Module 4
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Module 4: The Level of Intimate Social Interactions: Development
Monday, June 3 – Sunday, June 9

Required Reading/Viewing:

Principles of Psychology, Chapters 8–9
(Pages 322–361; 364–372; 386-397)

Module 4 online content

View this video:

Social Media Dangers Documentary — Childhood 2.0 [Video]. Youtube.
Note: There some difficult topics here – child abuse, suicide, etc.
Discussions:	
Module 4 Discussion

Initial responses due Thursday, June 6, 9:00 AM ET
Two peer response due Sunday, June 9, 9:00 AM ET
Leader response due Tuesday, June 11, 9:00 AM ET
Assignments:	Film Response worksheet 3 due Sunday, June 9, 5:00 PM ET
Live Classrooms:	
Monday, June 3, 7:30–9:00 PM ET

Activity:	Complete Module 4 Review and Reflect, due Monday, June 10, 11:59 PM ET
Welcome to Module 4

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Learning Objectives

List two major themes/debates in developmental psychology and give an example of each.
Describe stages in prenatal development.
Describe Piaget’s theory of cognitive development.
Describe and give examples of Kohlberg’s Theory of moral development.
Describe how “attachment” between infants and caregivers is measured and why it is important.
List milestones in language development and how the environment supports language development.
Compare cross-sectional and longitudinal research designs and give examples.
Developmental Psychology

This branch of psychology is focued on how people change physically, mentally, and socially over the course of their life span. At each period of the lifespan, developmental psychologists study numerous factors at all of the levels that I introduced the first day of class, including biological, psychological, small intimate interactions, the larger social context, and culture.

major themes of developmental psychology
Major Themes in Developmental Psychology

A number of major themes recur in the study of developmental psychology, and I outline these below.

Basic Developmental Stages

The first important theme is the idea that individuals go through basic developmental stages. I’m going to introduce several stage theories. According to stage theories, individuals go through various periods of development referred to as stages. At each stage, development is not only quantitatively different (that is to say, there is more of something, like vocabulary increases in language development) but also qualitatively different (that is to say, one goes about things in a completely different way—not just “more” but also “different”). At each stage, the individual is very different in kind. The idea of stages has a number of implications:

Implications of Stages

Stages are roughly defined by age, although a certain amount of variability exists between individuals. There are also sudden stage-related changes. We will talk about this when we talk about cognitive development and language development. Although there is definitely evidence for stages of development, much of our physical, mental, and social development occurs gradually, unfolding over time.

There also may be critical periods in development. Critical periods are times in which a certain developmental event or task must take place. If it doesn’t happen at that critical period, it will never happen normally. There are also sensitive periods where it is best to accomplish this developmental task, but it is still possible at other times. A good example of this is with second language learning. A second language is most easily learned during childhood, although, with a lot of work, it can be learned later. Childhood is a sensitive period for the learning of a new language.

Nature versus Nurture

The second important theme is nature versus nurture. This is an old debate about how much of a person’s personality, capabilities, and other characteristics are determined by nature (genetics, what we bring into the world when we are born) and nurture (the way in which the environment supports or doesn’t support our development). Now the truth is, both are obviously very important. What we are most often interested in understanding is the interaction between nature and nurture.

So let’s begin looking at development from the time of conception, through the prenatal period and into infancy. How does the young child become who he or she is?

Genetic Contributions

In recent years our understanding of genetic contributions to all sorts of behavioral characteristics has exploded. Research has examined genetic contributions to intelligence, emotional stability, mental health disorders, personality, etc.  Behavioral genetics, combines genetics and psychology and helps us to understand the kinds of behavioral characteristics that are transmitted genetically from parent to child.

So let’s go through some of the basics. Many of you, probably most of you, have taken biology.

chromosome, dna, and the cell itself
You know that our chromosomes are long threadlike structures that look a bit like a twisting ladder and are composed of deoxyribonucleic acid or DNA. DNA is the chemical basis of heredity and carries genetic instructions in the cells of our body.
The gene is a basic unit of heredity, and genes direct the development of particular kinds of characteristics, including some behavioral characteristics. Now I’m not going to cover the entire biology of genetics here, but I do want to think about how it applies to behavioral characteristics.
As you are aware, at conception your biological mother contributes 23 chromosomes, and your biological father contributes 23 chromosomes; this new combination makes the unique you. Your new chromosomes contain approximately 24,000 genes. Although some genes have direct effects, and I’ll talk about some examples of that in a minute, most traits are “polygenetic” or influenced by more than one gene (e.g., our height is influenced by at least four genes). Some simple traits, such as eye color (light or dark), are determined by a single gene.
I like to define a couple of additional terms.

First, your genotype describes your underlying genetic makeup and it may include genetic instructions for traits that are never actually displayed (the gene is turned off).
Second, your phenotype refers to the observable traits or characteristics, and it is determined by the interaction between genes and the environment. Let me give you an example. Do you have freckles? Well freckles are caused by a gene, but this gene will only display itself under certain circumstances. If you have the freckles gene and you are exposed to sunlight, you will develop freckles. But think about rich white women on plantations in the South during the Antebellum era. These women really had no jobs at all (after all, they were completely taken care of by slaves), and having extremely white creamy skin was considered the height of beauty. These women would carry parasols or wear hats and long sleeves—all to avoid too much contact with the sun. Did some of them have the freckles gene? Who knows! On the other hand, if you have the freckles gene today you are more likely to display it, as most of us are going around in short sleeves during the summer and warming ourselves in the sun (ah!). There has to be an interaction between genetics (the freckles gene on the genome) and the environment (the sunlight) for that trait to be displayed in the phenotype.
Third is the idea of a dominant gene. You get one gene (called an allele) from your biological mother and one from your biological father. Dominant genes are those that will display themselves if even one allele is present. You only have to have one dominant gene in order for the trait to be evident. For example, curly hair is a dominant trait. If you got the straight hair gene from your biological mother and the curly hair gene from your biological father, you’re likely to have curly hair.
Fourth is the recessive gene. A recessive gene contains genetic instructions that will only be expressed if the individual has TWO recessive alleles (one from each biological parent). On the next set of slides, I give you the example of tongue rolling, so let’s go through these…
person rolling her tongue
Odokuma, E.I., Eghworo, O., Avwioro, G.O., & Agbedia, U. (2008). Tongue Rolling and Tongue Folding Traits in an African Population Rasgos de Lengua Enrollada y Lengua Doblada en una Población Africana.
Do you see the image on this slide? This is tongue rolling. Some of you can do it and some of you can’t. I really don’t think it’s a great virtue, so if you can’t do it don’t feel bad! Apparently, the ability to roll one’s tongue is determined by one dominant gene. Can you believe that? If you look at the table below, you can see how it works.

Along the top row is the genotype. We refer to a genotype as “homozygous” when both biological parents contribute the same type of gene/allele (dominant or recessive). We refer to a genotype as “heterozygous” when each biological parent contributes a different type of gene (one dominant, one recessive).

