Os efeitos da meditação à luz da investigação científica em Psicologia: revisão de literatura / Los efectos de la meditación a la luz de la investigación científica en Psicología: revisión de literatura / Meditation effects on scientific research in Psychology: literature review

A meditação, descrita como uma prática de auto-regulação do corpo e da mente, caracteriza-se por um conjunto de técnicas que treinam a focalização da atenção. Também conhecida como treinamento mental, essa prática constitui uma técnica capaz de produzir efeitos psicossomáticos. Este artigo apresenta a revisão de algumas evidências acerca dos benefícios da meditação e do seu papel na aplicação clínica. Inúmeros estudos vêm mostrando a sua eficácia, que está especialmente relacionada à diminuição dos sintomas ligados ao estresse e à ansiedade. Além disso, as pesquisas revelam que essa prática pode produzir efeitos de curta e longa duração que podem afetar positivamente as funções cognitivas e afetivas. Discutemse aspectos relacionados às definições e às particularidades de cada técnica e aos contextos aos quais pode estar atrelada. Apesar do crescente acúmulo de evidências sobre a relação entre meditação e saúde física e mental, ainda são necessárias mais investigações.(AU)

Meditation, described as a practice of body and mind self-regulation, is characterized by a set of techniques that train the focalization of attention. Also known as a mental training, this practice characterizes a technique capable of producing psychosomatic effects. This paper presents a revision of some evidence on the benefits of meditation and its role for clinical application. A great deal of research has shown its efficacy, especially concerning its association with the reduction of symptoms related to stress and anxiety. Besides that, research has indicated that this practice can produce short and long term effects, affecting positively the cognitive and affective functions. We discuss the aspects related to the definitions and particularities of each technique and the contexts to which meditation can be linked to. Despite growing evidence on the relationship between meditation and physical and mental health, it is still necessary to carry out further investigation.(AU)

La meditación, descrita como una práctica de autorregulación del cuerpo y de la mente, se caracteriza por un conjunto de técnicas que entrenan la focalización de la atención. También conocida como entrenamiento mental, esa práctica constituye una técnica capaz de producir efectos psicosomáticos. Este artículo presenta la revisión de algunas evidencias acerca de los beneficios de la meditación y de su papel en la aplicación clínica. Numerosos estudios vienen mostrando su eficacia, que está especialmente relacionada a la disminución de los síntomas relacionados al estrés y a la ansiedad. Además, las pesquisas revelan que esa práctica puede producir efectos de corta y larga duración que pueden afectar positivamente las funciones cognoscitivas y afectivas. Se discuten aspectos relacionados a las definiciones y a las particularidades de cada técnica y a los contextos a los cuales puede estar unida. A pesar de la creciente acumulación de evidencias sobre la relación entre meditación y salud física y mental, aún son necesarias más averiguaciones.(AU)

Alzheimer's disease, amnestic mild cognitive impairment, and age-associated memory impairment: current understanding and progress toward integrative prevention.

Alzheimer's disease, AD, is the most common form of dementia. AD initially targets memory and progressively destroys the mind. The brain atrophies as the neocortex suffers neuronal, synaptic, and dendritic losses, and the hallmark amyloid plaques and neurofibrillary tangles proliferate. Pharmacological management, at best, is palliative and transiently effective, with marked adverse effects. Certain nutrients intrinsic to human biochemistry (orthomolecules) match or exceed pharmacological drug benefits in double-blind, randomized, controlled trials, with superior safety. Early intervention is feasible because its heritability is typically minimal and pathological deterioration is detectable years prior to diagnosis. The syndrome amnestic mild cognitive impairment exhibits AD pathology and to date has frustrated attempts at intervention. The condition age-associated memory impairment is a nonpathological extreme of normal brain aging, but with less severe cognitive impairment than amnestic mild cognitive impairment. Age-associated memory impairment is a feasible target for early intervention against AD, beginning with the modifiable AD risk factors - smoking, hypertension, homocysteine, type 2 diabetes, insulin resistance, and obesity. Stress reduction, avoidance of toxins, and mental and physical exercise are important aspects of prevention. The diet should emphasize omega-3 fatty acids docosahexaenoic acid and eicosapentaenoic acid; flavonoids and other antioxidant nutrients; and B vitamins, especially folate, B6 and B12. Dietary supplementation is best focused on those proven from randomized, controlled trials: the phospholipids phosphatidylserine and glycerophosphocholine, the energy nutrient acetyl-L-carnitine, vitamins C and E, and other antioxidants. A comprehensive integrative strategy initiated early in cognitive decline is the most pragmatic approach to controlling progression to Alzheimer's disease.

