Buddha’s Brain

in the SPOTLIGHT Richard J. Davidson and Antoine Lutz Buddhas Brain Neuro malleableity and speculation I n a recent visit to the United States, the Dalai genus Lama gave a speech at the Society for Neurosciences annual get together in Washington, D. C. Over the past several years, he has helped recruit Tibetan Buddhisticic monks for and directly encouragedresearch on the wizardry and venture in the Waisman Laboratory for Brain Imaging and Behavior at the University of WisconsinMadison.The decisions from studies in this unusual sample, as well as related research efforts, advise that eachwhere the trail of meditating for tens of thousands of hours, the long-term practiti unitaryrs had actually altered the structure and turn of their brains. In this article we discuss neuroplasticity, which encompasses such alterations, and the findings from these studies. Further, we comment on the associated prefigure processing (SP) challenges, the current status, and how SP rat contri howevere to advancing these studies. WHAT IS NEUROPLASTICITY?The term neuroplasticity is use to describe the brain changes that croak in retort to experience. There ar some disparate mechanisms of neuroplasticity, ranging from the growth of new connections to the creation of new neurons. When the theoretical account of neuroplasticity is applied to surmise, we suggest that the amiable cultivation of venture is fundamentally nonedifferent than opposite forms of skill acquisition that can induce plastic changes in the brain 1, 2. WHAT IS MEDITATION? The term meditation refers to a resistant variety of places, ranging from techDigital Object Identifier 10. 109/MSP. 2007. 910429 niques designed to promote relaxation to exercises, performed with a to a great extent farr for each oneing culture such as a heightened sense of well-being. It is thus inwrought to be specific about the type of meditation practice to a lower place investigation. In 3, meditation was conceptua lized as a family of complex steamy and perplexityal regulatory strategies developed for various ends, including the cultivation of well-being Buddhist Vipassan? and Mah? mudr? , a a a and argon also implicated in many popular secular interventions that draw on Buddhist practices.FINDINGS OF BRAIN CHANGES IN MEDITATION In what follows, we summarize the changes in the brain that occur during each of these styles of meditation practice. Such changes include alterations in patterns of brain function assessed with operational magnetic resonance imaging ( fMRI), changes in the cortical evoked response to visual stimuli that reflect the impact of meditation on aid, and alterations in bounty and synchronicity of highfrequency oscillations that probably revivify an important role in connectivity among far-flung circuitry in the brain.EXPERIMENTAL SETUP The experiments described below that beak hemodynamic changes with fMRI require a high-field-strength magnetic resonance imaging (MRI ) scanner equipt with the appropriate pulse sequences to acquire data fastly and with the necessary part optic input signal delivery devices so that visual stimuli can be presented to the issuance while he or she lays in the bore of the magnet. For the studies that measure brain electrical activity, a high-density recording system with amidst 64 and 256 electrodes on the scalp surface is used.FA MEDITATION A recent theater 4 used fMRI to interrogate the anxious correlates of FA (continued on page 172) THE end point NEUROPLASTICITY IS USED TO DESCRIBE THE BRAIN CHANGES THAT OCCUR IN RESPONSE TO EXPERIENCE. and emotional balance. Here we focus on two common styles of meditation, i. e. , focused attention (FA) meditation and open monitor (OM) meditation. FA meditation entails voluntarily focusing attention on a chosen object in a prolong fashion. OM meditation involves nonreactively monitoring the content of experience from moment to moment, primarily as a means to recognize the nature of emotional and cognitive patterns.OM meditation initially involves the use of FA training to calm the mind and reduce distractions, but as FA advances, the cultivation of the monitoring skill per se becomes the main focus of practice. The aim is to reach a state in which no unmistakable focus on a specific object is retained instead, one continues only in the monitoring state, attentive moment by moment to anything that occurs in experience. These two common styles of meditation be often ages combined, whether in a single session or oer the course of a practitioners training.These styles are found with some mutation in several meditation systems, including the 1053-5888/08/$25. 002008IEEE IEEE SIGNAL treat snip 176 kinfolk 2007 in the SPOTLIGHT y=4 continued from page 176 % T2 Accuracy Times2 Versus 1 50 40 30 20 10 0 ? 10 Novices Time1 Practitioners PZ P3b to T1 420-440 ms 0 10 1,000 F-Values ms Novices Practitioners r=? 0. 68, p=. 001 Amygdala 0. 2 0. 1 0 ? 0 . 1 ? 0. 2 10 20 30 (a) V 20 ? 20 20 ? 20 20 ? 20 20 ? 20 20 ? 20 20 ? 20 (d) 40 50 r=? 0. 64 Time2 +5? V ? 5? V ? 200 Blink No-Blink T1 T2 ?5 ? 4 ? 3 ? 2 ? 