more effective, socially adaptive, alternative behavior patterns. Learning is a complex process, which can be disrupted by distracting stimulation. REST technology eliminates sources of distraction, creating an optimally efficient learning environment. Optimal Physiological and Psychological Functioning When subjects are placed in a REST environment, measures of their physiological and psychological functioning shift in a homeostatic fashion toward an optimal range. Measures reflecting emotional stress

71

REST Technology

and excessive arousal show reductions. Pulse rates and blood pressure are lowered, and the production of lactic acid and cortisol (which are associated with feelings of anxiety, depression, fatigue, and helplessness) diminish during and after REST. At the same time, the body’s production of natural endorphins increases. These physiological changes are accompanied psychologically by a sense of enhanced well-being (Fine & Turner, 1985; Hutchison, 1984). Many investigators have found slowing of EEG brain wave activity during and after REST. These EEG changes are associated with feelings of calmness and diminished tension, arousal, and anxiety. REST conditions induce a generalized relaxation response, reflected in many physiological measures, including decreased muscle tension, diminished oxygen consumption, deeper and slower respiration, and increased blood flow to the hands, feet, and stomach (Hutchison, 1984). Along with physiological relaxation, REST conditions bring generalized improvement on complex psychological measures of personality, intellectual functioning, and adaptive capacities. IQ scores increase and measures of ego strength improve after REST (Kammerman, 1977). These effects reflect the enhanced intellectual efficiency which occurs when levels of arousal shift in optimal directions. The basic psychological principle involved is the Yerkes-Dodson law, which states that complex, organized mental functions are most likely to be impaired by excessive arousal. The more complex the task, the lower the level of arousal required for the task to be performed most efficiently. Since REST conditions tend to lower arousal to an optimally comfortable range, they facilitate mental functioning, particularly the complex functions which are most adversely affected by too much arousal. Individual

Differences

The effects of REST vary widely from one individual to another. Many of the early reports of REST research at first seemed inconsistent and contradictory, but it subsequently became apparent that insufficient attention had been given to individual differences. A few investigators subsequently made studies of individual differences (Adams, 1965, 1980; Adams, Cooper, & Carrera, 1972/1977; Suedfeld, 1980). These studies agreed that the greater the degree of disturbance or departure from optimal levels of functioning on any measure prior to REST, the greater was the change in the optimal direction afterward. As a group, psychiatric patients and emotionally disturbed individuals showed greater changes toward optimal levels than “normals,” whose everyday functioning is more adaptive. REST conditions facilitate natural homeostatic processes, so that all individuals tend to shift

toward an optimal range of adaptive functioning. The farther they are from this optimum before REST, the greater the change afterward. Diminished

Denial and Defensiveness

REST can be used to facilitate processes of counseling and psychotherapy and to overcome obstacles in treatment. Elimination of irrelevant background stimulation and REST-induced stimulus hunger can be constructively utilized in clinical settings to render clients more open and receptive to planned, positive influences of a beneficial, therapeutic nature. This is especially significant for individuals whose excessive emotional arousal, lack of verbal fluency, defensiveness, repression, and denial make them relatively poor candidates for conventional verbal techniques of counseling and psychotherapy. Non-verbal REST techniques have proven to be particularly effective in those cases (Adams, 1965, 1980; Adams et al., 1972; Fine & Turner, 1985; Kammerman, 1977; Suedfeld, 1980). In view of these considerations, REST procedures are well suited for addressing issues of alcohol and substance abuse, where denial, defensiveness, excessive arousal, and other forms of resistance frequently hamper treatment efforts. These defensive patterns are so often encountered that confrontational techniques are now widely employed in attempts to overcome defensive resistances and to pressure clients into admitting alcohol and/or drug problems. Unfortunately, confrontation is often counterproductive. Confrontational techniques may be perceived by defensive, resistant individuals as a form of criticism or attack, resulting in greater defensiveness, increased emotional arousal, and more rather than less denial. REST offers a positive alternative which may be emotionally more congenial and less threatening to alcohol and substance abusers. Many studies have shown that REST procedures make for a more accurate, realistic self-concept, while at the same time enhancing self-esteem and self-acceptance. Suggestions of a beneficial therapeutic nature are more likely to be accepted under REST conditions than in “normal” stimulus environments (with potentially distracting background stimulation). The feelings of serenity, enhanced well-being, diminished arousal, and improved overall functioning, which typically occur during and after REST, are more conducive to formation of positive relationships in counseling and therapy than confrontational tactics. THE HISTORICAL

