Which field of study investigates the relationship among the brain immune system and psychological factors with regard to stress related events?

Submitted: January 9th, 2021 Reviewed: July 16th, 2021 Published: August 21st, 2021

DOI: 10.5772/intechopen.99501

Abstract

Psychoneuroimmunology [PNI] is a field that has developed significantly during the last three decades; it has come to scientifically demonstrate the importance of the mind in the prevention, development and treatment of diseases. Throughout this chapter, we describe the evolution of PNI, the interaction of these systems to actively develop them, not only in adults but also in children. Similarly, it explains the influence of stress on the health of the individual and the importance of knowledge of psychoneuroimmunology to achieve the proper management of disease and quality of life. It also accounts for how psychological interventions have been proven effective and can serve as a model for researching and treating other diseases.

Keywords

• psychoneuroimmunology [PNI]
• stress
• psychological intervention
• children
• quality of life

• Margarita del Valle Chacin Fuenmayor*

  • Horley Psychology and Shineeq, Horley, United Kingdom

• Josymar Chacin de Fernandez

  • Avantem, Costa Rica

*Address all correspondence to:

1. Introduction

This chapter will describe the main clinical implications of psychoneuroimmunology and how to improve clinical evolution, quality of life and immunity of adults and children. The investigation of the multiple relationships between emotions and human cognition and health is an area of study that involves much knowledge, such as neurosciences, endocrinology, immunology, pharmacology, psychology, and psychiatry. These knowledge areas provide a partial vision to make a complete approach to the relationship between the disease, the body and the mind-brain.

The concept of health is a complex process, and it is based on a balance between biological, social and psychological factors. Engel, in 1977 [1], worked on the recognition of the intricate relationship between disease, body and mind-brain, argued that biological factors, as well as genetic factors, are not enough to explain all the phenomena that have to do with health, and that if you want to understand the origin and evolution of the disease, you must take into account the interaction of psychological and social factors in addition to genetic and biological factors; He also emphasized his criticism of the traditional biomedical model that tends to separate the mind-brain and the body; model where the body is conceived as a machine that must be repaired, leaving aside the emotions; patients are seen almost as objects, and their subjective perception is not relevant in medical evaluation and management, contributing to the dehumanized procedure of traditional medicine.

Considering the relevance around the advances in the medical field, this chapter will provide a better understanding of Psychoneuroimmunology and describe the psychological protocols developed for adult and children, which has been proven to improve clinical evolution, quality of life and immunity.

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2. Psychoneuroimmunology [PNI]

Psychoneuroimmunology [PNI] consolidates itself as an interdisciplinary research field towards the end of the 70s. It owes its name to the psychologist Robert Ader, who first introduced the term in his presidential address of the American psychosomatic society in 1980 [2]. Later this neologism was presented more formally by Ader, 1981 as the title of a landmark book of this novel discipline in which state of the art was presented, emphasizing the central nervous system’s role in the interaction of behavior and the immune system [3].

One of the newest research fields resulting from the biopsychosocial conception of health is psychoneuroimmunology [PNI], which embraces the main guideline of this model, such as the analysis of the interaction between psychosocial and biological factors in etiology, evolution and treatment of the disease. Psychoneuroimmunology is a prominent new scientific field where many sciences converge responsible for the study, analysis, understanding, and application of the complex interactions between behavior and the three systems that guarantee the human body’s homeostasis, between the nervous system, the endocrine and immune system [4].

This hybrid new discipline tries to demonstrate if the mind-brain mediates the susceptibility to illness or intervenes to recover a physical ailment, an infectious or autoimmune disease. The relationship of some psychological processes with alterations of the immune system and the interrelation of mental illnesses, mainly emotional and affective, with impaired immune function [5]. Psychoneuroimmunology provides more detailed knowledge of the intricate biological dynamics of human health. It provides novel complementary medical options or techniques and invites exploring alternative non-linear models to address the health-disease process. PNI is thus a discipline that establishes a meeting point for the different traditional health fields [2].

PNI is thus a discipline that establishes a meeting point for the different traditional health fields. Many research pieces have proven the relevance to the scientific field, which has helped to acknowledge and understand these systems’ link to improve adults and children’s health integrally.

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3. Stress and psychoneuroimmunology

Studies on the effect of stress on the immune system have allowed understanding the complex interaction between the nervous, endocrine and immune systems, which has allowed that in situations of stress, the human organism has protection mechanisms to preserve homeostasis.

