Human Sexuality

Chapter 10

Childhood Sexual Development

How do we grow into sexual beings? Following sexual development from before birth through the end of adolescence.

Ask most people when human sexuality "begins," and they will point to the teenage years. Puberty arrives, hormones surge, and a child suddenly turns into a young adult with romantic and sexual feelings. In real life, though, sexual feelings and urges begin far earlier.

Sexuality is not a switch that flips during puberty. It is a slow, lifelong process that starts before we are even born. Doctors have watched male fetuses have erections and even self-stimulate their genitals while still in the womb (via ultrasound; Martinson, 1994). Newborns show reflexive sexual responses: baby boys have erections and baby girls produce vaginal lubrication in the first days of life (Martinson, 1994). None of this means infants have sexual thoughts or desires in the way adults do, but the body's capacity for sexual response is present from the very start of life.

Why, then, do we cling to the idea that children are asexual — that is, entirely without sexual feeling or response? Part of the answer is discomfort. The sexuality of children is a subject that makes adults uneasy. We want to protect children, and acknowledging them as sexual beings can feel dangerously close to sexualizing them. But protecting children and understanding them are not at odds. The more we know about how children grow and develop, including sexually, the better we can be at making sure we support them through all aspects of development. From conception until death, humans are sexual beings, and the childhood years are among the most important in shaping who we become.

An idealized illustration of a young child depicted as an innocent angel. — **Figure 10.1.** Western culture has long imagined childhood as a time of pure sexual innocence — a comforting image that research does not fully support.

One caveat before we dig in. Directly observing children's sexual behavior is both rare and ethically impossible to arrange. As a result, most of what we know comes secondhand, from parents, teachers, and caregivers who report what they have noticed (Friedrich et al., 1998). Still, the picture that emerges is remarkably consistent across reporters, which allows us to draw firm conclusions about how kids mature. In this chapter, we'll follow children's sexual development from the first months of life through the end of adolescence.

10.1 The Many Dimensions of Sexual Development

One idea runs through this whole book: sexuality is about far more than genitals. When we talk about a child "developing sexually," we are not only talking about bodies and body parts. Sexual development includes a whole set of changes — in how children think, how they connect with others, how they understand gender, and how they experience pleasure. It helps to pull these apart and look at them one at a time. Researchers often describe sexual development along five dimensions, meaning five separate strands of growth that develop side by side.

The cognitive dimensioni is the growth of a child's mental understanding of sex. A two-year-old and a ten-year-old "know" wildly different things about where babies come from, what bodies are for, and what the word sex even means. This understanding develops right alongside language and a sense of burgeoning identity. As thinking matures, so does a child's ability to grasp more complex and abstract ideas about sexuality.

The social dimensioni is the degree to which a child's experience of sexuality begins to include other people. For a newborn, the important "other" might be a warm blanket or the comfort of being held. For a school-age child, it might be a same-gender friend or a first crush. For an adult, it becomes a romantic or sexual partner. Over the years, sexuality moves from being something a child experiences alone to something experienced with and through others.

The gender dimensioni is the way our recognition of gender develops, including our own and other people's. At birth, a baby has no concept of "boy" or "girl." Within the first year, infants start to notice differences. By early childhood, gender becomes one of the main categories children use to sort and make sense of others. For most people, ideas around gender grow richer and more flexible with age. Young children often heavily endorse gender stereotypes, such as almost universally drawing doctors as men and nurses as women (Stephens et al., 2016). This is based largely on first-hand experience and noticing patterns common in their culture. But, as we mature, most of us come to recognize and (hopefully) confront such ideas as inaccurate and harmful.

Children's drawings in which doctors are consistently drawn as men and nurses as women. — **Figure 10.2.** Asked to draw a doctor and a nurse, young children overwhelmingly depict the doctor as a man and the nurse as a woman — a vivid sign of how early gender stereotypes take hold (Stephens et al., 2016).

The orientation dimensioni, tied with sexual orientation, is how we come to recognize whom we are attracted to and how we develop the capacity to form romantic and sexual attachments. Orientation unfolds gradually. It shapes an important part of our eventual sense of who we are, but the age at which people first become aware of it varies enormously from one person to the next.

The erotic dimensioni is how we come to experience and interpret pleasure itself. Do we associate physical pleasure with joy or with guilt? Do we seek pleasure in our connections with others or prefer to pursue pleasure by ourselves? A great deal of the erotic dimension is written early, in the countless small moments when a caregiver responds to a child's body and curiosity — with warmth or with shame.

These five strands do not develop in isolation. They twist together, each one influencing the others. A child who is taught the real names for body parts (a cognitive step) and whose caregivers respond warmly to natural curiosity (an erotic and social step) is laying the groundwork for healthy sexual development to come. In the sections that follow, we will use these five dimensions as a lens, watching how each one changes as a child grows from a newborn into a young adult.

Four labeled 3D ultrasound images of a male fetus, identifying the penis, glans, foreskin, and a fetal hand. — **Figure 10.3.** Labeled 3D ultrasound images of a male fetus. Clinicians have documented fetal erections and what appears to be self-touching in the womb (Meizner, 1987).

Multiple Choice

A parent notices their four-year-old carefully sorting toys into "boy toys" and "girl toys" and announcing which ones are "not allowed" for the other group. Along which dimension of sexual development is this child most clearly showing growth?

AThe erotic dimension

BThe gender dimension

CThe orientation dimension

DThe cognitive dimension

10.2 From Infancy Through Preadolescence

Sexual development from birth into young adulthood is best understood in stages. At each stage, all five dimensions are changing at once. We will walk through three broad periods — infancy, early childhood, and preadolescence — and see how a child's body, mind, and experience of pleasure shift along the way.

Before we start, one piece of history is worth knowing, because it explains a lot about how modern families handle these years. Before the nineteenth century, children in most places grew up close to the raw facts of life. They often slept in the same room as their parents, which meant occasional glimpses of adult intimacy. Many lived on farms, where animals mated, became pregnant, and gave birth in plain view. In warm weather, young children often ran around undressed and saw other children's bodies without any sense of shame or secrecy. During the 19th century, a new belief took hold: that childhood should be a protected time of sexual innocence. That belief is still with us. Many children grow up inside what researchers have called a conspiracy of silencei — an unspoken agreement among the adults around them to never discuss sex openly. Most children in the U.S. rarely talk with their parents about sex, rarely see their parents naked, and never see sex for themselves.

A parent and child sitting in awkward silence, unable to talk openly about sex. — **Figure 10.4.** The modern "conspiracy of silence" — an unspoken agreement among adults never to discuss sex openly — teaches many children that sexuality is a shameful topic.