Preventive effect of a traditional herbal medicine, Hochu-ekki-to, on immunosuppression induced by surgical stress.

PURPOSE: To examine the effect of preoperative administering of a Japanese traditional herbal medicine, Hochu-ekki-to (TJ-41), on immunosuppression induced by surgical stress in patients with gastrointestinal malignancies. METHODS: To monitor the immune functions, the mitochondrial membrane potential (MMP) and natural killer (NK) cell activity prior to and following operation were measured in peripheral blood lymphocytes (PBL) in patients with (n = 20) or without (n = 27) the preoperative administering of TJ-41 for 7 days. The plasma catecholamine and interleukin (IL)-6 levels were also analyzed prior to and following the operation. RESULTS: The numbers of MMP-high CD56-positive cells (NK cells) and NK cell activities in the TJ-41-treated group were significantly higher than those in the control group (P = 0.026 and P = 0.037, respectively). An elevation of plasma noradrenaline and IL-6 following surgery was also inhibited by the preoperative administering of TJ-41 (P = 0.023 and P = 0.039, respectively). A positive correlation between MMP-high CD56-positive cell numbers and NK cell activity in PBL treated with carbonyl cyanide m-chlorophenyl hydrazone (CCCP) in vitro suggested that MMP measurement in CD56-positive cells can serve as a convenient alternative to evaluate the NK cell activity. CONCLUSION: Our findings suggest that the preoperative administering of TJ-41 prevents surgical stress-induced immunosuppression by maintaining the NK cell activity and inhibiting the elevation of stress mediators.

Stress responses in adult cattle due to surgical dehorning using three different types of anaesthesia.

Dehorning adult cattle is a surgical procedure causing distress of varying intensities that can be reflected in behavioural changes and alterations in plasma cortisol levels. Stress responses during the dehorning process were evaluated in 18 Red Pied cows. The cows were divided into 3 groups of six and kept in tie-stall housing. Those in the first group were dehorned under general anaesthesia (GA) induced by intravenous administration of xylazine and ketamine. The second group was dehorned under sedation and local anaesthesia (SLA) induced by intramuscular administration of xylazine and local anaesthesia with lidocaine. The third group was dehorned under local anaesthesia (LA) with lidocaine. Dehorning was performed with a foetotomy wire. Blood samples were taken 0.5 h before dehorning to determine cortisol levels, and, by means of a central venous catheter inserted into the jugular vein, during surgery at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7 and 8 h post-surgery. Concurrently, occurrence of stress behaviours was assessed. Cortisol levels were measured by enzyme immunoassay (EIA). The lowest mean peak levels of plasma cortisol (82.53 +/- 6.04 nmol l(-1)), the most rapid return of plasma cortisol levels to baseline values (1.92 +/- 1.11 h), and the lowest occurrence of stress behaviours (2.38 +/- 5.83%) were noted in the SLA group. The highest mean peak levels plasma cortisol (113.86 +/- 25.65 nmol l(-1)), the slowest return of plasma cortisol levels to baseline values (3.83 +/- 2.18 h) and the most frequent occurrence of stress behaviours (65.48 +/- 28.72%) were observed in the LA group. There were significant differences between the SLA and LA groups in peak plasma cortisol levels (p = 0.011) and in occurrence of stress behaviours (p = 0.003). Sedation induced by intramuscular administration of xylazine in conjunction with local anaesthesia with lidocaine is considered the most suitable method of anaesthesia when dehorning adult cattle. Local anaesthesia with lidocaine alone was least suitable.

