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Friday, July 14, 2023

Erikson's stages of psychosocial development

Erikson's stages of psychosocial development, as articulated in the second half of the 20th century by Erik Erikson in collaboration with Joan Erikson, is a comprehensive psychoanalytic theory that identifies a series of eight stages that a healthy developing individual should pass through from infancy to late adulthood.

According to Erikson's theory the results from each stage, whether positive or negative, influences the results of succeeding stages. Erikson published a book called Childhood and Society in 1950 that made his research well known on the eight stages of psychosocial development. Erikson was originally influenced by Sigmund Freud's psychosexual stages of development. He began by working with Freud's theories specifically, but as he began to dive deeper into biopsychosocial development and how other environmental factors affect human development, he soon progressed past Freud's theories and developed his own ideas. Erikson developed different substantial ways to create a theory about lifespan he theorized about the nature of personality development as it unfolds from birth through old age or death. He argued that the social experience was valuable throughout our life to each stage that can be recognizable by a conflict specifically as we encounter between the psychological needs and the surroundings of the social environment.

Erikson's stage theory characterizes an individual advancing through the eight life stages as a function of negotiating their biological and sociocultural forces. The two conflicting forces each have a psychosocial crisis which characterizes the eight stages. If an individual does indeed successfully reconcile these forces (favoring the first mentioned attribute in the crisis), they emerge from the stage with the corresponding virtue. For example, if an infant enters into the toddler stage (autonomy vs. shame and doubt) with more trust than mistrust, they carry the virtue of hope into the remaining life stages. The stage challenges that are not successfully overcome may be expected to return as problems in the future. However, mastery of a stage is not required to advance to the next stage. In one study, subjects showed significant development as a result of organized activities.

Stages

Approximate Age Virtues Psychosocial crisis Significant relationship Existential question
Events
Infancy

Under 1 year

Hope Trust vs. Mistrust Mother Can I trust the world? Feeding, abandonment
Toddlerhood

1–2 years

Will Autonomy vs. Shame/Doubt Parents Is it okay to be me? Toilet training, clothing themselves
Early childhood

3–6 years

Purpose Initiative vs. Guilt Family Is it okay for me to do, move, and act? Exploring, using tools or making art
Late childhood

7–10 years

Competence Industry vs. Inferiority Neighbors, School Can I make it in the world of people and things? School, sports
Adolescence

11–19 years

Fidelity Identity vs. Role Confusion Peers, Role Model Who am I? Who can I be? Social relationships
Early adulthood

20–44 years

Love Intimacy vs. Isolation Friends, Partners Can I unite myself with another person? Romantic relationships
Middle adulthood

45–64 years

Care Generativity vs. Stagnation Household, Workmates Can I make my life count? Work, parenthood
Late adulthood

65 and above

Wisdom Ego Integrity vs. Despair Humankind, My kind Is it okay to have been me? Reflection on life

Psychological periodization of stages of human development

Hope: trust vs. mistrust (oral-sensory, infancy, under 1 year)

  • Existential Question: Can I Trust the World?

The first stage of Erik Erikson's theory centers around the infant's basic needs being met by the parents or caregiver and how this interaction leads to trust or mistrust. Trust as defined by Erikson is "an essential trustfulness of others as well as a fundamental sense of one's own trustworthiness." The infant depends on the parents, especially the mother, for sustenance and comfort. Infants will often use methods such as pointing to indicate their interests or desires to their parents or caregivers. The child's relative understanding of the world and society comes from the parents and their interaction with the child. Children first learn to trust their parents or a caregiver. If the parents expose their child to warmth, security, and dependable affection, the infant's view of the world will be one of trust. As the child learns to trust the world around them, they also acquire the virtue of hope. Should parents fail to provide a secure environment and to meet the child's basic needs; a sense of mistrust will result. Development of mistrust can later lead to feelings of frustration, suspicion, withdrawal, and a lack of confidence.

According to Erik Erikson, the major developmental task in infancy is to learn whether or not other people, especially primary caregivers, regularly satisfy basic needs. If caregivers are consistent sources of food, comfort, and affection, an infant learns trust — that others are dependable and reliable. If they are neglectful, or perhaps even abusive, the infant instead learns mistrust — that the world is an undependable, unpredictable, and possibly a dangerous place. Having some experience with mistrust allows the infant to gain an understanding of what constitutes dangerous situations later in life. However, infants and toddlers should not be subjected to prolonged situations of mistrust. This causes children to be ill adjusted later in life and see life with a cautious and careful outlook, which can be detrimental later in their life. In this stage, the child's most important needs are to feel safe, comforted, and well cared for.

This stage is where a child learns an attachment style to their caregiver. The attachment style the child develops can affect their relationships through the rest of their life. For example, if the infant is hungry, will it be fed? If their diaper got soiled, would anybody change it? If they're sad, will they be comforted? The infant's mind would tell if the world is a trustworthy place with trustworthy people. Infants need protection and support from the familiar adult; otherwise, they will most likely not survive. This concept was studied more by Bowlby and Ainsworth in their attachment theory which is consistent with Erikson's research.

Will: autonomy vs. shame/doubt (muscular-anal, toddlerhood, 1–2 years)

  • Existential Question: Is It Okay to Be Me?

As the child gains control over eliminative functions and motor abilities, they begin to explore their surroundings. Parents still provide a strong base of security from which the child can venture out to assert their will. The parents' patience and encouragement help to foster autonomy in the child. During early childhood, the child will start to have learning tasks and skills that instill personal responsibility, which allows the children to make choices that could help them develop a sense of autonomy and confidence. Children at this age like to explore the world around them and they are constantly learning about their environment. Caution must be taken at this age while children may explore things that are dangerous to their health and safety.

At this age, children develop their first interests. For example, a child who enjoys music may like to play with the radio. Children who enjoy the outdoors may be interested in animals and plants. Highly restrictive parents are more likely to instill in the child a sense of doubt, and reluctance to try new and challenging opportunities. As the child gains increased muscular coordination and mobility, toddlers become capable of satisfying some of their own needs. They begin to feed themselves, wash and dress themselves, and use the bathroom.