Is that silence protective? The research suggests it is not especially helpful, and that the fears behind it are mostly unfounded. Some clinicians once worried that a child seeing a parent naked, or catching a glimpse of parents having sex, would be harmed by the experience. Careful study does not bear this out. In fact, one line of research found that adults who had, as children, seen their parents having sex reported fewer sexual problems later in life (Okami et al., 1998). Whatever their level of exposure, most young children are naturally curious and full of questions. "Where do babies come from?" "Why are my genitals different from theirs?" "Why does it feel good when I touch my genitals?" The range of how adults respond — with honesty, secrecy, or a fairy-tale version of reality — teaches children their very first lessons about sex.

Infancy (Birth to Age 2)

For an infant, the whole skin surface is, in a sense, an erogenous zone. Babies experience a powerful need for comfort contacti, meaning warm physical touch that soothes and reassures them (Martinson, 1994). A baby explores the world, and its own body, through touch and movement, slowly learning which sensations feel good and which feel bad. Cuddling, feeding, and a warm bath land on the "good" side, while a wet diaper and an empty stomach land on the "bad" side.

A young toddler standing indoors, holding a sippy cup and exploring the world through touch. — **Figure 10.5.** In infancy, ordinary exploration of the body through touch is a normal source of comfort and self-soothing — with no sexual meaning to the child.

Along the way, ordinary tactile exploration sometimes drifts into what researchers call unfocused masturbationi — self-touching of the genitals that produces a pleasant feeling (Friedrich et al., 1998). It is crucial to understand what this is and is not. The infant has no cognitive ability to give the behavior sexual meaning. A genital response is simply lumped in with other good feelings, part of a general pattern of behavior that gives pleasure. Reflexive erections and vaginal lubrication can be triggered by all sorts of ordinary things: the rhythm of a moving car, the warmth of sand, a diaper change, or even a burst of excitement or fear. These responses are not signs of adult-style desire. They are reflexes — part of a generalized arousal response that has nothing to do with sexual intent.

The social dimension in infancy is defined by total self-centeredness. Early psychologists used the term egocentric, which means the infant experiences their caregivers less as separate people than as extensions of themselves. What infants crave, above all, is comfort contact, and children quickly figure out what behaviors get them what they need, such as crying or wriggling toward a warm body. When children are persistently deprived of comfort contact, the consequences can be serious and lasting. The attachments an infant forms with caregivers set a pattern for future relationships and for how the child will experience closeness and sensuality. We'll discuss this in more detail later in this chapter.

Gender is developing too, earlier than most people assume. It is a common mistake to think infants have no sense of gender at all. In a well-known set of studies, the psychologist Paul Quinn found that babies as young as 3 months could tell male and female faces apart, with most infants showing a preference for female faces (Quinn et al., 2002). This preference seemed to have to do primarily with who gave them the most comfort. When Quinn's team looked at babies raised mainly by fathers, the preference flipped toward male faces.

Even at this early age, the adults around a child shape gender development by how they treat sons differently than daughters. Research finds that parents, and fathers in particular, tend to coo, cuddle, and use baby talk more with daughters, treating them as more fragile, while using more grown-up speech and rougher, more physical play with sons (Halpern & Perry-Jenkins, 2016; Berk, 2009). Fathers who roughhouse just as happily with their daughters tend to raise children with less rigid ideas about what boys and girls are supposed to be.

The orientation and erotic dimensions are simpler in infancy. In terms of orientation, infants orient toward the familiar — a known voice, a known face, a known smell. Erotically, pleasure is reflexive and relaxing, handled with pure pragmatism: if it feels good, seek more; if it feels bad, stop. Over these first two years a body mapi begins to form, meaning a rough sense of which parts of the body feel good and which feel bad (Martinson, 1994).

An illustration of a baby exploring its own body through touch. — **Figure 10.6.** Through everyday touch and exploration, infants slowly build a "body map" — a rough internal sense of which parts of the body feel good and which feel bad.

Multiple Choice

A new parent is alarmed to notice that their infant son sometimes has an erection during a diaper change. Based on what we know about infant development, the best explanation is that this is:

AA sign of premature sexual development that needs medical attention

BA normal reflexive response with no sexual meaning to the infant

CEvidence that the child has been exposed to something inappropriate

DA deliberate attempt by the infant to seek sexual pleasure

Early Childhood (Ages 2 to 8)

The early childhood years are when sexuality becomes visibly social and curious. Many parents still fear that a child who sees a naked adult body will be traumatized. The evidence points the other way: seeing ordinary nudity helps children grow comfortable with their own bodies and learn about anatomical differences between the sexes (Okami, 1995). Around this age, natural curiosity about bodies and where babies come from blossoms into a steady stream of questions.

The typical behaviors of this stage are gentle and exploratory. Kissing, hugging, and stroking are common. Children may start undressing and showing their bodies to others. Games like "playing doctor" or "let me see yours, and I'll let you see mine" become popular. About half of parents report noticing this kind of sex playi — children showing or touching one another's genitals out of curiosity (Friedrich et al., 1998). It is important to note that such play reflects curiosity and imitation of adult roles far more than any sexual interaction in the adult sense. Children are learning about bodies and trying on grown-up roles. Caregivers who stumble onto such play don't need to overreact by shaming or punishing their curious children. Instead, such instances present a good opportunity to teach kids healthy boundaries around their bodies and how to interact with others.

Two young children showing affection while playing together. — **Figure 10.7.** Curiosity-driven "sex play," such as playing doctor, is reported by about half of parents. It reflects exploration and imitation of adult roles far more than any adult-style sexual interaction.

True masturbation also appears in this stage, arising spontaneously and experienced simply as a form of self-pleasure. According to surveys of parents, roughly 60% of boys and 45% of girls have begun masturbating before age six, with behaviors ranging from manual touching to rubbing against furniture (Friedrich et al., 1998; De Graaf & Rademakers, 2006). Yet what parents report varies dramatically by country. The vast majority of mothers in Europe say they have seen their young child touch their genitals, but only about half of U.S. mothers report the same, most likely reflecting greater European openness about childhood sexuality rather than any real difference in children (Larsson et al., 2000; De Graaf & Rademakers, 2006). Behind the American reluctance often sits a misguided fear that masturbation is harmful or improper, especially in children (Klass, 2018). Pediatricians usually reassure parents that the behavior is normal, though they less often offer concrete guidance on how to handle it, and girls in particular tend to be left out of these conversations altogether.

What about more involved sexual play? One study asked young adults in the United States to recall the voluntary sexual activities they had engaged in with other children between the ages of 6 and 10 (Larsson & Svedin, 2002). Talking about sex, kissing and hugging, and showing one's genitals were all fairly common. However, only very small percentages remembered any voluntary penetrative activity. In other words, curiosity-driven looking and touching is a normal part of childhood; penetrative sexual acts among young children are not, and their presence is a signal that something may be wrong. The same body of research reminds us that not all such contact is voluntary. Some adults recalled being coerced into sexual activity by another child through trickery, bribes, threats, or force. It's important for parents to recognize what forms of sex play are developmentally normal and healthy, and what forms may be a sign of abuse.

