Journal of Consulting and Clinical Psychology 1976, Vol. 44, No. 3, 4S6--466
Meditation as an Intervention in Stress Reactivity Daniel J. Golcman and Gary E. Schwartz Harvard University Meditation and relaxation were compared for ability to reduce stress reactions in a laboratory threat situation. Thirty experienced meditators and 30 controls cither meditated or relaxed with eyes closed or with eyes open and then watched a stressor film. Stress response was assessed by phasic skin conductance, heart rate, self-report, and personality scales. Meditators and the meditation condition habituated heart rate and phasic skin conductance responses more quickly to the stressor impacts and experienced less subjective anxiety. Meditation can produce a psychophysiological configuration in stress situations opposite to that seen in stress-related syndromes. Research is indicated on clinical applications and on the process whereby meditation state effects may become meditator traits.
Although records and phenomenologic accounts of meditation date back to the Vedic period of India, only in very recent years have there been empirical studies o[ meditation. The changes in psychophysiological state accompanying passive forms of meditation (see Davidson & Schwartz, in press) constitute a configuration opposite to that of a hyperarousal reaction to stress (Gellhorn & Kiely, 1972; Wallace & Benson, 1972). The implications of meditation as an "antidote" for stress reactions (Goleman, 1971) have been tested inferentially in terms of habituation rate (Orme-Johnson, 1973), but thus far there has been no direct assessment of the interaction of the effects of meditation in a stress situation using complex emotional stimuli. This study sought to determine the efficacy of meditation as an intervention in stress, using a laboratory film as stressor in an analogue of emotional arousal to complex stimuli (Lazarus, 1966), in a design systemThis study is based on a doctoral dissertation by the first author, directed by the second author. The research was supported in part by a grant to the first author from the Stouffer Fund, and in part by a subcontract to the second author from the Army Research Projects Agency of the Department of Defense and monitored by the Office of Naval Research under Contract N 0014-70-C-03SO to the San Diego Slate Research University Foundation and by the General Service Foundation. Gary E. Schwartz is now at Yale University. Requests for reprints should be sent to Daniel J. Goleman, Suite 718, 1 Park Avenue, New York, New York 10016.
atically varying both experience as a meditator and meditation itself with appropriate control treatments. From early studies of Indian yogis (Anand, Chhinna, & Singh, 1961; Wenger & Bagchi, 1961) and Zen monks (Kasamatsu & Hirai, 1966) to more recent studies of meditators in America (Banquet, 1973; Wallace, Benson, & Wilson, 1971), a consistent pattern of characteristic state concomitants of passive meditation practices has emerged. Major dependable autonomic trends include slowing of breath and heart rate, decrease in oxygen consumption, lowering or stabilization of blood pressure, decrease in skin conductance, and fewer spontaneous skin conductance responses—a pattern of responses suggesting generalized sympathetic inhibition. Electroencephalogram recording during meditation tends toward a steady decrease in initial beta level and an increase in alpha and then theta as the session progresses, but the progression halts short of sleep, has a pattern of response to external stimuli more like that of waking, and is seldom accompanied by drowsiness. This pattern of response is opposite to Cannon's "fight or flight" defense-alarm syndrome arousal. Meditation may have clinical application in stress-related disorders or it may alleviate the adverse effects of normal daily stress, depending on the resiliency of demonstrated state effects. The significance of meditation as a stress intervention appropriate for daily life might prove major if these meditation
45C,
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
state effects carry over and transform the meditator in a more permanent way, becoming traits. Initial evidence supports this possibility: Meditators as a group have been found to be less anxious (Ferguson & Gowan, in press; Linden, 1973; Nidich, Seeman, & Dreskin, 1973) and more self-actualizing (Seeman, Nidich, & Banta, 1972). The relationship of meditation to stress has been tested inferentially in terms of habituation of skin conductance responses to tones, and meditators have been found to habituate more quickly, implying a more rapid recovery from stress-related arousal (Orme-Johnson, 1973). Stoyva and Budzynski (1973) suggested that with sufficient training the beneficial effects of a low-arousal state in a stressful situation can become habitual, with hyperreactivity to stress being supplanted by a new pattern marked by a lessening of sympathetic arousal in the face of threat. Meditation shares with certain relaxation procedures the induction of a generalized low arousal pattern of responses characterized by sympathetic inhibition, which may prove to inhibit the autonomic activation seen in the stress response. In view of the demonstrated efficacy of relaxation techniques in lessening a stress reaction, and in line with the observed state effects of meditation, the present study was designed to determine whether meditation might be an effective procedure for reducing reactivity to a stressor. The meditation technique employed was transcendental meditation, though the results are seen as generalizable to other passive meditation techniques (Davidson & Schwartz, in press) that meet our proposed definition for "meditation": the systematic and continued focusing of the attention on a single target percept—for example, a mantra or sound—or persistently holding a specific attentional set toward all percepts or mental contents as they spontaneously arise in the field of awareness. Meditation as defined here is different from popular usages that denote contemplation or rumination, as in thinking about a conceptual theme. Meditation per se is the self-regulation of attention, not of belief or other cognitive processes. The design of this study is based on the stress research of Lazarus (1966) and his
