On This Page:ToggleBackgroundStrange Situation ProcedureScoringResults [Attachment Styles]ConclusionTheoretical EvaluationMethodological Evaluation
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It applies to infants between the age of nine and 18 months.
Background
Much research in psychology has focused on how forms of attachment differ among infants. For example, Schaffer and Emerson (1964) discovered what appeared to be innate differences in sociability in babies; some babies preferred cuddling more than others, from very early on, before much interaction had occurred to cause such differences.
It’s easy to know when you are attached to someone because you know how you feel when you are apart from that person, and, being an adult, you can put your feelings into words and describe how it feels.
However, mostattachment researchinvolves infants and young children, so psychologists have to devise subtle ways of researching attachment styles, usually involving the observational method.
Psychologist Mary Ainsworth devised an assessment technique called the Strange Situation Classification (SSC) to investigate how attachments might vary between children.
Mary Ainsworth’s (1971, 1978) observational study of individual differences in attachment is described below.
Strange Situation Procedure
The security of attachment in one- to two-year-olds was investigated using the strange situation paradigm in order to determine the nature of attachment behaviors and styles of attachment.
Ainsworth and Bell (1971) conducted a controlled observation recording the reactions of a child and mother (caregiver), who were introduced to a strange room with toys. About 100 middle-class American infants and their mothers participated in the strange situation.
The strange situation procedure was designed to be novel enough to elicit exploratory behavior and yet not so strange that it would evoke fear and heighten attachment behavior at the outset.
The child is observed playing for 20 minutes while caregivers and strangers enter and leave the room, recreating the flow of the familiar and unfamiliar presence in most children’s lives.
Ainsworth & Bell observed from the other side of a one-way mirror, so the children did not know they were being observed.
The infant’s behavior was observed during eight pre-determined ‘episodes’ of approximately 3 minutes each.
Scoring
Observers noted the child’s willingness to explore, separation anxiety, stranger anxiety, and reunion behavior.
Two observers narrated continuous accounts into a two-channel tape recorder that also captured a timer’s click every 15 seconds.
This is the standard procedure now, although, for the initial 14 participants, only one observer narrated as the other took notes due to the lack of a two-channel recorder.
For the latter 33 participants, Bell was the sole observer. The observations were later transcribed, consolidated, and coded.
These four classes of behavior were scored for interaction with the mother in episodes 2, 3, 5, and 8, and for interaction with the stranger in episodes 3, 4, and 7.
The criteria include the child’s initiative, persistence, and effectiveness in gaining (or regaining) contact or proximity. The score reflects the intensity and nature of the child’s efforts across different episodes.
They encompass clinging, embracing, resisting release through intensified clinging or turning back and reaching if contact is lost, and vocal protestations.
The behaviors indicative of avoidance include increasing distance, turning away, averting gaze, hiding the face, or ignoring the person, especially when the person is attempting to engage the child’s attention.
Unlike the resistance variable, which is often associated with anger, avoidance may have a neutral tone or reflect apprehension.
It may be seen as a defensive behavior that conceals feelings, possibly including resentment. The coding for this variable distinguishes between the child’s interactions with the mother and a stranger.
These resistant behaviors may alternate with efforts to maintain contact with the person being rejected.
These behaviors indicated the infant’s active search or orientation towards the last seen location of the absent mother (usually the door) or a place associated with her in the unfamiliar setting (her chair).
Strange Situation classifications (i.e., attachment styles) are based primarily on four interaction behaviors directed toward the mother in the two reunion episodes (Ep. 5 & Ep. 8).
The observers noted the behavior displayed during 15-second intervals and scored the behavior for intensity on a scale of 1 to 7.
This allows the observers to tally observations into pre-arranged groupings. It also makes the observations replicable, so the results have greater reliability.
Other behaviors observed included:
Results [Attachment Styles]
Ainsworth (1970) identified three mainattachment styles, secure (type B), insecure avoidant (type A), and insecure ambivalent/resistant (type C). She concluded that these attachment styles resulted from early interactions with the mother.