In the fourteenth century, the term stress began to refer to difficult, adverse, suffering and negative situations. However, it was not until 1857, when Claude Bernard stated that environmental changes could alter the body. In 1929 the neurologist Walter Cannon recognized that stressors that cause physiological reactions resulting from threatening or adverse situations could be physical and/or emotional. Cannon also warned, later in 1932, about the importance of the person maintaining an internal balance that he called homeostasis and that in case of intense changes, a readjustment occurred through the endocrine and vegetative system [6].

Later, Hans Seyle, physiologist and physician, considered by many to be the father of the modern concept of stress, defined it in 1936 in the British journal Nature the General Adaptation Syndrome [SGA], also known as Seyle’s Law, as an automatic mechanism that is triggered by any stressful situation and that involves a set of reactions that mobilize energy reserves that implies activation of the hypothalamic-hypophysical-adrenal axis and the central nervous system, which makes the body go through three phases: alarm, resistance or adaptation of the organism and exhaustion, being able, if the threat is sufficiently severe and prolonged, even cause death [6].

When stress exceeds certain limits, the immune system is affected, numerous organs of our body, and there is a propensity for the appearance or aggravation of diseases by weakening certain immune cells that make people more susceptible to the pathogens that cause infections such as asthma, rheumatoid arthritis, herpes simplex, tuberculosis, cancer and the progression of HIV to AIDS, among others [6].

Among the consequences of chronic stress on the immune, central nervous and endocrine systems, Ortega Navas, M, 2011, highlights the following:

On the other hand, stress is also necessary and positive in our lives’ evolution at certain levels since it constitutes an essential part. Positive stress is a means of adaptation to daily situations, a means for productivity, creativity, increases alertness, improves concentration, and decision-making, making us feel safe and better prepared to face and definitively find ourselves in a more balanced situation the face of adversity and disease.

Sometimes we adults have the fantasy that children are not stressed because we see them playing or entertaining themselves in their activities, which is absolutely false since, on the contrary, the fact that the child has a high power to imagine also causes you to present abundant thoughts and that when events are not clearly explained or because of your cognitive level, you cannot interpret them clearly, it is possible that the thoughts are negative, which generates high stress and therefore also affects your immune system.

In this sense, it is essential to provide children with information, according to their age, of the events that are being generated, whether they are associated with themselves, as in the case of their health, as if it is about the people around you. It is recommended to address critical situations such as divorces, moves, bereavement and maintain close contact, with the openness to answer any question that arises at the time, to reduce the anxiety of uncertainty that is very harmful to the child.

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4. Emotions and psychoneuroimmunology

Emotions govern all the organism’s systems. The field of psychoneuroimmunology is studying how emotions are translated into chemical substances [information molecules] that can trigger chain reactions that affect internal chemistry, optimizing or weakening our functional state. Furthermore, that impacts our immune system, endocrine system, nervous system and other systems of our body. In fact, if we repress the expression of emotions, we also repress our organic functions, which in the long term translates into discomfort or diseases [6].

Research indicates that positive emotions can be enhanced and help prevent certain diseases’ appearance. What we do and what we think has positive and negative effects on our physical and emotional health. Positive emotions allow us, in addition to supporting the difficulties of an illness and facilitating its recovery by triggering a series of positive effects on our metabolism that strengthen our health, achieve, among other goals, healthy self-esteem, satisfaction for the work well done and making more effective decisions and ultimately, improve our quality of life. In fact, positive emotions also help make people more resistant to adversity and help build psychological resilience [7].

Maruso in 2009 [8], considered that emotions influence immunity and that the third revolution in medicine is precisely psychoneuroimmunoendocrinology. He insists that the mind and the body are intrinsically linked and that as a result of the mind–body interaction, reactions are triggered that affect internal chemistry, optimizing or weakening our functional state and that it is in our own hands to launch a new culture of health which implies that people are capable of maintaining and ensuring health on a physical and mental level.

Advances in psychoneuroimmunology indicate that emotional states can modify and alter health in general so that positive emotions help the person be better able to overcome diseases that may arise in life. Likewise, Ortega Navas in 2009, affirms that emotions play a vital role in health, “they are an undeniable part of our lives and are fundamental for its positive state by helping to promote healthy behaviour; on the contrary, if they are negative, they are a risk to our health, they can constitute an activating or inhibiting signal of health symptoms or a disease”.