457
colleagues, who have provided content-specific reorientations of cognitive set toward a stressor film as effective means for coping with threat. In the present study meditation—an attentional manipulation—was interposed between an initial threat cue and the stressor confrontation in order to alleviate stress reactivity. The predictions were that (a) subjects in a meditation condition would display less autonomic arousal and experience less subjective anxiety in response to a film stressor than would subjects in a relaxation condition and (b) experienced meditators compared with controls would have autonomic response patterns and personality traits more consistent with the expected meditation state effects. METHOD Subjects Sixty subjects were recruited from among two groups: 30 meditators with more than 2 years' experience with transcendental meditation and 30 nonmcditators who were interested in meditation or yoga but practiced neither. Meditators' average age was 25 years, nonmcditators, 23 years; ages ranged from 18 to 31. All subjects were paid for participation. The two sample groups differed on certain background variables in a manner consistent with patterns found in a study of meditator lifestyles (Schwartz, Note 1); significantly reduced usage of licit and illicit drugs, alcohol, cigarettes, and coffee, and dietary changes such as eating less meat and candy.
Apparatus The experimental chamber was a sound-attenuated room containing a comfortable chair for the subject facing a videomonitor 4 feet (1.2 m) away, equipment for attaching electrodes, and an intercom system over which instructions were given. The recording equipment was located in an adjacent room. Skin conductance was monitored via Beckman silver-silver-chloride cup electrodes placed approximately iJ inches (3.8 cm) apart, on the palm of the left hand. Surface oils were removed from the skin by swabbing electrode sites with acetone, and Beckman electrode paste was used as the electrolyte. The signal was directed through a skin conductance coupler (designed by Lykken & Venables, 1971), to a preamplifier and then to two channels of a Grass Model 7 polygraph. One channel provided an alternating current measure of fluctuations in conductance; the time constant of a direct current preamplifier was set at .8, and the sensitivity was set at .2 ^V/cm, displaying skin conductance responses. Heart rate was recorded using metal plate electrocardiogram (EKG) electrodes with Sanborn Redux
458
DANTKI, J. GOf.KMAN AND GARY E. SCHWARTZ
paste as the electrolyte. The electrodes were placed on the left and right upper arms; the raw EKG signal was transmitted through an alternating current preamplifier and displayed on a polygraph channel.
Experimental Procedure Subjects were run individually and were assigned serially to one of three experimental conditions. As each subject came to the laboratory, he was asked to sign a consent form warning of the nature of the stressor film he was to sec and the nature of the measurements to be made. The consent form constituted an initial threat cue (Lazarus, 1966). The subject also filled out the Slate-Trait Anxiety Inventory A-Slate form (Spiclbcrger, Gorsuch, & Lushcnc, 1970). After each subject was conducted to the experimental chamber and seated lacing the videomonitor he filled out the Affect Adjective Check List (Zuckcrman, 1960) in the "Now" form. The experimental procedure was then explained to him, and electrodes were attached. The experiment was divided into four periods, throughout which aulonomic activity was monitored continuously: 4 minutes of baseline, 20 minutes of treatment (with a warning after Minute 18 that treatment would end in 2 minutes), a S-minule posttrcatmcnt rest ending with a warning that a film would begin in 1 minute, and a 12-minute film. After electrodes were detached postfilm, subjects filled out the Affect Adjective Check List for feelings during the treatment and during the accidents portrayed in the film, the Activity Preference Questionnaire (Lykkcn & Katzenmcycr, 1960), the State-Trait Anxiety Inventory A-Slale and A-Trait scales, and the Kyscnck Personality Inventory (Eyscnck & Kyscnck (1968). Specifics of the experimental periods arc as follows: Baseline. Baseline began shortly after the experimenter left the experimental room, having affixed electrodes to the subject and explained the procedure. The subject then was instructed via intercom simply to sit quietly and relax while looking at the blank videoscrccn. This period allowed the subject to become accustomed to the experimental selling and provided a baseline of aulonomic activity. Treatment. After baseline, the subject was given the instructional set for one of three treatment conditions. Subjects within each sample group (meditators and controls) were assigned in serial order to one of three random conditions: meditation, relaxation with eyes open, and relaxation with eyes closed. Subjects in the meditation condition were asked to do transcendental meditation if they were from the experienced meditator group, and the controls were instructed in a simple meditation technique modeled on transcendental meditation. Subjects in the eyesopen condition were lold lo continue to keep their eyes on the screen without actively staring at it, sit relatively still, and relax. Subjects in the eyesclosed condition received similar instructions, except that they were told to relax with their eyes closed, letting their thoughts wander but not dozing off.