A fourth attachment style, known asdisorganized, was later identified (Main, & Solomon, 1990).
SecureResistantAvoidantSeparation AnxietyDistressed when mother leavesIntense distress when the mother leavesNo sign of distress when the the mother leavesStranger AnxietyAvoidant of stranger when alone, but friendly when the mother is presentThe infant avoids the stranger – shows fear of the strangerThe infant is okay with the stranger and plays normally when the stranger is presentReunion behaviorPositive and happy when mother returnsThe infant approaches the mother, but resists contact, may even push her awayThe Infant shows little interest when the mother returnsOtherUses the mother as a safe base to explore their environmentThe infant cries more and explores less than the other two typesThe mother and stranger are able to comfort the infant equally well% of infants70%15%15%
B: Secure Attachment
Securely attached childrencomprised most of the sample in Ainsworth’s (1971, 1978) studies.
Infants with this type of attachment explore their environment (explorative behavior) and are moderately distressed when their mother leaves the room (separation anxiety).
Such children feel confident that the attachment figure will be available to meet their needs. They use the attachment figure as a safe base to explore the environment and seek the attachment figure in times of distress (Main, & Cassidy, 1988).
In the context of the Strange Situation, a child displaying secure attachment exhibits the following behaviors:
A: Insecure Avoidant
They show little interest when reunited with the mother (i.e., she returns to the room). Infants are strongly avoidant of the mother and stranger, showing no motivation to interact with either adult. They do not seek contact with the attachment figure when distressed. The stranger is treated similarly to the mother (does not seek contact).
They are very independent of the attachment figure, both physically and emotionally (Behrens, Hesse, & Main, 2007). Insecure avoidant children do not orientate to their attachment figure while investigating the environment.
Such children will likely have insensitive caregivers who ignore their emotional needs (Ainsworth, 1979).
The attachment figure may withdraw from helping during difficult tasks (Stevenson-Hinde, & Verschueren, 2002) and is often unavailable during emotional distress.
In the context of the Strange Situation, a child displaying avoidant attachment exhibits the following behaviors:
Possible Indifference to Being Alone: The text cuts off, but it seems to imply that distress does not occur when left alone for most babies with avoidant attachment. This indifference to being alone or with the mother reflects a lack of emotional connection or dependence on the mother.
C: Insecure Ambivalent / Resistant
The third attachment style Ainsworth (1970) identified wasinsecure ambivalent(also called insecure resistant).
When the mother returns, they are pleased to see her and go to her for comfort, but then they cannot be comforted and may show signs of anger towards her.
Here children adopt an ambivalent behavioral style towards the attachment figure. The child commonly exhibits clingy and dependent behavior but rejects the attachment figure when interacting.
The child fails to develop any feelings of security from the attachment figure. Accordingly, they exhibit difficulty moving away from the attachment figure to explore novel surroundings.
In the context of the Strange Situation, a child displaying anxious resistant attachment exhibits the following behaviors:
This combination of seeking closeness and resisting contact gives the impression of being ambivalent toward the mother, reflecting mixed feelings and confusion.
Conclusion
Ainsworth (1978) suggested the ‘caregiver sensitivity hypothesis’ to explain different attachment types.
Ainsworth’s maternal sensitivity hypothesis argues that a child’s attachment style depends on their mother’s behavior towards them.
For example, securely attached infants are associated with sensitive and responsive primary care.
Insecure-avoidant attachment is associated with unresponsive primary care. The child comes to believe that communication of needs has no influence on the mother/father.
For example, securely attached children develop a positive working model of themselves and have mental representations of others as being helpful while viewing themselves as worthy of respect (Jacobsen, & Hoffman, 1997).
Accordingly, insecure attachment styles are associated with an increased risk of social and emotional behavioral problems via the internal working model.
Theoretical Evaluation
caregiver sensitivity theory
They found that there is a relatively weak correlation of 0.24 between parental sensitivity and attachment type – generally more sensitive parents had securely attached children.
However, in evaluation, critics of this theory argue that the correlation between parental sensitivity and the child’s attachment type is only weak.
