Attachment theory, formulated by British psychiatrist John Bowlby (1907-1990), focuses on the child-parent relationship and the influence of that relationship on subsequent child development (Bowlby 1969/1982, 1973, 1980). Since Bowlby’s original writings were published, attachment theory and research have burgeoned, largely bearing out Bowlby’s tenets about the importance of attachments to human development across the life span.
According to attachment theory, the infant-parent attachment is an evolutionarily adaptive relationship whose principal function is the protection of the child. Bowlby argued that all people are genetically predisposed to form enduring and preferential relationships with principal caregivers because in the earliest environments of human beings such relationships were evolutionarily advantageous.
In addition to his concern with all people’s attachments, Bowlby focused on differences between individuals. At the heart of Bowlby’s thinking about individual differences is the notion of internal working models. Specifically, Bowlby argued that individuals draw on their earliest experiences to create mental maps, or internal working models, to guide their behavior. Internal working models guide people’s expectations, attention, interpretations, and memories. These processes then guide behavior.
According to attachment theory, it is the responses of parents to their infants’ earliest behaviors (crying, looking, reaching) that most heavily influence the development of the infants’ internal working models. Specifically, Bowlby asserted that repeated daily interactions between infant and parent lead the infant to develop expectations about the parent’s caregiving. These expectations are gradually organized into internal working models of the caregiver and of the self in relation to this caregiver. Sensitive, supportive caregiving leads to the development of an internal working model of the caregiver as trustworthy and helpful, and of the self as deserving of supportive care. Insensitive, unsupportive caregiving leads to working models of the caregiver as unavailable and untrustworthy, and of the self as unworthy of supportive care.
With continual use, internal working models come to operate automatically and unconsciously. Over time, individuals are more likely to define their experiences using existing working models than to modify their internal working models to accommodate new, possibly inconsistent information. In particular, people’s working models guide the development of subsequent relationships. This occurs initially by their guiding the individual’s expectations about others’ emotional availability: “the kinds of experiences a person has, especially during childhood, greatly affect … whether he expects later to find a secure personal base, or not” (Bowlby 1979, p. 104). Barring major changes in the environment or the individual, the principal qualities of the infant-parent attachment(s) will be replicated in subsequent close relationships: infants who received sensitive, supportive care will subsequently form supportive, nurturing, close relationships; infants who received insensitive, unsupportive care will form close relationships in which the giving and receiving of care is distorted.
It is important to note that internal working models are not considered to be immutable. As environments and individuals change and develop, working models are likely to require updating; major changes in the environment or in the person require the reformulation of internal working models. Factors such as traumas, losses, and new attachments are those most likely to alter internal working models.
American psychologist Mary Ainsworth (1913-1999) was a lifelong collaborator with Bowlby. Ainsworth’s development of the laboratory Strange Situation procedure galvanized the systematic study of individual differences in infant-parent attachment (Ainsworth et al. 1978). The Strange Situation is a twenty-minute videotaped assessment with a twelve- to twenty-month-old infant, the infant’s parent, and an unfamiliar female “stranger.” There are two brief infant-parent separations during which the infant remains in a laboratory playroom with a selection of toys. Based largely upon the infant’s response to the parent during the two reunion episodes, the Strange Situation classification system distinguishes three main patterns of infant-parent attachment: secure, insecure-avoidant, and insecure-ambivalent.
Approximately 65 percent of infants in most non-pathological samples are classified as secure. During reunion, these infants actively seek to reestablish contact with their parent. Comforted by their parent’s return, secure infants then return to play. In their inclination to seek and receive comfort from their parent and then resume exploration, secure infants are thought to use their parent as a “secure base from which to explore.”
Approximately 20 percent of infants in most non-pathological samples are classified as insecure-avoidant. Infants classified as avoidant are unlikely to cry during the separations. During reunion, these infants actively avoid interaction with the parent and may appear to ignore their parent completely. In their lack of comfort-seeking, avoidant infants appear less able than secure infants to rely on their parent as a secure base.
Approximately 15 percent of infants in most non-pathological samples are classified as insecure-ambivalent. Infants classified as insecure-ambivalent are highly likely to express distress during the separations. During reunion, however, these infants appear to derive little comfort from their parent’s return. These infants demonstrate ambivalence about interacting with the parent that is frequently accompanied by angry, resistant behavior. In their inability to be soothed by their parent, ambivalent infants appear less able than secure infants to rely on their parent as a secure base.
Following Ainsworth’s identification of these three patterns, Mary Main and Judith Solomon (1986) identified a fourth group: insecure-disorganized. Disorganized, disoriented, and frightened reunion behaviors characterize the infants in this group. When an infant is classified as disorganized, the infant is also assigned to the principal attachment pattern (secure, avoidant, or ambivalent) that most strongly coexists with or underlies the infant’s disorganization.
The four patterns of attachment are especially valuable for understanding human development because, as demonstrated by a large body of research, early patterns of attachment consistently forecast later development (Thompson 1999). In brief, children who are classified as secure during infancy later appear more socially competent than children who were classified as insecure. They have more positive interactions with friends and peers; they are also more empathic and less hostile, aggressive, or withdrawn. Infants classified as disorganized are considered most at risk for future emotional and social problems. In addition, consistent with Bowlby’s earliest predictions, these four patterns are also consistently predicted by specific patterns of parenting behavior (Berlin and Cassidy 2000). The disorganized pattern is consistently associated with parental maltreatment (abuse or neglect).
Since the advent of the Strange Situation, numerous other assessments of individual differences in attachment have been developed: the Attachment Q-Sort is an adult-report measure of attachment in infants and young children (Waters et al. 1995). Using modified Strange Situation procedures, researchers have also developed systems for classifying attachment patterns in preschool children (Cassidy and Marvin 1992; Crittenden 1994) and in five- to seven-year-old children (Main and Cassidy 1988). (See Solomon and George  for a discussion of these and other measures.)
After the Strange Situation, the second most widely used assessment of attachment is the Adult Attachment Interview (AAI) (George et al. 1985; Hesse 1999), a one-hour semistructured interview that assesses the adult’s current “state of mind with respect to attachment” (i.e., the current internal working models). During the AAI, adults are asked to discuss early childhood experiences and their influences on adult personality. Although the AAI draws heavily on recollections of early attachment experiences, it is the ways in which the interviewee discusses these experiences that figure most importantly in the individual’s classification into one of four patterns: secure, insecure/dismissing, insecure/preoccupied, or insecure/unresolved. Consistent with the theory, adults’ patterns of attachment reliably predict: (1) the adults’ parenting behaviors, and (2) the quality of their child’s attachment to them. A second arm of adult attachment theory and research uses adults’ self-reports about the way they usually feel and act in romantic relationships to assess “adult attachment style,” both in terms of romantic attachments and more generally (Bartholomew and Horowitz 1991; Hazan and Shaver 1987; Rholes and Simpson 2004).
Since the late 1980s, interventions based on attachment theory and research have proliferated in various settings across the United States and abroad. The field of attachment-based interventions has only just begun to gain order and systemization, especially with respect to the use of theory- and research-based protocol (Berlin et al. 2005). Attachment theory and research are also beginning to be integrated into the diagnosis and treatment of children with reactive attachment disorder, a set of seriously aberrant and problematic attachment behaviors typically associated with parental maltreatment or disruptions in early caregiving relationships Theory- and research-based interventions to enhance early attachments among high-and low-risk parents and children are a promising avenue toward supporting human development on the whole.
SEE ALSO Ainsworth, Mary; Bowlby, John; Parenting Styles; Relationship Satisfaction; Separation Anxiety
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Lisa J. Berlin