By Catherine A. Sanderson, Amherst College
The bond that babies form with the person who is available to respond to their needs and protect them from harm is referred to as the attachment bond. Based on the findings of studies, it has been found that the attachment does not depend on feeding alone; that physical contact is an essential part of developing an attachment bond.

Research Work on Attachment Bonds
Although attachment bonds are beneficial for all babies, research by Mary Ainsworth has shown that the specific attachment bond babies form with their primary caregiver varies and falls into one of three types.
Her findings came out of a standard experimental paradigm she created to examine how infants react to temporary separations from their primary caregivers. This paradigm is known as the strange situation technique.
Strange Situation Technique
This technique follows a situation where a mother comes into a waiting room with her baby, and they spend a few minutes playing with some toys. Then a female stranger enters the room. After a few minutes, the mother leaves the room, so the baby is left alone with the stranger. The mother stays away for a few minutes and then re-enters the room.
This entire period is videotaped so that researchers can examine how the baby responds at two crucial times: what happens when the mom leaves, and what happens when the mom returns.
Types of Bonds
On the basis of studies using the strange situation paradigm, Ainsworth developed a theory that there are three distinct styles or types of mother-infant attachment: secure, anxious, and avoidant.
Secure babies are sad when their mother leaves, but they can be reassured and consoled by the stranger. They are happy to see the mother when she returns, and after greeting her, continue to play with the toys in the room.
Other babies are very upset when their mother leaves and are described as anxious. They aren’t able to be consoled by the stranger (they continue to cry) and after the mother returns, they cling to her and won’t leave her side.
Avoidant babies react in a really different third way. They don’t seem to notice or care when their mother leaves. They also don’t seem to notice or care when their mother returns.
This article comes directly from content in the video series Introduction to Psychology. Watch it now, on Wondrium.
Findings from the Experiment
So, what causes these differences in infant attachment styles? One possibility is that some babies seem more disposed to forming a secure attachment than others; that attachment is a function of nature, not nurture.
These differences may be due in part to differences in babies’ temperaments, which appear even in the first few weeks after birth.

For example, easy babies are cheerful, relaxed, and relatively predictable in terms of sleeping and eating patterns, whereas difficult babies are more irritable, intense, and unpredictable. These early differences in temperament appear to last for quite some time and may be caused in part by differences in heredity: anxious infants have higher heart rates and a more reactive nervous system.
Temperament may also be influenced by the prenatal environment; babies born to mothers who suffered from depression, anxiety, and/or stress during their pregnancy are more likely to show similar reactivity.
Role of Genes in Bonding
Genetics definitely seems to play a role in attachment. Researchers at the University of Iowa found that babies with only long alleles on a gene responsible for serotonin transport are highly likely to develop secure attachment regardless of the parenting they receive. These babies are described as “born secure”, meaning parenting doesn’t seem to matter.
However, babies with one or two short alleles on the same gene develop secure attachments only when their mother engages in responsive parenting but insecure attachments when responsive parenting is absent. This is a gene that’s related to the expression of negative emotion. So, it may be that babies with short alleles are more likely to experience negative emotions.
So, for these babies, good parenting can make a big difference in helping them develop an ability to regulate their greater tendency toward negative emotions. Babies who do get good parenting learn how to manage their negative emotions and can, therefore, form a secure attachment bond with a caregiver.
Babies who do not get good attachment parenting, cannot form a secure attachment or at least have more difficulty managing their emotions and forming other relationships.
Role of Mother’s Temperament
This research also points to how environment, or nurture, influences attachment. Mothers who notice what their babies are doing and respond appropriately tend to have securely attached babies.
On the other hand, mothers who attend to their babies sometimes, but ignore them at other times, tend to have anxiously attached babies. Mothers who largely ignore their babies tend to have avoidantly attached babies.
Effect of Culture on Bond
The role of nurture—the environment—in influencing attachment styles helps explain why the distribution of the attachment styles across countries differs widely. Although the secure attachment is the more prevalent type of attachment style worldwide, the proportion of infants in the two insecure categories differs in different countries.
In countries that tend to place a greater emphasis on independence and self-reliance, such as the United States and many western European countries, relatively more children are classified as avoidant.
In countries that tend to place a greater emphasis on interdependence and social connections, such as Israel and Japan, relatively more children are classified as anxious.
These findings provide further evidence that cultural norms about child-raising, and parents’ behavior, shape the type of attachment style the child develops.
Common Questions about the Types of Attachment Bonds and Their Determining Factors
The bond that babies form with the person who is available to respond to their needs and protect them from harm is referred to as the attachment bond.
Research by Mary Ainsworth has shown that the specific attachment bond babies form with their primary caregiver varies and falls into one of three types. The three types of attachment bonds are secure, anxious, and avoidant.
The type of attachment bond formed is determined by various factors such as the parenting style, genes, nurture, culture, mother’s temperament, and the like.