Alterations in Brain and Immune Function in Mindfulness Meditation (2003) PDF

Alterations in Brain and Immune Function Produced by Mindfulness Meditation RICHARD J. DAVIDSON, PHD, JON KABAT-ZINN, PHD, JESSICA SCHUMACHER, MS, MELISSA ROSENKRANZ, BA, DANIEL MULLER, MD, PHD, SAKI F. SANTORELLI, EDD, FERRIS URBANOWSKI, MA, ANNE HARRINGTON, PHD, KATHERINE BONUS, MA, AND JOHN F. SH...

Alterations in Brain and Immune Function Produced by Mindfulness Meditation RICHARD J. DAVIDSON, PHD, JON KABAT-ZINN, PHD, JESSICA SCHUMACHER, MS, MELISSA ROSENKRANZ, BA, DANIEL MULLER, MD, PHD, SAKI F. SANTORELLI, EDD, FERRIS URBANOWSKI, MA, ANNE HARRINGTON, PHD, KATHERINE BONUS, MA, AND JOHN F. SHERIDAN, PHD Objective: The underlying changes in biological processes that are associated with reported changes in mental and physical health in response to meditation have not been systematically explored. We performed a randomized, controlled study on the effects on brain and immune function of a well-known and widely used 8-week clinical training program in mindfulness meditation applied in a work environment with healthy employees. Methods: We measured brain electrical activity before and immediately after, and then 4 months after an 8-week training program in mindfulness meditation. Twenty-five subjects were tested in the meditation group. A wait-list control group (N ⫽ 16) was tested at the same points in time as the meditators. At the end of the 8-week period, subjects in both groups were vaccinated with influenza vaccine. Results: We report for the first time significant increases in left-sided anterior activation, a pattern previously associated with positive affect, in the meditators compared with the nonmedi- tators. We also found significant increases in antibody titers to influenza vaccine among subjects in the meditation compared with those in the wait-list control group. Finally, the magnitude of increase in left-sided activation predicted the magnitude of antibody titer rise to the vaccine. Conclusions: These findings demonstrate that a short program in mindfulness meditation produces demonstrable effects on brain and immune function. These findings suggest that meditation may change brain and immune function in positive ways and underscore the need for additional research. Key words: meditation, mindfulness, EEG, immune function, brain asymmetry, influenza vaccine HIV ⫽ human immunodeficiency virus; NK ⫽ natural killer cell; meditation itself is practiced. Thus, in the current report, we EEG ⫽ electroencephalography; EOG ⫽ electrooculography; PA- focus not on the period of meditation itself, but rather on the NAS ⫽ Positive and Negative Affective Scale; MBSR ⫽ mindful- more enduring changes that can be detected in baseline brain ness-based stress reduction; MANOVA ⫽ multivariate analysis of function as well as brain activity in response to specific variance. emotional challenges. INTRODUCTION We focus on emotion-related brain activity because medi- tation has been found in numerous studies to reduce anxiety W ith the widespread and growing use of meditative prac- tices in hospitals and academic medical centers for outpatients presenting with a range of chronic stress and and increase positive affect (4 – 8). In an extensive corpus of work on the functional neuroanatomical substrates of emotion and affective style, we have established that the frontal regions pain-related disorders and chronic diseases, under the um- of the brain exhibit a specialization for certain forms of brella of what has come to be called mind/body or integrative positive and negative emotion (9, 10). Left-sided activation in medicine, the question of possible biological mechanisms by several anterior regions is observed during certain forms of which meditation may affect somatic, cognitive, and affective positive emotion and in subjects with more dispositional pos- processes becomes increasingly important. Research on the itive affect (10, 11). We therefore hypothesized that because biological concomitants of meditation practice is sparse and meditation decreases anxiety and increases positive affect, has mostly focused on changes that occur during a period of subjects who were practicing meditation should show in- meditation compared with a resting control condition in a creased left-sided activation in these territories compared with single experimental session (1–3). Whereas these studies have those in a wait-list control group. been informative, they tell us little about changes that are Recent studies have established that greater relative left- potentially more enduring. Moreover, virtually all forms of sided anterior activation at baseline is associated with en- meditation profess to alter everyday behavior, effects that are hanced immune function using measures of NK activity (12, by definition not restricted to the times during which formal 13). There has been a paucity of serious research attention to possible immune alterations that might be produced by med- From Laboratory for Affective Neuroscience (R.J.D., J.S., M.R.), Depart- itation (14). This is somewhat surprising in light of the fact ment of Psychology, University of Wisconsin, Madison, Wisconsin; Stress that negative psychosocial influences on immunity have now Reduction Clinic, Division of Preventive and Behavioral Medicine (J.K.