Genotype	Homozygous	Heterozygous	Heterozygous	Homozygous
Parental Alleles	Mother: Tongue rolling	Father: Tongue rolling	Mother: Tongue rolling	
Father: Non-Tongue rolling

Mother: Non-Tongue rolling	
Father: Tongue rolling

Mother: Non-Tongue rolling	
Father: Non-Tongue rolling

Phenotype	Tongue rolling	Tongue rolling	Tongue rolling	Non-tongue rolling
So let’s go through it; remember you only have to have one dominant gene for the trait to be expressed in your phenotype. So, in the first case you are homozygous for the dominant tongue-rolling gene as both your parents gave you a dominant gene for this trait. So your phenotype is positive for tongue rolling. (Isn’t this exciting?) In the next case, your mother had the dominant tongue-rolling gene, but your father gave you a recessive “non-tongue-rolling” gene. You are still a tongue roller, but your genotype is heterozygous! In the next case your mother had the recessive non-tongue-rolling gene, but your father gave you a dominant tongue-rolling gene. So, again, you are heterozygous, but you are a tongue roller (you have one dominant gene). In the last case, both of your parents gave you the recessive non-tongue-rolling gene. You are homozygous for the tongue-rolling gene and you cannot do tongue rolling. But wait! It turns out that tongue rolling is not entirely genetic! You can still learn the skill. But, why bother?

Other Examples of Recessive Traits

Susceptibility to poison ivy (oh I hope you aren’t homozygous for that one; I unfortunately am!), straight hair, and some diseases (examples include sickle cell disease and phenylketonuria or PKU) are examples of recessive traits.

Now, your sex chromosomes are the 23rd pair of chromosomes in humans. They determine your biological sex (gender is a separate issue, as it speaks to one’s identity and not to a biological characteristic). Instructions on these genes direct the development of your gonads in utero (among other things). This gets us to the topic of sex-linked recessive characteristics. Females have two large X chromosomes for the 23rd pair—one from their biological mother and one from their biological father. Males have one large X chromosome for the 23rd pair (from their biological mother) and one smaller Y chromosome (from their biological father). There are more genes on the X chromosome than on the Y chromosome. If you think about it, the Y chromosome, shaped like a Y, is missing a whole leg of potential genes. So any genes for recessive traits on that leg of the X chromosome 23 will be displayed (there is no other gene to contradict them). This is why men are more likely to have these sex-linked characteristics, as they are caused by recessive genes on chromosome 23. Examples of sex-linked traits include colorblindness, hemophilia, and male pattern baldness. For a woman to have any of these characteristics she would have to have genes from both biological parents that were recessive for these traits (not common).

Autosomes and the sex chromosomes
Source: National Human Genome Research Institute
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The human genome project identified all estimated genes on our human chromosomes. Although we know where they are, we don’t know what they all do. But let me point out a few that are particularly interesting.

Alzheimer’s disease. There are some forms of Alzheimer’s disease, particularly those with very early onset, that are genetically determined. You can actually take a genetic test to see if you will have this early onset form of Alzheimer’s disease (although it is usually only recommended if it runs in your family). There are other forms of Alzheimer’s disease that may be partially genetically determined (risk genes).
Amyotrophic lateral sclerosis or ALS results in progressive degeneration of motor neurons in the spinal cord, leading to paralysis. Some forms of ALS (maybe 5 to 10%) are caused by familial transmitted genetic mutations.
Huntington’s disease is a particularly interesting example of a genetically transmitted disease. The Huntington’s gene is a dominant one and if you have the gene you will develop the disease. The disease usually begins to show symptoms during a person’s 40s, although it can onset earlier in some people. The story of how the Huntington’s gene was discovered is a fascinating one and I encourage you to read more about it. But we will move along to a few other topics.
Source: National Human Genome Research Institute
Another example of a genetically determined medical condition is Down’s syndrome. In this syndrome individuals typically have mild intellectual disabilities, short stature, and a distinctive appearance. Down’s syndrome is not “inherited” but rather a defect that occurs during meiosis when egg and sperm come together to form a new genetic being. In the case of Down’s syndrome, the process results in what is called a trisomy on the 21st chromosome. Instead of two chromosomes there are three (thus a trisomy).
As we learn more about the human genome and its potential impact on behavioral health, risk of disease, and other outcomes, families face many difficult decisions. If you could get a genetic test that would tell you 100% that you would get a terrible disease in your 40s and there was no treatment, would you want to take the test? What happens if your health insurer or employer finds out? Lots of difficult questions!!

Ok, so having reviewed some basic information on genetics, let’s talk about how the baby develops physically before and after birth.

Physical Development

From the time the egg and the sperm get together and continuing throughout childhood, we see huge changes in physical development in a short period of time.

Prenatal

Let’s focus first on the prenatal stage, that is the stage of development before the baby is born. The prenatal stage is divided into three periods.

The first period of prenatal development is known as the germinal period, and it lasts for approximately two weeks. We refer to the developing organism as a germ or zygote. Two major developments occur during this time. First, the cells of the zygote rapidly divide, expanding in size. Second, the zygote implants in the lining of the uterus, where it will grow and develop for the next nine months.

Germinal Period

Source: Human Development
The second period of prenatal development is known as the embryonic period, and it lasts from approximately week 3 through week 8. A number of important events begin to unfold during this period. First, cell growth accelerates and cells begin to differentiate, with those that will become heart cells becoming different from those that will become skin cells or bone cells, etc. The organs and major systems of the body form, and genes on our sex chromosomes (chromosome 23) trigger the initial development of the sexual organs. Second, the amniotic sac where the baby will float for the next nine months develops, as does the umbilical cord that will transmit vital nutrients to the baby and will carry away waste. Third, the baby becomes increasingly vulnerable to the impact of teratogens, which are harmful substances that can cause defects in the developing embryo (and later the fetus).


Source: Carnegire Collection of Embryos
Here are some examples of teratogens:

Radiation. For the women in the class, you’ve probably been asked before you’ve had your dental X-rays whether or not you were pregnant. This is because radiation is a teratogen. If you are pregnant and need to get X-rays, you probably should wait until after the baby is delivered.
Toxic industrial chemicals. Let’s face it, mercury, PCBs, and other toxic industrial chemicals probably aren’t good for any of us, but they are particularly bad for the developing baby. It’s important to avoid exposure to these during pregnancy.
Certain diseases. Rubella, syphilis, AIDS, and many others can have a very negative impact on the development of the baby. This is one of the reasons that it is particularly important for pregnant women to take good care of their health, get prenatal care, and avoid exposure to diseases. We will get into other examples of this later in the semester when we talk about mental illness. The impact of any particular teratogen will depend on many factors, including timing (when during pregnancy the exposure occurs), maternal health, maternal age, and nutrition. I want you to look at the next slide, but don’t panic! There’s a lot of information here, but I only need for you to take away two important points.
fetal development
Source: Researchgate
The first point is that different organ systems develop at different times and therefore may be most vulnerable at different times during prenatal development. For example, the heart is developing during approximately weeks 7 to 8, and it is during this period that it is most vulnerable to the impact of teratogens that affect cardiac development. The second point to notice is that the development of the central nervous system occurs over a long period of time, making it vulnerable to the impact of teratogens throughout much of gestation.