The experienced meditators were told not to use their mantra in Ihis condition. Meditation was with eyes closed, and the two relaxation conditions were designed to control for this factor. All treatments lasted for 18 minutes, at which point there was a warning that treatment would end in 2 minutes, during which those in the eyes-open condition were told to close their eyes in order to control for the transition from closed to open eyes at the end of the other trealmenls. Verbatim instructions are given in Goleman (1973). Posttreatment rest. After the 20-minutc treatment all subjects were told to open their eyes, keeping them oriented toward Ihe vidcoscrcen, and were reminded that the film would begin in S minutes. After 4 minutes, subjects were told that the videoscreen was about lo go on and that the, film would start in 1 minute. They were reminded that the film would be about woodworking shop accidents and were lold to watch it as they would any other movie. Film. The film was shown on Ihe videomonitor and lasled approximalcly 12 minules. The film It Didn't Have to Happen has been used as a stressor in many studies of aulonomic reactions lo stress. Originally designed to impress the need for safety practices on wood-mill workers, the film uses actors in a dramatic scenario depicting three shop accidcnls, all caused by poor safety habits: the fingers of a worker are lacerated, a finger of another is cul off, and an innocent bystander is killed by a wooden plank driven through his midscclion as a result of carelessness by a circle-saw operator. These three episodes are invariably marked by both aulonomic reactivity and affective dislurbancc in most subjects; Lazarus, Opton, Nomikos, and Rankin (1965) reported that for every subject Ihe maximum point of skin conductance level and heart rate always occurred within two 10-scc intervals prior lo or following the points of impact in the accident, scenes. Al Ihe end of the film all subjects were told lo continue watching the screen for 2 min.
RESULTS Within groups, the treatment, conditions consistently tended to be ranked similarly to those in the other subject group, both throughout the experimental period and across measures. For this reason only the main effects are reported, by group and by condition, with the exception of the single significant interaction effect. Autonomic Measures The experimental periods were divided into 1-min. segments for purposes of scoring. All measures were adjusted for each subject on the basis of mean values for the baseline period. Segments of minutes during instruc-
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
tions to subjects were not scored, and the treatment period was scored at intervals selected to pick up major trends. Scoring during the film was oriented around the accidents so that the minute immediately before and the minute following the accident impact would be scored. Using accidents as primary division points meant that some of the remaining time blocks were in unscorable segments of less than 60 sec. Analyses of variance were performed on all measures using Data-Text programs in a repeatedmeasures design on the dependent variable with treatment condition and sample group as the independent factors (Armor & Couch, 1971). Phasic Skin Conductance Activity A skin conductance response was defined as an upward needle deflection corresponding to at least .04 ^.V in the absence of any known stimulus (other than the stressor film). Skin conductance responses were scored using values from the base of the pen deflection to the maximum amplitude change before the pen return. The sum of all such responses for each minute was taken as the skin conductance response frequency, the basic measure for analysis of phasic activity. Although there were no significant effects during baseline, there was, as expected, a
459
major trend for all subjects to show a decline in skin conductance response frequency during the treatment period, for time, F (9,486) =3.43, p< .001, leveling off halfway through treatment and rising abruptly with the announcement that treatment would end in 2 minutes. Analyzing results from midway through treatment until the minute prior to the film the meditation condition had the largest posttreatment skin conductance response frequency increase and stayed at the highest frequency throughout most of the posttreatment, prefilm rest: for the Condition X Time interaction, F(22, 594) = 2.39,/>< .001. These trends are shown in Figures 1 and 2. On the average, during the film all cells tended to have response frequency peaks at the accident impact points and troughs before and after impacts: for time, ^(11,594) = 32.73, p < .001. Meditators compared to controls had both higher skin conductance response frequency peaks and lower troughs: for the Group X Time interaction, ^"(11, S94) = 3.97, p < .001. Combining values across accidents into a single composite, the meditator group across all accidents showed a greater increase in skin conductance response frequency during the preimpact minute than did controls, for group, F(l, 54) = 16.32, p< .001, but also showed a greater average de-
BASELINE ~
FIGUKE 1. Skin conductance response frequency during baseline, treatment, and rest by group.