-Z., S.F.S., F.U.), Department of Medicine, University of Massachusetts Medical been well established (15–17). Recent research indicates that School, Worcester, Massachusetts; Departments of Medicine and Microbiol- relaxation and stress management procedures increase T-cy- ogy (D.M.), University of Wisconsin Medical School; Department of the totoxic/suppressor (CD3⫹CD) lymphocytes in HIV-infected History of Science (A.H.), Harvard University, Cambridge, Massachusetts; Departments of Preventive Cardiology and Sports Medicine (K.B.), Univer- men (18). On the basis of recent research demonstrating the sity of Wisconsin-Madison Hospitals and Clinics Center for Mindfulness, negative impact of stressful life events on antibody titers in Madison, Wisconsin; and Department of Oral Biology (J.F.S.), College of response to influenza vaccine (19), we vaccinated all subjects Dentistry, Ohio State University, Columbus, Ohio. Address reprint requests to: Richard J. Davidson, PhD, Laboratory for at the end of the 8-week meditation program (in mid Novem- Affective Neuroscience, University of Wisconsin, 1202 W. Johnson St., ber), along with the subjects in wait-list control group at the Madison, WI 53706. Email: [email protected] same time. We hypothesized that the meditators would show Received for publication April 4, 2002; revision received December 27, 2002. greater antibody titers in response to the vaccine compared DOI: 10.1097/01.PSY.0000077505.67574.E3 with the subjects in the wait-list control group. On the basis of 564 Psychosomatic Medicine 65:564 –570 (2003) 0033-3174/03/6504-0564 Copyright © 2003 by the American Psychosomatic Society BRAIN AND IMMUNE FUNCTION IN MEDITATION the association we have previously reported between anterior formal and informal meditative practices that they were instructed to perform activation asymmetry and NK activity, we also predicted that for 1 hour per day, 6 days per week, with the aid of guided audiotapes. The statistical analysis of the data focused on the interactions between the magnitude of change toward greater relative left-sided group (Meditation/Wait-list control) and time (Times 1–3, with the first activation would be associated with a larger increase in anti- assessment occurring before the intervention, Time 2 occurring immediately body titers in response to the vaccine. after the 8-week intervention and Time 3 occurring four months after the training period ended. MANOVAs were computed for each of the four anterior asymmetry measures. In addition to examining main effects and the METHODS interaction, linear trends were also tested. Follow-up ANOVAs on the sepa- Measures of brain electrical activity were recorded before random assign- rate time periods were performed. ment to each of the two groups (Time 1) and then again immediately after (Time 2) and four months after (Time 3) the training period ended. Brain RESULTS electrical activity, or EEG, and EOG (for correcting EEG for eye movements) Affect and Anxiety Measures was recorded during both baseline conditions and in response to a positive and negative emotion induction using methods that have been extensively de- We evaluated self-report measures of positive and negative scribed in previous research (20, 21). EEG was recorded from 27 sites affect and anxiety before and after the training. There was a distributed across the scalp and referenced to linked ears during 8 1-minute significant Group ⫻ Time interaction [F(1,31) ⫽ 5.45, p ⬍ baseline trials, four with eyes open and four with eyes closed, presented in.05] on a measure of trait anxiety, the Spielberger State-Trait counterbalanced order according to our established procedures (22). EEG was Anxiety Inventory (24), accounted for by a reduction in anx- also recorded during a 1-minute period before and a 3-minute period after subjects wrote about one of three of the most positive and negative experi- iety for subjects in the meditation group from Time 1 to Time ences in their life. These events were listed on a questionnaire administered to 2 [t (20) ⫽ 2.86, p ⬍.01; see Figure 1). There was no subjects before the start of the entire protocol. For this task, the EEG was significant Group ⫻ Time interaction on the Positive and aggregated across the 1-minute period before and the 3-minute period after the Negative Affect Scale (23). However, in light of the clear a writing itself. Data were not collected during writing because of movement priori predictions for the meditators to show significant de- artifact. The EEG was parsed into 1.024-second epochs, overlapped by 50% and then processed