The immune system and happiness.
ABSTRACT Human ability to experience negative and positive emotions has an evolutionary perspective and the presence of feelings designed to influence behavior should thus be reflected in physiological and immune interactions. The complex interactions between the immune system and the central nervous system have been studied extensively in schizophrenia and depression. On the other hand, effects of positive human emotions, especially happiness, on physiological parameters and immunity have received very little attention. Emotions are intimately involved in the initiation or progression of cancer, HIV, cardiovascular disease, and autoimmune disorders. The specific physiological responses induced by pleasant stimuli were recently investigated with the immune and endocrine systems being monitored when pleasant stimuli such as odors and emotional pictures were presented to subjects. The results revealed that an increase in secretory immunoglobulin A and a decrease in salivary cortisol were induced by pleasant emotions. The mechanisms by which positive as opposed to negative states are instantiated in the brain and interact with the immune system are not yet understood. The present review investigates relations among physiological measures of affective style, psychological well-being, and immune function. There is data to support the hypothesis that individuals characterized by a more negative affective style poorly recruit their immune response and may be at risk for illness more so than those with a positive affective style. Future research is needed to expand our knowledge of the physiological and immune interactions of positive emotional states and their beneficial effects on health.
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ABSTRACT: The purpose of this study was to evaluate the psychometric properties of the subjective happiness scale (Ly-ubomirsky & Lepper, 1999). The objective of the first study involving 300 people from the general population was the estimated reliability (internal consistency and temporal stability) and construct validity of the scale. The second study involved 779 people, its purpose was to obtain definitive indicators of reliability and validity in samples with diverse age range. In addition, convergent and divergent validity was evaluated with instruments: Beck Depression Inventory (BDI), Big Five Questionnaire (BFI), and Dispositional Optimism Questionnaire (LOT-R). The main results of study showed an alpha of .78 and temporal stability of 61 (8 weeks apart) and a pure factorial structure. For the second study, the reliability estimation was between .73 and .87 according to the many samples studied, was found a pure factorial structure, the correlations between subjective happiness scale and instruments used to assess convergent and divergent validity were adequate, highly significant and in line with theoretical expectations. The evidence indicates adequacy of the scale for use in the assessment of this construct in the Chilean population.07/2011; 29(1):127-133. DOI:10.4067/S0718-48082011000100013
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ABSTRACT: In recent years, zoos and aquaria have intensified efforts to develop approaches and tools for assessing the welfare of populations and individual animals in their care. Advances made by welfare scientists conducting studies on exotic, farm, laboratory, and companion animals have led to the emergence of a new perspective on welfare assessment in zoos. This perspective: (1) emphasizes the importance of supplementing resource-based assessments with animal-based approaches that require measures of the behavioral and/or physical state of individual animals, (2) focuses on the subjective experiences of individual animals, and (3) considers positive affective states. We propose that the zoo community also should increase efforts to integrate measures of positive affect into both population-level studies and tools for monitoring individual well-being. For years, zoo welfare researchers have conducted trans-disciplinary, multi-institutional studies to identify risk factors associated with poor welfare. In the future, large-scale research projects, as well as epidemiological studies specifically designed to examine the patterns of welfare issues within populations, should integrate behavioral, physiological, and biological measures of good well-being (e.g. play, exploratory behaviors, measures of immunological function). While the results of population-level studies can be used to refine animal care guidelines, individual animals should be monitored to ensure that their needs are being met. Furthermore, after determining how to elicit positive affective states in individual animals, the zoo community should attempt to promote these states by offering positive experiences. We describe two strategies that zoos can currently pursue to facilitate the occurrence of positive affective states: (1) provide animals with stimulating opportunities to overcome challenges, make choices, and have some level of control over their environments, and (2) promote appropriate and beneficial keeper−animal relationships. Ultimately, we hope that as welfare researchers gain a better understanding of how to assess and promote good well-being, zoos and aquaria can apply these findings to actively strive toward achieving the best possible welfare for all animals in their care.Applied Animal Behaviour Science 08/2013; 147(3-4):247-260. DOI:10.1016/j.applanim.2013.02.004 · 1.63 Impact Factor
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ABSTRACT: Today, advances in the public health system of most countries have managed to extend notably life expectancy, however, elderly's health remain as a very serious concern. The lifelong stimulation of innate and adaptive immune systems leads to immunosenescence and, as result, to a low ability to produce immunoglobulins against pathogens but also to a low-grade chronic inflammatory state (inflammaging) that is linked to most age-related health problems, such as dementia, Alzheimer or atherosclerosis. This inflammatory state could make the host more sensitive to intestinal microbes, or vice versa , as changes in the gut microbiota composition are related to the progression of diseases and frailty in the elderly population. It was considered that gut microbiota changed during aging, with an increase of Bacteroidetes vs. Firmicutes proportion and a reduction of bifidobacterial counts, however recent studies reported a great inter-individual variation among elderly and a significant relationship between gut microbiota, diet and institution or community living. Intervention studies of probiotics and prebiotics in elderly are not very abundant, but most cases showed that Bifidobacterium populations can efficiently be stimulated with a concomitant decrease of Enterobacteria . Furthermore, also some studies demonstrated that probiotics decreased the synthesis of pro-inflammatory cytokines which are upregulated in the elderly, such as interleukin (IL)-8, IL-6 or tumour necrosis factor ?, among others, and they increased the levels of activated lymphocytes, natural killer cells, phagocytic activity and even showed a greater response to influenza vaccination. This suggests that direct manipulation of the gut microbiota may improve adaptive immune response and reduce inflammatory secretions, therefore compensating immunosenescence effects, however, there are no records of their effect on clinical symptoms or risk for disease. Those facts reveal that this is an open research field with very good scientific perspectives and above all they could bring likely improvements in the wellbeing of our seniors.Beneficial Microbes 09/2014; 5(3):235-246. · 1.50 Impact Factor