1 0 1 2 3?V T1-Elicited P3b Amplitude Time2 Versus 1 (c) (b) F3 Fc5 Cp5 F4 Fc6 Cp6 V2 500 ccc speed of light 0 Blocks 50 Resting State 100 Meditative State (e) 150 Time (s) % 100 45 0 Controls % 100 45 * * % 80 Practitioners * * * * * 40 0 on-going sign Baseline Baseline (g) Meditation State * Controls Practitioners * * 0 * 1 2 3 4 5 6 7 8 9 10 (f) 1 2 3 4 5 6 7 8 FIG1 Neuroimaging and neurodynamical correlates of FA and OM meditations. (a) Relationship between degree of meditation training (in years) and hemodynamic response in the amygdala (in blue) to distractor sounds during FA meditation in long-term Buddhist practitioners.Individual responses in the right amygdala are plotted (adapted from 4). (b) The drop-off in P3b amplitude (a brain-potential index of resource apportionment) to the first-year of two physical obj ect stimuli (T1 and T2) presented in a rapid stream of distracter stimuli after tierce months of intensifier Vipassan? meditation 5. (c) Generally, the greater the reduction in brain-resource allocation to T1 was a over time, the better able an individual became at accurately identifying T2 (adapted from 5 ). d)(e) Example of high-amplitude da Gamma activity during a form of OM meditation, nonreferential compassion meditation, in long-term Buddhist practitioners 6. (e) Time course of da Gamma (2542 Hz) activity power over the electrodes displayed in (d) during four blocks computed in a 20-s sliding window every 2 s and then averaged over electrodes. (f) Intra-individual analysis of the ratio of da Gamma to slow oscillations (413 Hz) averaged across all electrodes during compassion meditation. g) The significant fundamental interaction between group (practitioner, control) and state (initial baseline, ongoing baseline, and meditation state) for this ratio. meditation in experts and novices. The study compared FA meditation on an external visual point to a rest stop during which participants do not use meditation and are simply instructed to adopt a neutral baseline state. The meditation condition was associated with activation in multiple brain neighbourhoods implicated in monitoring (dorsolateral prefrontal cortex), engaging attention (visual cortex), and attentional orienting (e. g. , the uperior frontal sulcus, the ancillary motor area, and the intraparietal sulcus). Although this meditation-related activation pattern was generally wholeer for long-term practitioners compared to IEEE SIGNAL process MAGAZINE 172 JANUARY 2008 novices, activity in many brain areas involved in FA meditation showed an change u-shaped curve for both classes of defers. Whereas expert meditators with an average of 19,000 practice hours showed stronger activation in these areas than the novices, expert meditators with an average of 44,000 practice hours showed slight activat ion.This inverted u-shaped function resembles the learning curve associated with skill acquisition in other domains of expertise, such as language acquisition. The findings support the paper that, after all-encompassing FA meditation training, minimal effort is necessary to sustain attentional focus. serious meditators also showed less activation than novices in the amygdala during FA meditation in response to emotional sounds. Activation in this affective region jibe negatively with hours of practice in life, as shown in range 1(a).This finding whitethorn support the idea that advanced levels of concentration are associated with a significant decrease in emotionally reactive behaviors that are unfriendly with stability of concentration. Collectively, these findings support the view that attention is a trainable skill that can be enhanced through the mental practice of FA meditation. OM MEDITATION another(prenominal) study 5 recently examined the idea that OM meditation decrea ses elaborative stimulus processing in a longitudinal study using scalprecorded brain potentials and performance in an attentional blinking designate.The consequence of decreased elaborative stimulus processing is that the subject is able to better attend moment-to-moment to the stream of stimuli to which they are exposed and less likely to get stuck on any one stimulus. The attentional blink phenomenon illustrates that the information processing capacity of the brain is limited. More specifically, when two indicates T1 and T2, introduce in a rapid stream of events, are presented in keep mum temporal proximity, the second target is often not seen.This deficit is believed to upshot from competition between the two targets for limited attentional resources, i. e. , when many resources are devoted to T1 processing, too few may be available for succeeding T2 processing. The study in 5 found that three months of intensive training in Vipassan? meditation (a common style of a OM me ditation) reduced brain-resource allocation to the first target, as reflected in a smaller T1-elicited P3b, a brainpotential index of resource allocation. This is illustrated in intent 1(b), which shows the reduction in P3b amplitude.In this figure, the scalp-recorded brain potentials from electrode Pz, time-locked to T1 barrage as a function of T2 accuracy detected (no-blink) vesus not detected (blink), time (before or after three months), and group (practitioners versus novices) are shown. The scalp map shows