In the cognitive dimension, children this age start to grasp the meaning of sex as an actual act — typically understanding it as when a penis enters a vagina. Children also begin to develop love mapsi, which is a cognitive understanding of what a romantic and sexual relationship should look and feel like (Money, 1986). They may come to understand sex as something that "married people do," or that "men get women flowers when they're in love." This is a great opportunity for caregivers to teach children about sex and relationships. Information tends to stick best when it is tied to a real, relevant moment — while getting dressed, while looking at art, while watching a couple on TV. Explanation of sex and "where babies come from" can grow more detailed with age. For a four-year-old, the explanation may just be that "a baby grows in a special place inside the mother." By the age of 6–8, it's perfectly fine to explain sex fully. In fact, knowing what sex actually is can help protect children from being sexually mistreated by others (Astle et al., 2023; Kim et al., 2023).

Two children role-playing a wedding or married couple during pretend play. — **Figure 10.8.** As children build "love maps," they rehearse adult romantic roles — playing house, getting "married," and imitating the relationships they see around them.

In the social dimension, children become "other-incorporative," folding other people into their emotional world. Through daily interactions with caregivers, they form attachments that tend to feel secure, anxious, or avoidant — patterns that, as we will see shortly, affect later adult relationships.

The gender dimension takes a big leap in early childhood. As young as 2 or 3, children begin asserting a gender label: "I'm a boy," "I'm a girl." They start absorbing gender roles from family, culture, and the wider world, and for a while gender identity often becomes quite rigid, rehearsed through fierce opinions about which toys and activities belong to which group. Even by age two-and-a-half, girls in Western societies show a preference for pink clothes and toys, while boys actively avoid the color (Lobue & DeLoache, 2011). Ironically, pink used to be seen as a masculine color. In a popular fashion journal of the 1800s, the authors wrote, "The generally accepted rule is pink for the boys, and blue for the girls. The reason is that pink, being a more decided and stronger color, is more suitable for the boy, while blue, which is more delicate and dainty, is prettier for the girl" (cited in Grannan, 2021). Clearly, these "gender rules" are not set by biology but are simply cultural ideas that children absorb.

Around the ages of 4–5, children develop the idea of gender constancyi — that a person's gender is stable over time and not changed by surface features like a haircut or a costume (Kohlberg, 1966). A very young child may think a girl becomes a boy if she puts on "boy" clothes, but an older child knows that clothes don't determine a person's gender.

Screenshot from the Gender Constancy video. Click to watch it on YouTube. — **Video 10.1.** Gender constancy in action: young children gradually come to understand that a person's gender stays the same even when surface features like hair or clothing change. Watch on YouTube ↗

This is also a period in which a child's trans identity may become more visible. Many trans adults recall that, as children, they began developing an idea that they were "born into the wrong body," or that they preferred the toys, clothes, and names of the other gender. Findings from a large, ongoing research project by Kristina Olson find that many (although not all) transgender adults report that, as children, they were more accepting of gender nonconformity, such as wearing opposite-sex clothing or wishing to be addressed using opposite-sex pronouns (Olson et al., 2015). Her research shows that trans children who are supported by their families and communities during this time show no elevated risk of depression or anxiety, compared to gender-conforming children (Olson et al., 2016). While rates of mental illness are 3–6 times higher in the trans community than in the general population, Olson's research shows that most (if not all) of this is due to having their identities rejected, rather than supported (Wanta et al., 2019).

A gender-nonconforming child expressing their identity through dress and play. — **Figure 10.9.** Research by Kristina Olson finds that transgender children who are supported by their families show no elevated rates of anxiety or depression compared with their cisgender peers.

In the orientation dimension, most children this age gravitate toward strong same-gender friendships. The age at which a person first becomes aware of their sexual orientation varies widely. Some gay and lesbian adults recall strong same-gender attractions in early childhood, while others become aware only much later. And in the erotic dimension, the body map grows more detailed as children discover what body areas and behaviors feel good. Here again, a caregiver's response matters: warm acceptance tends to predict healthier adult sexuality, while shame and punishment tend to predict later problems (Yang et al., 2024).

Fun Fact: A Doll With No Assigned Gender. In 2019, the toymaker Mattel released a line of dolls called Creatable World, designed with no fixed gender in mind. Each doll could be styled with long or short hair and dressed in skirts, pants, or both, so a child could make the doll whoever they wanted. The launch reflected a broader cultural loosening of the rigid toy-aisle gender rules that children start policing so fiercely around age three. Unfortunately, the toy was a commercial flop, with only 5% of adult shoppers interested in the doll. This was likely driven, in part, by a conservative backlash against the dolls, with One Million Moms and other conservative groups petitioning against the dolls' release (Gilchrist, 2019). Clearly, many adults aren't ready to embrace gender inclusiveness for their children.

Mattel's Creatable World gender-inclusive doll, which can be styled with different hair and clothing. — **Figure 10.10.** Mattel's gender-inclusive Creatable World dolls (2019) could be styled as any gender, reflecting — and testing — a cultural loosening of toy-aisle gender rules.

Multiple Choice

A preschool teacher finds two four-year-olds who have taken off their shirts and are curiously looking at each other's bodies while "playing doctor." Based on the research, the most accurate interpretation is that this behavior is:

AA warning sign of sexual abuse that should be reported immediately

BEvidence that the children have been exposed to pornography

CA common, curiosity-driven form of sex play typical for this age

DA sign of unusually advanced sexual development

Preadolescence (Ages 8 to 12)

Preadolescence is the runway to puberty. During these years, children experience a slow chain of hormonal events that will eventually launch puberty. This brings a modest uptick in sexual interest and behavior. Masturbation may take on a more deliberate, adult-like form. The age at which boys begin intentionally masturbating is closely tied to when they enter puberty, while for girls the onset is much more spread out and less clearly linked to physical development. Some preadolescents begin to dabble in coupled activities like dating and kissing. Kids this age may develop "crushes" on boys and girls they like. Socially, we call these types of feelings "other-incorporative," as they involve sexual feelings toward others.

Fun Fact: The Surprising History of "Spin the Bottle." The earliest version of "spin the bottle" didn't involve kissing at all. Bottle-spinning parlor games first emerged in the 1920s, which featured a "Bottle of Fortune" that would be used to select prizes at carnivals (Stanton, 2007). The version we recognize today — where the bottle determines who will be kissed — is an American invention that cropped up after WWII, between 1945 and 1950. Kissing games, like "spin the bottle" and "seven minutes in heaven," have their roots in much earlier games played by Victorian children. In one such game, called "post office," girls and boys would gather in two different rooms. Then a teen from one room would invite someone of the opposite gender to the "post office" (a separate, private room) to give them a letter (a kiss). The person who received the letter would then select another person to give it to, and so on (Hill, 2014).