DEVELOPMENT

OF REST

Systematic scientific study of the effects of reduced stimulation began in 1954 with the work of Lilly, when he posed the question: “Freed of normal efferent and afferent activities, does the activity of the

72 brain soon become that of coma or sleep, or is there some inherent mechanism which keeps it going?” (Lilly, 1956, p. 1). He set out to investigate this question, using himself as the subject. In order to minimize external stimulation, he used a dark, silent, soundproof tank, in which he floated in water held constantly at skin temperature (93.5”). Lilly’s objective was “to reduce the absolute intensity of all physical stimuli to the lowest possible level” (p. 1). Floating in this tank, there was no sound (except his own breathing and pulse), no light, no visual stimulation, and no sense of heat or cold. Under these conditions he reported that the brain “stays alive despite the lowered levels of input.” He found this novel experience restful and relaxing at first, followed by a “stimulusaction hunger,” and then, if the experience of reduced stimulation continued, there was a gradual process of mental reorganization. In his initial work Lilly used a cumbersome apparatus with a facial mask and tubes for breathing under water. In later years, the procedures and apparatus were simplified and refined. Lilly found that use of an Epsom salt solution caused the body to float supinely on top of the water. Since the head now floated and the face was above water, the need for facial masks and breathing tubes was eliminated. This modification also eliminated gravity as a source of stimulation, as well as the need to make continual postural adjustments to offset the ever-present effects of weight. These changes made for a safe, simple “method of attaining the deepest rest that we have ever experienced” (Lilly, 1977, p. 27). These refinements were subsequently incorporated into specially constructed flotation tanks, which are now available commercially. The term “flotation REST” has been adopted to describe the technique developed by Lilly. As of 1985, there are seven manufacturers of flotation tanks in the United States and others in foreign countries. Numerous flotation centers have been opened, where flotation REST is available to the public for a fee. Historically, .little work was done with flotation REST until recent years. Prior to 1980 almost all the published REST research was conducted using chamber REST. The first studies using chamber REST with psychiatric patients were published by Azima and his associates (Azima & Cramer-Azima, 1956a, 1956b, 1957; Azima, Vispo, & Azima, 1961). They reported that chamber REST consistently produced changes in “improved” directions, but with wide individual differences. Some patients showed substantial improvement, and there were some failures, but in general, the predominant findings were positive. These positive early results were subsequently repeated in other clinical settings. In a 1965 review Brownfield found “nearly unanimous agreement as to the therapeutic value” (p. 131) of chamber REST for

G.D. Cooper and H.B. Adams

psychiatric patients, citing 19 published studies reporting positive results and only one reporting negative or inconclusive results. Chamber REST was not applied to problems of substance abuse until 1972. Since then several studies have reported successful applications of REST to a variety of forms of substance abuse. In 1983 Suedfeld summarized these studies. One typical study on smoking reported that chamber REST, combined with a brief behavioral technique, achieved a 54% drop from initial baseline levels in smoking on a one-year followup. (These results with smoking are comparable to the reduction of alcohol consumption reported in the preceding paper.) A modified form of chamber REST has been recommended as the treatment of choice in the acute stages of PCP psychosis (Adams, 1980; Linder, Lerner, & Burns, 1981; Petersen & Stillman, 1978). Misunderstandings About REST Although extensive research over the past 30 years has repeatedly demonstrated that REST can provide many beneficial effects with minimal risk at low cost, it has received little acceptance or understanding by the public or the professions. Confusion and misunderstandings have been all too common. Only in recent years have there been serious, sustained efforts to address these misunderstandings. The most critical misunderstandings of what is now called “REST technology” stem from two misleading terms which were often linked together for many years: “sensory deprivation” and “brainwashing.” Actually, these terms never described the same psychological processes, but the frequent verbal association of the words in the media fostered the belief that somehow they were the same thing. Careful reading of the original sources shows that there was never any basis for this belief. Sensory Deprivation The term “sensory deprivation” was a semantic blunder. When reports of the effects of reduced and monotonous stimulation first appeared in the early 195Os, the label of “sensory deprivation” was quickly picked up without serious consideration at the time as to its correctness or suitability. Questions regarding its appropriateness were rarely raised until almost three decades later. The word “deprivation” has a literal dictionary definition. It is defined as “the act of depriving, withholding, or taking away by force or threat of force; a state of being deprived; loss; want; bereavement.” Was this the correct word for describing the effects of low-stimulus environments? Published accounts of what was then called “sensory deprivation” reported

