Psychology Basics: Development
To understand yourself you must first gain perspective on how you came to be where you are now. Looking back, it might seem as if there is some continuity between your first memory and what you experience today. But our memories change. They become distorted or imbued with different qualities after every new experience. The underlying reality is: your cells wither away and become replaced by new ones every seven years or so. The same is true for every carbon molecule in your body.
From the time we're conceived, we set out on a path of change, influenced by our environment, culture, biology and social interactions. Every moment that we've had to learn or adapt in the world is the moment we cease to be the person we were prior to.
"All the world's a stage, And all the men and women merely players; They have their exits and their entrances, And one man in his time plays many parts, His acts being seven ages. At first, the infant, Mewling and puking in the nurse's arms."
Many cultures around the world have unique stories and myths about how an individual transforms across time and what a society does to facilitate this transformation through various forms of rituals and rites of passage. In shamanic traditions, as young boys reach a certain age, the tribe collectively participates in a process of initiation that requires subjecting the boy to severely discomforting experiences. This is intended to dissolve the futile personality that characterizes boyhood to awaken a stronger, more capable man within. Why is this important? Contrary to the 3rd wave feminist narrative of the 21st century, men are conditionally valued based on what they can provide. This is universal among almost every culture in the world. It makes perfect sense to groom men to be more resilient and productive.
Some rites of passage observed among different tribes are tamer than others but the message remains the same: with any luck, as we pass through various challenges in life, we become more fit as a consequence. Concepts such as this are akin to stories of transformation all throughout history such as the resurrection of Christ or the iconic symbol of the Phoenix in Greek mythology who transcends the ashes and is reborn into something more robust.
Most modern societies today do not enforce rites of passage for children into adults with the exception of some religious groups. These traditions lose significance in a bustling population of millions in addition to living standards which constantly limit the exposure of hazards - perhaps even to the detriment of budding generations. Even so, the development of youth into adulthood occurs more or less naturally, remaining at the mercy of environment and social norms.
Gloves of Stinging Red Ants
Modern Methods of Examining Human Development
Over the last century, science has come up with special methods of researching age-related changes.
The first is what we call "longitudinal designs" whereby a single group of people is followed and assessed at different times as the group ages. Longitudinal studies have the advantage of examining age-related changes as they occur. The biggest drawback is the amount of time, money and resources made available to a single study. Participants also die, move away, or simply lose interest in divulging intimate details of their life.
Group 1 - 20-year-old subjects (1974)
Group 2 - Same subjects at 40 years old (1994)
Group 3 - Same subjects at 60 years old (2014)
A cross-sectional design evaluates age-related changes between participants in different age groups. Instead of following a single group of people from childhood to death, a cross-sectional study simply compares information gathered between existing age groups at the same time period.
Study 1 - 20-year-old subjects (2014)
Study 2 - 40-year-old subjects (2014)
Study 3 - 60-year-old subjects (2014)
Lastly, a cross-sequential design is essentially a combination of the former two methods. It compares subjects ranging in age at different points in time to determine age-related changes and age-related differences. What's more, this design helps us understand the difference between changes that occur from specific influences and changes that occur naturally as a person gets older.
- Group 1 - 20-year-old subjects (2014)
- Group 2 - 40-year-old subjects (2014)
- Group 1 - Subjects at 25 y/o (2019)
- Group 2 - Subjects at 45 y/o (2019)
Every generation has its own body of knowledge, cultural background and uniquely personal experience as history unfolds. A cohort effect is an impact on development that occurs as a consequence of a particular group people sharing a common time period.
Pros & Cons
Nature Versus Nurture
It's difficult to explain why certain behaviors and characteristics arise during one's development. Many branches of psychology try to explain them using their own language and often conflict with one another. The nature versus nurture debate remains at the forefront of developmental research.
Nature is the extent to which behavior and personality traits are influenced by genes, heredity, and physical growth. Nurture refers to everything outside the person, namely the environment and social structure.
Much has changed in our understanding of the human genome and the brain since the 1970's. The advancement of neuroimaging technology has given us a clearer view of how the brain works and how it maps onto what we understand about human behavior and mental processes. Genetic research has helped us identify strong biological contributors to disease and some behavioral characteristics. Even with these advantages, the underlying reality of development still remains somewhere between the realm of physical and environmental influences.