If caregivers encourage self-sufficient behavior, toddlers will develop a sense of autonomy—a sense of being able to handle many problems on their own. On the contrary, there is the possibility that the caregiver can demand too much too soon. This will likely lead the child to develop shame and doubt in their ability to handle problems. This shame and doubt could also come as a result of a caregiver ridiculing a child's early performance attempts. There is definitely a delicate balance to be had with autonomy. If the child receives too much autonomy, they have the potential to grow up with little concern for rules or regulations. It is worth noting that this could also increase the likelihood of injury. Conversely, if the parents exert too much control over them, the child can grow up to be more rebellious and impulsive. The abilities of the child are limited. 

Purpose: initiative vs. guilt (locomotor-genital, early childhood, 3–6 years)

  • Existential Question: Is it Okay for Me to Do, Move, and Act?

Initiative adds to autonomy the quality of planning, undertaking, and attacking a task for the sake of just being active and on the move. The child is learning to master the world around them, learning basic skills and principles of physics. Things fall down, not up, round things roll. They learn how to zip and tie, count and speak with ease. At this stage, the child wants to begin and complete their own actions for a purpose. Guilt is a confusing new emotion. They may feel guilty over things that logically should not cause guilt. They may feel guilt when this initiative does not produce desired results.

The development of courage and independence are what set preschoolers, ages three to six years of age, apart from other age groups. Young children in this category face the psychological crisis of initiative versus guilt. This includes learning how to face complexities of planning and developing a sense of judgment. During this stage, the child learns to take initiative and prepares for leadership roles, and to achieve goals. Activities sought out by a child in this stage may include risk-taking behaviors, such as crossing a street alone or riding a bike without a helmet; both these examples involve self-limits. The child may also develop negative behaviors as they learn to take initiative. These negative behaviors, such as throwing objects, hitting, or yelling, can be a result of the child feeling frustrated after not being able to achieve a goal as planned.

Preschoolers are increasingly able to accomplish tasks on their own and can explore new areas. With this growing independence comes many choices about activities to be pursued. Sometimes children take on projects they can readily accomplish, but at other times they undertake projects that are beyond their capabilities or that interfere with other people's plans and activities. If parents and preschool teachers encourage and support children's efforts, while also helping them make realistic and appropriate choices, children develop initiative—independence in planning and undertaking activities. But if instead, adults discourage the pursuit of independent activities or dismiss them as silly and bothersome, children develop guilt about their needs and desires.

Competence: industry vs. inferiority (latency, late childhood, 7–10 years)

  • Existential Question: Can I Make it in the World of People and Things?

The aim of this stage is to bring a productive situation to completion which gradually supersedes the whims and wishes of play. The fundamentals of technology are developed. The failure to master trust, autonomy, and industrious skills may cause the child to doubt their future, leading to shame, guilt, and the experience of defeat and inferiority.

The child must deal with demands to learn new skills or risk a sense of inferiority, failure, and incompetence. In doing so, children are able to start contributing to society and making a difference in the world. They become more aware of themselves and how competent, or not, they are.

"Children at this age are becoming more aware of themselves as individuals." They work hard at "being responsible, being good and doing it right." They are now more reasonable to share and cooperate. Allen and Marotz (2003) also list some perceptual cognitive developmental traits specific for this age group. Children grasp the concepts of space and time in more logical, practical ways. They gain a better understanding of cause and effect, and of calendar time. At this stage, children are eager to learn and accomplish more complex skills: reading, writing, telling time. They also get to form moral values, recognize cultural and individual differences and are able to manage most of their personal needs and grooming with minimal assistance. At this stage, children might express their independence by talking back and being disobedient and rebellious.

Erikson viewed the elementary school years as critical for the development of self-confidence. Ideally, elementary school provides many opportunities to achieve the recognition of teachers, parents and peers by producing things—drawing pictures, solving addition problems, writing sentences, and so on. If children are encouraged to make and do things and are then praised for their accomplishments, they begin to demonstrate industry by being diligent, persevering at tasks until completed, and putting work before pleasure. If children are instead ridiculed or punished for their efforts or if they find they are incapable of meeting their teachers' and parents' expectations, they develop feelings of inferiority about their capabilities.

Children also begin to make relationships with others around them. Being social is especially important for this stage. It helps school aged children become either more or less confident about themselves and their abilities. Also, during this age, children also begin to migrate into their own social groups. Depending on the child's "group", the child will have more or less self confidence.

At this age, children start recognizing their special talents and continue to discover interests as their education improves. They may begin to choose to do more activities to pursue that interest, such as joining a sport if they know they have athletic ability, or joining the band if they are good at music. If not allowed to discover their own talents in their own time, they will develop a sense of lack of motivation, low self-esteem, and lethargy. They may become "couch potatoes" if they are not allowed to develop interests.

Fidelity: identity vs. role confusion (adolescence, 11-19 years)

  • Existential Question: Who Am I and What Can I Be?

The adolescent is newly concerned with how they appear to others. Superego identity is the accrued confidence that the outer sameness and continuity prepared in the future are matched by the sameness and continuity of one's meaning for oneself, as evidenced in the promise of a career. The ability to settle on a school or occupational identity is pleasant. In later stages of adolescence, the child develops a sense of sexual identity. Adolescents become curious about the roles they will play in the adult world as they transition from childhood to adulthood. Initially, they are apt to experience some role confusion—mixed ideas and feelings about the specific ways in which they will fit into society—and may experiment with a variety of behaviors and activities (e.g. tinkering with cars, baby-sitting for neighbors, affiliating with certain political or religious groups). Eventually, Erikson proposed, most adolescents achieve a sense of identity regarding who they are and where their lives are headed.

The teenager must achieve identity in occupation, gender roles, politics, and, in some cultures, religion. This is not always easy, however. The teenager must seek to find their place in this world and to find out how they can contribute to the world.

Erikson is credited with coining the term "identity crisis". He describes identity crisis as a critical part of development in which an adolescent or youth develops a sense of self. Identity crisis involves the integration of the physical self, personality, potential roles and occupations. It is influenced by culture and historical trends. This stage is necessary for the successful development of future stages. Each stage that came before and that follows has its own 'crisis', but even more so now, for this marks the transition from childhood to adulthood. This passage is necessary because "Throughout infancy and childhood, a person forms many identifications. But the need for identity in youth is not met by these." This turning point in human development seems to be the reconciliation between 'the person one has come to be' and 'the person society expects one to become'. This emerging sense of self will be established by 'forging' past experiences with anticipations of the future. In relation to the eight life stages as a whole, the fifth stage corresponds to the crossroads:

What is unique about the stage of Identity, is that it is a special sort of synthesis of earlier stages and a special sort of anticipation of later ones. Youth has a certain unique quality in a person's life; it is a bridge between childhood and adulthood. Youth is a time of radical change—the great body changes accompanying puberty, the ability of the mind to search one's own intentions and the intentions of others, the suddenly sharpened awareness of the roles society has offered for later life.