The emotional attitude directly relates to the immune system, harmonizing better with good health than a negative attitude. A person who normally expresses happiness, good humor, love, friendship, joy and positivism is much less likely to contract a serious illness than another who, on the contrary, is angry, fearful, angry, depressed or apprehensive. In fact, when states of mind such as anger, fear, or hopelessness seize us, cortisol levels rise, which hinders the immune system’s functioning.

In sum, although emotions play a decisive role in the onset and/or course of numerous diseases, among cardiovascular, respiratory, gastrointestinal, endocrine, muscular, dermatological disorders and alterations of the immune system stand out, it is important to highlight that emotional education as a subject. The current debate is increasingly being debated in educational settings, a consequence of the need to educate people to know themselves and others better to face the challenges of their daily work better and adopt healthier lifestyles. Its purpose is to help people prevent and reduce risk behaviors through skills training or avoid possible consequences.

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5. Quality of life [QoL]

In recent times, the use of the term quality of life [QoL] has become frequent in a wide variety of contexts. Environmentalists emphasize the physical/biological environment, economists on parameters such as gross national product, doctors on symptoms, psychologists on human needs, and satisfaction. It follows that quality of life should be considered a multidisciplinary entity that is applicable and inherent to all society and the world, and its consideration by all leaders and scientists of humanity should be contemplated [9]. That is why it affirms Grau, in 1996 that the Quality-of-Life study invites us to abandon traditional positions and glimpse common sources of approach.

Almost all the authors agree that the term appears in the decade of Within Health Psychology; according to Grau, 1996, there are three large groups of problems when approaching the development of studies in Quality of Life. The first is that of its conceptual indistinctness, determined by its complex nature, the second referring to problems related to Quality of Life and the third problem inherent to the difficulties in its evaluation.

In pediatric literature, quality of life is defined as multidimensional. It includes the child’s social, physical and emotional functioning and, if necessary, of his family [10]. Quality of life questionnaires have generally been validated related to health in which information from people close to children has been used; the ability of children to report their health status has not been considered adequate [11].

For a child, it is difficult to discriminate what is quality of life, since it has no source of comparison because due to its short life and the experiences it has had, it can build its concept of life, that is why on many scales to measure the quality of life of the child takes into account the perception that family members have of well-being in the child.

In this sense, a child’s quality of life must be focused on providing a healthy environment, where they can fully develop their mental, physical and social capacities, allowing them to carry out childhood activities, reinforcing healthy beliefs that imply responsibility in their immunological condition.

5.1 Quality of life factors to consider in psychoneuroimmunology

Quality of Life is based on the construction that a person makes of their living standards according to their personal beliefs and environment, which determines their general well-being. Among the elements to consider are the following:

• Physical condition: In this aspect, the person’s body conditions, energy level, vitality and the care that the person performs to maintain it, such as exercise and daily activity, are considered.

• Lifestyle and well-being: The way the person organizes their time in a balanced way, taking into personal account spaces, free time, interpersonal relationships, academic and work activities, indicates a healthy lifestyle.

• Healthy interpersonal relationships: The way the person relates is closely linked to personal well-being, especially close relationships.

• Physical and emotional symptoms: The awareness on the part of the person of the feelings he is experiencing at the physical and mental level is vital to assess her quality of life. In this regard, it is essential to consider the manifestations of pain in the organic and emotional sphere.

• Cognitive considerations: The mental construction that the person makes of his experience, that is, the perception of it, will influence how he responds to the environment and therefore affects his quality of life.

• Introspection, self-esteem and self-care: Intrapersonal communication, which implies communication with me, being compassionate and with a motivating dialog that reinforces self-esteem, is vital. Also accompanied by self-love that implies effective self-care in all areas.

• Sleep quality: it is considered relevant to validate problems falling asleep, interrupted sleep, insomnia, among others.

• Image and Sexuality: Self-image, added to the interest in sexual relations, desire and level of satisfaction, are factors to consider.

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6. Psychological interventions based on psychoneuroimmunology in adults

Psychological interventions based on psychoneuroimmunology must be structured, taking into account:

1. Conviction in the patient of the mind–body relationship.

2. Knowledge of the immune system’s primary authors and how it is related to the endocrine system and the nervous system.