Drugs. It is very important for a pregnant woman to talk to her doctor before taking drugs, either illicit drugs, over-the-counter drugs, or prescription drugs. Interestingly one of the drugs that has a particularly negative impact on the developing baby is alcohol. Many people would speculate that heroin or cocaine would be far worse (after all, they are illegal!), but alcohol is very bad. Numerous studies suggest that alcohol exposure is one of the main causes of birth defects in children. Nowadays pregnant women are cautioned against using any alcohol (having any alcoholic beverages at all) during pregnancy. As a person who very much enjoys wine, I would still suggest that any woman put that bottle away in a safe place and enjoy it after the baby is born. Additionally, if a woman is breast-feeding, it’s best to avoid alcohol (and other drugs) for that time as well, as those substances can enter breast milk and impact the infant.
The third period of prenatal development is known as the fetal period. At this point we refer to the developing child as a fetus. The fetal period extends from week 8 until the baby is born at approximately 40 weeks. The fetus is rapidly developing and gaining in size and ability. By the end of the 3rd month, the fetus can move its arms, legs, mouth, and head. It’s interesting to me that when my mother was pregnant (in the 1960s), doctors, pregnant women, and their partners had little idea about what the baby might be like until he or she arrived. Now, using sonograms, you can get a very good picture of how the baby is developing. It’s fascinating to look at a sonogram and realize that the baby is actually sucking her thumb in utero! During the 4th month, mothers began to experience what is known as quickening, that is, the movements of the baby. At first the mother may begin to think that she is having a bad tummy episode (maybe thinking that she had a dinner that was a bit too spicy), but it’s that baby moving! By the end of the 5th month, most of the brain cells are already in place, although they will continue to develop until birth and certainly thereafter. By the end of the 6th month, the baby’s brain activity is similar to that of a newborn baby. During the final few months of development in utero the baby is putting on weight and the lungs are continuing to develop, as the baby is preparing to live outside the uterus.

Newborn

Now that we’ve talked about prenatal development, let’s talk about what happens when the baby arrives.

The new baby comes into the world well-prepared. Now, many people when they see a newborn may think that baby is a fairly incompetent individual, but I’m telling you that that is not the case! I would argue that that baby is ready to do what is needed to thrive. This newborn is competent! So what does the newborn need to do to survive? Two main things: gain weight and connect with the supportive social world around her. The newborn comes into the world with the skills that allow her to do this. What are these skills?

Reflexes. The baby has a number of reflexes that contribute to her survival. First, they have the rooting reflex. If you brush a baby’s cheek with your finger, the baby will turn their head toward your hand and open their mouth. That newborn is ready to feed. Think of this: the mother’s breast brushes across the infant’s cheek, and the infant turns their head and is ready to breastfeed. This rooting reflex is there. Second, they have the sucking reflex. If you put your finger on the baby’s lips, they will begin to suck. Again, ready to be fed. So that baby is ready to gain weight. Third, and interestingly, the newborn has the grasping reflex. An infant can hold her weight with her grasp. That’s pretty amazing. This grasping reflex may be evolutionarily quite old. Think of other primates. When the chimpanzee baby is born, it needs to hold on to its mother as she swings from tree to tree. That grasping reflex is essential to his survival, so perhaps the grasping reflex is an old one from an evolutionary standpoint, one that we had when the baby still needed to really hold on. Of course now we have car seats, and baby carriers, and strollers, so perhaps the grasping reflex doesn’t have quite the same value as it once might have had.

Social attunement. Interestingly, the newborn is able to differentiate between their mother and other human beings by both voice tone and scent. The baby is prepared to make that crucial social connection. Although vision is the least developed sense at birth (indeed, the newborn is legally blind), the baby is able to see well from about 6 to 12 inches. This is the perfect distance for the baby to make eye contact while breastfeeding or taking a bottle! And so the relationship begins. Finally, babies are drawn to human voices; they are capable again of making those human connections that are so important to their survival.

Infancy

The first two years of life are called infancy. During this time, there are rapid and dramatic changes on many fronts.

Physical Development in Infancy

So what’s happening early on to that newborn baby? Well, at birth the newborn’s brain is approximately 25% of its adult weight. In contrast, the baby’s total weight is about 5% of its adult weight. The baby has a very heavy head! The baby’s brain has almost all of the neurons it will ever have. However, the connectivity of the human brain increases radically in the first two years of life, particularly, as the number of dendrites increases and the axons of many of the neurons acquire myelin.

Major Milestones in Motor Development

Motor Milestone	Mean Age (when 50% of infants have achived milestone)
Lifts head 90 degrees while on stomach	2.2 months
Rolls over	2.8 months
Sits with support	2.9 months
Sits without support	5.5 months
Stands with support	5.8 months
Crawls with support	7.0 months
Walks with support/cruises	9.2months
Stands independently	11.5 months
Walks independently	12.1 months
Walks up steps	17.0 months
Kicks ball forward	20.80months
Monk, Catherine & Hane, Amie. (2014). Fetal and Infant Brain–Behavior Development: Milestones & Environmental Influences. 10.1093/oxfordhb/9780199778072.013.20.
What are some of the major milestones of physical development? First, the baby can lift his or her head at about 2 months of age. Second, the baby can begin to roll over at about two and a half months of age. Be careful not to leave that baby alone on a bed! By about 3 months the baby can sit up if propped up by pillows. By about 6 months of age the baby can sit on his or her own. You can tell how long the baby has been sitting by how adept they are at sitting. A very new sitter will look unstable and will fall over easily if he or she reaches for something. The experienced sitter can turn and reach and do all sorts of activities while sitting.

By about six and a half months the child can stand holding on. Interestingly, as a child is developing these skills, he may become distracted from other developmental tasks. For example, the child who was sleeping through the night may stop doing so when he begins to walk or engage in other physical activities. He may not eat as readily. It’s hard to do all those other things when your focus is on walking! I remember when my son was first able to pull up and stand in his crib. He would spend so much time standing up, but then would start to cry because he couldn’t get down! We would then go in and help him down, and he would of course pull himself back up—he was so proud of himself. By about nine months, the child can begin to walk holding on, or what we call cruising. It’s amazing how far a child can get by holding onto a table while walking then moving gently to a nearby chair and then to a sofa. By about one year, children are often taking their first steps and walking. They then learn to walk backward, to walk upstairs, to kick a ball, and to do all sorts of other physical feats. It’s amazing to think that in those first two years they go from being unable to hold up their own heads to being able to run through the house.

One thing I want to note is that there is variability in when children achieve these developmental accomplishments. Some children are early walkers and some are late walkers. When a child begins to walk tells you very little about their athletic skill or anything else. It’s just a developmental difference and probably not very important. Now you may have noticed one milestone that I never mentioned. Can you think of what it might be? Well, it’s crawling. Now the reason I didn’t mention it is because it’s not really a milestone. It’s not necessary. Some babies crawl and some don’t. Sometimes the ones who are very good at crawling may begin to walk a little bit later; after all, if you are getting around just fine by crawling, what’s the point of trying to walk? It’s funny to watch infants crawling—some creep along on all fours, some do a crabwalk on one side—they all are different. I remember my own son the first time he tried to crawl toward an object that he really wanted—he ended up going backward! Boy was that frustrating.