Let's say for a moment that you notice a small family whose members all share a similar set of mental or behavioral characteristics. You might even notice that these characteristics are more prevalent among those who are more closely related. The problem is: genes aren't the only thing that the family shares in common. They also share the same environment...
Over the last 50 years, over 14 million pairs of twins have been studied to determine exactly how much environment and genes impact traits. This is has inarguably been the meat and potatoes of research in developmental psychology.
To do this, two pairs of twins are examined for a study. A pair of dizygotic (fraternal) twins is selected, meaning that they developed from two separate eggs sharing only 50% of each other's genes. The second selected pair are monozygotic (identical) twins hatched from the same egg who share 100% of their genes.
If the fraternal twins share the same environment and the identical twins share the same environment, how do we explain behavioral differences if you notice a trait that is shared to a greater extent in a pair of identical twins? We might thus infer that since identical twins share twice as many genes in common than fraternal twins, there might a stronger genetic influence on traits.
The are two major flaws to this approach.
(A) there are more variations in traits among twins who differ in sex/gender
(B) there is more variation in the environment among fraternal twins than identical twins
At the end of the day, after the culmination of millions of studies like this, nature and nurture appear to play a 50/50 role in most cases. As discussed in an earlier article, there is a dynamic relationship between the activation of specific genes and influences from the environment responsible for those activations. For example, in the case of alcoholism in families, the natural genetic component is often dormant until a series of environmental influences trigger alcoholic behavior. i.e. trauma, abuse, poverty, social norms, etc.
Embryonic & Fetal Development
Here I will briefly cover embryonic and fetal development after conception. If you need a review of copulation and fertilization, click here...
After fertilization of a female egg, a zygote makes its exodus toward the uterus where it will be protected and nourished throughout the rest of its development. This is known as the germinal period which generally takes around 2 weeks for the mass of cells to successfully attach to the wall of the uterus and begin to grow. The placenta and umbilical cord also form during this period which provides nutrients to the zygote and filters out waste products. More importantly, during the germinal period, cells begin to take shape into distinct parts that will eventually become major organs such as the skin, heart, neural tube and so on.
From week 2 to week 8, the zygote transforms from a small mass of cells to a visible embryo marking the transition from the germinal to the embryonic period. During this period, cells continue to diversify and form the structures necessary for human function. By the end of the 8 weeks, the embryo is roughly 1 inch in length and has recognizable features that resemble eyes, nose, lips, teeth, arms, legs and a beating heart.
Critical Periods: The moment the embryo begins to receive nourishment from the mother, it becomes highly vulnerable to toxins and hazards such as drugs, alcohol, and viral infection. Exposure to hazards is likely to result in malformation of the embryonic structures - not least birth defects, mental retardation, and death. Specific structures are more vulnerable at different stages.
Limbs - 3-8 weeks
Heart - 2-6 weeks
Nervous System - 2-5 weeks
Teeth/Mouth - 7-12 weeks
The first 3 weeks of growth is the most likely for miscarriages and spontaneous abortions to occur. Sometimes these cases are idiopathic (no known cause) while others can be triggered by stress, trauma or toxicity. In the figure below is a list of harmful substances and pathogens to avoid during pregnancy.
From week 8 to birth (≈ 9 mos) is what's known as the fetal period wherein a tremendous level of growth occurs. The length of the fetus increases by roughly 20 times and its weight increases from approximately 1 ounce at 2 months to an average of 7 pounds at birth. The organs and limbs continue to develop while fat accumulates around the fetus until week 38. At week 38, the fetus is considered full term and most babies are born between 38 and 40 weeks. Stubborn babies sometimes require cesarian sections to remove and can be safer than traditional birthing.
Once an infant reaches 1 year of life, it has nearly tripled its birth weight and grown an extra foot in length. An infant brain triples in weight by age 2 which is roughly 3/4 of a fully mature adult brain. At 5 years, the brain is ninety percent complete. This type of rapid growth makes it possible for very complex thinking, problem-solving and memory to develop as children sprout up through life.