3. Awareness in the patient that his mental and physical condition is linked to internal factors.

4. Identification of harmful behavioral patterns that must be modified to improve the quality of life.

6.1 Some techniques used in psychoneuroimmunology

6.1.1 Cognitive-behavioral psychotherapy

In this therapy applied to psychoneuroimmunology, the way of thinking on the immune response is explained to the person. A variety of cognitive strategies have helped identify the unhealthy beliefs that affect the individual’s health condition. In general, the following process is followed:

• Identify the unhealthy belief

• Recognize the connections between thought - emotion - behavior.

• Examine the evidence that is for or against your thoughts.

• Correct distorted thoughts

• Replace cognitions with healthy beliefs.

6.1.2 Relaxation techniques

Relaxation techniques commonly used in psychoneuroimmunology usually include muscle relaxation and deep breathing to decrease neurovegetative activation. The training is the same as those used in clinical contexts, only adapting the procedure to health conditions.

6.1.3 Guided imagery techniques

The body does not discriminate between what we imagine and the actual events, which is why people who carry out a treatment based on psychoneuroimmunology must become aware of the power of their mind, and the care they must have at the time to worry in advance or imagine catastrophic events that alter their physical conditions.

Guided imagination in PNI includes 2 phases. Initially, the patient is guided through a relaxation process, and then he is induced to imagine the activation of his nervous, endocrine and immune systems to regulate his disease. This imagination can be general or specific according to his illness.

6.1.4 Psychoeducation

• Information about the disease:

In PNI, the patient must know all the details related to his disease. For example, if he has a tumor in any part of the body, it is essential that he can see the exams, know where it is located, its size, shape, texture, everything that allows him to imagine it or even draw it later.

• Treatment information:

In psychoneuroimmunology, the patient has an active role in his clinical condition and recovery of health; that is why he must know all the treatment details, the approximate time that he will receive them and the side effects. It is relevant that the patient can mentally potentiate or reject these treatments; that is why it is necessary to verify the distracted or catastrophic thoughts that can alter him emotionally and affect the immune response.

In children, it is very important to foster a collaborative attitude towards treatment, which stems from the understanding that some treatments, although painful, are promoting their health. Also, strengthening communication with their parents and health professionals.

• Information on the Immune System

The patient is required to recognize the main authors of the immune system to develop greater control over his physical symptoms and disease.

The content provided implies understanding the defense system, represented by white blood cells, and its function is to defend the person from viruses, bacteria, and any invading agent, such as tumor cells.

In psychoeducation, the different types of cells must be present, and their characteristics and general functions are explained according to the age group and cognitive level. Among the actors that stand out are T Lymphocyte, B Lymphocyte, Macrophage, Natural Killer Cell or NK and Neutrophil Polymorphonuclear.

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7. Psychoneuroimmunology research in adults

There are several reasons to investigate whether a psychological intervention, in patients or healthy subjects, alters immunity: 1] Because it is possible to know if there is a causal relationship between psychological factors and the functioning of the immune system 2] because the improvement of the immunity obtained after the psychological intervention would be an added benefit [eg. Some stressors can cause a decrease in some forms of immunity. The psychological intervention would reduce stress and increase the multidisciplinary treatment of patients affected by organic diseases [5].

In this sense, any psychological variable can influence the appearance or the course and outcome of a certain disease in which the immune system is involved. As the psychological determinants that influence behavior can come directly from the CNS or indirectly through the stress response [hormonal mechanisms], any change in behavior that is associated with personality characteristics or coping styles in emergencies [stressful], as well as negative emotional states, could affect the immune system [for example, people who smoke or overeat when stressed or people who generate more stress than necessary in everyday situations by evaluating them exaggeratedly threatening]. It also happens that, on some occasions, individuals see a threat where there is none [or they exaggerate it], resulting in the acquisition of a phobia; either they do not have adequate coping resources at a given moment [they do not know how to solve problems], or they have wrong ideas about how the world should work [irrational ideas or cognitive distortions] [10].