electrode sites where this three-way interaction was significant between 420 and 440 ms. The reduction in brain-resource allocation to T1 was associated with a smaller attentional blink to T2, as shown in Figure 1(c).As participants were not engaged in formal meditation during task performance, these results provide support for the idea that one long-term effect of OM meditation may be reduction in the propensity to get stuck on a target as reflected in less elaborate stim ulus processing and the development of efficient mechanisms to engage and then disengage from target stimuli in response to task demands. Previous studies 6 of high-amplitude pattern of gamma synchrony in expert meditators during an emotional version of OM meditation support the idea that the state of OM may be best understood in name of a succession of dynamic global states.Compared to a group of novices, the title-holder practitioners self-induced higher amplitude sustained electroencephalography (EEG) gamma-band oscillations and long-distance phase synchrony, in limited over lateral fronto-parietal electrodes, while meditating. Importantly, this pattern of gamma oscillations was also sig- nificantly more(prenominal) pronounced in the baseline state of the long-term practitioners compared with controls, suggesting a switch in the default mode of the practitioners as shown in Figure 1(g).Although the nice mechanisms are not clear, such synchronizations of oscillatory neural discharges may play a crucial role in the constitution of transient networks that shuffle distributed neural processes into highly ordered cognitive and affective functions. An example of high-amplitude gamma activity during a form of OM meditation, nonreferential compassion meditation, in long-term Buddhist practitioners 6 is shown in Figure 1(d) and (e). The intra-individual analysis of the ratio of gamma to slow oscillations (413 Hz) averaged across all electrodes during compassion meditation is illustrated in Figure 1(f).The abscissa represents the subject numbers, the ordinate represents the difference in the mean ratio between the initial state and meditative state, and the black and red stars indicate that this increase is greater than two and three times, respectively, the baseline standard deviation. The significant interaction between group (practitioner, control) and state (initial baseline, ongoing baseline, and meditation state) for this ratio is shown in Figure 1(g). The relative gamma increase during meditation was higher in the postmeditation session.In the initial baseline, the relative gamma was already higher for the practitioners than the controls and correlated with the distance of the long-term practitioners meditation training through life (adapted from 6). SP CHALLENGES While SP has a bizarre opportunity to contribute to this novel effort to chart the carriage in which the brain may be transformed through the mental practice of meditation, there are several associated challenges. Among these challenges are the characterization of different signatures of brain function that distinguish among different meditation practices,IEEE SIGNAL PROCESSING MAGAZINE 173 JANUARY 2008 in the SPOTLIGHT continued the parsing of variance in brain activity that may be due to changes in peripheral physiology such as respiration, and the coincident measurement of electrical and hemodynamic signals to harness the best temporal and spatial gag law possib le. IMPACT ON BRAINCOMPUTER INTERFACES one of the interesting implications of the research on meditation and brain function is that meditation might help to reduce neural noise and so enhance signal-to-noise ratios in certain types of tasks.In contexts where brain-computer interfaces are being developed that are based upon electrical recordings of brain function, training in meditation may facilitate more rapid learning. This idea warrants systematic evaluation in the future. FUTURE WORK Ongoing and future work focuses on a few distinct directions. One of the crucial areas requiring attention is the characterization of changes in connectivity among the various brain circuits that are engaged by these practices. The development of new methods to probe different aspects of connectivity (both morphological and functional) will be extremely valuable in furthering this line of inquiry.The goal of such work is to better understand how different circuits are incorporated during meditatio n to produce the behavioral and mental changes that are said to occur as a result of such practices, including the promotion of increased well-being. AUTHORS Richard J. Davidson (emailprotected edu) is a director and Antoine Lutz (emailprotected edu) is an associate scientist, both with the Waisman Laboratory for Brain Imaging and Behavior, University of Wisconsin-Madison. REFERENCES 1 A. Berger, O. Kofman, U. Livneh, and A. Henik, Multidisciplinary perspectives on attention and the development of self-regulation, Prog.Neurobiol. , vol. 82, no. 5, pp. 256286, 2007. 2 R. A. Poldrack, neuronal systems for perceptual skill learning, Behav. Cognit. Neurosc. Rev. , vol. 1, no. 1, pp. 7683, 2002. 