Finally, I’d like you to remember two TRENDS in development. First there’s the cephalocaudal trend. Cephalo means head; caudal means tail. So the cephalocaudal trend is from head to tail. Physical development in utero proceeds this way, as does physical skill in infancy. In utero the head develops and then development continues downward toward the feet; in physical skill the child first learns to lift her head, then control her trunk (rolling over and sitting up), then walk. In each case it goes from head to “tail.” Second, there’s the proximodistal trend. Proximo means close; distal means far. In utero, the trunk and limbs develop first then the fingers and toes; in physical skill, the child begins to gain control over the trunk, then arms and legs, then hands and fingers—gross motor control (proximo) and is followed by fine motor control (distal).

Social and Personality Development

As noted earlier, forming social relationships and emotional bonds with caregivers is crucial to infants’ development, and this process starts on day one. Let’s talk about what infants bring into the world with them when they arrive and how those relationships with caregivers develop.

Temperament

Babies have inborn characteristics or predispositions to behave and react in certain ways, and we call these characteristics and predispositions their temperament. Temperament includes the intensity and quality of emotional reactions, activity level, attention, and self-regulation. In the 1950s two researchers, Chess and Thomas, were studying infants and began to rate them on a variety of characteristics. Based on these observations, they placed children into one of four categories. First, some of the babies were categorized as “easy.” These babies adapted easily to new situations, had generally cheerful moods, and had regular sleeping and eating patterns. I hope, if and when you have a baby, you have an easy baby, as this just makes your life, well, easier.

Second, some of the babies were categorized as “difficult.” These babies were intensely emotional, cried a lot, and had irregular sleeping and eating patterns. You will love your baby regardless, but these difficult babies can be, well, difficult. Third, some of the babies were categorized as “slow to warm up.” These babies had a low activity level, would withdraw from new stimuli, and adapted slowly to new situations. I guess you could say these babies were a little bit anxious. Fourth, and finally, the other babies were categorized as average, mostly because they didn’t really fit into any of the other categories neatly. These differences in temperament are probably biologically-based—due to physiological differences in heart rate, brain waves, hormone levels, and many other characteristics. Many of these differences are likely due to genetic factors.

Although Chess and Thomas put the babies into categories, more recently researchers have focused on dimensions of temperament. A dimension means that the temperamental characteristic ranges from low levels to high levels rather than being a category. Mary Rothbart studied infant temperament and described a number of dimensions, as you can see below.

The first is activity level. Some babies are highly active, some moderately so, and some have low activity levels. Dr. Kimberly Saudino in the Department of Psychological and Brain Sciences at Boston University studies genetic contributions to this aspect of infant temperament in young twins.
The second is really a set of dimensions relating to emotions. It includes:
Soothability. Some infants are easy to soothe when they’re upset, and a simple hug, a hand on the back, or some cuddling will soothe them. Other infants are very hard to soothe when upset. And some infants are in the middle on soothability.
Fearful distress. Some babies experience a lot of fearful distress and some experience very little.
Irritable distress. Some babies get really frustrated and some babies experience little of this frustration.
Positive emotion. Some babies are super happy, and some less so. I must say, a happy baby, a smiley baby, elicits smiles from the world around her or him. This is an example of what we call an evocative effect—that is, a child’s characteristics evoke certain responses from the environment. We often think that parents influence their children, and this is true, but children also influence their parents. For example, a noncompliant and disobedient child often elicits more harsh punishment and inflexibility in parents (unfortunately, the last thing a child with this kind of temperament needs). As another example, an anxious child often elicits intrusive and overprotective responses in parents (also the last thing a child with this kind of temperament needs). Happily, a smiley baby evokes smiles from the world.
I think you'll find it interesting to listen to at least some, if not all, of the following 10-minute TED Talk by David Rettew, Associate Professor of Psychiatry and Pediatrics at the University of Vermont College of Medicine.


Child Temperament: How We Start to Become Ourselves | David C Rettew | TEDxBurlingtonED

So temperament is what the child brings into the world, and then what happens between parents and children? Well, one very important thing is what we call attachment. Attachment is the emotional bond that forms between caregivers (usually parents) and children. I want to distinguish attachment from the sort of modern idea of what some folks call “bonding.” Some people will say that if you don’t have skin-to-skin contact (bonding) with your infants in the first few days, you will never have a good relationship. I’m here to tell you that that is just simply not true. So don’t believe it. Many children who are born premature or have medical problems have spent months in the neonatal intensive care unit (NICU) at the hospital and are still able to form a very powerful and positive attachment with their caregivers.

Let’s talk about attachment. According to attachment theory, the attachment between the parent and the child will influence the child’s ability to thrive both physically and psychologically. So how do we measure attachment in developmental psychology? We can use something called the Strange Situation, developed by Mary Salter Ainsworth.

The Strange Situation Test
It’s interesting that it’s called the Strange Situation, because it’s modeled after a situation that children frequently encounter—one where they visit a new place with the parent.

Procedure

In the strange situation, the parent and child enter a lab setting and are videotaped. The lab room is set up in a comfortable and inviting way with toys and comfortable chairs, the parent and child enter, and, after a time, the child begins to play with the toys.
Then a stranger enters and tries to engage the child and then leaves; and then the important thing happens.
The mother leaves the child alone in the room!
The mother returns—and this is called the REUNION.
Researchers studying attachment are particularly interested in Steps 3 and 4.  So what happens? Typically, when the mother leaves, the child begins to cry and show distress. What happens when the mother returns? Is this child able to use the mother as a source of comfort, to calm him or herself down and to re-engage and play?

Researchers refer to the mother (or other caregiver) as a “secure base” from which the child can leave to explore the world and to which they can return if they need that security.

So, in the Strange Situation, does the child use the mother as that secure base? The researchers evaluate this based on the child’s behavior.

Using this Strange Situation challenge to examine children’s behavior, researchers have categorized attachment in the following ways:

Secure attachment. In a secure attachment, the infant cries when the mother is away, but is able to use her for comfort when she returns. The child will often run to her, ask to be held, be comforted relatively easily, and soon return to play.
Insecure attachment. In an insecure attachment, the child is unable to use the mother adequately for comfort. There are several different kinds of insecure attachments, and I’m going to describe two:
Avoidant attachment. In this case, instead of using the mother as a source of comfort, the child tends to avoid her when she returns, turning away.
Resistant or ambivalent attachment. In this case, the child seems unable to calm down even in the presence of the mother. The child may appear almost angry at the mother for her absence and unable to move on and return to play easily.
cartoon example of 4 attachement types
Source: Kendra Cherry, VeryWellMind
Take a look at the Strange Situation video, as it demonstrates with real children the use of the Strange Situation to evaluate attachment and shows secure and insecure (avoidant and ambivalent) attachment styles.

Now why is attachment important? Compared to insecure attachments, secure attachments predict more empathic and socially competent behavior in preschool children, and, compared to those with insecure attachments, those with secure attachments are on average more interpersonally skillful, better in school, and have fewer problems in adolescence.

According to attachment theorists, the child internalizes a representation of the attachment relationship, and we call this “an internal working model.” The internal working model is a set of expectations about relationships. When you think about it, your relationship with your caregivers is your first experience of what a relationship is and can be. It sets the stage for future relationships, and that’s your early internal working model. You begin to develop an idea of what you can expect from relationships, including whether you can depend on others, whether others will be there for you, whether others will be predictable, etc. This is not to say that attachment in infancy is 100% predictive. There are some children who may have insecure attachments to parents but later develop close and secure attachments to other individuals in their environment, perhaps a teacher, coach, grandparent, mentor, or other important figure. Attachment is certainly not destiny. You may also wonder if we can form more than one attachment. Yes, absolutely. You may develop an attachment to both parents, a caregiver grandparent, and maybe a preschool teacher. The number of attachments that you can form early on is not unlimited, but it isn’t just one person necessarily.