Overture for growth hormone: requiem for interleukin-6?

BACKGROUND: Music has been used for therapeutic purposes since the beginning of cultural history. However, despite numerous descriptions of beneficial effects, the precise mechanisms by which music may improve human well-being remain unclear. METHODS: We conducted a randomized study in ten critically ill patients to identify mechanisms of music-induced relaxation using a special selection of slow movements of Mozart's piano sonatas. These sonatas were analyzed for compositional elements of relaxation. We measured circulatory variables, brain electrical activity, serum levels of stress hormones and cytokines, requirements for sedative drugs, and level of sedation before and at the end of a 1-hr therapeutic session. RESULTS: Compared with controls, we found that music application significantly reduced the amount of sedative drugs needed to achieve a comparable degree of sedation. Simultaneously, among those receiving the music intervention, plasma concentrations of growth hormone increased, whereas those of interleukin-6 and epinephrine decreased. The reduction in systemic stress hormone levels was associated with a significantly lower blood pressure and heart rate. CONCLUSION: Based on the effects of slow movements of Mozart's piano sonatas, we propose a neurohumoral pathway by which music might exert its sedative action. This model includes an interaction of the hypothalamic-pituitary axis with the adrenal medulla via mediators of the unspecific immune system

Protective effect of Triphala on cold stress-induced behavioral and biochemical abnormalities in rats.

Stress is one of the basic factors in the etiology of number of diseases. Cold-stress occurs when the surrounding temperature drops below 18 degrees C, the body may not be able to warm itself, and hence serious cold-related illnesses, permanent tissue damage and death may results. The present study was aimed to investigate the effect of Triphala (Terminalia chebula, Terminalia belerica and Emblica officinalis) against the cold stress-induced alterations in the behavioral and biochemical abnormalities in four different groups (saline control, Triphala, cold-stress and Triphala with cold-stress) of Wistar strain albino rats. In this study cold-stress (8 degrees C for 16 h/d/15 days) was applied and the oxidative stress was assessed by measuring the extent of lipid peroxidation (LPO) and the changes in corticosterone levels. Upon exposure to the cold-stress, a significant (P<0.05) increase in immobilization with decrease in rearing, grooming, and ambulation behavior was seen in open field. Following cold-exposure, significant increase in the LPO and corticosterone levels was observed. Oral administration of Triphala (1 g/kg/animal body weight) for 48 days significantly prevented these cold stress-induced behavioral and biochemical abnormalities in albino rats. The results of this study suggest that Triphala supplementation can be regarded as a protective drug against stress.

Assessment of slow-breathing relaxation technique in acute stressful tasks using a multipurpose non-invasive beat-by-beat cardiovascular monitoring system.

Recently, several studies revealed that daily slow-breathing exercise lowered blood pressure and increased baroreflex sensitivity. With this interesting finding, we have been contemplating to design a compact breath-controllable device for relaxation to stress reaction during daily living for home as well as ambulatory use, as a final goal, towards reduction of cognitive hemodynamic disorders, hypertension, and acute stress-induced hemodynamic disorders. The present study thereby describes, as a first step, to design a prototype system combining a compact multipurpose non-invasive beat-by-beat cardiovascular monitor developed previously with a wrist-type vibrator to make a respiration rhythm, and to assess an effect of slow-breathing relaxation on the cardiovascular hemodynamics in response to acute stressful conditions. The cardiovascular hemodynamic monitor can measure beat-by-beat systolic (SBP), mean (MBP) and diastolic (DBP) pressure in a finger based on the volume-compensation method, cardiac output (CO) by the electrical admittance method and the other hemodynamic-related parameters (e.g., total peripheral resistance (TPR=MBP/CO), heart rate (HR), respiratory rate, pulse wave velocity, etc.). The wrist-type vibrator can give various breathing rhythms quietly to a subject using a small vibration motor. The stressful tasks loaded to healthy volunteers (3 males, 23-34 yrs.) in the experiments were cold pressor and arithmetic ones as a representative of daily passive and active coping tasks, respectively, under conditions with (respiratory rate of 6 1/min) and without breath control.. The results showed that the slow-breathing technique could have a significant effect on improvement of the hemodynamic changes following the acute stressful tasks, especially in the passive coping task.