A group of teenagers playing spin the bottle at a party in the 1960s. — **Figure 10.11.** Kissing games like "spin the bottle" trace back to Victorian-era parlor games and remain a rite of passage into the social world of adolescence.

Cognitively, a new sexual self-consciousnessi sets in, and with it a deliberate hunt for information about sex. Abstract jokes, teasing, and curiosity about explicit images often begin here. These are often early attempts to understand sexuality, as well as make light of a subject that may seem strange and even a bit scary. A popular schoolyard joke is, "Why isn't there a pregnant Barbie doll? ...Because Ken came in another box!" Hidden in the taboo punchline is a tacit understanding of sex, pregnancy, and female anatomy. "Getting the joke" is like a rite of passage for many preteens; a demonstration that they "know the secrets" of the adult world.

In the gender dimension, preteens often impose gender segregation on themselves, and gender roles grow more rigid. Most kids this age insist on expressing their gender through stereotypically masculine or feminine clothing and accessories, and they grow markedly less tolerant of peers who break gender rules. Gender-nonconforming boys tend to have the hardest time, often facing social rejection and even physical attacks (Toomey et al., 2010). While girls are sometimes singled out for "boyish" behavior, some traditionally masculine traits, such as being assertive and athletic, are often praised in girls too (van Beusekom et al., 2020).

A group of boys playing together, separated from a group of girls. — **Figure 10.12.** In preadolescence, children often segregate themselves by gender and police gender rules more strictly than at any earlier age.

In the orientation dimension, this is the age when many kids begin to develop "feelings" toward others of the same or opposite gender. Same-sex attraction is common among boys and girls, perhaps because of broader gender segregation during these years (Li & Hines, 2016). Early childhood crushes don't necessarily dictate adult sexual orientation, but it is a time when many LGBT+ people report experiencing a "sexual awakening." Although the process of "coming out" — which involves self-identifying as LGBT+ — typically doesn't happen until children are teenagers or young adults (Beard et al., 2015).

During this time, love maps grow richer and more complex, as preteens build up more detailed expectations about sex and romantic relationships. The erotic dimension displays an emerging sense of oneself as a sexual being, colored strongly by whether the child has internalized messages about what types of sexual expression are acceptable and whether sexuality itself is good or bad.

Multiple Choice

A sixth-grade teacher notices that her 11-year-old students have suddenly started sorting themselves strictly by gender at lunch, and several boys openly mock a classmate who joins the girls to jump rope. According to the chapter, this spike in rigid gender policing during preadolescence is best understood as:

AA sign that these particular children will grow into intolerant adults

BA normal, temporary peak in gender-role rigidity common at this age

CProof that the school has failed to teach acceptance

DAn early symptom of a behavioral disorder

10.3 Attachment: A First Blueprint for Love

Of all the things that happen in the first years of life, few matter more than attachmenti — the deep emotional bond that forms between a child and their caregivers (Bowlby, 1969). This bond begins in the hours after birth and continues to develop throughout childhood. Attachment is built out of thousands of ordinary moments: being held, fed, soothed, and touched. These are a person's first experiences of love. And the quality of these first bonds — whether they are steady and secure or unstable and frustrating — can shape a person's capacity for emotional and sexual closeness for the rest of their life. Attachment is where the emotional groundwork of future relationships is established.

Styles of Attachment

Attachment stylesi are patterns in how infants relate to their caregivers, which tend to persist and influence adult relationships (Ainsworth et al., 1978). The idea grows out of John Bowlby's theory that human infants are biologically prepared to form a bond with a primary caregiver, a bond that serves the evolutionary function of keeping a vulnerable child close to protection (Bowlby, 1969). There are three established childhood attachment styles, which are based on how well children can utilize their caregivers as sources of comfort and security.

Children with secure attachmenti use the caregiver as a safe base. They happily and boldly explore new environments when caregivers are present. They are often confident and easy-going, even around strangers. But if a caregiver leaves the child alone, they will become quickly disoriented and upset. However, the child is also quickly soothed once the caregiver returns. This underlies a simple understanding that the caregiver is a reliable source of protection and comfort, which can be used when needed. Across studies in eight countries, roughly two-thirds of infants are classified as secure (van IJzendoorn & Kroonenberg, 1988). They tend to have parents who are consistently available and emotionally supportive (De Wolff & van IJzendoorn, 1997).

A warm, responsive parent holding and comforting a happy baby. — **Figure 10.13.** Secure attachment grows out of warm, consistently responsive caregiving. The child learns to use the caregiver as a safe base from which to explore the world.

Children with anxious attachmenti, sometimes called resistant attachment, are frequently nervous and clingy. They may be too upset to explore even attractive spaces, such as rooms with toys and other children. If a caregiver leaves an anxious infant alone, they quickly become panicked and cannot be easily soothed, even when the caregiver returns. This pattern belies uncertainty about whether a caregiver will be there to soothe and protect when they're needed (Cassidy & Berlin, 1994). About 15% of infants and young children show this attachment style (van IJzendoorn & Kroonenberg, 1988). While not always the case, many such children have parents who are loving but sometimes unavailable. This can be due to a parent who is extremely busy, such as those who work multiple jobs, are raising many children, or are caregivers for their own parents.

A distressed, clingy child holding tightly to a caregiver. — **Figure 10.14.** Children with anxious attachment are often nervous and clingy — too distressed to explore even inviting spaces, and hard to soothe when a caregiver returns.

Children with avoidant attachmenti appear, on the surface, unbothered. They explore without much reference to the caregiver, show little distress at separation, and pointedly ignore or avoid the caregiver when they return. This apparent coolness is not the same as security. Physiological measures suggest these children are stressed, but they have learned to mask it (Spangler & Grossmann, 1993). This is often because their bids for comfort (e.g., crying) have been punished in the past. About 20% of infants and young children show this pattern (van IJzendoorn & Kroonenberg, 1988).

A child turned away from a caregiver, appearing indifferent to their presence. — **Figure 10.15.** Children with avoidant attachment appear indifferent to separation and reunion, but physiological measures reveal they are stressed and have simply learned to mask it.

It's important to note that not every child can be described as consistently secure, anxious, or avoidant. Some infants behave in ways that fit none of the categories, producing odd, contradictory, or fearful reactions to their caregivers. When faced with their parents, they may freeze in place, approach while looking away, or show a mix of happy and angry or sad emotions. Main and Solomon (1990) proposed a fourth classification, called disorganized attachment, to describe these children whose behavior suggests the breakdown of any coherent strategy for managing distress. The pattern is thought to arise when the caregiver is at once the source of comfort and the source of fear, leaving the child with no workable solution. Disorganized attachment is often tied with childhood abuse, neglect, or frightening parental behavior (Main & Hesse, 1990; van IJzendoorn et al., 1999). In low-risk community samples, roughly 15% of infants are classified as disorganized, but that figure climbs steeply in high-risk and mistreated samples (van IJzendoorn et al., 1999).