DANIEL J. GOLEMAN AND GARY E. SCHWARTZ
460
SSCR
BY GROUP
UJ i
cr o (f)
6 -
CD
5 ~ A MEDITATOR • NON-MEDITATOR
430 FILM-1 ACCIDENT III
MINUTES FJGXJRE 2. Skin conductance response frequency during film by group.
crease during the postimpact minute than did controls, for group, F(l, 54) = 26.04, p< .001, pointing to a more rapid habituation from stress arousal. Taking the difference between preimpact and postimpact values for all accidents, the meditator group on the average showed a greater decrease than controls, for group, /?(!, 54) = 6.37, p < .05. Because the meditators had higher skin conductance response frequency on the average than controls during the preimpact minute, the significantly larger decrease during
recovery may have been a regression to the mean artifact or due to rebound from an initially higher value. If this difference between anticipatory and postimpact response frequency levels were simply an artifact of the law of initial values, one would predict that there would be no betwcen-group differences in the rate of change. In order to test for an effect due to the law of initial values, 14 subjects from each group were matched with corresponding values from the other group according to anticipatory values
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
and then compared on recovery values. A t test comparing the subjects selected for matching with the remaining subjects in each group showed there to be no significant difference; subjects selected for matching were representative of their respective groups. There was a significant difference between matched groups, with the meditators recovering significantly more than controls from anticipatory arousal levels, £(13) = 2.73, p < .02. Thus, the larger recovery among meditators from anticipatory arousal, rather than merely being an artifact of higher preimpact response levels, is attributable to characteristics of this group. Skin conductance response effects during the film for controls meditating for the first time tended to be congruent with patterns seen in meditators as a group, but they were not nearly as strong. During recovery from the first accident impact the meditation condition among control subjects decreased in response frequency, whereas subjects in the eyes-open condition increased and subjects in the eyes-closed condition did not change: for condition, F ( 2 , 54) = 3.46, p < .05. This recovery pattern did not hold for the second and third accidents. To summarize, the main results were for all groups to decrease equally in response frequency during treatment and for the meditator group to increase more in the anticipatory minute prior to stressor impact and then decrease even more postimpact. The meditator group's recovery pattern was duplicated by the meditation condition, though less strongly. Heart Rate Heart rate was scored as beats per minute and adjusted for values during the first minute of baseline. There was a general trend for all subjects to decelerate in heart rate from the final baseline minute throughout the treatment until the announcement that treatment would end and an increase after this low point until the first posttreatment minute: for time, F(4, 229) = 6.34, p < .001. Deceleration during treatment was greater for controls than for meditators: for group, F (1,54) =3.35, p < .05.
461
During the stressor film on the average all subjects increased in heart rate during the minute prior to the accident impacts and decreased during the postimpact minute: for time, F(4, 229) = 20.74, p < .001. There was a significant group difference in heart rate changes preaccidents and postaccidents; combining values into a composite accident, meditators decelerated from a preimpact mean above the controls to a postimpact level below: for group, F(l, 54) = 6.326, p < .02. As with the skin conductance measure, the possibility was tested that the meditators' greater postimpact recovery was an artifact of the law of initial values rather than an intrinsic group difference in response to stress. Ten meditators and 10 controls matched on preimpact heart rate were compared on recovery values; the meditators' recovery was significantly greater than for controls, £(18) = 4.78, p < .001. As was the case with the parallel skin conductance effect, the meditators' greater recovery from anticipatory arousal is a group characteristic rather than an artifact due to initially higher levels (see Figure 3). The only treatment effect for heart rate was an interaction with subject group for postimpact recovery rate (see Figure 4): Meditators in the meditation condition had the largest recovery decrease, controls in the same condition slightly increased heart rate postimpact, and subjects in the remaining cells had a moderate recovery decrease: for the Group X Condition interaction, F(2, 54) — 5.262, p < .009. The recovery magnitude for the meditator/meditation cell was approximately four times that of the meditator/ eyes-closed cell, t ( 1 8 ) = 2.76, p < .05, and of the control/eycs-closed cell, 2(18) = 3.17, p < .01, and in the opposite direction of the control/meditation cell,
Meditation as an Intervention in Stress Reactivity Daniel J. Golcman and Gary E. Schwartz Harvard University Meditation and relaxation were compared for ability to reduce stress reactions in a laboratory threat situation. Thirty experienced meditators and 30 controls cither meditated or relaxed with eyes closed or with eyes open and then watched a stressor film. Stress response was assessed by phasic skin conductance, heart rate, self-report, and personality scales. Meditators and the meditation condition habituated heart rate and phasic skin conductance responses more quickly to the stressor impacts and experienced less subjective anxiety. Meditation can produce a psychophysiological configuration in stress situations opposite to that seen in stress-related syndromes. Research is indicated on clinical applications and on the process whereby meditation state effects may become meditator traits.