REST

Technology

73

no conditions which resembled the dictionary definition of the word “deprivation.” All the studies conducted with human subjects used volunteers who were free to leave at any time. In the literal dictionary sense, there was never any “deprivation” in so-called “sensory deprivation.” Nevertheless, this pejorative label was widely disseminated, first in the media, and subsequently in textbooks, where it had immensely harmful effects. It blurred essential distinctions between special lowstimulus environments and loss or deprivation of the senses, as in blindness or deafness. The unfavorable connotations of the words “sensory deprivation” created a negative set which fostered misconceptions and prejudices, while inhibiting objective assessment of the true merits of this novel technique. Suedfeld’s comprehensive 1980 book, Restricted Environmental Stimulation, began with a frank recognition that the label “sensory deprivation” had been a mistake, and that a more accurate descriptive term was needed. He proposed the acronym REST, for Restricted (or Reduced) Environmental Stimulation Treatment (or Therapy). This acronym abbreviates several long words and suggests implicitly the restful, relaxing, stress-reducing effects which are the most characteristic features of the technique. The new label, REST, has now become widely accepted. The acceptance of this new label may have been a factor in the revival of interest in this area since 1980. In the late 1970s this area, then still known as “sensory deprivation,” was virtually moribund. With the current revival of interest, there is a growing realization that REST technology can offer great benefits when clearly understood and appropriately applied.

Reduced Stimulation

vs. Monotonous

Stimulation

One common misconception about REST is the belief that it causes impaired mental functioning, hallucinations, and other forms of mental disturbance. This misconception became widespread because it appeared in many psychology textbooks, phrased in authoritative-sounding language which implied that the allegedly disruptive effects of reduced stimulation (or “sensory deprivation”) were a scientifically established fact. This misconception reflects carelessness with facts and a lack of first-hand knowledge by psychology textbook writers. Their textbooks usually lump together under the label of “sensory deprivation” two different types of special stimulus environments which produce quite different psychological effects. They fail to make essential distinctions between reduced stimulation (REST) and monotonous stimulation. Extensive research and practical experience have repeatedly demonstrated that short periods of REST bring diminished stress and improved functioning.

This is particularly true of psychiatric patients and substance abusers, who show reduced symptoms and less substance abuse. The more severe the disturbance, as defined by intensity of psychiatric symptoms, substance abuse, test scores, or maladaptive behaviors, the greater is the observed improvement after REST. By contrast, monotonous stimulation has been repeatedly shown to produce impaired mental functioning. There are no research studies which have shown significant improvement after monotonous stimulation on any measures. Since the critical differences between reduced and monotonous stimulation have been so frequently overlooked by textbook writers, it is necessary to explain how and why the significance of these important distinctions went unrecognized. During the early 1950s an influential research project was conducted at McGill University to investigate the effects of long-continued high levels of monotonous, unvarying stimulation (Bexton, Heron, & Scott, 1954). This project was subsequently cited in many psychology textbooks, which referred to the McGill studies as the classical original work on “sensory deprivation.” For many years afterward there was little realization or appreciation of the fact that the monotonous stimulation used in those studies produced disruptive effects quite different from the relaxing effects of chamber REST and flotation REST. Only in recent years was there any clearly-worded, explicit analysis of the fundamental differences between monotonous stimulation and reduced stimulation, or REST (Suedfeld, 1980). The McGill studies were indeed highly significant, but they were subsequently presented in a misleading fashion by many textbooks, along with erroneous conclusions which were never warranted by the original data. In those studies subjects lay for extended periods of time (2 to 6 days) in a small, comfortable, air-conditioned chamber, but this chamber was not dark or silent (unlike chamber REST). Instead, subjects were constantly exposed to fairly high levels of unvarying homogeneous sound (white noise) and diffuse light, seen through translucent goggles which shut off meaningfully patterned visual stimulation. The psychological effects were quite different from those produced by the silence and darkness of REST. The monotonous stimulation used in the McGill studies resulted in impaired cognitive performance, perceptual disturbances, hallucinations, and deterioration of organized mental functioning. Subsequent research elsewhere corroborated these findings and established that high levels of unvarying monotonous stimulation lead to deterioration of complex psychological functions. By contrast, most studies involving reduced environmental stimulation have reported improvement on many physiological and psychological measures (Schultz, 1965; Suedfeld, 1980; Turner & Fine, 1985; Zuckerman, 1979).