The reason attachment belongs in a chapter on sexual development is that these early patterns do not stay in the nursery. A large body of research finds that childhood attachment styles tend to resemble patterns of romantic attachment when those children grow up (Hazan & Shaver, 1987). Adults who were securely attached as children more often find it easy to trust partners and to balance closeness with independence. Adults with anxious histories more often crave closeness while fearing abandonment. Adults with avoidant histories more often keep partners at arm's length. Secure attachment in childhood has been linked to a range of good outcomes later on, such as stronger friendships and more satisfying romantic relationships (Ainsworth et al., 1978). We'll be revisiting adult attachment styles in a later chapter.

It is also worth noting that attachment patterns are not identical across the world. Cultures differ in how they raise infants — how much they encourage independence, how physically close parents and babies stay, how quickly a crying baby is soothed — and these differences show up in how attachment behaviors are distributed and expressed from one society to the next (Ainsworth et al., 1978). What looks "avoidant" in one culture's parenting norms may reflect a value placed on early independence. Although, one core insight holds across cultures: warm, responsive caregiving builds the secure foundation on which later love is more easily built.

Fun Fact: Attachment Looks Different Across Cultures. If you apply Ainsworth's attachment styles to other cultures, you can get some weird findings. In northern Germany, roughly half of the infants appear to be avoidant, not reacting to being separated from their parents and barely acknowledging them when they return (Grossmann et al., 1985). In Japan, almost all babies appear highly anxious, showing strikingly strong reactions to being separated from their mothers (Takahashi, 1986). How can infants who are far too young to know anything about their own culture develop so differently? It turns out German parents prize early independence — often leaving their babies alone for long stretches at a time — while Japanese parents are rarely apart from their babies, even for a second. It also turns out that neither of these parenting styles is better or worse than the other, with most children in both countries developing normally both emotionally and romantically (van IJzendoorn & Kroonenberg, 1988). When conducting research, it's important to be aware of the Western biases we bring into our theories and methods, and to not judge other cultures until they're studied on their own terms.

A Japanese mother holding her baby closely. — **Figure 10.16.** Cultural context shapes attachment behavior. Japanese infants, rarely apart from their mothers, tend to react strongly to separation — a pattern that can look "anxious" only through a Western lens.

Multiple Choice

In a laboratory study, a one-year-old barely reacts when her mother leaves the room and then pointedly ignores her when she returns, turning back to the toys. Yet physiological measures show the child's stress levels are elevated the whole time. This pattern best fits which attachment style?

ASecure attachment

BAnxious (resistant) attachment

CAvoidant attachment

DDisorganized attachment

10.4 Learning About Sex: Parents, "The Talk," and Sex Education

Children are going to learn about sex one way or another. If left to educate themselves, children often turn to friends, mass media, and the Internet. These are often low-quality sources of information, where kids are likely to receive rampant misinformation about sex (Buhi et al., 2010). The worst teacher of all, as we will see later in the chapter, may be pornography.

Children whispering and sharing information about sex among themselves. — **Figure 10.17.** Left to educate themselves, children often turn to friends, media, and the Internet — frequently low-quality sources rife with misinformation about sex.

Parents & "The Talk"

Around 75% of parents report having talked to their children about sex. But most parents just teach their children how to say "no." Fewer than half report ever discussing safe sex — such as how to use condoms or other forms of birth control. Not talking about sex is a kind of communication in itself, sending the message that the topic is shameful. Children raised in that silence more often grow into adults who struggle to talk with their own partners and children about sex.

A parent having an open, age-appropriate conversation about sex with their child. — **Figure 10.18.** "The talk" works best not as a single dreaded conversation but as an ongoing dialogue that starts early and grows more detailed as a child matures.

The single most useful thing to understand about "the talk" is that it shouldn't be a one-time event. A single, dreaded conversation somewhere around fifth grade or one awkward "birds and bees" speech does not work well. Like teaching reading, sex education should start when children are small and grow in complexity as they grow up. Experts suggest matching the content to a child's age and stage. An evidence-informed roadmap looks like this:

Ages 1 to 3: Teach the real names for body parts — penis, testicles, vulva, vagina. Children who know the real words for their body parts are better able to describe what has happened to them, which is one reason this simple practice is considered a small but real protection against abuse. It's also important to not discourage or punish self-exploration. Instead, frame it as something for "private" spaces rather than as something bad.
Ages 4 to 5: Begin to explain, simply, how a baby grows inside a woman's uterus.
Ages 6 to 8: Talk about the changes that puberty will bring and explain the basics of how sex works.
Ages 9 to 11: Discuss masturbation openly as normal and healthy, talk plainly about intercourse and foreplay, and explain how to prevent pregnancy and sexually transmitted infections.
Ages 12 and up: Ensure access to accurate information about contraceptives, as well as how to access them. This might seem too early to give kids access to condoms, but national surveys find that about 11% of children have had penetrative sex by the time they're 14 years old (Cavazos-Rehg et al., 2009).
At every age: Answer the questions children actually ask, when they ask them, and talk honestly about how sex is portrayed by media, the Internet, and among their peers.

Multiple Choice

A parent asks their pediatrician why she recommends teaching a toddler the words "penis" and "vulva" instead of cute family nicknames. The best evidence-based answer is that children who know accurate anatomical terms:

ATend to become sexually active at an earlier age

BAre better able to clearly describe abuse, which offers some protection

CUsually become confused by clinical-sounding language

DLose their natural sense of privacy and modesty

Two Kinds of Sex Education

At the level of schools and policy, sex-education programs come in two broad types. Abstinence-only educationi teaches that not having sex until marriage is the only acceptable choice and typically avoids or downplays information about contraception. Comprehensive sex educationi also treats abstinence as a valid and respected choice, but also gives students accurate information about contraception, sexually transmitted infections, consent, and what healthy sexual relationships look like.

The evidence strongly favors the comprehensive approach. Abstinence-only programs, including popular virginity-pledge campaigns, have repeatedly been shown to have essentially no effect on whether or when teens have sex (Kohler et al., 2008). What they do accomplish is leaving teens less prepared when they do become sexually active, which can raise the risk of unintended pregnancy and infection.