with the use of a fast Hartley transform method to derive creases in negative affect with treatment, we tested change measures of spectral power density in the ␣-band (8 –13 Hz), which is over time within each group. There was a significant decrease inversely related to activation (20, 22). Asymmetric activation was indexed in trait negative affect with the mediators showing less nega- using an asymmetry score that is computed by subtracting log-transformed tive affect at Times 2 and 3 compared with their negative left hemisphere ␣-power densities from the comparable measure derived from affect at Time 1 [t (20) ⫽ 2.27 and t (21) ⫽ 2.45, respectively, homologous right-sided electrodes. After each of the writing periods, subjects were given the PANAS (23) in p ⬍.05 for both; not shown]. Subjects in the control group state form. In addition, at each assessment, they were administered the showed no change over time in negative affect (t ⬍ 1). PANAS in trait form, along with the Spielberger State-Trait Anxiety Inven- tory (24) in trait form. In addition, subjects in the meditation group were asked Brain Electrical Activity Measures to provide daily reports of the frequency and number of minutes and tech- Based on previous findings linking asymmetric anterior niques of formal meditation practice. Blood draws were then obtained at 3 to 5 weeks and then again at 8 to 9 activation to positive affect, we specifically examined changes weeks after vaccination to examine antibody titers in response to the vaccine in four anterior electrode sites (F3/4, FC7/8, T3/4, and C3/4 in using the hemagglutination inhibition assay (19). the International 10/20 system) during both base-line periods A total of 48 right-handed subjects who were employees of a biotechnol- and in response to the emotion inductions. We computed ogy corporation in Madison, Wisconsin, were recruited to participate. Of MANOVAs with Group and Time (Times 1–3) as factors and these, 41 subjects completed some of the measures for at least two of the assessments. The initial laboratory evaluation was conducted before random examined main effects and interactions, as well as linear group assignment. Subjects were then randomly assigned to the meditation group (N ⫽ 25; 19 female) and the wait-list control group (N ⫽ 16; 10 female) at a ratio of approximately 3:2. There were no differences between groups in the number of subjects who failed to complete the study. Average age of subjects was 36 years and did not differ between group (range ⫽ 23 to 56 years). All but two subjects were white (one Asian-American in the treatment group; one South Asian Indian in the control group). Subjects in the wait-list control group were evaluated at each assessment period along with subjects in the meditation group. After completion of the last assessment, the wait-list control subjects were provided with an 8-week training program comparable to that provided to the subjects in the meditation group. The meditation training (known as MBSR) was delivered by J.K.-Z., and was directly modeled on the MBSR intervention originally developed at the University of Massachusetts Medical Center (25, 26). The effects of MBSR have been reported in numerous clinical studies with diverse populations, as well as in medical students (27, 28). One study demonstrated significant effects of mindfulness on the rate of skin clearing in patients with moderate to severe psoriasis (29) Two recent reviews of MBSR research called for studies to elucidate potential mechanisms of action (30, 31). The training consisted of a class that met weekly for 2.5 to 3 hours per Fig. 1. Mean trait anxiety from the Spielberger State-Trait Anxiety Inven- class, along with a silent seven-hour retreat that was held during week 6 of the tory (24) measured separately by group and time. Error bars reflect course. In addition, subjects were assigned home practice that consisted of means ⫾ SE. Psychosomatic Medicine 65:564 –570 (2003) 565  R. J. DAVIDSON et al. trends. For the baseline period assessments, there was a mar- for the Group ⫻ Time interaction [F(1,27) ⫽ 2.94, p ⬍.10] ginally significant Group ⫻ Time linear trend (F(1,33) ⫽ for the anterior temporal leads. The Group ⫻ Time inter- 3.73, p ⫽.06) and a significant main effect for Group (across action for the Time 1-Time 2 comparison for the anterior time periods; F(1,33) ⫽ 4.57, p ⫽.04). When the comparison temporal region (T3/4) was again in the same direction as of change from baseline for each time period was examined, the other interactions, but not significant [F(1,31) ⫽ 3.16, there was a significant Group ⫻ Time interaction [F(1,37) ⫽ p ⫽.08]. 