Adolescents "are confronted by the need to re-establish boundaries for themselves and to do this in the face of an often potentially hostile world". This is often challenging since commitments are being asked for before particular identity roles have formed. At this point, one is in a state of 'identity confusion', but society normally makes allowances for youth to "find themselves", and this state is called 'the moratorium':

The problem of adolescence is one of role confusion—a reluctance to commit which may haunt a person into his mature years. Given the right conditions—and Erikson believes these are essentially having enough space and time, a psychosocial moratorium, when a person can freely experiment and explore—what may emerge is a firm sense of identity, an emotional and deep awareness of who they are.

As in other stages, bio-psycho-social forces are at work. No matter how one has been raised, one's personal ideologies are now chosen for oneself. Often, this leads to conflict with adults over religious and political orientations. Another area where teenagers are deciding for themselves is their career choice, and often parents want to have a decisive say in that role. If society is too insistent, the teenager will acquiesce to external wishes, effectively forcing him or her to ‘foreclose' on experimentation and, therefore, true self-discovery. Once someone settles on a worldview and vocation, will they be able to integrate this aspect of self-definition into a diverse society? According to Erikson, when an adolescent has balanced both perspectives of "What have I got?" and "What am I going to do with it?" they have established their identity:

Dependent on this stage is the ego quality of fidelity—the ability to sustain loyalties freely pledged in spite of the inevitable contradictions and confusions of value systems. (Italics in original)

Leaving past childhood and facing the unknown of adulthood is a component of adolescence. Another characteristic of this stage is moratorium which tends to end as adulthood begins. Given that the next stage (Intimacy) is often characterized by marriage, many are tempted to cap off the fifth stage at 20 years of age. However, these age ranges are actually quite fluid, especially for the achievement of identity, since it may take many years to become grounded, to identify the object of one's fidelity, to feel that one has "come of age". In the biographies Young Man Luther and Gandhi's Truth, Erikson determined that their crises ended at ages 25 and 30, respectively:

Erikson does note that the time of Identity crisis for persons of genius is frequently prolonged. He further notes that in our industrial society, identity formation tends to be long, because it takes us so long to gain the skills needed for adulthood's tasks in our technological world. So… there is not exact time span in which to find oneself. It does not happen automatically at eighteen or at twenty-one. A very approximate rule of thumb for our society would put the end somewhere in one's twenties.

Love: intimacy vs. isolation (early adulthood, 20–45 years)

  • Existential Question: Can I Love?

The Intimacy versus Isolation conflict occurs following adolescence. At the start of this stage, identity versus role confusion is coming to an end, although it still lingers at the foundation of the stage. The stage doesn't always involve a romantic relationship but includes the strong bonds with others being formed. Young adults are still eager to blend their identities with those of their friends because they want to fit in. Erikson believes that people are sometimes isolated due to intimacy. People are afraid of rejections such as being turned down or their partners breaking up with them. Human beings are familiar with pain, and to some people, rejection is so painful that their egos cannot bear it. Erikson also argues that distantiation occurs with intimacy. Distantiation is the desire to isolate or destroy things that may be dangerous to one's own ideals or life. This can occur if a person has their intimate relationship invaded by outsiders.

Once people have established their identities, they are ready to make long-term commitments to others. They become capable of forming intimate, reciprocal relationships (e.g. through close friendships or marriage) and willingly make the sacrifices and compromises that such relationships require. Those in more advanced stages of identity development are often associated with greater success pertaining to intimacy formation. If people cannot form these intimate relationships—perhaps because of their own needs—then a sense of isolation may result, thereby arousing feelings of darkness and angst.

Erickson’s documentation of his theory spends time considering intimacy between 2 people. The main conflict is whether an individual is willing to give up themselves up to someone else. As suggested in the previous paragraphs, it seems that it could be very valuable for someone at this stage to let go of some of their fears in order to gain a solid relationship with another person. Erickson discusses the differences of his theory as compared to Freud’s theory of psychosexual development. Freud tended to focus more on sexual gratification without deep personal relationships being involved. Erikson’s proposal suggests that there is more to intimacy than sexual gratification. There is value in the deep bonds that can be shared between two people socially. It is worth noting that Erikson, in his writing, does still discuss and see the value of sexual relations within a socially intimate relationship.

Care: generativity vs. stagnation (middle adulthood, 45–64 years)

  • Existential Question: Can I Make My Life Count?

Generativity is the concern of guiding the next generation. Socially-valued work and disciplines are expressions of generativity.

The adult stage of generativity has broad application to family, relationships, work, and society. "Generativity, then is primarily the concern in establishing and guiding the next generation... the concept is meant to include... productivity and creativity."

During middle age, the primary developmental task is one of contributing to society and helping to guide future generations. When a person makes a contribution during this period, perhaps by raising a family or working toward the betterment of society, a sense of generativity—a sense of productivity and accomplishment—results. In contrast, a person who is self-centered and unable or unwilling to help society move forward develops a feeling of stagnation—a dissatisfaction with the relative lack of productivity. The virtue that is related with this stage is care. In contrary, the maladaptive virtue is rejectivity.

As shared in the quote above, productivity and creativity are announced as being related to generativity. Despite this relation, Erikson hopes that those two words don’t take away from the main message[36]. That message being that generativity is focusing on helping other people. Our society can sometimes hyperfixate on the idea that children need parents. Erikson shares and reinforces another view. Adults need children. The effort that is given to the children can help the adult become more mature. On top of that, as an adult is generative to youth, it can influence the children to return the favor when they grow up.

Central tasks of middle adulthood
  • Express love through more than sexual contacts.
  • Maintain healthy life patterns.
  • Develop a sense of unity with mate.
  • Help growing and grown children to be responsible adults.
  • Relinquish central role in lives of grown children.
  • Accept children's mates and friends.
  • Create a comfortable home.
  • Be proud of accomplishments of self and mate/spouse.
  • Reverse roles with aging parents.
  • Achieve mature, civic and social responsibility.
  • Adjust to physical changes of middle age.
  • Use leisure time creatively.