Jean Piaget is often remembered as the 20th century's most prominent child developmental psychologist but considered himself foremost a genetic (origins) epistemologist (the study of knowledge). As one of the earliest researchers of cognitive development, Piaget made direct and detailed observations of infants and children - three of which were his own. He would go on to make significant contributions in the understanding of how children constructed mental representations of the world by forming concepts and schemes (units of knowledge) in the face of new situations. For example, if a parent points to an image of a banana and says "that's a banana", the child will form a scheme around the basic features of a banana (assuming the image can hold the child's gaze for more than a moment).
This new scheme has a caveat: if the child sees an image of a lemon instead, they might say "banana" because both bananas and lemons are yellow. This is what Piaget referred to as assimilation whereby the child uses an existing scheme to deal with a new object or situation. The moment a child realizes that their existing schema does not work and needs to be modified is what he called accommodation. It is here that we can see how Piaget applies his observations to a more general theory of how humans acquire knowledge.
In the figure below, you'll notice Piaget's four distinct stages of cognitive development from infancy to adolescence.
Object Permanence: Knowing that an object still exists, even if it is hidden. The ability to form a mental representation of the object.
Egocentric: Inability to see the world from the perspective of another.
Conservation: The alteration of an objects' appearance does not change quantity or volume.
In summary, Piaget viewed children as active explorers of their environment, fully engaged in the discovery of new information. His ideas have been put into practice by allowing children to learn with hands-on experience, at their own pace and teaching them concepts appropriate to their cognitive capacity. Piaget also believed that games were the vehicle by which children learned how to socialize themselves, ultimately adding another dimension to their overall intelligence. If a child can learn to play well with others at an early age, they are more likely to do well across more sophisticated game-like systems as an adult.
Lev Vygotsky was another early pioneer in developmental psychology who made large strides in the Russian education system during the early 20th century. While Piaget seemed to place greater emphasis on interaction with objects, Vygotsky believed the role of others in child development was paramount.
Flash Case Study!
Vygotsky observed that children are able to grasp concepts much faster when someone else guides them by asking questions and providing examples. This is the process Vygotsky referred to as scaffolding - beginning with a stronger degree of intervention then slowly withdrawing as the learner improves.
Zone of Proximal Development
Vygotsky distilled this idea of cooperative learning and the degree to which a child is able to learn specific skills in what he called the "zone of proximal development"...
"...the distance between the actual developmental level as determined by independent problem solving and the level of potential development as determined through problem-solving under adult guidance, or in collaboration with more capable peers." (Vygotsky, 1978)
In layman's terms, it is the difference between what a child can do alone versus what a child can do with the help of another person. See figure below.
Depending on which expert you ask, the adolescent period ranges anywhere from 10-13 years old to 19-30 years old. In reality, this period cannot truly be defined by chronological age alone. Such ambivalence stems from a number of factors including sex/gender, brain development and independence from parents. The nature versus nurture conundrum strikes again. Does physical, mental and social development occur simultaneously? How do we define what it means for a child to "grow up"? Implicit in that metaphor is the idea that people grow physically whether they like it or not. Others might argue that a person has to demonstrate a certain level of wisdom or impulse control to be regarded as something other than a child.
In our first analysis, we'll begin by assuming that a child ceases to be a child when their body enters puberty. Physical changes occur in both primary sex characteristics (penis and uterus) and secondary characteristics (body hair and breasts). However, much more is happening behind the scenes. Deep within the young brain, the pituitary gland or "master gland" begins to signal a cascade of glandular activity and hormone secretion. These hormones influence a number of traits such as sexual drive, muscular growth, and emotions. On average, females experience the onset of puberty 2 years before males beginning around the age 10. The process of rapid growth as characterized by puberty takes roughly 4 years to complete, however, the brain continues to develop well into mid-adulthood. More specifically, the pre-frontal cortex of the brain responsible for impulse control, decision making, and abstract thinking does not fully stabilize until around the age of 25.
Cognitive development of adolescents is less clear than the visible aspects of physical development. Here we will examine the way in which adolescents think about themselves, their relationships and the world around them.
Watch the PBS Documentary Series "The Brain" With Your Amazon Prime Subscription
David Eagleman does an excellent job communicating the wonders of the brain to the general public. A must see!