This can be evidence in a in work carried out by Antoni in 2003 [12], through a 10-week group program based on cognitive stress control and relaxation strategies, the results show that there are effects of psychological intervention on mood, as well as neuroendocrine changes in the HHC, HHG [Hypothalamic–Pituitary–Gonadal] axis as well as in the hormones of the Sympathetic Nervous System and the state of the Immune System in people infected with HIV. The changes produced by the effects of relaxation and cognitive coping strategies, and social support can mediate mood changes. In turn, these changes affect the regulation of adrenal hormones evaluated through changes in urinary cortisol, norepinephrine, and testosterone levels. As suggested by Antoni, the changes in these hormones as a result of the intervention could also explain, in part, the short-term changes in IgG antibodies and the longer-term changes in CD4 lymphocytes.

Similarly, Robinson in 2002 [13] showed encouraging results with an 8-week program to reduce stress in people infected with HIV. Subjects who received this treatment showed increased activity in the killer [NK] cells and their number. The same measurements were taken three months after completing the intervention, noting that the increases in NK cells and decreases in tension, anger or depression also remained, thus showing the subjects a much-improved state of mind.

In any case, the psychological influence of the mind on the body, and more specifically in the field of PNI since the mid-70s, have been treated from multidisciplinary approaches that include medicine, psychology, sociology, social work and even religion [3].

For this reason, and as far as psychologists are concerned, psychotherapies are usually directed towards two final objectives: to reduce or eliminate levels of stress and/or depression. Although stressors can be physical or psychological, the disparity between them is a mere illusion when it comes to the emission of a stress response [3]. Therefore, any treatment aimed at eliminating or reducing the stress response will be favoring the improvement of depression, this being, in this way, considered a dependent variable.

How an individual interprets and responds to a certain stressor determines its reaction [flight, freeze or flight] and the immune system’s response and disease behaviors [14]. Therefore, any intervention from health psychology, designed to modulate stress, provides problem-solving strategies, identifies both phobic stimuli and real or potentially dangerous stimuli, adopts healthy behaviors, and interprets life events from a perspective adaptive [not a perfectionist or tremendous], will walk in the direction sought.

It has been scientifically proven that there are significant decreases in hormones related to stress, such as thyroxine or GH, decreases in Cortisol, THS, and prolactin have also been described during relaxation. Visualization produces increases in IgA levels in saliva. Decreases in the sensitivity of beta-adrenergic receptors measured in circulating lymphocytes have also been described without variations in the number of receptors or catecholamines’ plasma concentration [15].

It has also been demonstrated that loneliness, social support, stressful situations such as exams, personality variables, etc., have been studied. The treatments carried out have shown certain effectiveness, these being mainly: Visualization techniques, Directed Imagination, Relaxation, Cognitive-Behavioral Stress Control Techniques, as well as Meditation, Shamanic Techniques, Prayers, etc. Any of these techniques can be useful if it is practised with the necessary rigor, whatever the psychological approach used. However, relaxation produces physiological states that, combined with the representation of images [imagination], can become so-called meditation techniques, positive visualization, directed imagination, etc. That is to say, positive emotion, in this case pleasant, would be the combination of the body state with a mental representation in the form of an image and thought [15].

Furthermore, Bower in 2003 [16], developed a handy tool that achieved more significant control of emotions and cognitive processes called guided imagination. To develop desired changes in behavior, guided imagery can be used to relieve muscle tension, reduce or eliminate pain, and facilitate the process of managing stressful situations through behavioral change. In this technique, it is important to describe the positive physiological and psychological effects of imagining scenes.

Understanding the communications between the brain and the immune system at their most intimate levels will also help health professionals believe in their patients when they tell them that their beliefs in the recovery process, hope, and laughter make you feel good.

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8. Psychoneuroimmunology in children

There are very few studies on interventions based on psychoneuroimmunology [PNI] in pediatric patients. Studies reported that inappropriate clinical settings, knowledge of PNI could improve outcomes for pediatric surgical patients. Additionally, parents who receive these same services may also experience better psychological health, allowing them to be more available and prepared to support their children’s recovery [17].

Castes in 1999 [18], carried out an investigation in the Isla de Coche, Venezuela, entitled: “Clinical, immunological changes associated with a psychosocial support program based on psychoneuroimmunology in asthmatic children”, the authors state that anatomical evidence is presented, physiological and functional that demonstrate the interaction between the central nervous system [CNS], the endocrine system and the immune system. Likewise, it is shown that this communication is bidirectional, and the scientific bases that establish communication between the immune system and the CNS are provided. Likewise, the relationship between stress and the immune response is pointed out. We also present the results of our group that show that a psychosocial intervention based on psychoneuroimmunology [PNI] produced a significant decrease [p