Prenatal stress generates deficits in rat social behavior: Reversal by oxytocin.

Neurodevelopmental changes induced by environmental stress exposure play a significant but poorly defined role in the etiology of schizophrenia. Exposure of pregnant female rats to a series of unpredictable stresses during the final week of pregnancy generates behavioral deficits and molecular changes in the offspring similar to those observed in schizophrenic individuals. We used this rat prenatal stress preparation to investigate social withdrawal behaviors that may have relevance to the negative symptoms of schizophrenia. The cumulative time adult male offspring of stress-exposed pregnant female rats actively interacted with a weight-matched, same-sex peer was decreased approximately 76% relative to non-stress exposed control rats. Prenatal stress exposure also diminished the quality of the social interaction behavior indicative of reduced social drive. Analysis of the oxytocinergic system in the prenatally stressed male rats revealed significantly less oxytocin mRNA in the paraventricular nucleus and increased oxytocin receptor binding in the central amygdala. Moreover, oxytocin, but not vasopressin, administration into the central amygdala reversed the social incompetence of the prenatally stressed rats without increasing behavior in non-stressed control animals. In addition, cross-fostering pups from prenatally stressed mothers to non-stressed mothers failed to improve the social deficit of the prenatally stressed male offspring. Two behavioral assays designed to measure anxiety did not differentiate the prenatally stressed rats from non-stressed controls. These data indicate that prenatal stress may be an etiologically appropriate animal model for some aspects of schizophrenic social withdrawal. Furthermore, unpredictable prenatal stress exposure selectively degrades social interaction behaviors without increasing anxiety measures.

A pilot study to test the effects of art-making classes for family caregivers of patients with cancer.

PURPOSE/OBJECTIVES: To test the effects of an art-making class (AMC) on reducing anxiety and stress among family caregivers of patients with cancer. DESIGN: A pretest and post-test quasi-experimental design. SETTING: A residential care facility near tertiary treatment centers in the southeastern United States. SAMPLE: The convenience sample of 69 family caregivers was aged 18-81 years (X = 48 years) and predominantly Catholic. Most had at least a high school education. Two-thirds were daughters, wives, or mothers of patients with cancer. METHODS: Participants completed a demographic data survey and a Beck Anxiety Inventory (BAI). Researchers collected a saliva sample from each participant to measure salivary cortisol, which indicates stress levels. Following pretesting, a two-hour AMC was delivered. Post-tests included a repeat BAI and a second saliva sample. MAIN RESEARCH VARIABLES: Anxiety and stress. FINDINGS: Anxiety was significantly reduced after AMC. Stress was reduced. CONCLUSIONS: The AMC appeared to reduce anxiety and stress. The addition of a control group and replication with larger numbers are suggested. The physiologic cortisol measure corroborated BAI findings but was difficult to obtain from some cultural groups and was expensive to analyze. IMPLICATIONS FOR NURSING: Family caregivers may benefit from participation in art-making interventions. Nurses should continue to investigate the use of creative approaches to promote holistic care.

The effects of an intensive lifestyle modification program on sleep and stress disorders.