Wisdom: ego integrity vs. despair (late adulthood, 65 years and above)

  • Existential Question: Is it Okay to Have Been Me?

As people grow older and become senior citizens, they tend to slow down their productivity and explore life as a retired person. Factors such as leisure activities and family involvement play a significant role in the life of a retiree and their adjustment to living without having to perform specific duties each day pertaining to their career. Even during this stage of adulthood, however, they are still developing. The association between aging and retirement can bring about a reappearance of bipolar tensions of earlier stages in Erikson's model, meaning that aspects of previous life stages can reactivate because of the onset of aging and retirement. Development at this stage also includes periods of reevaluation regarding life satisfaction, sustainment of active involvement, and developing a sense of health maintenance. Developmental conflicts may arise in this stage, but psychological growth in earlier stages can help significantly in resolving these conflicts.

It is during this time that they contemplate their accomplishments and evaluate the person that they have become. They are able to develop integrity if they see themselves as leading a successful life. Those that have developed integrity perceive that their lives have meaning. They tend to feel generally satisfied and accept themselves and others. As they near the end of their lives, they are more likely to be at peace about death. If they see their life as unproductive or feel that they did not accomplish their life goals, they become dissatisfied with life and develop despair. This can often lead to feelings of depression and hopelessness. They may also feel that life is unfair and be fearful of dying.

During this time there may be a renewal in interest in many things. This is believed to occur because the individuals in this time of life strive to be autonomous. As their bodies and minds start to deteriorate, they want to find a sense of balance. They will cling to their autonomy so that they will not need to be reliant on others for everything. Erikson explains that it is also important for adults in this stage to maintain relationships with others of different ages in order to develop integrity.

The final developmental task is retrospection: people look back on their lives and accomplishments. Practices such as narrative therapy can help individuals reinterpret their minds pertaining to their past and allow them to focus on the brighter aspects of their lives. They develop feelings of contentment and integrity if they believe that they have led a happy and productive life. If they look back on a life of disappointments and unachieved goals, they may instead develop a sense of despair.

This stage can occur out of the sequence when an individual feels they are near the end of their life (such as when receiving a terminal disease diagnosis).

When looking back on life, a person should hope to find both meaning and order. There are ways to alter or buoy one’s perspective during this stage. Altering or buoying one’s view could bring them closer to ego integrity. With that being said, it is better that a person has already carried out a life with meaning and order prior to beginning this stage.

Erikson ties this stage of development back into the first stage, trust vs mistrust. As shared by Erikson, the Webster dictionary once claimed that trust is “the assured reliance on another’s integrity”. One’s integrity could influence someone else’s trust. If a person at the end of their life fears death, then it could influence children to possibly fear life. If an adult is able to overcome any fears of death, then it can reinforce children to not be afraid of the life ahead of them.

Ninth stage

  • Psychosocial Crises: All first eight stages in reverse quotient order

Joan Erikson, who married and collaborated with Erik Erikson, added a ninth stage in The Life Cycle Completed: Extended Version. Living in the ninth stage, she wrote, "old age in one's eighties and nineties brings with it new demands, reevaluations, and daily difficulties". Addressing these new challenges requires "designating a new ninth stage". Erikson was ninety-three years old when she wrote about the ninth stage.

Joan Erikson showed that all the eight stages "are relevant and recurring in the ninth stage". In the ninth stage, the psychosocial crises of the eight stages are faced again, but with the quotient order reversed. For example, in the first stage (infancy), the psychosocial crisis was "Trust vs. Mistrust" with Trust being the "syntonic quotient" and Mistrust being the "dystonic". Joan Erikson applies the earlier psychosocial crises to the ninth stage as follows:

"Basic Mistrust vs. Trust: Hope"
In the ninth stage, "elders are forced to mistrust their own capabilities" because one's "body inevitably weakens". Yet, Joan Erikson asserts that "while there is light, there is hope" for a "bright light and revelation".

"Shame and Doubt vs. Autonomy: Will"
Ninth stage elders face the "shame of lost control" and doubt "their autonomy over their own bodies". So it is that "shame and doubt challenge cherished autonomy".

"Inferiority vs. Industry: Competence"
Industry as a "driving force" that elders once had is gone in the ninth stage. Being incompetent "because of aging is belittling" and makes elders "like unhappy small children of great age".

"Identity confusion vs. Identity: Fidelity"
Elders experience confusion about their "existential identity" in the ninth stage and "a real uncertainty about status and role".

"Isolation vs. Intimacy: Love"
In the ninth stage, the "years of intimacy and love" are often replaced by "isolation and deprivation". Relationships become "overshadowed by new incapacities and dependencies".

"Stagnation vs. Generativity: Care"
The generativity in the seventh stage of "work and family relationships", if it goes satisfactorily, is "a wonderful time to be alive". In one's eighties and nineties, there is less energy for generativity or caretaking. Thus, "a sense of stagnation may well take over".

"Despair and Disgust vs. Integrity: Wisdom"
Integrity imposes "a serious demand on the senses of elders". Wisdom requires capacities that ninth stage elders "do not usually have". The eighth stage includes retrospection that can evoke a "degree of disgust and despair". In the ninth stage, introspection is replaced by the attention demanded to one's "loss of capacities and disintegration".

Living in the ninth stage, Joan Erikson expressed confidence that the psychosocial crisis of the ninth stage can be met as in the first stage with the "basic trust" with which "we are blessed".

Development of post-Freudian theory

Erikson was a student of Anna Freud, the daughter of Sigmund Freud, whose psychoanalytic theory and psychosexual stages contributed to the basic outline of the eight stages, at least those concerned with childhood. Namely, the first four of Erikson's life stages correspond to Freud's oral, anal, phallic, and latency phases, respectively. Also, the fifth stage of adolescence is said to parallel the genital stage in psychosexual development:

Although the first three phases are linked to those of the Freudian theory, it can be seen that they are conceived along very different lines. Emphasis is not so much on sexual modes and their consequences, but on the ego qualities which emerge from each of the stages. There is an attempt also to link the sequence of individual development to the broader context of society.

Erikson saw a dynamic at work throughout life, one that did not stop at adolescence. He also viewed the life stages as a cycle: the end of one generation was the beginning of the next. Seen in its social context, the life stages were linear for an individual but circular for societal development:

In Freud's view, development is largely complete by adolescence. In contrast, one of Freud's students, Erik Erikson (1902–1994) believed that development continues throughout life. Erikson took the foundation laid by Freud and extended it through adulthood and into late life.