Comprehensive programs make teens considerably more likely to protect themselves when they become active. Contrary to some parents' fears, talking to kids and teens honestly about sex does not make them more likely to have sex. It simply provides them with helpful information they can use when they do become sexually active. Analyzing a national sample, researchers found that teens who received comprehensive sex education had significantly lower odds of teen pregnancy than those who received abstinence-only instruction or none at all (Kohler et al., 2008). Despite this, the reach of school-based sex education has been shrinking, with fewer and fewer schools offering it at all (Lindberg et al., 2016). It is also worth noting that, contrary to the impression left by the occasional loud controversy, the large majority of adults actually support broad-based sex education in schools (Pickering, 2025).

Students in a classroom receiving comprehensive sex education. — **Figure 10.19.** Comprehensive sex education treats abstinence as one valid choice while also teaching about contraception, STIs, and consent — and research finds it more effective than abstinence-only approaches.

Fun Fact: The Dutch Approach. The Netherlands is often held up as a model for how sex education can work better than in the U.S. (Rough, 2018). Dutch children begin learning age-appropriate lessons about bodies, feelings, and relationships in early primary school, such as learning about bodily autonomy by age 4 and about penetrative sex by age 9. The culture treats teen sexuality as a normal thing to be guided through, rather than a danger to be denied. The results are striking: the Netherlands has among the lowest rates of teen pregnancy in the world, and Dutch teens tend to report that their first sexual experiences were wanted and well-timed rather than regretted (Rutgers International, 2023).

Age-appropriate Dutch sex-education books for young children. — **Figure 10.20.** Dutch children begin age-appropriate lessons about bodies and relationships in early primary school. The Netherlands has among the lowest teen pregnancy rates in the world.

Multiple Choice

A parent asks a pediatrician when they should start "the talk" with their child. Based on current evidence, the best advice is:

AWait until the child is about to enter puberty, then cover everything at once

BBegin early with simple, age-appropriate information and build on it over the years

CLeave sex education entirely to the child's school

DAvoid the topic unless the child asks a direct question

10.5 Sexuality in Adolescence

Adolescence is where sexuality steps into full view. During puberty, the body changes dramatically, and a surge of sex hormones — especially testosterone — drives a sharp rise in sexual interest and behavior in most young teens. Alongside these physical changes, teenagers wrestle with a set of big questions pertaining to their sexual identity: What is my gender, and how do I want to express it? Who am I attracted to? How attractive am I? What kind of relationships do I want? Because teens can now think abstractly, they can also understand that the answers need not be simple or binary, and most are at least somewhat aware of a range of LGBT+ identities.

Two teenagers in an early romantic relationship. — **Figure 10.21.** In adolescence, sexuality steps into full view as teens navigate big questions about identity, attraction, and the kind of relationships they want.

Public worry about teen sexuality often runs ahead of the facts, so some numbers are worth stating up front. According to data from the Centers for Disease Control and Prevention, around 42% of never-married female teens and 38% of never-married male teens ages 15 to 19 have had sexual intercourse (CDC, 2017). That is actually a notable decline from earlier decades, which is part of a steady downward trend since the late 1980s. And when teens do have sex, most are cautious about it. The CDC reports that roughly 80% of females and 90% of males who had intercourse before age 20 used contraception the first time (CDC, 2017). In other words, teens tend to have sex at later ages than people often expect — usually around ages 17–19 — and are often more responsible than parents give them credit for.

The first time someone has sex is known as sexual debut, and scientists have long studied why some teens "debut" earlier than others. A good deal of it comes down to simple biology. For decades, scientists have found that teens who have higher levels of testosterone tend to have sex at earlier ages, and this goes for girls as well as boys (Udry, 1988; Udry et al., 1985; Halpern et al., 1993, 1997, 1998). In one study of 10th graders (roughly 16 years old), among teens who were in the lowest quarter of testosterone production, only 12% had experienced sexual intercourse. Among those in the highest quarter, nearly 70% had. If you knew nothing else about a teen other than their testosterone levels, you would have a pretty good chance of predicting when they have sex.

Beyond biology, some social factors also matter. Teens who are less affluent, less religious, and less educated tend to have sex earlier, largely because of the norms of the communities around them. In communities with high unemployment or few prospects, there is simply less incentive to delay sex, because there is less sense that waiting will pay off in a better future.

Teen girls and boys are also affected by different factors. Drawing on a large Canadian survey, researchers found that sexual debut for girls was linked to earlier puberty (especially precocious puberty), lower self-esteem, being overweight, and having already tried smoking or drinking (Garriguet, 2005). Meanwhile, for boys it was linked to poor family relationships and having tried smoking. One consistent theme is that where sex is not discussed and information is scarce, sexual debut tends to come earlier, not later.

One finding that surprises many people is that a parent's attitudes about sex have no impact on when their teen children start having sex. Whether a parent is perfectly fine with their teen daughter or son having sex, or absolutely forbids it, makes no difference. What parental communication does affect is safety: when parents actually educate their children about safer sex, those teens are more likely to protect themselves once they become active. In other words, parents cannot reliably push the start date back, but they can strongly influence whether their child is prepared.

Multiple Choice

A father is convinced that if he strictly forbids his teenage son from having sex, his son will start later than he otherwise would. Based on the research described in the chapter, what should we most likely expect?

AThe son will almost certainly delay sex because of the rule

BThe father's attitude will have little effect on when his son has sex, though talking openly could shape how safely he does

CThe strict rule will push the son to have sex much earlier out of rebellion

DThe rule will work only if the father repeats it often enough

Peers, Pop Culture, and the "Super Peer"

Puberty supplies the drive, but social forces shape how that drive is understood and expressed. In adolescence, peers become powerful referees of what is normal. Beyond the immediate friend group, mass media and social media act as a kind of amplified peer. Super-peer theoryi holds that the characters, celebrities, and influencers teens watch can set the perceived norms for behavior — around alcohol, drugs, and sex (Elmore et al., 2017). When glamorous, hyper-sexualized stars model a particular version of desirability, many teens absorb the message that they must look and perform a certain way to be worthy. Between fitness gurus and looks-maxxers, teens today often feel a lot of pressure to measure up to these unrealistic standards (Moreno et al., 2009).

A social-media influencer filming content that models an idealized lifestyle for teen viewers. — **Figure 10.22.** Super-peer theory holds that celebrities and influencers can set teens' perceived norms for sex, alcohol, and appearance — often modeling unrealistic standards.

The phone has also introduced sextingi — the sending, receiving, or forwarding of sexually explicit messages, photos, or videos through a digital device (O'Keeffe & Clarke-Pearson, 2011). By one meta-analysis, roughly 15% of teens have sent a sext of themselves and about 25% have received one (Madigan et al., 2018). Sexting carries real risks — images can be shared far beyond the intended recipient, and in some cases minors have faced legal consequences — which makes it an important topic for honest conversation rather than panic.

Learning from Pornography

Perhaps the most consequential media shift in recent years is the advent of free and easily available pornography. In a demographically representative national survey of United States teens, the average age of first exposure was 12, with about 15% having seen online pornography by age 10 (Robb & Mann, 2023). By age 17, 73% of teen girls and boys report having seen hardcore pornography.