Although records and phenomenologic accounts of meditation date back to the Vedic period of India, only in very recent years have there been empirical studies o[ meditation. The changes in psychophysiological state accompanying passive forms of meditation (see Davidson & Schwartz, in press) constitute a configuration opposite to that of a hyperarousal reaction to stress (Gellhorn & Kiely, 1972; Wallace & Benson, 1972). The implications of meditation as an "antidote" for stress reactions (Goleman, 1971) have been tested inferentially in terms of habituation rate (Orme-Johnson, 1973), but thus far there has been no direct assessment of the interaction of the effects of meditation in a stress situation using complex emotional stimuli. This study sought to determine the efficacy of meditation as an intervention in stress, using a laboratory film as stressor in an analogue of emotional arousal to complex stimuli (Lazarus, 1966), in a design systemThis study is based on a doctoral dissertation by the first author, directed by the second author. The research was supported in part by a grant to the first author from the Stouffer Fund, and in part by a subcontract to the second author from the Army Research Projects Agency of the Department of Defense and monitored by the Office of Naval Research under Contract N 0014-70-C-03SO to the San Diego Slate Research University Foundation and by the General Service Foundation. Gary E. Schwartz is now at Yale University. Requests for reprints should be sent to Daniel J. Goleman, Suite 718, 1 Park Avenue, New York, New York 10016.
atically varying both experience as a meditator and meditation itself with appropriate control treatments. From early studies of Indian yogis (Anand, Chhinna, & Singh, 1961; Wenger & Bagchi, 1961) and Zen monks (Kasamatsu & Hirai, 1966) to more recent studies of meditators in America (Banquet, 1973; Wallace, Benson, & Wilson, 1971), a consistent pattern of characteristic state concomitants of passive meditation practices has emerged. Major dependable autonomic trends include slowing of breath and heart rate, decrease in oxygen consumption, lowering or stabilization of blood pressure, decrease in skin conductance, and fewer spontaneous skin conductance responses—a pattern of responses suggesting generalized sympathetic inhibition. Electroencephalogram recording during meditation tends toward a steady decrease in initial beta level and an increase in alpha and then theta as the session progresses, but the progression halts short of sleep, has a pattern of response to external stimuli more like that of waking, and is seldom accompanied by drowsiness. This pattern of response is opposite to Cannon's "fight or flight" defense-alarm syndrome arousal. Meditation may have clinical application in stress-related disorders or it may alleviate the adverse effects of normal daily stress, depending on the resiliency of demonstrated state effects. The significance of meditation as a stress intervention appropriate for daily life might prove major if these meditation
45C,
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
state effects carry over and transform the meditator in a more permanent way, becoming traits. Initial evidence supports this possibility: Meditators as a group have been found to be less anxious (Ferguson & Gowan, in press; Linden, 1973; Nidich, Seeman, & Dreskin, 1973) and more self-actualizing (Seeman, Nidich, & Banta, 1972). The relationship of meditation to stress has been tested inferentially in terms of habituation of skin conductance responses to tones, and meditators have been found to habituate more quickly, implying a more rapid recovery from stress-related arousal (Orme-Johnson, 1973). Stoyva and Budzynski (1973) suggested that with sufficient training the beneficial effects of a low-arousal state in a stressful situation can become habitual, with hyperreactivity to stress being supplanted by a new pattern marked by a lessening of sympathetic arousal in the face of threat. Meditation shares with certain relaxation procedures the induction of a generalized low arousal pattern of responses characterized by sympathetic inhibition, which may prove to inhibit the autonomic activation seen in the stress response. In view of the demonstrated efficacy of relaxation techniques in lessening a stress reaction, and in line with the observed state effects of meditation, the present study was designed to determine whether meditation might be an effective procedure for reducing reactivity to a stressor. The meditation technique employed was transcendental meditation, though the results are seen as generalizable to other passive meditation techniques (Davidson & Schwartz, in press) that meet our proposed definition for "meditation": the systematic and continued focusing of the attention on a single target percept—for example, a mantra or sound—or persistently holding a specific attentional set toward all percepts or mental contents as they spontaneously arise in the field of awareness. Meditation as defined here is different from popular usages that denote contemplation or rumination, as in thinking about a conceptual theme. Meditation per se is the self-regulation of attention, not of belief or other cognitive processes. The design of this study is based on the stress research of Lazarus (1966) and his
457