5.14, p ⬍.05] for the Time 1–3 comparison and a marginally In response to the negative emotion induction for the cen- significant Group ⫻ Time interaction [F(1,33) ⫽ 2.82, p ⫽ tral leads, an omnibus MANOVA revealed a marginally sig-.10] for the Time 1-Time 2 comparison for the central leads nificant Group ⫻ Time interaction [F(2,32) ⫽ 2.78, p ⬍.08], (C3/4). At Time 1, no group differences were present at along with a marginally significant linear trend for this inter- baseline for any region. At both Time 2 and Time 3, medita- action [F(1,33) ⫽ 3.45, p ⫽.07]. In addition, there was a tors showed significantly greater relative left-sided activation significant main effect for Group [F(1,33) ⫽ 6.78, p ⫽.01]. at the central sites (C3/4) compared with the wait-list control For the central leads, the Group ⫻ Time interaction for the group (p ⬍.05 for each; see Figure 2). Time 1-Time 2 comparison was F(1,33) ⫽ 3.62, p ⫽.07, and The omnibus MANOVA performed on the positive emo- for the Time 1-Time 3 comparison it was F(1,37) ⫽ 5.41, p ⬍ tion induction condition revealed a marginally significant.05. Again, there were no group differences in any region at overall Group ⫻ Time interaction [F(2,26) ⫽ 2.52, p ⫽.10] Time 1. At Times 2 and 3, subjects in the meditation group for the anterior temporal (T3/4) electrode leads. When the showed significantly greater left-sided activation (C3/C4) comparison of change from baseline for each time period was compared with subjects in the control group (for Time 2: p ⬍ examined, there was a significant Group ⫻ Time interaction.05; for Time 3: p ⬍.01). The meditators evinced a significant [F(1,30) ⫽ 4.82, p ⬍.05] for the Time 1-Time 2 comparison. This same interaction for the Time 1-Time 3 comparison was increase in left-sided activation in this region from Time 1 to marginally significant and in the same direction [F(1,29) ⫽ Time 2 (p ⬍.05; not shown) and Time 3 (p ⬍.05: Figure 4). 3.46, p ⫽.07]. In response to the positive emotion induction There were no group differences present for any of the at Time 1, no group differences were present in any region. posterior electrodes sites for any of the conditions. However, meditators showed a significant increase in left- sided anterior temporal activation from Time 1 to Time 2 (p ⬍.05), whereas controls showed no change (Figure 3). There Influenza Vaccine Antibody Titers were no other significant Group ⫻ Time interactions for any In response to the influenza vaccine, the meditators dis- other electrode site for the positive emotion induction. played a significantly greater rise in antibody titers from the 4 In response to the negative affect induction, the omnibus to the 8 week blood draw compared with the controls [t(33) ⫽ MANOVA revealed a marginally significant linear trend 2.05, p ⬍.05; Figure 5]. Fig. 2. Means ⫾ SE of asymmetric activation during baseline for subjects in the Meditation group and Control group during Time 1 (before random assignment, before treatment began) and Time 3. The ordinate is an asymmetric metric that represents right minus left log-transformed ␣ power density from the C4/C3 electrode sites. This is a standard index of asymmetric activation (20). Higher numbers on this indicate greater left-sided activation. 566 Psychosomatic Medicine 65:564 –570 (2003) BRAIN AND IMMUNE FUNCTION IN MEDITATION Fig. 3. Means ⫾ SE asymmetric activation (in the T3/T4 electrode sites) in response to the positive emotion induction in the Meditation group and Control group during Times 1 and 2. The ordinate is the same metric of asymmetric activation displayed in Figure 2. Fig. 4. Means ⫾ SE asymmetric activation in response to the negative emotion induction in the Meditation group and Control group during Times 1 and 3. The ordinate is the same metric of asymmetric activation displayed in Figure 2 (C3/C4). Relations Among Measures express the change in activation asymmetry from Time 1 to To examine the relation between the magnitude of increase Times 2 and 3 and correlated the change in activation asym- in left anterior activation and the magnitude of antibody titer metry with the rise in antibody titers, separately for each rise in response to the influenza vaccine from the 4- to 8-week group. Among subjects in the meditation group, those who blood draw, we computed a change score for each subject to showed a greater increase in left-sided activation from Time 1 Psychosomatic Medicine 65:564 –570 (2003) 567  R. J. DAVIDSON et al. Fig. 5. Means ⫾ SE antibody rise from the 3- to 5-week to the 8- to 9-week blood draw in the Meditation and Control groups. The ordinate displays the difference in the log-transformed antibody rise between the 3- to 5- and the 8- to 9-week blood draws derived from the hemagglutination inhibition assay. to Time 2 displayed a larger rise in antibody titers (r ⫽.53, p and EEG measures that showed significant Group ⫻ Time ⬍.05; see Figure 6) while there was no significant relation interactions, as well as antibody titers to influenza vaccine. between these variables for subjects in the control group (r ⫽ There were no significant associations between the measures.26). These correlations were not significantly different. of practice and any of the biological or self-report measures. We also examined