BACKGROUND: To determine if a lifestyle change program can modify behavior to reduce sleep and stress disorders. METHODS: Analyses are based on 2,624 individuals aged 30 to 80 years from the Rockford, Illinois metropolitan area who completed a lifestyle evaluation at baseline and again after four weeks, following participation in a 40-hour educational course given over a four-week period. Participants receive instruction on the importance of making better lifestyle choices related to making long-term improvements in nutrition and physical activity and they learn ways to improve sleep and reduce stress in their lives. RESULTS: Significant percent decreases were observed in the number experiencing selected sleep or stress disorders from baseline to four weeks later for "sleeps restlessly" (-59%), "suffers from insomnia" (-64%), "feels under pressure" (-37%), "easily emotionally upset" (-52%), and "feels fearful or depressed" (-61%). Experiencing a selected sleep or stress disorder after four weeks among those who had the disorder at baseline was significantly more likely in those not physically active and/or not having lowered their BMI after four weeks. Changes in alcohol consumption and smoking did not significantly contribute to changes in the disorders. Those who failed to lower their coffee/tea use after four weeks were significantly more likely to have a sleep disorder and be easily emotionally upset. CONCLUSIONS: Changes in lifestyle behaviors after attending an educational program significantly reduced sleep and stress disorders in as little as four weeks, primarily explained by decreasing BMI and/or increasing exercise.

A comparison of paracetamol, ibuprofen or their combination for pain relief following extractions in children under general anaesthesia: a randomized controlled trial.

OBJECTIVE: This study was designed to compare the effectiveness of different oral analgesics for relieving pain and distress in children following the extraction of teeth under general anaesthesia (GA). The analgesics included paracetamol alone, ibuprofen alone, and paracetamol and ibuprofen in combination. METHODS: Two hundred and one subjects were randomly allocated to one of four groups. Forty-seven children were included in the ibuprofen alone (5 mg kg(-1)) group, 51 in the paracetamol/ibuprofen combination (15/5 mg kg(-1)) group, 48 in the high-dose paracetamol (20 mg kg(-1)) group, and 55 children were included in the usual-dose paracetamol (15 mg kg(-1)) group (control group). Evaluation of distress for children was made immediately pre-operatively, on recovery from anaesthesia and again after 15 min by using a five-point face scale. Furthermore, each child was observed immediately postoperatively and 15 min postoperatively for signs of pain using the Children's Hospital of Eastern Ontario Pain Scale. RESULTS: There were significant decreases in the mean pain and distress scores for both the ibuprofen alone and paracetamol/ibuprofen combination groups compared to the control group (usual-dose paracetamol) at 15 min postoperatively. CONCLUSIONS: This study provides evidence to support the oral administration of ibuprofen alone or in combination with paracetamol for postoperative analgesia in children who are having teeth extracted under GA.

Prophylactic role for complementary and alternative medicine in perinatal programming of adult health.

BACKGROUND: The health status of an individual in adulthood is proposed to be determined by events occurring in the prenatal and early postnatal period. A common early life event proven to have long lasting effects on the developing fetus is stress, including pain. Exposure of fetal and neonatal infants to repetitive psychological (e.g., maternal stress) or physiological (e.g., pain, infection, and noise) stress during this period is proposed to alter mechanisms involved in the regulation of stress, immunological maturation, pain perception, and cognition. Such changes, which persist into adulthood, may occur via alterations in the development of the hypothalamic-pituitary-adrenal (HPA) axis. This process is typically referred to as 'perinatal programming'. Ontogenic alterations in the development of the HPA-axis have been related to a number of adult pathologies such as cardiovascular disease, type 2 diabetes, asthma, as well as psychopathologies such as anxiety and depression. OBJECTIVE: In this review, the effectiveness of complementary and alternative medicine (CAM), such as music, dietary supplements, massage and aromatherapy, in reducing perinatal stress in mothers and infants is examined. An emphasis is placed on these therapies as preventative measures which may be of value to individuals at risk of developing disease profiles associated with the consequences of adverse perinatal programming. The widening interest in perinatal programming and CAM suggests the potential for CAM to become a valuable tool in offsetting negative adult health outcomes resulting from perinatal programming associated with adverse gestational early life environments.

A minimal stress model for the assessment of electroacupuncture analgesia in rats under halothane.