Cognitive Development

Jean Piaget in Ann Arbor
Source: By Unidentified (Ensian published by University of Michigan) - 1968 Michiganensian, p. 91, Public Domain,
At this point we have talked about physical development and social/emotional development. Along with these we see great changes and increasing sophistication in cognitive development—the mental processes involved in thinking, remembering and processing information. Jean Piaget, a Swiss psychologist, was particularly influential in his theory of cognitive development. Piaget describes cognitive development in the following ways:

Cognitive development is active. Children learn through doing. We can probably all relate to this when we think back to kindergarten and the many activities we engaged in as we were learning about the world. The best ways to teach children are through engaging them actively to illustrate concepts and to have them apply these concepts in their own lives. That’s not just for children! Indeed, in this course when you can come up with an example for yourself to illustrate a concept, you are more likely to understand and remember that concept.
Children go through four distinct stages of cognitive development. I will be describing these in detail below.
Piaget’s theory is a stage theory, and he proposed that children’s thinking was not only greater at each subsequent stage but different in kind. That is to say, the changes between stages are qualitative in nature.

Development: Schemas, Assimilation, & Accommodation

From Piaget’s perspective, children are developing schemas for understanding and exploring their world. These schemas are structures for understanding and organizing information about the world. Schemas are those structures of memory that organize what we know about a particular topic. If we go back to thinking about memory, we know that memory is schema based. When new information is encountered, children try to place that information into existing schemas, and this is what Piaget called assimilation.

However, when the new information doesn’t fit, the child develops a new schema, and Piaget called this accommodation. As an example, an infant has what we would call “a sucking schema” for exploring the world. The infant puts things in her mouth as a means of exploring the world and discovering new information about objects. Any of you who’ve spent time with infants know that almost anything they encounter goes into the mouth—pieces of lint on the rug, other people’s fingers, cat toys (a rather disgusting process at times!). So what if you give an infant a rattle? The first thing that infant might do is to place it in his or her mouth—this is an example of trying to assimilate this new object into an existing schema, the sucking schema. But this really doesn’t work so well, as a rattle is very uninteresting as an object to suck on. Perhaps the child then accidentally shakes the rattle, and, lo and behold, it makes an interesting noise! The child then accommodates, that is, she forms a new schema; we will call it a “shaking schema,” in which objects are shaken to determine how they work. So in this case, the child has tried to assimilate the new information, been unable to do so, and has accommodated by forming a new schema.

Now let’s talk about how children’s cognition changes as they develop.

Piaget’s Cognitive Stages of Development

Source: verywellmind
Sensorimotor Stage

First, is the sensorimotor stage from birth to about age 2. During the sensorimotor stage, which is the first stage of cognitive development, the infant explores his world through sensing and manipulating it. This is how he acquires knowledge. He may look at the object, smell it, touch it, move it around, push it back and forth, and figure out how it works. For example, if he encounters a ball, he may first try to place it in his mouth, turn it around and over, and eventually try to roll it. Piaget believed that children were little scientists trying to figure out the laws governing the world they live in. I think of the child during this stage of development as a young physicist trying to figure out the laws governing objects. The 1-year-old will happily push over her sister’s block tower and scream with delight as she watches the blocks fall. She’s figuring things out.

One of the major accomplishments of the sensorimotor period, according to Piaget, is the development of what he called object permanence—the idea that objects continue to exist even when hidden or no longer apparent. When the very small infant drops his pacifier under his covers, he may not look for it, as he does not recognize that it still exists. During the sensorimotor stage, he begins to realize that objects still exist even when they are no longer apparent, and he will begin to search for the missing pacifier. He has come to an important cognitive understanding about the way the world works. Objects exist even if we don’t see them any longer.

Preoperational Stage

The next stage of cognitive development is the preoperational stage; it lasts from approximately age 2 to age 7 where the child and begins to demonstrate what Piaget referred to as “pre-logical” thought processes. This stage is characterized by the following:

Symbolic thought. During this stage we see the beginning of symbolic thought as children develop the ability to use words, images, and symbols. Indeed, we see impressive gains in language, and we also see the use of fantasy and imagination during play. The child may make a “cake” out of dirt, leaves, and mud, bring it to you, and ask, “What do you think of my cake?” Now of course the child knows that you are not going to actually eat this cake! He realizes that this mess is not something you would want to eat. This mud cake is a symbol of a real cake. And, if you are good with children, you will play along and say something like, “Wow, I love your cake, what flavor is it?” Children engage in all kinds of representative play, where one object represents something in the real world.
Egocentrism. During this stage we also see the children are often egocentric. When I say this, I don’t mean that there are egotistical or mean. They just have a hard time taking another person’s perspective or point of view. They are only able to see things from their vantage point. Think of the child who is asked to talk on the phone to her grandmother, and she may say, “Hi Grandma, isn’t my doll pretty?” Now of course Grandma cannot see the doll. (Grandma is on the phone after all.) The child is egocentric and has a hard time taking the grandmother’s point of view; she assumes that because she herself can see the doll, the grandmother must be able to as well.
Irreversibility. According to Piaget, the child during the preoperational stage also exhibits irreversibility—she cannot reverse a sequence of events. For example, teaching a child subtraction at this stage is very difficult. Subtraction involves reversing a sequence of events (addition).
Centration. The child also exhibits centration during the preoperational phase. Centration is the tendency to focus or center on only one dimension of the situation at a time and ignore other important aspects of the situation Piaget demonstrated this through conservation experiments. Conservation is a set of understandings that quantity, number, mass and other physical dimensions remain the same even when their form or appearance is rearranged, so long as nothing is added or subtracted. See the video for a demonstration of conservation.
cas_ps101_19_su2_mtompson_mod4_conservation video cannot be displayed here. Videos cannot be played from Printable Lectures. Please view media in the module.
Concrete Operational Stage

The next stage of cognitive development is the concrete operational stage, lasting from about age 7 through age 11. During this stage of development, the child is able to think logically about concrete objects and situations but she’s not able to consider abstract ideas. What do we mean by “concrete”? Concrete thinking is focused on real, observable phenomenon. For, example the concrete operational child can use logic to understand how to put objects together or take them apart; she can comprehend how a machine works; he can use the scientific method to fix a problem (holding all aspects constant and manipulating only one at a time). She can do those conservation tasks with relative ease. What do we mean by “abstract”? These are ideas that cannot be readily observed and have to be inferred—justice, freedom, etc. Children in the concrete operational stage can’t really understand such ideas (except in concrete terms; for example, “justice” is making sure you get as big a piece of cake as the other person). Remember though that these skills emerge over time, and the exact timing may be different for different children and different tasks.

Formal Operational Stage

The next and final stage of cognitive development according to Piaget is the formal operational stage. This lasts from adolescence through adulthood, and during this stage individuals are able to think logically about abstract principles and hypothetical situations and generalize from specific examples to other situations. It seems that this period of cognitive development may emerge gradually.