Criticism

One major criticism of Erikson's theory of psychosocial development is that it primarily describes the development of European or American males. Erikson's theory may be questioned as to whether his stages must be regarded as sequential, and only occurring within the age ranges he suggests. There is debate as to whether people only search for identity during the adolescent years or if one stage needs to happen before other stages can be completed. However, Erikson states that each of these processes occur throughout the lifetime in one form or another, and he emphasizes these "phases" only because it is at these times that the conflicts become most prominent.

Most empirical research into Erikson has related to his views on adolescence and attempts to establish identity. His theoretical approach was studied and supported, particularly regarding adolescence, by James E. Marcia. Marcia's work has distinguished different forms of identity, and there is some empirical evidence that those people who form the most coherent self-concept in adolescence are those who are most able to make intimate attachments in early adulthood. This supports the part of Eriksonian theory, that suggests that those best equipped to resolve the crisis of early adulthood are those who have most successfully resolved the crisis of adolescence.

Another criticism of Erikson's theory of psychosocial development is that he does not go into detail about what causes these stages of development or how they are resolved. There is little information stated about the experiences that result in how a person develops at each stage. Just as there are vague details about the causes of each seory does not outline the necessary steps to resolve conflict in order to enter the next stage.

Acromegaly

From Wikipedia, the free encyclopedia
 
Acromegaly
Lower jaw showing the classic spacing of teeth due to acromegaly.
Pronunciation
SpecialtyEndocrinology
SymptomsEnlargement of the hands, feet, forehead, jaw, and nose, thicker skin, deepening of the voice
ComplicationsType 2 diabetes, sleep apnea, high blood pressure, high cholesterol, heart problems, particularly enlargement of the heart (cardiomyopathy), osteoarthritis, spinal cord compression or fractures, increased risk of cancerous tumors, precancerous growths (polyps) on the lining of the colon.
Usual onsetMiddle age
CausesExcess growth hormone
Diagnostic methodBlood tests, medical imaging
Differential diagnosisPachydermoperiostosis
TreatmentSurgery, medications, radiation therapy
MedicationSomatostatin analogue, GH receptor antagonist
PrognosisUsually normal (with treatment), 10 year shorter life expectancy (no treatment)
Frequency3 per 50,000 people

Acromegaly is a disorder that results in excess growth of certain parts of the human body. It is caused by excess growth hormone (GH) after the growth plates have closed. The initial symptom is typically enlargement of the hands and feet. There may also be an enlargement of the forehead, jaw, and nose. Other symptoms may include joint pain, thicker skin, deepening of the voice, headaches, and problems with vision. Complications of the disease may include type 2 diabetes, sleep apnea, and high blood pressure.

Cause and diagnosis

Acromegaly is usually caused by the pituitary gland producing excess growth hormone. In more than 95% of cases the excess production is due to a benign tumor, known as a pituitary adenoma. The condition is not inherited. Acromegaly is rarely due to a tumor in another part of the body. Diagnosis is by measuring growth hormone after a person has consumed a glucose solution, or by measuring insulin-like growth factor I in the blood. After diagnosis, medical imaging of the pituitary is carried out to determine if an adenoma is present. If excess growth hormone is produced during childhood, the result is the condition gigantism rather than acromegaly, and it is characterized by excessive height.

Treatment

Treatment options include surgery to remove the tumor, medications, and radiation therapy. Surgery is usually the preferred treatment; the smaller the tumor, the more likely surgery will be curative. If surgery is contraindicated or not curative, somatostatin analogues or GH receptor antagonists may be used. Radiation therapy may be used if neither surgery nor medications are completely effective. Without treatment, life expectancy is reduced by 10 years; with treatment, life expectancy is not reduced.

Epidemiology, history, and culture

Acromegaly affects about 3 per 50,000 people. It is most commonly diagnosed in middle age. Males and females are affected with equal frequency. It was first described in the medical literature by Nicolas Saucerotte in 1772. The term is from the Greek ἄκρον (akron) meaning "extremity", and μέγα (mega) meaning "large".

Signs and symptoms

Compared with the hand of an unaffected person (left), the hand of a person with acromegaly (right) is enlarged, with fingers that are widened, thickened and stubby, and with thicker soft tissue
 
Mandibular overgrowth leads to prognathism, maxillary widening, teeth spacing and malocclusion
 
Brow ridge and forehead protrusion remaining after tumor removal and tissue swelling eliminated

Features that may result from a high level of GH or expanding tumor include:

Complications

Causes

Pituitary adenoma

About 98% of cases of acromegaly are due to the overproduction of growth hormone by a benign tumor of the pituitary gland called an adenoma. These tumors produce excessive growth hormone and compress surrounding brain tissues as they grow larger. In some cases, they may compress the optic nerves. Expansion of the tumor may cause headaches and visual disturbances. In addition, compression of the surrounding normal pituitary tissue can alter production of other hormones, leading to changes in menstruation and breast discharge in women and impotence in men because of reduced testosterone production.

A marked variation in rates of GH production and the aggressiveness of the tumor occurs. Some adenomas grow slowly and symptoms of GH excess are often not noticed for many years. Other adenomas grow rapidly and invade surrounding brain areas or the sinuses, which are located near the pituitary. In general, younger people tend to have more aggressive tumors.

Most pituitary tumors arise spontaneously and are not genetically inherited. Many pituitary tumors arise from a genetic alteration in a single pituitary cell that leads to increased cell division and tumor formation. This genetic change, or mutation, is not present at birth but is acquired during life. The mutation occurs in a gene that regulates the transmission of chemical signals within pituitary cells; it permanently switches on the signal that tells the cell to divide and secrete growth hormones. The events within the cell that cause disordered pituitary cell growth and GH oversecretion currently are the subject of intensive research.

Pituitary adenomas and diffuse somatomammotroph hyperplasia may result from somatic mutations activating GNAS, which may be acquired or associated with McCune-Albright syndrome.

Other tumors

In a few people, acromegaly is caused not by pituitary tumors, but by tumors of the pancreas, lungs, and adrenal glands. These tumors also lead to an excess of GH, either because they produce GH themselves or, more frequently, because they produce GHRH (growth hormone-releasing hormone), the hormone that stimulates the pituitary to make GH. In these people, the excess GHRH can be measured in the blood and establishes that the cause of the acromegaly is not due to a pituitary defect. When these nonpituitary tumors are surgically removed, GH levels fall and the symptoms of acromegaly improve.