The use of anesthetics in acupuncture analgesia is controversial. We evaluate a steady-state light anesthesia model to test whether minimal stress manipulation and reliable measurement of analgesia could be simultaneously achieved during electroacupuncture (EA) in animals. A series of experiments were performed. Firstly, EA compliance and tail-flick latencies (TFL) were compared in rats under 0.1%, 0.3%, 0.5%, 0.7%, or 1.1% halothane for 120min. Under 0.5% halothane, TFL were then measured in groups receiving EA at intensity of 3, 10 or 20 volt (V), 1 or 2mg/kg morphine, 20V EA plus naloxone, or control. Subsequently, the effect of EA on formalin-induced hyperalgesia was tested and c-fos expression in the spinal dorsal horn was analyzed. Rats exhibited profound irritable behaviors and highly variable TFL under 0.1% or 0.3% halothane, as well as a time-dependent increase of TFL under 0.7% or 1.1% halothane. TFL remained constant at 0.5% halothane, and needle insertion and electrical stimulation were well tolerated. Under 0.5% halothane, EA increased TFL and suppressed formalin-induced hyperalgesia in an intensity-dependent and naloxone-reversible manner. EA of 20V prolonged TFL by 74%, suppressed formalin-induced hyperalgesia by 32.6% and decreased c-fos expression by 29.7% at the superficial and deep dorsal horn with statistically significant difference. In conclusion, 0.5% halothane provides a steady-state anesthetic level which enables the humane application of EA stimulus with the least interference on analgesic assessment. This condition serves as a minimal stress EA model in animals devoid of stress-induced analgesia while maintaining physiological and biochemical response in the experiment.

Board-invited review: recent advances in management of highly stressed, newly received feedlot cattle.

Morbidity and mortality from bovine respiratory disease (BRD) and associated losses in performance and carcass merit continue to plague the beef cattle industry. Several viral/bacterial agents are responsible for BRD, and interactions occur among the agents. Viral agents often predispose animals to bacterial infections, and Mannheimia haemolytica is the most frequently isolated organism in cattle with BRD. Laboratory tests are available to characterize organisms causing BRD using easily obtained nasal swab samples. Testing for persistent infection with bovine viral diarrhea virus can be done by a 2-stage technique using PCR and immunohistochemistry. Preconditioning programs that include preweaning viral vaccination programs along with castration could have a significant influence on decreasing BRD in the cattle feeding industry. Metaphylactic antibiotic programs continue to be effective; however, antibiotic resistance is a public concern, and additional management options (e.g., direct-fed microbials or other compounds with antimicrobial properties) deserve attention. Diets with an increased energy concentration achieved by decreasing the dietary roughage concentration may slightly increase the rate of BRD morbidity; however, these diets also increase ADG, DMI, and G:F compared with lower-energy, greater-roughage diets. The extent to which performance and BRD morbidity are affected by dietary protein concentration needs further study, but low and high protein concentrations should probably be avoided. Several trace minerals (e.g., Cu, Se, and Zn) affect immune function, but the effects of supplementation on performance and immune function in model challenge systems and in field studies are equivocal. Adding vitamin E to receiving diets at pharmacological levels (e.g., >1,000 IU x animal(-1) x day(-1)) seems beneficial for decreasing BRD morbidity, but it has little effect on performance. Given the limited ability to consistently modify immune function and BRD morbidity through dietary manipulations, we recommend that the diets for newly received cattle be formulated to adjust nutrient concentrations for low feed intake and to provide optimal performance during the receiving period.

Consumer perceptions of nutrition and health claims.

The number of food products containing extra or reduced levels of specific ingredients (e.g. extra calcium) that bring particular health benefits (e.g. stronger bones) is still increasing. Nutrition- and health-related (NH) claims promoting these ingredient levels and their health benefit differ in terms of the (legal) strength with which the claim is brought forward and the specific wording of the claim, both of which may differ between countries. Using a large-scale cross-national internet-based survey in Italy (n=1566), Germany (n=1620), UK (n=1560) and US (n=1621), the purpose of the study described here is to investigate consumer perceptions of NH food product claims, across different countries. NH claims are systematically varied as a function of six health benefits (cardiovascular disease, stress, infections, fatigue, overweight and concentration) and five claim types (content, structure-function, product, disease-risk reduction and marketing claim). The general results indicate that consumer perceptions differ substantially by country and benefit being claimed but much less by the claim type. Implications of these findings are being discussed.