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“Brainwashing” and “Sensory Deprivation” Another widespread misconception is the belief that REST is the same thing as “brainwashing.” This belief once had wide currency, because both the popular mass media and psychology textbooks had long associated “brainwashing” with “sensory deprivation.” Close examination of original source materials shows that there is no basis for this belief. “Brainwashing” is a process which is totally unlike reduced environmental stimulation, both in its intentions and in its effects. The word “brainwashing” was coined around 1950 by Edward Hunter, an American journalist, to describe the general overall strategy of the Chinese “thought reform” program. Immediately afterward, during the Korean war, the word came into widespread use all over the world. Hunter never intended the word “brainwashing” to be a vague, general, catch-all label with no explicit meaning. In 1956 he published a book entitled Brainwashing, in which he stated at length, in clear, explicit detail, just what he had in mind when he used the word. The word did not refer to the technique then called “sensory deprivation,” now called REST. Hunter wrote that the word “was picked up so quickly” because “it was not just a clever synonym for something already known, but described a strategy that had yet no name” (Hunter, 1956, p. 3). He spoke of brainwashing not as a single technique, but as a comprehensive political strategy containing many techniques and many tactics. He said that there were two processes: (a) “the conditioning, or softening-up process primarily for control purposes,” and (b) the “indoctrination or persuasion process for conversion purposes” (Hunter, 1956, p. 199). He explained that each process was “composed of a number of different elements. . . found in every case of brainwashing, even though the proportions differ.” The elements were (a) hunger, (b) fatigue, (c) tenseness, (d) threats, (e) violence, (f) drugs, and (g) hypnosis. Hunter noted that drugs and hypnosis were used only in special cases where trained specialists were available. The other elements involve high levels of psychological stress and aversive stimulation. It is clear from Hunter’s description that brainwashing is deliberately intended to produce stressful effects which are the exact opposite of the restful, relaxing, stress-reducing effects of REST. It was a serious error to lump together two dissimilar psychological processes in the mindless fashion which associated “brainwashing” with “sensory deprivation.” Textbooks have long been the major vehicles for disseminating and perpetuating this erroneous association. Indeed, a recent unpublished analysis of 82 psychology textbooks which we conducted showed (a) that they had totally ignored the overwhelmingly posi-

G.D. Cooper and H.B. Adams

tive findings which had actually emerged from decades of REST (“sensory deprivation”) research, and (b) that several textbooks stated flatly that brainwashing consisted of isolation and sensory deprivation, ignoring the explicit descriptions of “brainwashing” by the man who originally coined the word. MAKING EFFECTIVE USE OF REST TECHNOLOGY For readers of this journal, the most important fact about REST technology is its immediate availability today. Readers who question the positive statements about REST in these papers can now experience it for themselves. This is the best way to appreciate its uniquely relaxing, stress-relieving properties. Flotation REST is available for a fee at commercial flotation centers in many communities. Flotation tanks, which can be installed and operated in conjunction with existing programs for both treatment and prevention of alcoholism and substance abuse, may be purchased from a number of manufacturers. Current updated lists of flotation centers and tank manufacturers may be obtained from the Flotation Tank Association, Box 30648, Los Angeles, CA 900304648. Two organizations have been established for the advancement of REST technology: (a) the International REST Investigators’ Society, which is concerned with scientific research in this field, and (b) the Flotation Tank Association, which is involved in practical applications of REST, primarily in commercial settings. Alcoholism and substance abuse professionals can refer clients to flotation centers in their own local communities. The availability of this resource can offer significant benefits for clients and enhance the effectiveness of treatment and prevention efforts. Currently the advertising and promotional literature from flotation centers and tank manufacturers emphasizes the relaxation and stress reduction produced by REST. Relaxation and reduced stress lower excessive arousal, which seems to be a critical causative factor in alcoholism and substance abuse. This critical factor will be explored in the next paper. REFERENCES Adams, H.B. (1965). A case utilizing sensory deprivation. In L.P. Ullmann JL L. Krasner (Eds.), Case studies in behavior modification (pp. 164170). New York: Holt, Rinehart & Winston. Adams, H.B. (1980). Effects of reduced stimulation on institutionalized adult patients. In P. Suedfeld (Ed.), Restricted environmentalstimulation (pp. 320-364). New York: Wiley-Interscience. Adams, H.B., Cooper, G.D., & Carrera, R.N. (1972). Individual differences in behavioral reactions of psychiatric patients to brief partial sensory deprivation. Perceptual and Motor Skills, 34, 199-2171 Reprinted in M. Kammerman (Ed.). (1977). Sensory isolation and personuiity change (pp. 116-141). Springfield, IL: Charles C. Thomas. Azima, H., & Cramer-Azima, F.J. (1956a). Effects of the decrease