In people with GHRH-producing, non-pituitary tumors, the pituitary still may be enlarged and may be mistaken for a tumor. Therefore, it is important that physicians carefully analyze all "pituitary tumors" removed from people with acromegaly so as to not overlook the possibility that a tumor elsewhere in the body is causing the disorder.

Diagnosis

Frequent serum GH measurements in normal subjects (left panel) demonstrate that GH can fluctuate between undetectable levels most of the time interspersed with peaks of up to 30 μg/L (90 mIU/L); in acromegaly (right panel) GH hypersecretion is continuous with no undetectable levels.

If acromegaly is suspected, medical laboratory investigations followed by medical imaging , if the lab tests are positive, confirms or rules out the presence of this condition.

IGF1 provides the most sensitive lab test for the diagnosis of acromegaly, and a GH suppression test following an oral glucose load, which is a very specific lab test, will confirm the diagnosis following a positive screening test for IGF1. A single value of the GH is not useful in view of its pulsatility (levels in the blood vary greatly even in healthy individuals).

Magnetic resonance image of a pituitary macroadenoma that caused acromegaly with compression of the optic chiasm

GH levels taken 2 hours after a 75- or 100-gram glucose tolerance test are helpful in the diagnosis: GH levels are suppressed below 1 μg/L in normal people, and levels higher than this cutoff are confirmatory of acromegaly.

Other pituitary hormones must be assessed to address the secretory effects of the tumor, as well as the mass effect of the tumor on the normal pituitary gland. They include thyroid stimulating hormone (TSH), gonadotropic hormones (FSH, LH), adrenocorticotropic hormone, and prolactin.

An MRI of the brain focusing on the sella turcica after gadolinium administration allows for clear delineation of the pituitary and the hypothalamus and the location of the tumor. A number of other overgrowth syndromes can result in similar problems.

Differential diagnosis

Pseudoacromegaly is a condition with the usual acromegaloid features, but without an increase in growth hormone and IGF-1. It is frequently associated with insulin resistance. Cases have been reported due to minoxidil at an unusually high dose. It can also be caused by a selective post receptor defect of insulin signalling, leading to the impairment of metabolic, but preservation of mitogenic, signalling.

Treatment

Site of action of the different therapeutic tools in acromegaly. Surgery, radiotherapy, somatostatin analogues and dopamine agonists act at the level of the pituitary adenoma, while GH receptor antagonists act in the periphery by blocking the growth hormone receptor and thus impairing the effects of GH on the different tissues.

The goals of treatment are to reduce GH production to normal levels thereby reversing or ameliorating the signs and symptoms of acromegaly, to relieve the pressure that the growing pituitary tumor exerts on the surrounding brain areas, and to preserve normal pituitary function. Currently, treatment options include surgical removal of the tumor, drug therapy, and radiation therapy of the pituitary.

Medications

Somatostatin analogues

The primary current medical treatment of acromegaly is to use somatostatin analogues – octreotide (Sandostatin) or lanreotide (Somatuline). These somatostatin analogues are synthetic forms of a brain hormone, somatostatin, which stops GH production. The long-acting forms of these drugs must be injected every 2 to 4 weeks for effective treatment. Most people with acromegaly respond to this medication. In many people with acromegaly, GH levels fall within one hour and headaches improve within minutes after the injection. Octreotide and lanreotide are effective for long-term treatment. Octreotide and lanreotide have also been used successfully to treat people with acromegaly caused by non-pituitary tumors.

Somatostatin analogues are also sometimes used to shrink large tumors before surgery.

Because octreotide inhibits gastrointestinal and pancreatic function, long-term use causes digestive problems such as loose stools, nausea, and gas in one third of people. In addition, approximately 25 percent of people with acromegaly develop gallstones, which are usually asymptomatic. In some cases, octreotide treatment can cause diabetes due to the fact that somatostatin and its analogues can inhibit the release of insulin. With an aggressive adenoma that is not able to be operated on, there may be a resistance to octreotide and in which case a second generation SSA, pasireotide, may be used for tumor control. However, insulin and glucose levels should be carefully monitored as pasireotide has been associated with hyperglycemia by reducing insulin secretion.

Dopamine agonists

For those who are unresponsive to somatostatin analogues, or for whom they are otherwise contraindicated, it is possible to treat using one of the dopamine agonists, bromocriptine or cabergoline. As tablets rather than injections, they cost considerably less. These drugs can also be used as an adjunct to somatostatin analogue therapy. They are most effective in those whose pituitary tumours cosecrete prolactin. Side effects of these dopamine agonists include gastrointestinal upset, nausea, vomiting, light-headedness when standing, and nasal congestion. These side effects can be reduced or eliminated if medication is started at a very low dose at bedtime, taken with food, and gradually increased to the full therapeutic dose. Bromocriptine lowers GH and IGF-1 levels and reduces tumor size in fewer than half of people with acromegaly. Some people report improvement in their symptoms although their GH and IGF-1 levels still are elevated.

Growth hormone receptor antagonists

The latest development in the medical treatment of acromegaly is the use of growth hormone receptor antagonists. The only available member of this family is pegvisomant (Somavert). By blocking the action of the endogenous growth hormone molecules, this compound is able to control the disease activity of acromegaly in virtually everyone with acromegaly. Pegvisomant has to be administered subcutaneously by daily injections. Combinations of long-acting somatostatin analogues and weekly injections of pegvisomant seem to be equally effective as daily injections of pegvisomant.

Surgery

Surgical removal of the pituitary tumor is usually effective in lowering growth hormone levels. Two surgical procedures are available for use. The first is endonasal transsphenoidal surgery, which involves the surgeon reaching the pituitary through an incision in the nasal cavity wall. The wall is reached by passing through the nostrils with microsurgical instruments. The second method is transsphenoidal surgery during which an incision is made into the gum beneath the upper lip. Further incisions are made to cut through the septum to reach the nasal cavity, where the pituitary is located. Endonasal transsphenoidal surgery is a less invasive procedure with a shorter recovery time than the older method of transsphenoidal surgery, and the likelihood of removing the entire tumor is greater with reduced side effects. Consequently, endonasal transsphenoidal surgery is the more common surgical choice.