An illustration of a young person watching pornography on a screen. — **Figure 10.23.** For many teens, freely available pornography has become an unintended and misleading sex educator. The average age of first exposure is about 12.

The concern is not moral so much as educational: pornography is a poor sex-ed teacher, but a large share of young people treat it as one anyway. In qualitative interviews, low-income Black and Hispanic youth described pornography as a primary source of information about how sex is done, using it to fill the gaps left by adults and schools (Rothman et al., 2015). Indeed, studies show that teens who receive abstinence-only sex education are more likely to watch porn, perhaps as a way to better educate themselves about sex (Fraumeni-McBride & Willoughby, 2024; Nie, 2021). In nationally representative samples, 1 in 5 teens say that pornography reflects "real world sex," and many more report learning about sex from porn (Kuan et al., 2022).

The trouble lies in what the medium teaches. Content analyses find that mainstream pornography offers an unrealistic picture of what bodies look like, how long sex lasts, and how arousal and pleasure actually work. Content analyses show that nearly 90% of porn videos portray extremely aggressive sex acts, such as slapping, choking, and rough sex, which is mostly directed at women (Bridges et al., 2010; Fritz et al., 2020). Beyond what is depicted is what is not shown in pornography. Porn almost never features the use of contraceptives or affirmative consent. Teens who watch porn regularly seem to take note. They tend to hold more gender-stereotyped beliefs about sex (e.g., men should be sexually aggressive and women should be sexually receptive), less confidence about their bodies and sexual performance, and greater acceptance of sexual aggression (Peter & Valkenburg, 2016).

At this point, it's hard to know what long-term effects pornography has on child development. It's just too early to tell. Interestingly, while only 30% of teens think porn has affected them personally, 70% reported that they knew someone who was negatively affected by it. Studies have already found that boys and young men who regularly watch porn are more likely to be physically aggressive during sex and are more likely to pressure partners in the bedroom (Rothman et al., 2021). One clear example is choking during sex. What was once extremely rare, choking has become common among teens and young adults (Herbenick et al., 2020). In one sample of urban youth, 44% had been asked by a partner to do something sexual the partner had seen in pornography (Rothman & Adhia, 2016). This was most often a girl who was asked to do rough sex, and the vast majority reported not enjoying or wanting to do the activity.

Sex educators are just starting to catch up, with growing efforts aimed at educating young people about porn specifically. This approach has been termed pornography literacy (Rothman et al., 2018). It involves teaching teens to treat porn as scripted entertainment, rather than as a documentary record of how sex happens in the real world. A good porn-literacy lesson makes a few things explicit:

The bodies on screen are curated and often surgically or digitally altered.
The stamina and choreography shown on screen are performances rather than what normally occurs in the bedroom.
While most porn depicts sex that is aggressive or even violent, most people report disliking that type of sex.

Early evaluations of such programs are encouraging. A pilot of a five-session curriculum called The Truth About Pornography was shown to shift attitudes about porn in the intended direction (Rothman et al., 2018). Having gone through the program, teens were less likely to view porn as realistic or as a good way to learn about sex. Another study found that porn literacy programs can help weaken the link between viewing porn and objectifying women (Vandenbosch & van Oosten, 2017). The most honest message to a teenager is not that pornography is evil, but that it is fiction: a genre with its own conventions, made to arouse and to sell. It is a poor source to learn what real bodies look like, how long sex lasts, or what a partner actually wants.

Multiple Choice

A 16-year-old tells a counselor that he learned "how sex is supposed to go" mostly from pornography and now feels anxious that his body and experiences do not measure up. The counselor recognizes this as a common result of which issue?

AA hormone imbalance caused by puberty

BPornography functioning as an unrealistic and misleading source of sex education

CNormal, healthy sexual development with no cause for concern

DEvidence that the teen is being sexually abused

Teen Pregnancy

One great development over the last few decades is the continually falling rate of unplanned teen pregnancies. Each year, a little over 1% of U.S. teen girls give birth, a rate that has dropped sharply since its peak in 1991 (CDC, 2024). The main engine of that decline is straightforward: teens are simply having less sex than they used to, and those who are sexually active are using contraception more consistently.

A line graph showing U.S. teen birth rates declining sharply since their 1991 peak. — **Figure 10.24.** U.S. teen birth rates have fallen sharply since their 1991 peak, driven largely by teens having less sex and using contraception more consistently (CDC, 2024).

Even so, the U.S. still has one of the highest teen pregnancy rates among wealthy Western nations (CDC, 2024). Within the country, the highest rates cluster in Southern states — the same states that most often rely on abstinence-only education and where teens have less access to contraception.

The stakes are high because early parenthood is hard on everyone involved. Teen pregnancies carry large costs, both personal and public (Kearney & Levine, 2012). The children of teen mothers face elevated risks across a range of outcomes, from poorer health to higher high-school dropout rates (Kearney & Levine, 2012). Teen mothers themselves are less likely than their peers to obtain a college education and often face economic hardship. None of this is about blaming young parents. It is about recognizing that the "easy solution" so often proposed — simply telling teens to abstain — is exactly the approach that leads to more teen pregnancies.

Fun Fact: Lower Teen Birth Rates Are Due to Three Factors. Scientists have been tracking dropping rates of unplanned teen births for over three decades now, and they think they've homed in on the main factors driving it (Lei & South, 2020; South & Lei, 2021). Across the board, teen girls and boys are having less sex than they used to. This is largely because they're less likely to be engaged in romantic relationships at younger ages compared to past generations. Teen girls are also much less likely to binge drink than teen girls of the past. This is believed to account for about 20–30% of the drop in unplanned pregnancies, as binge drinking is often related with risky sex. One factor driving boys to have less sex is perhaps more surprising. Evidence suggests that increases in playing video games is directly related with having less sex among this cohort. Between fewer keggers and more nights playing online games on Discord, modern teens have found safer ways to have fun!

Multiple Choice

A health teacher wants to lower teen pregnancy rates in her district. Based on the research, which approach is most likely to succeed?

AAn abstinence-only program that asks students to sign a virginity pledge

BA comprehensive program covering both abstinence and how to use and obtain contraception

CRemoving sex education entirely to avoid encouraging sexual activity

DRelying on students to learn about sex from the Internet

Study Guide

After reading Chapter 10, you should be able to answer each of the questions below. Use your own words where possible, and support your answers with examples or evidence from the text.

10.1 The Many Dimensions of Sexual Development

Explain why the text argues that sexuality "begins before birth." What evidence supports the idea that even infants are capable of sexual response, and why does this not mean that infants experience sexual desire the way adults do?
Name and briefly describe the five dimensions of sexual development. Choose one dimension and trace how it might change from infancy to preadolescence.
Why is research on childhood sexuality so limited? Describe at least two specific obstacles that make this area harder to study than other topics in human sexuality.