This suggests that there are other reasons which may better explain why children develop different attachment types and that the maternal sensitivity theory places too much emphasis on the mother.
Focusing just on maternal sensitivity when explaining why children have different attachment types is, therefore, a reductionist approach.
temperament
Babies with a ‘slow to warm up’ temperament (those who took a while to get used to new experiences) are likely to have insecure-avoidant attachments. Babies with a ‘Difficult’ temperament (those who eat and sleep irregularly and who reject new experiences) are likely to haveinsecure-ambivalent attachments.
In conclusion, the most complete explanation of why children develop different attachment types would be an interactionist theory. This would argue that a child’s attachment type is a result of a combination of factors – both the child’s innate temperament and their parent’s sensitivity towards their needs.
interactionist theory
Belsky and Rovine (1987) propose an interactionist theory to explain the different attachment types. They argue that the child’s attachment type is a result of both the child’s innate temperament and also how the parent responds to them (i.e., the parents’ sensitivity level).
Additionally, the child’s innate temperament may, in fact, influence the way their parent responds to them (i.e, the infants’ temperament influences the parental sensitivity shown to them). To develop a secure attachment, a ‘difficult’ child would need a caregiver who is sensitive and patient for a secure attachment to develop.
Meta-analysis
Madigan et al. (2023) conducted a comprehensive meta-analysis on 285 studies involving over 20,000 infant-caregiver pairs to estimate the global distribution of attachment classifications derived from the SSP: secure (51.6%), avoidant (14.7%), resistant (10.2%), and disorganized (23.5%).
Higher rates of avoidant and disorganized attachment were found in families with socioeconomic risks. Children who experienced maltreatment had extremely high rates of disorganized attachment (64%) compared to non-maltreated children (22%). Infants placed in foster or adoptive care showed less avoidant attachment but higher disorganized attachment versus biologically related dyads.
A notable finding was a temporal trend showing decreased avoidant attachment over time, perhaps reflecting changes in parenting styles or measurement. Regional differences were also found – Asia, Africa, and South America showed deviations from the North American distribution.
The meta-analysis provides a definitive estimate of the prevalence of secure infant-parent attachment globally (51.6%), supporting the notion that secure attachment is likely to occur when stressors and risks imposed on the parent-infant relationship are minimal.
However, more research is needed on cultural differences in attachment and validity of the SSP across diverse groups. The study also highlights factors like socioeconomic disadvantage and trauma that disrupt secure attachment formation.
Methodological Evaluation
reliability
The strange situation classification has been found to have good reliability. This means that it achieves consistent results. For example, a study conducted in Germany found that 78% of the children were classified in the same way at ages 1 and 6 years (Wartner et al., 1994).
validity
Although, as Melhuish (1993) suggests, the Strange Situation is the most widely used method for assessing infant attachment to a caregiver, Lamb et al. (1985) have criticized it for being highly artificial and lacking ecological validity.
The child is placed in a strange and artificial environment, and the procedure of the mother and stranger entering and leaving the room follows a predetermined script of eight stages (e.g., mum and stranger entering and leaving the room at set times) that would be unlikely to happen in real life.
I have been quite disappointed that so many attachment researchers have gone on to do research with the Strange Situation rather than looking at what happens at the home or in other natural settings—like I said before, it marks a turning away from “field work,” and I don’t think it’s wise. (Ainsworth & Marvin, 1995, p. 12).
The artificial environment of the SSP may not activate the attachment system for all infants, meaning some children could be misclassified (Ziv & Hotam, 2015). For example, avoidant infants may not actually feel stressed when separated from caregivers in this unfamiliar setting. Limited evidence exists linking avoidant behavior in the SSP to physical markers of stress.
Additionally, SSP classifications show only modest connections to expected correlates like maternal sensitivity.
A problem of the study is that it lacks population validity. The original study used American infants from middle-class families.
The study tells us about how this particular group behaves and cannot be generalized to the broader population andother cultures, which might behave differently towards their children and have different expectations.
For example, in Germany, parents encourage independence in their children, so they are less likely to show enthusiastic reunion behavior than children from other cultures.