colleagues, who have provided content-specific reorientations of cognitive set toward a stressor film as effective means for coping with threat. In the present study meditation—an attentional manipulation—was interposed between an initial threat cue and the stressor confrontation in order to alleviate stress reactivity. The predictions were that (a) subjects in a meditation condition would display less autonomic arousal and experience less subjective anxiety in response to a film stressor than would subjects in a relaxation condition and (b) experienced meditators compared with controls would have autonomic response patterns and personality traits more consistent with the expected meditation state effects. METHOD Subjects Sixty subjects were recruited from among two groups: 30 meditators with more than 2 years' experience with transcendental meditation and 30 nonmcditators who were interested in meditation or yoga but practiced neither. Meditators' average age was 25 years, nonmcditators, 23 years; ages ranged from 18 to 31. All subjects were paid for participation. The two sample groups differed on certain background variables in a manner consistent with patterns found in a study of meditator lifestyles (Schwartz, Note 1); significantly reduced usage of licit and illicit drugs, alcohol, cigarettes, and coffee, and dietary changes such as eating less meat and candy.
Apparatus The experimental chamber was a sound-attenuated room containing a comfortable chair for the subject facing a videomonitor 4 feet (1.2 m) away, equipment for attaching electrodes, and an intercom system over which instructions were given. The recording equipment was located in an adjacent room. Skin conductance was monitored via Beckman silver-silver-chloride cup electrodes placed approximately iJ inches (3.8 cm) apart, on the palm of the left hand. Surface oils were removed from the skin by swabbing electrode sites with acetone, and Beckman electrode paste was used as the electrolyte. The signal was directed through a skin conductance coupler (designed by Lykken & Venables, 1971), to a preamplifier and then to two channels of a Grass Model 7 polygraph. One channel provided an alternating current measure of fluctuations in conductance; the time constant of a direct current preamplifier was set at .8, and the sensitivity was set at .2 ^V/cm, displaying skin conductance responses. Heart rate was recorded using metal plate electrocardiogram (EKG) electrodes with Sanborn Redux
458
DANTKI, J. GOf.KMAN AND GARY E. SCHWARTZ
paste as the electrolyte. The electrodes were placed on the left and right upper arms; the raw EKG signal was transmitted through an alternating current preamplifier and displayed on a polygraph channel.
Experimental Procedure Subjects were run individually and were assigned serially to one of three experimental conditions. As each subject came to the laboratory, he was asked to sign a consent form warning of the nature of the stressor film he was to sec and the nature of the measurements to be made. The consent form constituted an initial threat cue (Lazarus, 1966). The subject also filled out the Slate-Trait Anxiety Inventory A-Slate form (Spiclbcrger, Gorsuch, & Lushcnc, 1970). After each subject was conducted to the experimental chamber and seated lacing the videomonitor he filled out the Affect Adjective Check List (Zuckcrman, 1960) in the "Now" form. The experimental procedure was then explained to him, and electrodes were attached. The experiment was divided into four periods, throughout which aulonomic activity was monitored continuously: 4 minutes of baseline, 20 minutes of treatment (with a warning after Minute 18 that treatment would end in 2 minutes), a S-minule posttrcatmcnt rest ending with a warning that a film would begin in 1 minute, and a 12-minute film. After electrodes were detached postfilm, subjects filled out the Affect Adjective Check List for feelings during the treatment and during the accidents portrayed in the film, the Activity Preference Questionnaire (Lykkcn & Katzenmcycr, 1960), the State-Trait Anxiety Inventory A-Slale and A-Trait scales, and the Kyscnck Personality Inventory (Eyscnck & Kyscnck (1968). Specifics of the experimental periods arc as follows: Baseline. Baseline began shortly after the experimenter left the experimental room, having affixed electrodes to the subject and explained the procedure. The subject then was instructed via intercom simply to sit quietly and relax while looking at the blank videoscrccn. This period allowed the subject to become accustomed to the experimental selling and provided a baseline of aulonomic activity. Treatment. After baseline, the subject was given the instructional set for one of three treatment conditions. Subjects within each sample group (meditators and controls) were assigned in serial order to one of three random conditions: meditation, relaxation with eyes open, and relaxation with eyes closed. Subjects in the meditation condition were asked to do transcendental meditation if they were from the experienced meditator group, and the controls were instructed in a simple meditation technique modeled on transcendental meditation. Subjects in the eyesopen condition were lold lo continue to keep their eyes on the screen without actively staring at it, sit relatively still, and relax. Subjects in the eyesclosed condition received similar instructions, except that they were told to relax with their eyes closed, letting their thoughts wander but not dozing off.