Criticisms of Piaget

Although Piaget’s theory has been hugely influential, it has also been criticized. Here are some of the main criticisms:

Piaget may have underestimated the abilities of children and infants. Sometimes Piaget confused motor competence with cognitive competence when he was assessing object permanence during infancy. Perhaps children knew more than they were able to demonstrate from a motor standpoint. As an example, later investigators who used different types of tasks (ones that rely less on motor abilities) found that infants may develop object permanence far earlier than Piaget had initially indicated.

Piaget suggested that his stages were universal, but this may not be quite true. Many adults may not display abstract thinking that he said was characteristic of the formal operational stage. Indeed, many of us only display formal operational thinking in areas where we have a lot of knowledge and expertise. For example, an English major may be able to discuss literature using abstract principles but may not be able to think of a physics problem in an abstract way. Alternatively, the physics major may be able to think abstractly about the nature of the cosmos but may not be able to discuss the underlying meaning in a particular work of fiction. Nowadays many developmental psychologists focus on an information-processing model of cognitive development, which emphasizes the continuous changes in cognitive development that occur over the lifespan. They may focus on understanding mental processes including attention, memory, and problem solving.

Piaget emphasized cognitive development as a process of maturation, and he may have underestimated the important impact of the social and cultural environments on children’s cognitive advances. Cross-cultural studies suggest that cognitive development may be strongly impacted by cultural values.

Language Development

One of the major developments throughout childhood is the growth in language. Children go from not talking to being big talkers! How does this occur? In many ways, language is the ultimate representational (or symbol) system that children acquire. In language, words represent objects, actions, ideas, etc. How do we learn language? Many people would respond by saying that children imitate others, and certainly that is part of it. But I would argue it is much, much more complicated than that, so let’s talk about language development.

Major Characteristics of Language

Human language is unique. Yes, we can teach chimpanzees to use sign language, but I would argue that they can only learn a limited number of words and it is certainly a labor-intensive process. On the other hand, human children “pick up” language along the way. How they do this is pretty amazing.

Here are some of the defining characteristics of human language:

It’s creative. That is, you use it in new ways all the time. You say things that you’ve never heard before (so the idea of imitation is not really adequate as an explanation for language development).
It’s structured. Most times we are not even aware of the deeply embedded structure of language. We obey lots of rules. I’d like to distinguish between prescriptive rules of language and the descriptive rules of language. Prescriptive rules are those that we are aware of and allow us to speak the language “properly.” These rules include avoiding the word “ain’t” and never ending a sentence with a preposition. So if you want to speak the Queen’s English, obey the prescriptive rules!! On the other hand, descriptive rules are those that any ordinary speaker of the language follows. These rules describe how language is actually used, and these rules are often far out of our awareness—I’ll demonstrate that later!
It’s meaningful. It helps us convey concepts to one another.
It’s referential. It allows us to reference happenings in the past and future; it allows us to communicate about objects and people that aren’t even present (or maybe never existed!).
It’s interpersonal. We engage in language in an interpersonal context to communicate our meaning with others. This is not to say that we always and only use language with others. How many of you have been known to talk to yourselves? Don’t be embarrassed! Most folks do this. Sometimes I smile when I drive by someone who is completely alone in the car and is talking a mile a minute. Of course, I have been that person . . . We talk to ourselves as we figure out a problem aloud, as we rehearse what we are going to say to someone else, as we remind ourselves of things we need to do. No shame in talking to yourself! On the other hand, most of our language is used to communicate with others.
Language Structure

Before we can talk about language development, we need to know something about its structure. Here’s a hierarchy of language:


Phonemes. These are the individual sounds of language, and there are about 40 in English. Many languages contain unique phonemes—ones that are not present in all languages.
Morphemes. You can start to put these phonemes together into meaningful chunks. There are two types of morphemes: content and function. Content morphemes carry the bulk of the meaning; function morphemes add details to that meaning. Let me give you an example. Take the word “workers.” It has three morphemes—three meaningful chunks. The first is “work”; it is a content morpheme as it carries a lot of meaning. We all know what “work” means. The next morpheme is “er”; it is a function morpheme. In English when we add “er” we make it clear that we are talking about a person who does the thing—a “worker” is a person who does the work. The next morpheme is “s”; it is a function morpheme. In English this one tiny letter conveys a lot of information—it tells us that there is more than one of them. In this case, “workers” means that there is more than one worker. It indicates the plural. The word “workers” contains three morphemes—one content and two function.
Words. These are just collections of morphemes.
Phrases. These are just collections of words.
Sentences. These are just collections of phrases.
Now we could go on if we wanted to talk about written language, but for our purposes we are going to focus on spoken language.

Spoken Language

Now that we know about language structure, let’s focus on some theory.


Noam Chomsky on Language Development


Noam Chomsky was a linguist who put forth the idea that human children are born with an innate predisposition to learn language—it’s a basic instinct. He referred to a “universal grammar” or an inborn understanding of how language works and how children are predisposed to extract both the meaning and the structure of language through exposure. This is a Nativist approach (we are born with it), and some would say it ignores potentially important environmental contributions . . . so we’ll get back to Chomsky. Let’s talk about some environmental happenings that may support language.

In many situations, adults and older children talk to infants in a particular kind of way, and this type of language has come to be known as “motherese” or “infant-directed speech”—I prefer that latter label, as not just mothers are doing this.

In this type of speech, when we speak to infants we use distinct pronunciation, a simplified vocabulary, a high-pitched tone, lots of repetition, and exaggerated expression and intonation. You all probably have a pretty good idea of what I’m talking about here! It’s funny when you see people doing this with their dogs and cats (i.e., their babies!). The truth is that infants seem particularly drawn to this kind of speech. What infant-directed speech does is to make it easier for babies to decode the complexities of language. One important point: Babies do not learn language through TV! They learn while interacting with others. We also see babies and their caregivers interacting in games that encourage vocal imitation. Just one caveat—not all cultures use this infant-directed speech. . Hmm. Yet these children still learn language . . .

There are other types of important interactions with caregivers that are happening throughout early development and that support language learning. They include:

Shared Attention. From early on it is essential that babies begin to be able to share attention with caregivers. When the caregiver points to an object, the typically-developing baby looks at what is being pointed to. Over time, the infant will begin to follow the caregiver’s gaze—to look at the same thing the caregiver is looking at. Thus, the focus of attention for both is the same—that’s essential for learning from others.
Comprehension vs. production. Any of you learn a new language? If so, you know that your ability to understand language proceeds your ability to produce clear sentences. That’s true with children as well. I remember getting ready to go to the park with my 15-month-old son. He could say “mama” and that’s it. I’m running around the house looking for his sippy cup and saying, “Now where did I put that cup!?” Next thing I know he comes up and says “Mama” and hands me the cup! Wow! His production was limited, but his comprehension was pretty good. Comprehension comes before production.
Turn-taking. When we use language, we take turns. I talk for a bit, then you talk, then I talk, etc. We learn to let others “take the floor,” and at times we “take the floor.” Please don’t be the kind of person who holds the floor and just talks and talks and never gives anyone else their turn! Ugh! Pre-verbal children take turns with their caregivers—the child says “Bah Gah Gah,” and the parent takes a turn, “Bah Bah Bah”, and so on.
My point here is that these are prerequisites to language—then when the language finally comes, it can just “drop in” to these previously established communication skills.