Mary Ainsworth concluded that the strange situation could be used to identify the child’s type of attachment but has been criticized because it identifies only the type of attachment to the mother.
The child may have a different type of attachment to the father or grandmother, for example (Lamb, 1977). This means that it lacks validity, as it does not measure a general attachment style, but instead an attachment style specific to the mother.
In addition, some research has shown that the same child may show different attachment behaviors on different occasions.
Children’s attachments may change, perhaps because of changes in the child’s circumstances, so a securely attached child may appear insecurely attached if the mother becomes ill or the family circumstances change.
ethics
The strange situation has also been criticized on ethical grounds. Because the child is put under stress (separation and stranger anxiety), the study has broken theethical guidelinesfor the protection of participants.
However, in its defense, the separation episodes were curtailed prematurely if the child became too stressed.
categorial measurement
The categorical approach to classification may be too reductive to fully capture the complexity of infant attachment patterns (Ziv & Hotam, 2015).
Reducing attachment security to four rigid categories treats the SSP as a “weigh scale” reflecting a “true score” when attachment is likely more continuous and multidimensional.
This oversimplification could hamper the refinement ofattachment theoryif inconsistencies are attributed to limitations of the theory rather than the measure.
Infant attachment is complex, with individual differences likely being continuous rather than falling neatly into discrete categories.
Frequently Asked Questions
What are Mary Ainsworth’s contributions to psychology
Her work shaped our understanding of attachment styles: secure, avoidant, and ambivalent, greatly influencing developmental and child psychology.
How is the Strange Situation important?The Strange Situation experiment is important because it was a breakthrough in identifying different attachment styles in infants.Ainsworth’s research showed that how caregivers respond to a child’s needs can have a lasting impact on their emotional development. The experiment provided a reliable way to measure attachment styles, which has helped researchers and clinicians better understand how attachment influences a person’s relationships throughout their life.Ainsworth’s work has also influenced how parents and caregivers understand the importance of emotional responsiveness and sensitive care in promoting secure attachment and healthy child development.
How is the Strange Situation important?
The Strange Situation experiment is important because it was a breakthrough in identifying different attachment styles in infants.Ainsworth’s research showed that how caregivers respond to a child’s needs can have a lasting impact on their emotional development. The experiment provided a reliable way to measure attachment styles, which has helped researchers and clinicians better understand how attachment influences a person’s relationships throughout their life.Ainsworth’s work has also influenced how parents and caregivers understand the importance of emotional responsiveness and sensitive care in promoting secure attachment and healthy child development.
The Strange Situation experiment is important because it was a breakthrough in identifying different attachment styles in infants.
Ainsworth’s research showed that how caregivers respond to a child’s needs can have a lasting impact on their emotional development. The experiment provided a reliable way to measure attachment styles, which has helped researchers and clinicians better understand how attachment influences a person’s relationships throughout their life.
Ainsworth’s work has also influenced how parents and caregivers understand the importance of emotional responsiveness and sensitive care in promoting secure attachment and healthy child development.
Can a child’s attachment style change over time?Yes, a child’s attachment style can change over time. While attachment styles tend to be stable, experiences with caregivers and changes in the child’s environment can lead to shifts in attachment style.For example, a child with an insecure attachment style may become more secure with consistent and responsive caregiving. Conversely, a child with a secure attachment style may develop an insecure attachment style due to neglect, abuse, or other adverse experiences.
Can a child’s attachment style change over time?
Yes, a child’s attachment style can change over time. While attachment styles tend to be stable, experiences with caregivers and changes in the child’s environment can lead to shifts in attachment style.For example, a child with an insecure attachment style may become more secure with consistent and responsive caregiving. Conversely, a child with a secure attachment style may develop an insecure attachment style due to neglect, abuse, or other adverse experiences.
Yes, a child’s attachment style can change over time. While attachment styles tend to be stable, experiences with caregivers and changes in the child’s environment can lead to shifts in attachment style.
For example, a child with an insecure attachment style may become more secure with consistent and responsive caregiving. Conversely, a child with a secure attachment style may develop an insecure attachment style due to neglect, abuse, or other adverse experiences.