The experienced meditators were told not to use their mantra in Ihis condition. Meditation was with eyes closed, and the two relaxation conditions were designed to control for this factor. All treatments lasted for 18 minutes, at which point there was a warning that treatment would end in 2 minutes, during which those in the eyes-open condition were told to close their eyes in order to control for the transition from closed to open eyes at the end of the other trealmenls. Verbatim instructions are given in Goleman (1973). Posttreatment rest. After the 20-minutc treatment all subjects were told to open their eyes, keeping them oriented toward Ihe vidcoscrcen, and were reminded that the film would begin in S minutes. After 4 minutes, subjects were told that the videoscreen was about lo go on and that the, film would start in 1 minute. They were reminded that the film would be about woodworking shop accidents and were lold to watch it as they would any other movie. Film. The film was shown on Ihe videomonitor and lasled approximalcly 12 minules. The film It Didn't Have to Happen has been used as a stressor in many studies of aulonomic reactions lo stress. Originally designed to impress the need for safety practices on wood-mill workers, the film uses actors in a dramatic scenario depicting three shop accidcnls, all caused by poor safety habits: the fingers of a worker are lacerated, a finger of another is cul off, and an innocent bystander is killed by a wooden plank driven through his midscclion as a result of carelessness by a circle-saw operator. These three episodes are invariably marked by both aulonomic reactivity and affective dislurbancc in most subjects; Lazarus, Opton, Nomikos, and Rankin (1965) reported that for every subject Ihe maximum point of skin conductance level and heart rate always occurred within two 10-scc intervals prior lo or following the points of impact in the accident, scenes. Al Ihe end of the film all subjects were told lo continue watching the screen for 2 min.
RESULTS Within groups, the treatment, conditions consistently tended to be ranked similarly to those in the other subject group, both throughout the experimental period and across measures. For this reason only the main effects are reported, by group and by condition, with the exception of the single significant interaction effect. Autonomic Measures The experimental periods were divided into 1-min. segments for purposes of scoring. All measures were adjusted for each subject on the basis of mean values for the baseline period. Segments of minutes during instruc-
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
tions to subjects were not scored, and the treatment period was scored at intervals selected to pick up major trends. Scoring during the film was oriented around the accidents so that the minute immediately before and the minute following the accident impact would be scored. Using accidents as primary division points meant that some of the remaining time blocks were in unscorable segments of less than 60 sec. Analyses of variance were performed on all measures using Data-Text programs in a repeatedmeasures design on the dependent variable with treatment condition and sample group as the independent factors (Armor & Couch, 1971). Phasic Skin Conductance Activity A skin conductance response was defined as an upward needle deflection corresponding to at least .04 ^.V in the absence of any known stimulus (other than the stressor film). Skin conductance responses were scored using values from the base of the pen deflection to the maximum amplitude change before the pen return. The sum of all such responses for each minute was taken as the skin conductance response frequency, the basic measure for analysis of phasic activity. Although there were no significant effects during baseline, there was, as expected, a
459
major trend for all subjects to show a decline in skin conductance response frequency during the treatment period, for time, F (9,486) =3.43, p< .001, leveling off halfway through treatment and rising abruptly with the announcement that treatment would end in 2 minutes. Analyzing results from midway through treatment until the minute prior to the film the meditation condition had the largest posttreatment skin conductance response frequency increase and stayed at the highest frequency throughout most of the posttreatment, prefilm rest: for the Condition X Time interaction, F(22, 594) = 2.39,/>< .001. These trends are shown in Figures 1 and 2. On the average, during the film all cells tended to have response frequency peaks at the accident impact points and troughs before and after impacts: for time, ^(11,594) = 32.73, p < .001. Meditators compared to controls had both higher skin conductance response frequency peaks and lower troughs: for the Group X Time interaction, ^"(11, S94) = 3.97, p < .001. Combining values across accidents into a single composite, the meditator group across all accidents showed a greater increase in skin conductance response frequency during the preimpact minute than did controls, for group, F(l, 54) = 16.32, p< .001, but also showed a greater average de-
BASELINE ~
FIGUKE 1. Skin conductance response frequency during baseline, treatment, and rest by group.