Piaget's Formal Operations Revisited
Adolescents who are able to receive a formal education are more likely to move into Piaget's final stage of formal operations where more abstract thinking takes place. Teenagers can start pondering hypothetical situations in greater detail thereby envisioning what an "ideal" world might look like. However, they are not yet entirely unbridled from egocentric thought. Adolescents are often heavily preoccupied with their own thoughts and assume that their thoughts are as important to others are they are to themselves. This makes them susceptible to fallacies such as the "personal fable" and "imaginary audience".
Personal Fable - Convinced that their thoughts are unique. No one else has ever had thoughts like theirs. "You don't understand me", "I'm different from you". A false sense of invincibility that sometimes leads to unwanted pregnancies or vehicle accidents.
Imaginary Audience - Extreme self-consciousness. Believes that everyone is looking at them and are always at the center of attention.
Part of an adolescent's mental development is the basic understanding of "right" and "wrong". Many of our laws in the U.S. are designed around punishing criminal behavior based on an individual's degree of this understanding - hence the prohibition of the death penalty for criminals under the age of 18.
In the mid-1970's, a developmental psychologist from Harvard Lawrence Kohlberg outlined a theory of moral development among various age groups. See figure below.
Click image to enlarge
Kohlberg's Three Levels of Morality
One of the major criticisms of Kohlberg's research methods is that asking people what they "think" they would do in hypothetical situations is much different than what they would actually do. After all, morality is more about behavior than beliefs. Even so, Kohlberg's outline has since been refined and well accepted in the field of developmental psychology.
Piaget's Stages of Moral Development
Piaget believed that moral development began earlier in childhood when a child learns to properly act out the rules of games during play. Demonstrating a healthy ratio of cooperation illustrates the emergence of an implicit morality among groups. (This has also been observed in rats and primate subjects)
The most imminent problem faced by adolescent teens is identity versus role confusion. In this phase, a teen has to decide among a myriad of values and beliefs about political issues, career paths, and marriage. Out of these choices, a constant sense of self must be preserved. Who am I? Where do I belong? It is here an adolescent begins to feel the full weight of demand from their peers, parents, and the rest of society.
Teens who are able to overcome obstacles early on in life (see video below) are better prepared to resist peer pressure and unhealthy decisions moving forward. Those who are not properly socialized during their formative years enter adolescence with a lower self-esteem and general lack of trust for others.
Erickson's 8 Stages of Psychosocial Development
We once again return to the struggle for proper definitions. Adulthood is sometimes referred to as the period of life from age 20 to senior. In other cultures, adulthood is reached shortly after puberty as discussed in the beginning of the article.
For our purposes, we will examine some of the changes that occur between age 20-40 and 40-65. Remember that every individual has their own unique experiences, environment, culture, socioeconomic status, and genetic background. This segment is meant to highlight some of the biological imperatives associated with aging and common problems that people encounter during these spans of life.
Finish this sentence: "Adulthood is the..."
Early Adulthood (20-40)
By age 20, our physical maturation is complete. Neither men nor women will continue to grow any taller although some might gain more weight. The first 10 -15 years of early adulthood is undoubtedly the period in which people are at their highest physical peak such as superior muscle strength (heart), sensory and reflexive abilities. The majority of successful world-class athletes generally fall within this age bracket.
Around the age of 30, people start to notice small effects of aging including visual degradation, thinning or graying of hair, dryer skin and decreased immune function.
Between age 20 and 40, intellectual ability doesn't change much overall. It is generally accepted that fluid IQ (ability to solve new problems) begins to slowly decline sometime in the mid 20's while crystallized IQ (acquired knowledge and experience) increases. But newer study findings from MIT suggest that different aspects of intelligence peak at different stages - some as late as age 40. In summary, as we age, we get better at some things and worse at others, as has been fairly self-evident since birth.
During this period, physical changes related aging become much more apparent. Women in their 40's will experience a decline in estrogen as their body's reproductive system begins to shut down; otherwise known as menopause. Symptoms include hot flashes, mood swings, or sudden weight gain.