Is Ainsworth research ethnocentric?Ethnocentrismis when someone thinks their own cultural or ethnic group is the most important, and they judge other cultures or ethnic groups based on their own standards and values. They may see other groups as inferior or less important.Some researchers argue that Mary Ainsworth’s Strange Situation experiment isethnocentricbecause it was originally conducted on a relatively small sample of middle-class American families.Critics argue that the experiment may not represent attachment patterns in other cultures and may not account for cultural differences in child-rearing practices.
Is Ainsworth research ethnocentric?
Ethnocentrismis when someone thinks their own cultural or ethnic group is the most important, and they judge other cultures or ethnic groups based on their own standards and values. They may see other groups as inferior or less important.Some researchers argue that Mary Ainsworth’s Strange Situation experiment isethnocentricbecause it was originally conducted on a relatively small sample of middle-class American families.Critics argue that the experiment may not represent attachment patterns in other cultures and may not account for cultural differences in child-rearing practices.
Ethnocentrismis when someone thinks their own cultural or ethnic group is the most important, and they judge other cultures or ethnic groups based on their own standards and values. They may see other groups as inferior or less important.
Some researchers argue that Mary Ainsworth’s Strange Situation experiment isethnocentricbecause it was originally conducted on a relatively small sample of middle-class American families.
Critics argue that the experiment may not represent attachment patterns in other cultures and may not account for cultural differences in child-rearing practices.
What is the difference between secure and insecure attachment?
Secure and insecure attachmentsare broad classifications that describe how we think, feel, and behave in relationships.
References
Ainsworth, M. D. S. (1967). Infancy in Uganda: Infant care and the growth of love.
Ainsworth, M. D. S. (1979).Attachment as related to mother-infant interaction. In Advances in the study of behavior(Vol. 9, pp. 1-51). Academic Press.
Ainsworth, M. D. S., Bell, S. M., & Stayton, D. J. (1971) Individual differences in strange- situation behavior of one-year-olds. In H. R. Schaffer (Ed.)The origins of human social relations. London and New York: Academic Press. Pp. 17-58.
Ainsworth, M. D. S., Blehar, M. C., Waters, E., & Wall, S. (1978).Patterns of attachment: A psychological study of the strange situation. Hillsdale, NJ: Erlbaum.
Ainsworth, M., & Marvin, R. (1995). On the shaping of attachment theory and research: An interview with Mary D. S. Ainsworth.Monographs of the Society for Research in Child Development, 60(Serial No. 244), 3–24.
Ainsworth, M. D. S., & Wittig, B. A. (1969). Attachment and exploratory behavior of one-year-olds in a strange situation. In B. M. Foss(Ed. ),Determinants of infant behavior(Vol. 4,pp. 111-136). London: Methuen.
Belsky, J., & Rovine, M. (1987). Temperament and attachment security in the strange situation: An empirical rapprochement.Child development, 787-795.
Fox, N. A. (1989). Infant temperament and security of attachment: a new look.International Society for behavioral Development, J yviiskylii, Finland.
Jacobsen, T., & Hoffman, V. (1997). Children’s attachment representations: Longitudinal relations to school behavior and academic competency in middle childhood and adolescence.Developmental Psychology, 33, 703-710.
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Marrone, M. (1998).Attachment and interaction. Jessica Kingsley Publishers.
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Schaffer, H. R., & Emerson, P. E. (1964) The development of social attachments in infancy.Monographs of the Society for Research in Child Development, 29(3), serial number 94.
Stevenson-Hinde, J., & Verschueren, K. (2002).Attachment in childhood. status: published.
Thompson, R. A., Gardner, W., & Charnov, E. L. (1985).Infant-mother attachment: The origins and developmental significance of individual differences in Strange Situation behavior.LEA.
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Further Reading
Olivia Guy-Evans, MSc
BSc (Hons) Psychology, MSc Psychology of Education
Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.
Saul McLeod, PhD
BSc (Hons) Psychology, MRes, PhD, University of Manchester
Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.