3 A. Lutz, J. P. Dunne, and R. J. Davidson, Meditation and the neuroscience of consciousness An introduction, in The Cambridge Handbook of Consciousness, P. D. Zelazo and E. Thompson, Eds. Cambridge, U. K. Cambridge Univ. Press, in press. 4 J. A. Brefczynski-Lewis, A. Lutz, H. S. Schaefer, D. B . Levinson, and R. J. Davidson, Neural correlates of attentional expertise in long-term meditation practitioners, Proc. Nat. Acad. Sci. , vol. 104, no. 7, pp. 1148311488. 5 H. A. Slagter, A. Lutz, L. L. Greischar, A. D. Francis, S. Nieuwenhuis, J. M. Davis, and R. J. Davidson, psychological training affects use of limited brain resources, PLoS Biol. , vol. 5, no. 6, pp. e13800010008, 2007. 6 A. Lutz, L. Greischar, N. B. Rawlings, M. Ricard, and R. J. Davidson, Long-term meditators self-induce high-amplitude synchrony during mental practice, Proc. Nat. Acad. Sci. , vol. 101, no. 46, pp. 1636916373, 2004. SP I N D I A N A U N I V E R S I T Y P U R D U E U N I V E R S I T Y F O R T WAY N E FOUNDING DIRECTOR OF THE CENTER OF EXCELLENCE IN WIRELESS confabulation RESEARCHIndiana University-Purdue University Fort Wayne (IPFW) part of Engineering invites applications and nominations for the position of insertion Director of the Center of worthiness in radio Communication Research. Candidates must possess a recognized national reputation for research justice in the field of radio communication. Masters degree postulate possession of an earned doctorate in electrical engineering or its equivalent is highly desired. Preference will be given to candidates with a strong history of applied research, patience collaboration, and experience in Department of Defense-funded projects.The initial appointment will be for a period of three years with the option for subsequent renewal based upon performance. IPFW is a regional campus of both Indiana University and Purdue University and is the largest university in northeast Indiana. Serving more than 12,000 students and offer more than 180 degree options, IPFW is a comprehensive university with a strong tradition of service to and collaboration with the region. The Department of Engineering offers B. S. degrees in electrical, computer, civil, and mechanical engineering. The M. S. egree in engineering with concentratio ns in electrical, mechanical, computer, and systems engineering will be launched during the 2007-2008 educate year. The department presently includes 16 full-time faculty members and has approximately 300 undergrad students. The Founding Director of the Center of Excellence in receiving set Communication Research shall have the following responsibilities Establish the Center of Excellence in Wireless Communication Research, emphasizing the practical application of wireless technology for the needs of the regional defense industry.Expand collaboration with industry through sponsored research. Establish a wireless laboratory to support courses in wireless communication. Develop a series of undergraduate courses that would lead to an undergraduate certificate in wireless communication. Develop and teach courses for the Master of lore in Engineering (MSE) electrical engineering concentration that would lead to a graduate certificate in wireless communication. Develop and o ffer honorable mention and non-credit professional development experiences for regional employees. Participate in IEEE 802. X standards development. arrange and host conferences on the application of wireless technology with an emphasis on defense applications and emerging commercial wireless technologies. This position offers a unique opportunity to build a Center of Excellence in Wireless Communication Research and to significantly expand industry-university collaborative research in the fields of wireless networks. IPFW offers a competitive salary and benefits package and an keen work environment. Fort Wayne is the second largest city in Indiana and is laid within several hours of Chicago, Columbus, Cincinnati, Detroit, and Indianapolis.It boasts affordable housing, a low cost of brio and a safe environment in which to raise a family. The region is home to seven major defense contractors employing over 1,800 engineers working in the fields of wireless communication, sensor ne tworks, C4, network-centric systems, and defense products. Applicants with extensive industrial kind of than university career experience will be given serious good will and are strongly encouraged to apply. Candidates demonstrating extensive contact networks within the job and governmental sectors will be preferred. To apply for this position, cheer visit our clear site at www. ipfw. obs. Applicants should submit a cover letter addressing wireless communication and DoD knowledge and experience, resume/vita, statement of research and precept experience, and the names and contact information for at least three references. The citizens committee will begin review of applications immediately and the search will remain open until the position is filled. For additional information regarding IPFW and the Department of Engineering please visit the Web sites at www. engr. ipfw. edu and www. ipfw. edu. ,3) LV DQ (TXDO 2SSRUWXQLW(TXDO $FFHVV$IILUPDWLYH $FWLRQ (PSORHU IEEE SIGNAL PROCESS ING MAGAZINE 174 JANUARY 2008