Men experience something similar to menopause called "andropause" as testosterone and other hormones begin to fade. Symptoms include fatigue, irritability, and sexual dysfunction.
During the latter portion of adulthood is also where we begin to see more instances of health problems in both men and women - most often as a consequence of poor choices early on such as smoking, excessive alcohol consumption, overeating, and stress. Statistically, the most frequent causes of death during middle age are heart disease, cancer, and stroke - in that order.
Changes in memory are the most notable in middle-aged cognition. People will begin to struggle more with recalling words and details about particular past events. The difficulty of memory retrieval actually has less to do with physical aging and more to do with stress and the sheer amount of information someone at this age has had to keep track of. A study from 2012 posits that the more one thinks of positive experiences from the past, the more one can form new memories moving into the future. This suggests that the areas of the brain responsible for processing emotional content appear to have a strong connection with areas of the brain involved in memory storage.
I feel compelled to share a quote by author Maria Popova that appeared serendipitously to me the day of my writing this particular segment.
"In my own experience, the most withering aspect of depression is the way it erases, like physical illness does, the memory of wellness. The totality of the erasure sweeps away the elemental belief that another state of being is at all possible — the sensorial memory of what it was like to feel any other way vanishes, until your entire being contracts into the state of what is, unfathoming of what has been, can be, and will be."
The National Institute of Mental Health estimates that 16 million people in the U.S. currently suffer from some form of depression with roughly 8% of them between the ages of 18 and 22. Over prolonged periods of time, this can pose serious risks to overall health - not least memory loss.
At the end of the day, the most effective way to preserve the brain and prevent early onset of neurodegenerative diseases like Alzheimer's is regular physical exercise. It's an indisputable fact at this juncture. Get out there and move your body. Your body is your brain!
Beyond Piaget - Postformal Operational Thinking
If we look back at Piaget's 4th and "final" stage of operational thinking, we notice a general ability to think abstractly and engage in deductive reasoning beginning somewhere in adolescence. Other developmental psychologists have since identified a 5th stage called postformal thinking which is characterized by decisions that are made based on dialectics and the ability to handle emotionally charged situations. This level of cognition is most recognizable in those over the age of 35 and it is here we begin to see more concrete notions of moral virtue and principles.
As a society, we tend to have certain expectations of what people should achieve at different stages in life; but the landscape is changing rapidly. People are living longer, average IQ is increasing, overall wealth is growing, and technology is helping people become more educated and self-sufficient. To avoid over-generalization, I'll end this segment by acknowledging that anywhere along this age spectrum people make impactful decisions at different times such as earning a higher education, getting married, and advancing their careers. Unfortunately, having children is limited to women pre-menopause but men can have leave offspring at pretty much any point before death. In the next segment, we'll cover common styles of parenting.
Almost everyone would agree that rearing children is one of the most important responsibilities in the world. How our children are shaped during their early years is critical to who they will become as adults. You might be familiar with the modern sarcastic trope "some people's kids". While this is tongue-in-cheek in most cases, people are also trying to communicate that the existence of a difficult or awkward person in the world is a failure on part of parents thus begging the question: is there a right or wrong way to raise kids? In the late 1960's, a developmental psychologist by the name of Diana Baumrind outlined the 3 most basic styles of parenting.
This style is highly concerned with rules. It is generally characterized as rigid, controlling, and uncompromising. Failure to meet standards usually results in physical punishment. Children raised this way tend to become resentful and withdrawn. It would be fair to make a distinction between battering parents and those who simply resort to physical discipline as rules are broken. Examples of this can be seen in military households where children are held to the same standard as enlisted soldiers. However, if the physical disciplinary action carries on too often and unchecked then it will undoubtedly result in some form of trauma or behavioral disorder.
The permissive approach places very few demands on children. It can be further divided into two types of permissive parenting:
- Permissive Neglectful - Parents are not actively engaged with children at any point unless the children's behavior somehow interferes with what the parent(s) are doing.
- Permissive Indulgent - Parents are highly involved with the children with an even greater emphasis on meeting the children's demands.
Permissive parents generally refuse to set any boundaries and allow them to act out in any manner without consequences. Children under this type of guidance are overly dependent, immature, and lack the necessary skills that would otherwise enable them to deal with social adversity.