DANIEL J. GOLEMAN AND GARY E. SCHWARTZ
460
SSCR
BY GROUP
UJ i
cr o (f)
6 -
CD
5 ~ A MEDITATOR • NON-MEDITATOR
430 FILM-1 ACCIDENT III
MINUTES FJGXJRE 2. Skin conductance response frequency during film by group.
crease during the postimpact minute than did controls, for group, F(l, 54) = 26.04, p< .001, pointing to a more rapid habituation from stress arousal. Taking the difference between preimpact and postimpact values for all accidents, the meditator group on the average showed a greater decrease than controls, for group, /?(!, 54) = 6.37, p < .05. Because the meditators had higher skin conductance response frequency on the average than controls during the preimpact minute, the significantly larger decrease during
recovery may have been a regression to the mean artifact or due to rebound from an initially higher value. If this difference between anticipatory and postimpact response frequency levels were simply an artifact of the law of initial values, one would predict that there would be no betwcen-group differences in the rate of change. In order to test for an effect due to the law of initial values, 14 subjects from each group were matched with corresponding values from the other group according to anticipatory values
MEDITATION AS AN INTERVENTION IN STRESS REACTIVITY
and then compared on recovery values. A t test comparing the subjects selected for matching with the remaining subjects in each group showed there to be no significant difference; subjects selected for matching were representative of their respective groups. There was a significant difference between matched groups, with the meditators recovering significantly more than controls from anticipatory arousal levels, £(13) = 2.73, p < .02. Thus, the larger recovery among meditators from anticipatory arousal, rather than merely being an artifact of higher preimpact response levels, is attributable to characteristics of this group. Skin conductance response effects during the film for controls meditating for the first time tended to be congruent with patterns seen in meditators as a group, but they were not nearly as strong. During recovery from the first accident impact the meditation condition among control subjects decreased in response frequency, whereas subjects in the eyes-open condition increased and subjects in the eyes-closed condition did not change: for condition, F ( 2 , 54) = 3.46, p < .05. This recovery pattern did not hold for the second and third accidents. To summarize, the main results were for all groups to decrease equally in response frequency during treatment and for the meditator group to increase more in the anticipatory minute prior to stressor impact and then decrease even more postimpact. The meditator group's recovery pattern was duplicated by the meditation condition, though less strongly. Heart Rate Heart rate was scored as beats per minute and adjusted for values during the first minute of baseline. There was a general trend for all subjects to decelerate in heart rate from the final baseline minute throughout the treatment until the announcement that treatment would end and an increase after this low point until the first posttreatment minute: for time, F(4, 229) = 6.34, p < .001. Deceleration during treatment was greater for controls than for meditators: for group, F (1,54) =3.35, p < .05.
461
During the stressor film on the average all subjects increased in heart rate during the minute prior to the accident impacts and decreased during the postimpact minute: for time, F(4, 229) = 20.74, p < .001. There was a significant group difference in heart rate changes preaccidents and postaccidents; combining values into a composite accident, meditators decelerated from a preimpact mean above the controls to a postimpact level below: for group, F(l, 54) = 6.326, p < .02. As with the skin conductance measure, the possibility was tested that the meditators' greater postimpact recovery was an artifact of the law of initial values rather than an intrinsic group difference in response to stress. Ten meditators and 10 controls matched on preimpact heart rate were compared on recovery values; the meditators' recovery was significantly greater than for controls, £(18) = 4.78, p < .001. As was the case with the parallel skin conductance effect, the meditators' greater recovery from anticipatory arousal is a group characteristic rather than an artifact due to initially higher levels (see Figure 3). The only treatment effect for heart rate was an interaction with subject group for postimpact recovery rate (see Figure 4): Meditators in the meditation condition had the largest recovery decrease, controls in the same condition slightly increased heart rate postimpact, and subjects in the remaining cells had a moderate recovery decrease: for the Group X Condition interaction, F(2, 54) — 5.262, p < .009. The recovery magnitude for the meditator/meditation cell was approximately four times that of the meditator/ eyes-closed cell, t ( 1 8 ) = 2.76, p < .05, and of the control/eycs-closed cell, 2(18) = 3.17, p < .01, and in the opposite direction of the control/meditation cell,