These procedures normally relieve the pressure on the surrounding brain regions and lead to a lowering of GH levels. Surgery is most successful in people with blood GH levels below 40 ng/ml before the operation and with pituitary tumors no larger than 10 mm in diameter. Success depends on the skill and experience of the surgeon. The success rate also depends on what level of GH is defined as a cure. The best measure of surgical success is the normalization of GH and IGF-1 levels. Ideally, GH should be less than 2 ng/ml after an oral glucose load. A review of GH levels in 1,360 people worldwide immediately after surgery revealed that 60% had random GH levels below 5 ng/ml. Complications of surgery may include cerebrospinal fluid leaks, meningitis, or damage to the surrounding normal pituitary tissue, requiring lifelong pituitary hormone replacement.

Even when surgery is successful and hormone levels return to normal, people must be carefully monitored for years for possible recurrence. More commonly, hormone levels may improve, but not return completely to normal. These people may then require additional treatment, usually with medications.

Radiation therapy

Radiation therapy has been used both as a primary treatment and combined with surgery or drugs. It is usually reserved for people who have tumor remaining after surgery. These people often also receive medication to lower GH levels. Radiation therapy is given in divided doses over four to six weeks. This treatment lowers GH levels by about 50 percent over 2 to 5 years. People monitored for more than 5 years show significant further improvement. Radiation therapy causes a gradual loss of production of other pituitary hormones with time. Loss of vision and brain injury, which have been reported, are very rare complications of radiation treatments.

Selection of treatment

The initial treatment chosen should be individualized depending on the person's characteristics, such as age and tumor size. If the tumor has not yet invaded surrounding brain tissues, removal of the pituitary adenoma by an experienced neurosurgeon is usually the first choice. After surgery, a person must be monitored long-term for increasing GH levels.

If surgery does not normalize hormone levels or a relapse occurs, a doctor will usually begin additional drug therapy. The current first choice is generally octreotide or lanreotide; however, bromocriptine and cabergoline are both cheaper and easier to administer. With all of these medications, long-term therapy is necessary, because their withdrawal can lead to rising GH levels and tumor re-expansion.

Radiation therapy is generally used for people whose tumors are not completely removed by surgery, for people who are not good candidates for surgery because of other health problems, and for people who do not respond adequately to surgery and medication.

Prognosis

Life expectancy of people with acromegaly is dependent on how early the disease is detected. Life expectancy after the successful treatment of early disease is equal to that of the general population. Acromegaly can often go on for years before diagnosis, resulting in poorer outcome, and it is suggested that the better the growth hormone is controlled, the better the outcome. Upon successful surgical treatment, headaches and visual symptoms tend to resolve. One exception is sleep apnea, which is present in around 70% of cases but does not tend to resolve with successful treatment of growth hormone level. While hypertension is a complication of 40% of cases, it typically responds well to regular regimens of blood pressure medication. Diabetes that occurs with acromegaly is treated with the typical medications, but successful lowering of growth hormone levels often alleviates symptoms of diabetes. Hypogonadism without gonad destruction is reversible with treatment. Acromegaly is associated with a slightly elevated risk of cancer.

Notable people

  • Andre "the Giant" Roussimoff (1946–1993), French professional wrestler and actor.
  • Mary Ann Bevan (1874–1933), an English woman, who after developing acromegaly, toured the sideshow circuit as "the ugliest woman in the world".
  • Salvatore Baccaro (1932–1984), Italian character actor. Active in B-movies, comedies, and horrors because of his peculiar features and spontaneous sympathy.
  • Paul Benedict (1938–2008), American actor. Best known for portraying Harry Bentley, The Jeffersons' English next door neighbour.
  • Eddie Carmel, born Oded Ha-Carmeili (1936–1972), Israeli-born entertainer with gigantism and acromegaly, popularly known as "The Jewish Giant".
  • Ted Cassidy (1932–1979), American actor. Best known for portraying Lurch in the TV sitcom The Addams Family
  • Rondo Hatton (1894–1946), American journalist and actor. A Hollywood favorite in B-movie horror films of the 1930s and 1940s. Hatton's disfigurement, due to acromegaly, developed over time, beginning during his service in World War I.
  • Sultan Kösen, the world's tallest man.
  • Maximinus Thrax, Roman emperor (c. 173, reigned 235–238). Descriptions, as well as depictions, indicate acromegaly, though remains of his body are yet to be found.
  • The Great Khali (born Dalip Singh Rana), Indian professional wrestler, is best known for his tenure with WWE. He had his pituitary tumor removed in 2012 at age 39.
  • Maurice Tillet (1903–1954), Russian-born French professional wrestler, is better known by his ring name, the French Angel.
  • Richard Kiel (1939–2014), actor, "Jaws" from two James Bond movies and Mr. Larson in Happy Gilmore
  • Pío Pico, the last Mexican Governor of California (1801–1894), manifested acromegaly without gigantism between at least 1847 and 1858. Some time after 1858, signs of the growth hormone-producing tumor disappeared along with all the secondary effects the tumor had caused in him. He looked normal in his 90s. His remarkable recovery is likely an example of spontaneous selective pituitary tumor apoplexy.
  • Tony Robbins, motivational speaker
  • Carel Struycken, Dutch actor, 2.13 m (7.0 ft), is best known for playing Lurch in The Addams Family film trilogy, The Giant in Twin Peaks, Lwaxana Troi's silent Servant Mr. Homn in Star Trek: The Next Generation, and The Moonlight Man in Gerald's Game, based on the Stephen King book.
  • Irwin Keyes, American actor. Best known for portraying Hugo Mojoloweski, George's occasional bodyguard on The Jeffersons
  • Neil McCarthy (1932–85), British actor. Known for roles in Zulu, Time Bandits, and many British television series
  • Nikolai Valuev, Russian politician and former professional boxer
  • Antônio "Bigfoot" Silva, Brazilian kickboxer and mixed martial artist.
  • (Leonel) Edmundo Rivero, Argentine tango singer, composer and impresario.
  • It has been argued that Lorenzo de' Medici (1449–92) may have had acromegaly. Historical documents and portraits, as well as a later analysis of his skeleton, support the speculation.
  • Pianist and composer Sergei Rachmaninoff, noted for his hands that could comfortably stretch a 13th on the piano, was never diagnosed with acromegaly in his lifetime, but a medical article from 2006 suggests that he might have had it.
  • Polyketide

    From Wikipedia, the free encyclopedia

    Polyketides are a class of natural products derived from a precursor molecule consisting of a chain of alternating ketone (or reduced forms of a ketone) and methylene groups: (-CO-CH2-). First studied in the early 20th century, discovery, biosynthesis, and application of polyketides has evolved. It is a large and diverse group of secondary metabolites caused by its complex biosynthesis which resembles that of fatty acid synthesis. Because of this diversity, polyketides can have various medicinal, agricultural, and industrial applications. Many polyketides are medicinal or exhibit acute toxicity. Biotechnology has enabled discovery of more naturally-occurring polyketides and evolution of new polyketides with novel or improved bioactivity.