correlations between the frequency and Descriptive statistics on these measures of daily practice are duration of reported practice and changes in the self-report provided in Table 1. Fig. 6. Scatter plot for the meditation group only showing the relation between the change in asymmetric anterior activation at baseline from Time 1 to Time 2 in C3/C4 and the magnitude of rise in antibody titers to the influenza vaccine from the week 3 to 5 to the week 8 to 9 blood draw. The meditators that showed the largest magnitude increase in left-sided anterior activation from Time 1 to Time 2 also showed the largest rise in antibody titers from the 3- to 5- to 8- to 9-week blood draws. There was no significant relation between these variables in the control group. 568 Psychosomatic Medicine 65:564 –570 (2003) BRAIN AND IMMUNE FUNCTION IN MEDITATION TABLE 1. Self-Reported Daily Practice in the Meditation Group Time 2 Time 3 Means SD Range Means SD Range How regularly do you practice (0–6 scale) 2.48 2.14 0–6 1.70 1.66 0–6 How long do you practice (0–30 minutes/session) 16.19 min 9.74 0–30 14.21 min 13.36 0–30 How many times have you practiced in the last week? 2.52 2.56 0–7 2.15 2.03 0–7 DISCUSSION larger shift toward left-sided activation further supports earlier These findings are the first to document significant changes associations between these indices (12, 13). in anterior activation asymmetry as a function of meditation There are several limitations of our study that are important training. A variety of previous research has established that to note. First, there was a relatively small number of subjects activation asymmetries in anterior scalp regions are related to who participated and this limited our statistical power. A dispositional affect. Moreover, such asymmetries reflect both number of our hypothesized effects were in the predicted state and trait components (32, 33) with both phasic positive direction, but failed to reach significance. Second, the study mood as well as dispositional positive affect associated with examined the impact of a relatively brief intervention deliv- greater relative left-sided anterior activation. On the basis of ered in a demanding work environment during regular busi- an extensive corpus of both animal and human data, Davidson ness hours. It will be of interest in the future to examine the and colleagues recently suggested (33) that prefrontal activa- changes in brain and immune function produced by MBSR or tion asymmetries are plastic and could be shaped by training. more intensive training in a more conducive learning environ- The findings from this study are the first to suggest that ment. And, finally, the measures of brain function we obtained meditation can produce increases in relative left-sided anterior are relatively crude (see Ref. 20 for a discussion of their activation that are associated with reductions in anxiety and limitations). Future studies should examine the impact of negative affect and increases in positive affect. meditation using more neuroanatomically informative mea- We predicted that we would find significant changes in sures of brain function such as functional magnetic resonance prefrontal as well as central electrode locations. It is unclear imaging. why our most consistent findings were observed at the central Our findings indicate that a short training program in leads (C3/C4), although this is a region where we have ob- mindfulness meditation (MBSR) has demonstrable effects on served reliable affect-related asymmetries in the past (11). brain and immune function and underscores the need for Moreover, we have found robust asymmetric increases in left additional research on the biological consequences of this premotor activation in response to positive emotional pictures intervention. in a study that measured regional glucose metabolism with The authors thank the John D. and Catherine T. MacArthur positron emission tomography (34). The fact that there was no Foundation’s Research Network on Mind-Body interaction, The significant increase in dispositional positive affect in the med- Fetzer Institute, and National Institutes for Mental Health (Grant itation group may be related to the failure to detect increases P50 MH61083), and Anne Skillings for technical support during the in left prefrontal activation. It may well be that if the duration intervention phase of the study. and/or intensity of the intervention were increased, the in- creases would be observed in both positive affect and left prefrontal activation. REFERENCES It is of interest that we observed reliable increases in 1. Lou HC, Kjaer TW, Friberg L, Wildschiodtz G, Holm S, Nowak M. A left-sided activation with training in the meditation group in 150-H2O PET study of meditation and the resting state of normal con- sciousness. Hum Brain Map 1999;7:98 –105. response to both the positive and negative affect induction. 2. 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