So how does language emerge? What are some of the milestones of language development?


Developmental Milestones: Baby Talk from First Sounds to First Words


In early infancy, babies cry to communicate their needs. This is super effective! Nothing makes adults come running like hearing a baby cry—you want to figure out what’s causing the crying and fix it fast. Over time parents can begin to recognize distinct cries that mean “I’m hungry,” “I need a clean diaper,” “I’m tired,” “I want to be held,” etc. Interestingly, during this time babies are able to distinguish between the phonemes of all languages! They can distinguish the English phonemes, the Japanese phonemes, the Swahili phonemes, etc. They can do it all. They can hear the difference between, say, “bah” and “pah.”

At about 3 months of age the baby begins to coo. . . so cute! Cooing is composed of long vowel strings. It’s adorable but slightly disruptive when done loudly in a quiet restaurant setting. The baby is practicing making sounds.

At about 5 months of age the child begins to babble. Babbling is practicing using different phonemes and at this age babies babble using phonemes from all different languages. The child is a generalist—practicing skills that will allow them to learn any language!

At about age 9 months the child begins to narrow their babbling to just those phonemes that are present in the language(s) they are being exposed to. The child is now becoming a specialist! He or she will be ready to learn the language of his/her own people—French, Swahili, Tagalog, any other.

Methods

Now you might wonder how it is we know what babies do and don’t know. It’s a really good question. How we figure this out? Well one way is by using what’s called a habituation paradigm. A paradigm is an experimental strategy or approach. As you will recall from our learning chapter, habituation is a process whereby individuals stop responding to a repeated stimulus. When a baby notices something new in his or her environment, that baby responds. One thing a baby will do when they hear something novel is to begin sucking more rapidly. As he or she habituates, the rate of sucking behavior decreases. So here’s how a habituation paradigm to study children’s recognition of new phonemes might work. Look at the graph in this slide.

abituation paradigm
The researcher could play a recording of a phoneme being repeated over and over again, for example “Bah, bah, bah.” At first, when the baby hears this recording of a new sound, the rate of sucking will increase. After a while the baby habituates to the sound, and the rate of sucking then decreases. Then the researcher could play a recording of a new phoneme being repeated over and over again, for example, “pah, pah, pah”. If the baby’s rate of sucking then rapidly increases, we know that the baby can recognize the difference between “bah” and “pah” (after all, “pah” is new information!). We can’t ask the baby what he or she knows, but we can use his or her behavior to give us some very powerful information.

At about 1 year of age children begin to say their first actual words. The first word is usually a person, activity or concrete object—“mama”, “bye bye” or “ball” might be examples. They are not likely to use a verb like “throw” or “be”. They then begin to add single words. They overgeneralize meaning here at times—they apply a new word to inappropriate instances. For example, once they learn the word “doggie”, they may label any furry four-legged creature as “doggie”; however they soon learn that only the domestic canine is really a “doggie”.

At about age 2 children begin to combine words to form telegraphic speech—speech that is devoid of connecting words like conjunctions (“and”), prepositions (“of,” “with,” etc.), or articles (“an,” “the,” etc.). They combine these words with gestures to communicate pretty clearly. They may say “more milk,” meaning “I’d like you to give me more milk,” or “throw ball,” meaning “I’m going to throw the ball.” Notice here that they are using correct word order—and we see that throughout this period of development. It seems that child is already learning something about the structure of language!

By 30 months of age children show a rapid increase in language and longer utterances—they are learning fast, and they still use appropriate word order. They also use proper verb forms—“I ate my lunch.”

Around age 4 or 5 something weird happens—they begin to make mistakes! They used to say “I ate my lunch” but now they say, “I ate my lunch,” but now they say, “I eated my lunch.” They used to say, “I held the puppy,” but now they say, “I holded the puppy.” Oh no! Why are they messing up? Actually, this is evidence that they are learning something about the deep structure of language. In English, the past tense for regular verbs is obtained by adding “ed,” so “jerk” becomes “jerked,” “ask” become “asked.” The child has learned this and begins to overgeneralize this rule to situations where it doesn’t apply (irregular verbs)! Now if you ask the child why they are doing this, they won’t know. We do know that parents aren’t teaching the rule. Eventually they stop overgeneralizing and use the correct verb tense. This really does illustrate how children are learning language rules from hearing spoken language, and they don’t even know it’s happening.

Chomsky was right—children do have an inborn predisposition to learn language, and often this ability is supported by the environment. However, this process really applies to learning language structure and meaning. There’s a lot more to language! As one example, how do children learn to say “please” and “thank you”? Parents consciously teach this to children! We are not innately driven to be polite! Our parents teach us this. Also, there are some powerful differences in how boys and girls are exposed to language. Parents tend to talk to girls more and use more emotion words (e.g., “sad,” “happy,” “excited,” etc.). Parents tend to use the word “no” more with boys—even in the crib! It looks like boys and girls are socialized according to gender starting very, very early. Are parents aware that they are doing this? NO. Parents will often be completely unaware—they are doing this unconsciously.

Disorders of Language

So what happens when it all goes wrong? And what does this tell us about brain regions involved in language? An aphasia is a severe language impairment. People can experience aphasias for a number of reasons. In some instances, an individual experiences a stroke—an area of the brain where blood flow is cut off leading to damage. Studies have demonstrated that damage to an area in the brain known as Broca’s area leads to what is known as an expressive aphasia. Broca’s area is in the back part of the frontal lobe of the left hemisphere of the brain. In this Broca’s aphasia, the individual has tremendous difficulty in producing words, reading, and writing. I remember this by noting that Broca’s aphasia leads to “broken language.” These individuals may understand well but have trouble communicating. Here’s a video of a man with Broca’s aphasia:

Broca's Aphasia (Non-Fluent Aphasia)

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Damage to an area in the brain known as Wernicke’s area leads to what is known as a receptive aphasia. Wernicke’s area is in the rear part of the temporal lobe where it connects to the parietal lobe. In Wernicke’s aphasia, the individual has difficulty understanding language, even their own; he or she may speak fluently but make little sense. Here’s a video of a man with Wernicke’s aphasia:

Fluent Aphasia (Wernicke's Aphasia)

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Additional Areas of Development I Want You to Understand for the Exam

If you haven’t yet read it, you will notice that chapter 8 is a long one! There’s a lot of information there. In terms of chapter 9, there are only a few things I want you to remember. These are:

The difference between fluid and crystallized intelligence and how this changes from young adults to older adults.
Facts about puberty:
This is the period of change where children begin to develop secondary sex characteristics (e.g., growth of genitalia, increase in body hair, breasts and menstruation in girls, facial hair and lowering of the voice in boys, etc.). This is when you go from being a child to being an adult.
Puberty can take several years to complete.
It is associated with many neurological changes—decrease in dopamine in certain regions, increase in myelination of neuronal axons.
It starts, on average, earlier for girls than boys. Think about the early middle school years when girls get taller and more “woman-like” and boys are often still short and “boyish.”
It can begin at a range of ages—some kids start earlier than others.
Early puberty can be associated with increased risks for girls (e.g., school dropout, precocious sexuality, early pregnancy, etc.). It’s less clear for boys—some studies suggest advantages (it’s good for sports performance, for example) and others suggest disadvantages.
Now let’s talk about another stage theory! It’s the stage theory of moral development.