    History

    Naturally produced polyketides by various plants and organisms have been used by humans since before studies on them began in the 19th and 20th century. In 1893, J. Norman Collie synthesized detectable amounts of orcinol by heating dehydracetic acid with barium hydroxide causing the pyrone ring to open into a triketide. Further studies in 1903 by Collie on the triketone polyketide intermediate noted the condensation occurring amongst compounds with multiple keten groups coining the term polyketides.

    Biosynthesis of orsellinic acid from polyketide intermediate.

    It wasn't until 1955 that the biosynthesis of polyketides were understood. Arthur Birch used radioisotope labeling of carbon in acetate to trace the biosynthesis of 2-hydroxy-6-methylbenzoic acid in Penicillium patulum and demonstrate the head-to-tail linkage of acetic acids to form the polyketide. In the 1980s and 1990s, advancements in genetics allowed for isolation of the genes associated to polyketides to understand the biosynthesis.

    Discovery

    Polyketides can be produced in bacteria, fungi, plants, and certain marine organisms. Earlier discovery of naturally occurring polyketides involved the isolation of the compounds being produced by the specific organism using organic chemistry purification methods based on bioactivity screens. Later technology allowed for the isolation of the genes and heterologous expression of the genes to understand the biosynthesis. In addition, further advancements in biotechnology have allowed for the use of metagenomics and genome mining to find new polyketides using similar enzymes to known polyketides.

    Biosynthesis

    Polyketides are synthesized by multienzyme polypeptides that resemble eukaryotic fatty acid synthase but are often much larger. They include acyl-carrier domains plus an assortment of enzymatic units that can function in an iterative fashion, repeating the same elongation/modification steps (as in fatty acid synthesis), or in a sequential fashion so as to generate more heterogeneous types of polyketides.

    Biosynthesis of carminic acid

    Polyketide synthase

    Polyketides are produced by polyketide synthases (PKSs). The core biosynthesis involves stepwise condensation of a starter unit (typically acetyl-CoA or propionyl-CoA) with an extender unit (either malonyl-CoA or methylmalonyl-CoA). The condensation reaction is accompanied by the decarboxylation of the extender unit, yielding a beta-keto functional group and releasing a carbon dioxide. The first condensation yields an acetoacetyl group, a diketide. Subsequent condensations yield triketides, tetraketide, etc. Other starter units attached to a coezyme A include isobutyrate, cyclohexanecarboxylate, malonate, and benzoate.

    PKSs are multi-domain enzymes or enzyme complex consisting of various domains. The polyketide chains produced by a minimal polyketide synthase (consisting of a acyltransferase and ketosynthase for the stepwise condensation of the starter unit and extender units) are almost invariably modified. Each polyketide synthases is unique to each polyketide chain because they contain different combinations of domains that reduce the carbonyl group to a hydroxyl (via a ketoreductase), an olefin (via a dehydratase), or a methylene (via an enoylreductase).

    Termination of the polyketide scaffold biosynthesis can also vary. It is sometimes accompanied by a thioesterase that releases the polyketide via hydrating the thioester linkage (as in fatty acid synthesis) creating a linear polyketide scaffold. However, if water is not able to reach the active site, the hydrating reaction will not occur and an intramolecular reaction is more probable creating a macrocyclic polyketide. Another possibility is spontaneous hydrolysis without the aid of a thioesterase.

    Post-tailoring enzymes

    Further possible modifications to the polyketide scaffolds can be made. This can include glycosylation via a glucosyltransferase or oxidation via a monooxygenase. Similarly, cyclization and aromatization can be introduced via a cyclase, sometimes proceeded by the enol tautomers of the polyketide. These enzymes are not part of the domains of the polyketide synthase. Instead, they are found in gene clusters in the genome close to the polyketide synthase genes.

    Classification

    Polyketides are a structurally diverse family. There are various subclasses of polyketides including: aromatics, macrolactones/macrolides, decalin ring containing, polyether, and polyenes.

    Polyketide synthases are also broadly divided into three classes: Type I PKSs (multimodular megasynthases that are non-iterative, often producing macrocodes, polyethers, and polyenes), Type II PKSs (dissociated enzymes with iterative action, often producing aromatics), and Type III PKSs (chalcone synthase-like, producing small aromatic molecules).

    In addition to these subclasses, there also exist polyketides that are hybridized with nonribosomal peptides (Hybrid NRP-PK and PK-NRP). Since nonribosomal peptide assembly lines use carrier proteins similar to those use in polyketide synthases, convergence of the two systems evolved to form hybrids, resulting in polypeptides with nitrogen in the skeletal structure and complex function groups similar to those found in amino acids.

    Applications

    Polyketide antibiotics, antifungals, cytostatics, anticholesteremic, antiparasitics, coccidiostats, animal growth promoters and natural insecticides are in commercial use.

    Medicinal

    There are more than 10,000 known polyketides, 1% of which are known to have potential for drug activity. Polyketides comprise 20% of the top-selling pharmaceuticals with combined worldwide revenues of over USD 18 billion per year.

    Polyketides
    Geldanamycin, an antibiotic. Doxycycline, an antibiotic. Erythromycin, an antibiotic. Aflatoxin B1 known carcinogenic compound.

    Examples

    Agricultural

    Polyketides can be used for crop protection as pesticides.

    Examples

    Industrial

    Polyketides can be used for industrial purposes, such as pigmentation and dietary flavonoids.

    Examples

    Biotechnology

    Protein engineering has opened avenues for creating polyketides not found in nature. For example, the modular nature of PKSs allows for domains to be replaced, added or deleted. Introducing diversity in assembly lines enables the discovery of new polyketides with increased bioactivity or new bioactivity.

    Furthermore, the use of genome mining allows for discovery of new natural polyketides and their assembly lines.

    Three-body problem

    From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Three-body_problem Approximate tra...