10.2 From Infancy Through Preadolescence

What is the "conspiracy of silence," and where did the modern ideal of childhood sexual innocence come from? What does research suggest about whether children are harmed by seeing ordinary nudity or by learning that their parents are sexual beings?
What is comfort contact, and why does it matter for later development? Describe what is typical in the erotic and social dimensions during infancy.
What is sex play, and roughly how common is it? Explain how caregivers should ideally respond when they encounter it, and why overreacting can be counterproductive.
What is gender constancy, and how does a child's understanding of gender change across early childhood and into preadolescence? Why might gender-nonconforming boys have a harder social time than gender-nonconforming girls?
Summarize what research by Kristina Olson and colleagues has found about transgender children. In what ways are they similar to their cisgender peers, and what does the research suggest about the sources of anxiety and depression in this group?

10.3 Attachment: A First Blueprint for Love

What is attachment, and how does it form in infancy? Explain the reasoning behind the claim that these early bonds shape a person's capacity for love and sexual closeness in adulthood.
Describe the Strange Situation procedure. Why are the reunion moments considered more revealing than the separations?
Compare secure, anxious, and avoidant attachment styles. For each, describe how a child typically behaves during the Strange Situation and what underlying expectation about the caregiver the pattern reflects.

10.4 Learning About Sex: Parents, "The Talk," and Sex Education

The text argues that "the talk" should not be a single conversation. Explain this claim and describe how the content of sex education should change as a child grows from a toddler to a teenager.
Why does the text say that using correct anatomical names for body parts is about more than reducing awkwardness? Connect this practice to abuse prevention.
Compare abstinence-only and comprehensive sex education. What does the research say about the effects of each on the timing of teen sex, on teen pregnancy, and on protective behavior? Use this evidence to respond to someone who claims comprehensive sex education "just encourages teens to have more sex."

10.5 Sexuality in Adolescence

Public perception often holds that teen sexual activity and teen pregnancy are rising. What do the actual data show, and what are the main reasons behind these trends?
Explain super-peer theory and the idea of the "media super-peer." How can social media lead teens to misjudge what their peers are actually doing, and why does that matter?
Why does the text describe pornography as a poor teacher of sex? Identify at least three specific misconceptions that teens may absorb from learning about sex through pornography.
The chapter reports that a parent's attitudes about sex have little effect on when their teen becomes sexually active, but that parental communication still matters. Resolve this apparent contradiction: what exactly can parents influence, and what can they not?

Key Terms

Abstinence-only education: A type of sex education that teaches not having sex until marriage as the only acceptable choice and generally avoids information about contraception. Research finds it does not delay when teens have sex and leaves them less prepared when they do.
Anxious attachment: An insecure attachment style in which a child is clingy and easily distressed, and at reunion seeks comfort while also resisting it. It reflects uncertainty about whether the caregiver can be relied on. Also called insecure or resistant attachment.
Asexual: Having little or no sexual attraction to others. The chapter uses the term to correct the mistaken idea that children are entirely without sexual feeling or response.
Attachment: The deep emotional bond that forms between an infant and a primary caregiver in the first years of life. Its quality shapes a person's capacity for emotional and sexual closeness in adulthood.
Attachment styles: Consistent patterns in how infants relate to their caregivers, usually grouped as secure, anxious, and avoidant. These early patterns tend to persist and to resemble a person's romantic attachment style as an adult.
Avoidant attachment: An insecure attachment style in which a child appears unbothered by separation and ignores or avoids the caregiver at reunion. The outward calm often masks underlying stress rather than reflecting true security.
Body map: A person's developing internal sense of which parts of the body feel good and which feel bad. It begins to form in infancy and is shaped heavily by how caregivers respond to a child's exploration.
Cognitive dimension: The strand of sexual development involving a child's growing mental understanding of sex, which develops alongside language and a sense of being a separate self.
Comfort contact: The warm physical touch that soothes and reassures an infant. In infancy this need is not yet separated from other needs, and being deprived of it can cause lasting harm.
Comprehensive sex education: A type of sex education that respects abstinence as one valid choice while also providing accurate information about contraception, sexually transmitted infections, consent, healthy relationships, and the diversity of sexuality. Research finds it more effective than abstinence-only approaches at reducing teen pregnancy.
Conspiracy of silence: The unspoken agreement among the adults around a child never to discuss sex openly. It tends to teach children that sex is a shameful topic.
Erotic dimension: The strand of sexual development involving how a person comes to experience and interpret pleasure, including whether they associate it with joy or with guilt.
Gender constancy: The understanding, which develops in steps during childhood, that a person's gender is stable over time and is not changed by surface features like a haircut or clothing.
Gender dimension: The strand of sexual development involving how a person's recognition of gender, their own and others', takes shape and grows more sophisticated with age.
Love maps: A person's developing internal picture of what a romantic and sexual relationship should look and feel like. Love maps begin forming in early childhood and grow richer through preadolescence.
Masturbation: Self-touching of the genitals that produces pleasurable feeling. In infancy and early childhood it is unfocused and experienced as self-soothing, with no adult sexual meaning.
Media super-peer: The idea that social media can act like an amplified peer group, convincing teens that others are engaging in riskier or more frequent sexual behavior than they actually are, which makes those behaviors seem normal and expected.
Orientation dimension: The strand of sexual development involving how a person comes to recognize whom they are attracted to and develops the capacity to form romantic and sexual attachments.
Secure attachment: The healthiest and most common attachment style, in which a child uses the caregiver as a safe base, is distressed by separation, and is quickly comforted at reunion. It reflects trust that the caregiver is reliable.
Sex play: Curiosity-driven behavior, such as "playing doctor," in which young children show or touch one another's genitals. It reflects exploration and imitation of adult roles rather than adult-style sexual interaction, and it is reported by roughly a quarter to a half of parents.
Sexting: The sending, receiving, or forwarding of sexually explicit messages, photos, or videos through a phone or other digital device. Roughly one in four adolescents reports having sent such an image of themselves.
Sexual self-consciousness: A new awareness of oneself as a sexual being that emerges in preadolescence, often accompanied by a deliberate search for information about sex.
Social dimension: The strand of sexual development involving the degree to which a child's experience of sexuality begins to include other people. Also called the interpersonal dimension.
Strange Situation: A laboratory procedure developed by Mary Ainsworth for studying attachment, in which a caregiver and infant go through a series of separations and reunions. The reunion behavior reveals the quality of the underlying bond.
Super-peer theory: The idea that media characters and celebrities can set teens' perceived norms for behavior — around sex, alcohol, and drugs — much as a real peer group would, but with far wider reach.

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