Moral Development

Lawrence Kohlberg was an American psychologist interested in the ways in which our thinking about right and wrong change with age. How do we develop our moral thinking? Kohlberg devised a series of moral dilemmas that typically involved a choice between two alternatives, both of which would be considered generally unacceptable by society’s standards.

He described to his subjects the following dilemma, known as the Heinz dilemma:


What:
Kohlberg wouldn’t be interested in whether you thought Heinz was right or wrong.
He was interested in the process you used to reach your judgment; your reasoning would indicate how advanced your moral thinking is.
Kohlberg asked his subjects a series of questions about each moral dilemma and then used a complex scoring system to assign a subject to a particular category or stage of moral reasoning.
He then developed a theory of moral development in which he proposed that we move through 6 stages of moral reasoning with 3 basic levels: preconventional, conventional, and postconventional.
Let’s focus on the preconventional level:

Children ages 4–10
Self-serving approach to morality
Stage 1: avoid punishment. For example, “Heinz should steal the drug because if his wife dies, he’ll get in trouble.”
Stage 2: get rewards. For example, “Heinz should steal the drug so she can still be alive and keep him company.”
Children haven’t internalized a personal code of morality yet.
The next level is the conventional level:

Late childhood–early adolescence
Stage 3: desire to help others and gain their approval. For example, “Heinz should steal the drug to help his wife feel better and for other people to know he’s a good person.”
Stage 4: help maintain the social order. For example, “Heinz shouldn’t steal the drug because it’s against the law; laws allow people to live together and resolve conflicts.”
Begin to internalize moral standards of adults
The final level is the post-conventional level:

Stage 5: affirms values agreed on by society including individual rights and the need for democratically determined rules. For example, “Heinz shouldn’t steal the drug because rules are essential in a democratic society to maintain the rights of individuals who have made sacrifices to develop new drugs.”
Stage 6: individuals are guided by universal ethical principles in which they do what they think is right as a matter of conscience, even if their acts conflict with society’s rules. For example, “Heinz should steal the drug because respecting human life supersedes the profit motive and is the higher moral principle.”
It’s not whether you think the act is right or wrong, it is the reasoning one uses to arrive at that conclusion.
Kohlberg thought only about 25% of adults in our society progress beyond Stage 4, and that most of these individuals do so sometime during their adult years.

Kohlberg's Stages of Moral Development

There have been a number of critiques of Kohlberg’s theory of moral development, including:

A high level of moral reasoning does not necessarily go hand-in-hand with moral actions, especially if a person is under strong social pressure
Carol Gilligan argues that Kohlberg’s stage theory, which was based on male participants, ignores critical differences between the sexes in social and moral understanding
For example, in a research study, she compared men and women’s thinking about real-life dilemmas, such as abortion. Men tended to focus on issues about justice while women tended to focus on issues about care of others.
Can you think of other possible critiques?
Let’s think of a “real life” application of Kohlberg’s moral stages:

You are home for the summer hanging out with your friends from high school at a party where your best friend is going to introduce you to her new boyfriend. Your friend has told you she’s totally in love and you are excited to meet him. As soon as she introduces you, you recognize him and realize that he is the same guy who is also spending “quality time” with a friend of yours from college. Your best friend has no idea and would be really upset to find out he was cheating on her. Do you tell your best friend what you know about him and risk your friendship with her? Do you let it play out naturally and not say anything? Or, do you say something to the boyfriend without proof?

What would you do? What might someone think if they were using pre-conventional moral reasoning? How about conventional moral reasoning? How about post-conventional moral reasoning?

Methods in Developmental Psychology

What are some of the ways that we study development? I’m going to compare two different types of research designs that are used in developmental psychology.

Cross-Sectional Design

In a cross-sectional design, we look at different groups of children at different ages. For example, let’s say I want to understand how 6-month-olds and 9-month-olds differ on object permanence tasks. I could recruit 30 six-month-olds (and their parents, of course) and 30 nine-month-olds (and their parents) and examine their performance on these tasks. This would be an example of a correlational study in that I’m examining the relationship between age and object permanence. As another example, let’s say I want to understand the impact of two different methods for teaching addition on children’s memory for addition concepts. I could recruit, say, 200 children and randomly assign half of them into method A and the other half into method B. I could then do an immediate posttest to evaluate how much they remembered of the math concepts. This would be an experimental study (it’s experimental because I, the experimenter, “manipulated” the independent variable – the teaching method).

There are a number of advantages to the cross-sectional design. Given that I only have to test the children once, it is easy, quick, and relatively inexpensive. I can compare my groups and have an answer to my question. On the other hand, there are disadvantages. In the correlational design, I cannot determine precisely when the particular skill (object permanence) emerged. In the experimental example, I do not know if the differences I’m seeing would stand up over time. The cross-sectional design is really a snapshot on development, much like taking a picture at one particular moment.

Longitudinal Design


Closer: Longitudinal studies: an overview

In the longitudinal design, I follow a group of participants over a longer period of time. What I can do here is examine change over time, and that is not something I can do in a cross-sectional study. For example, let’s say that I want to examine how boys and girls differ in their development of friendships during middle school. I could select a group of middle school boys and girls and follow them for the three years of middle school, conducting regular evaluations (maybe every six months) of their friendships. This is an example of a correlational study. As another example, let’s say that I want to examine two different methods for teaching school children reading. I could recruit a sample of say 200 elementary school children and randomly assign half of them to one reading curriculum and half of them to a different reading curriculum. They could then undergo the reading curricula and I could follow them over time to see how reading is impacted across the elementary school years. This is an example of an experimental study.

There are many advantages to a longitudinal design. For one thing each individual is followed, so I can control for individual differences (in some ways each as their own control). Second, I can examine how people change over time. However, there are also downsides to the longitudinal design. One downside is that it’s pretty expensive to conduct such a study. These expenses include money, time, and other resources. A second downside is that we can have problems with attrition. Attrition is a loss of data over time due to the fact that not all participants will agree to continue to participate in the study. This is a real problem. How do I know that those who participated over time are the same as those who didn’t participate? Is the sample that is retained generalizable to the sample that was lost? In doing longitudinal research it is essential to try to maintain your sample and not lose participants. The other thing that can happen that can present a real problem is if some important completely unplanned event takes place in the middle of your study. Let’s say that in my example of studying student friendships, halfway through my study a new middle school opens and half of my participants are sent to the new middle school! Oh no, that really disrupts student's friendships, so what happens to my study? Or take the example of my reading intervention. Let’s say I did my reading intervention and I began following up with the kids to see how they did. Then suddenly the school district decides to implement a new reading protocol to enhance reading for all students. Oh no! How does this impact what I learn about my reading intervention?

So you can see that doing a longitudinal study can be quite tricky.

Comparison Table of Cross-Sectional Design vs. Longitudinal Design

Cross-Sectional	Longitudinal
One point in time	Several points in time
Different samples	Same samples
Snapshot of a given point in time, change at a societal level	Change at an individual level
Example: Cross-sectional studies of personality in a national sample	Example: The Seattle Longitudinal Study, a study of adult development from midlife through old age that has followed a panel of people since 1956.
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