REST Technology in sensory variability on body scheme. Canadian Psychiatric Association Journal, 1, 59-12. Azima, H., & Cramer-Azima, F.J. (1956b). Effects of partial isolation in mentally disturbed individuals. Disea.~ of the Nervous System, 17, 117-122. Azima, H., & Cramer-Azima, F.J. (1957). Studies on perceptual isolation. Diseases of the nervous system, 18 (Monograph Supplement), 80-85. Azima, H., Vispo, R., & Axima, F.J. (l%l). Observations on anaclitic therapy during sensory deprivation. In P. Solomon, P.E. Kubzansky, P.H. Leiderman, J.H. Mendelson, R. Trumbull, & D. Wexler (Eds.), Sensory deprivation (pp. 143-160). Cambridge, MA: Harvard University Press. Bexton, W.H.. Heron, W.. & Scott, T.H. (1954). Effects of decreased variation in the sensory environment. Canadian Journal of Psychology, 8, 70-76. Brownfield, C.A. (1965). Isolation. New York: Random House. Fine, T.H., &Turner, J.W. (Eds.) (1985). Proceedings of thefirst international conference on REST and self-regtktion. Toledo, OH: IRIS Publications. Hunter, E. (1956). Brainwashing. New York: Farrar, Straus, & Cudahy. Hutchison, M. (1984). The book offloating. New York:;William Morrow. Kammerman, M. (Ed.). (1977). Sensory isolation and personality change. Springfield, IL: Charles C. Thomas. Lilly, J.C. (1956). Mental effects of reduction of ordinary levels of physical stimuli on intact, healthy persons. Psychiatric Research

75 Reports (No. 5, pp. l-9). Washington: American Psychiatric Association. Lilly, J.C. (1977). The deep se/f. New York: Simon & Schuster. Linder, R.L., Lerner, S.E., & Bums, R.S. (1981). PCP: Thedevil’s dust. Belmont, CA: Wadsworth Publishing Company. Petersen, R.C., & Stillman, R.C. (Eds.) (1978). Phencyclidine (PCP) abuse: An appraisal. Washington, DC: U.S. Government Printing Office. Rossi, A.M. (1969). General methodological considerations. In J.P. Zubek (Ed.), Sensory deprivation: Fifteen years of research (pp. 16-43). New York: Appleton-Century-Crofts. Schultz, D.P. (1965). Sensory restriction. New York: Academic Press. Suedfeld, P. (1980). Restricted environmental stimulation. New York: Wiley-Interscience. Suedfeld, P. (1983). The restricted environmental stimulation technique in the modification of addictive behaviors. Bulletin of the Society of Psychologists in Addictive Behaviors, 2, 231-237. Turner, J.W., 8 Fine, T.H. (1985). Hormonal changes associated with restricted environmental stimulation therapy (REST). In T.H. Fine & J.W. Turner, (Eds.), Proceedings of thejirst international conference on REST and self-regulation (pp. 17-39). Toledo. OH: IRIS Publications. Zubek, J.P. (1%9). Physiological and biochemical effects. In J.P. Zubek (Ed.), Sensor deprivation: Fifeen years of reswrch (pp. 254-288). New York: Appleton-Century-Crofts. Zuckerman, M. (1979). Sensation seeking: Beyond the optimal level of arousal. Hillside, NJ: Erlbaum.