The Strange Situation Test: Ainsworth's Attachment Theory for Infants

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  • 2:07 The Strange Situation
  • 4:38 Secure Attachment
  • 5:32 Resistant Attachment
  • 6:35 Avoidant Attachment
  • 7:14 Disorganized-Disoriented
  • 8:01 Lesson Summary
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Lesson Transcript
Instructor: Melissa Hurst
The attachment and bonds infants develop early in life play a critical role in their interactions with others as they grow. This lesson will introduce the Strange Situation experiment conducted by Mary Ainsworth and discuss the four infant attachment types identified through the experiment.

Infant and Child Anxiety

Have you ever approached an infant or young child of a colleague or friend that you have never met? Did that child appear apprehensive and anxious? Perhaps the child even hid behind the leg of his or her parent or cried when you approached. This behavior is very typical and expected among infants and young children.

The psychologist Mary Ainsworth explained this behavior through an attachment theory. Attachment is defined as a deep and long-term bond that connects one person to another. Ainsworth and her colleagues conducted an experiment to assess the security of attachment in infants and young children. This experiment sought to observe separation and stranger anxiety and also determine the different types of attachment styles exhibited between children and their primary caregiver.

Separation anxiety is the stage in which a child experiences anxiety, such as fretfulness and wariness, when separated from the primary caregiver. Separation anxiety typically appears when infants are forming attachments around 8 months of age and peaks at approximately 14-18 months of age. Over time, this type of anxiety becomes less frequent and less intense, especially when children feel safe in their home environment and trust that the caregiver will return. In extreme cases, separation anxiety can cause a child to refuse to go to school or other places for fear of separation and refuse to go to sleep without the caregiver being nearby.

Stranger anxiety is the reaction to a stranger that may cause a child to become quiet, wary of the person, or hide. Stranger anxiety is common among children between the ages of 8-18 months. Stranger anxiety typically declines as the child approaches the age of 2 years old.

The Strange Situation Experiment

The Strange Situation experimental procedure was developed by Ainsworth and her colleagues in the 1970s. The procedure was developed in order to measure the quality of infant attachments in 1-2 year olds. The experiment sample consisted of approximately 100 middle-class American families.

The procedure consists of 8 separate yet continual episodes that gradually escalate the amount of stress infants experience as they react to the approach of an adult stranger and the departure and return of their caregiver. Through these episodes, the researchers identified 4 types of infant attachment: secure, resistant, avoidant, and disorganized-disoriented, which we will discuss in detail later in this lesson.

The Strange Situation proceeded as follows:

  • Episode 1: An experimenter leaves the parent or caregiver and baby alone to play.
  • Episode 2: The parent sits while the baby plays. Researchers observed the use of the parent as a secure base in this episode.
  • Episode 3: A stranger enters the room and talks to the parent. Researchers observed stranger anxiety in this episode.
  • Episode 4: The parent leaves the room and the stranger stays, letting the baby play and offering comfort if necessary. Researchers observed separation anxiety in this episode.
  • Episode 5: The parent returns, greets the baby, and offers comfort if needed, and the stranger leaves the room. Researchers observed the reactions to reunion during this episode.
  • Episode 6: The parent leaves the room again. Only the baby is in the room. Researchers are again observing separation anxiety.
  • Episode 7: The stranger enters the room and offers comfort to the baby. Researchers are observing stranger anxiety and the ability of the baby to be soothed by a stranger.
  • Episode 8: The parent returns to the room, greets the baby, and offers comfort. The baby is allowed to return to play. Researchers observed the reactions to reunion in this final episode.

Attachment Types

Secure Attachment

Ainsworth and colleagues identified 4 types of infant attachment through observations of the Strange Situation: secure, resistant, avoidant, and disorganized-disoriented.

The most common type of attachment is labeled as secure attachment. Approximately 60-65% of infants and young children in our society are labeled as securely attached to their parents or primary caregivers.

The securely attached infant actively plays and explores the room when his parent is in the room because he or she serves as a secure base. The infant may be upset when the parent leaves but greets his parent happily and is comforted by the parent's presence when he or she returns. The securely-attached child is friendly and outgoing with strangers when the parent is present.

Resistant Attachment

Another type of attachment is resistant attachment. Approximately 10% infants and young children show a resistant attachment. This is observed as an insecure attachment characterized by anxious, ambivalent reactions. The child that is characterized with this type of attachment does not explore and play, even when his parent is in the room. The parent appears to not serve as a secure base for exploration and play.

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