The final approach combines some of the beneficial aspects of the former two. It places limits on behavior and establishes rules while maintaining love, affection, and respect. Authoritative parents are generally more thoughtful in dialogue with their children. They may also establish a democratic style, allowing the child to have some input on the formation rules but also maintaining the role as the decision maker(s). Punishment is doled out in the form of restricting priveledges but can escalate or de-escalate depending on the child's level of cooperation and understanding of the rules. Children raised this way tend to be self-reliant and more confident in social settings.
As parents, we try to do our best and do what we feel is right. Sometimes the world changes faster than we can aptly prepare our children for. Some of us have an intuition that guides our parenting methods depending on the needs of the child. Like anything else in this world, too much of anything is never a good thing. Finding a healthy balance and a willingness to learn with your child is likely the safest bet. The most important thing is to enjoy being around them. Don't let your relationship with them become something that you'll look back on later with regret.
Poll for Parents
Which style of parenting do you identify with?
End of Life
Beyond the age of 65, the body begins to break down becoming less agile, energetic and focused. Hopefully, by this time, seniors retire and devote most of their time to convalescence and enjoying their family. They bring to bear a breadth of wisdom from a long life lived and share their experiences, failures, and triumphs with others. With any luck, others may learn from them rather than condemn them as mere avatars of the status quo.
Unfortunately, seniors eventually reach a timely or untimely fate. The average life expectancy for both men and women currently in the U.S. is between 78 and 81 years.
Dying and losing loved ones is undeniably one of the most difficult imperatives we face in this life. For some, a loss is a crippling experience that can last a lifetime but for others, it remains in perspective and can be viewed as a beautiful demonstration of natures' checks and balances.
Before I end this article, I would be remiss if I didn't review the classic emotional stages of grief that we experience after losing loved ones. Note that these are not to be expected in any particular order*
- Denial - A natural defense mechanism. The mind blots out the glaring reality of the situation by convincing oneself that it's business as usual.
- Anger - As people attempt to remind us of such a reality, we become frustrated. Even if we manage to move out of denial, we might become upset with the person or object of our loss. It's also helpful to think about anger as the volatile chemical reaction to a deeply compartmentalized powder keg of sadness.
- Bargaining - As we begin the process of acceptance, we try to negotiate with our pain - inevitably getting caught up in "what if" statements to ourselves and others. Sometimes we try to strike a deal with God or convince ourselves that we might still possess some control over the situation or make lofty resolutions to turn a new leaf in life. This stage is the dawning of a realization that we could do better to make future losses justified by acting different and improving our relationships.
- Depression - As we finally realize that we are not in control of the situation or the feelings that arise as a consequence, we become powerless. This is often accompanied by long periods of negative thought patterns, loss of motivation, loss of appetite, and fatigue. Sometimes these periods are temporary while others last for years to come.
- Acceptance - Not to be confused with being "happy" or "okay" with a loss. Acceptance is a shift in attitude about the reality of our powerlessness and the natural cycle of life. In this phase, we come to understand that we do, in fact, have some control over the ultimate reality of our own lives and would be better if we continued to care for ourselves and others so that the process of adjustment isn't nearly as torturous.
I believe it's important to understand the phasic process of these universal experiences because to move from one to the other is to move one step closer to finding peace and acceptance. The more we become familiar with this process, the more we see how it can apply to any inevitable form of loss in life.
Often feelings of sadness, guilt, and depression are natural and appropriate responses to tragedy. It would be unusual NOT to feel this way. So, before you resort to self-medicating with drugs or alcohol or perhaps even pharmaceutical products, remember that the only path to finding your way out of these experiences is to move through them. By simply masking the experience day after day is to remain trapped in the moment of loss forever.
Ciccarelli, S. & White, N. (2009) Psychology. Fourth Edition. Pearson Education. Upper Saddle River, NJ.
Piaget, J. (1957). Construction of reality in the child. London: Routledge & Kegan Paul.
Piaget, J. (1932). The moral judgment of the child. London: Routledge & Kegan Paul.
Vygotsky, L. S. (1978). Mind in society: The development of higher psychological processes. Cambridge, MA: Harvard University Press.