Schaffer: Developed the stages of attachment theory. This theory describes the progression of attachment behaviours in infants as they develop specific attachments.
Lorenz: Conducted research on imprinting in animals, particularly geese. His work demonstrated that young animals have an innate readiness to form attachments with the first moving object they see, highlighting the biological basis of attachment.
Harlow: Famous for his studies on contact comfort in attachment using rhesus monkeys. His research showed that infant monkeys preferred spending time with a cloth 'mother' that provided comfort over a wire 'mother' that provided food, emphasizing the importance of emotional comfort in forming attachments.
Bowlby: Developed the theory of maternal deprivation, which emphasizes the significance of a continuous and loving attachment with a primary caregiver (mother figure) for normal emotional and intellectual development. He proposed that prolonged separation from the primary caregiver during the critical period can have severe negative consequences. He also drew on evolutionary theory to suggest that attachment is an innate and adaptive behaviour that has evolved to ensure survival.
Ainsworth: Developed the Strange Situation, a standardized procedure used to assess the quality of attachment between infants and their caregivers. Through her observations, she identified three main attachment types: secure attachment, insecure-avoidant attachment, and insecure-resistant attachment.
Researchers of Romanian orphan studies: These studies investigated the effects of institutionalisation on children who experienced severe deprivation in early life. While specific researchers are not named in the initial overview, the impact of their work in highlighting the negative consequences of a lack of attachment is emphasized. Later revision summaries mention Rutter et al. (2011) and Zeanah et al. (2005) as conducting research on Romanian orphans. These studies examined the extent to which the negative effects of early institutionalisation could be reversed by subsequent good quality care.
Rutter et al. (2011): Research on Romanian orphans showed that many of the negative effects of early institutionalisation, such as cognitive impairment and attachment difficulties, could be overcome if children were adopted before six months old.
Zeanah et al. (2005): Another study on Romanian orphans assessed attachment type in children who had spent most of their lives in institutions compared to a control group of children who had been raised in families.
Hodges and Tizard (1989): Conducted a longitudinal study on the effects of institutionalisation, following children who had been in residential nurseries until they were adopted, returned to their biological mothers, or remained in care. Their findings shed light on the long-term social and emotional outcomes for these children.
Quinton et al. (1984): Studied women who had been raised in institutions and compared them to women raised in stable homes. The research found that the women who had experienced institutional care had greater difficulties in their adult relationships and as parents.
Koluchova (1976): Presented a case study of identical twin boys who experienced severe isolation from infancy until they were seven years old. Despite their early privation, the boys showed remarkable recovery after receiving loving care, challenging the idea that the effects of maternal deprivation are always irreversible.
Shaver and Hazan (1988): Extended attachment theory to adult romantic relationships, proposing that early attachment experiences influence the nature of adult attachments. They used a "love quiz" to assess participants' attachment styles and their relationship experiences.
Myron-Wilson and Smith (1998): Investigated the relationship between childhood attachment types and involvement in bullying. They found that insecure-avoidant children were more likely to be victims of bullying, while insecure-resistant children were more likely to be bullies.
Kerns (1994): Found that securely attached children tend to develop better quality childhood friendships.
Bailey et al. (2007): Investigated intergenerational patterns of attachment. Their research on mothers and their own mothers found evidence supporting the idea that mothers' attachment type tends to be similar to that of their own mothers, suggesting a transmission of attachment patterns across generations.
Hazan and Shaver (1987): Pioneering work in applying attachment theory to adult relationships, suggesting that adult romantic relationships are characterized by similar attachment styles as those seen between infants and caregivers.
Zimmermann (2000): Conducted a review of research on attachment and concluded that attachment type is not as stable as suggested by early research and can be influenced by later life events.
Main and Solomon (1986): Conducted further research using the Strange Situation and identified a fourth category of attachment: disorganised attachment. This type is characterised by a lack of consistent strategy in dealing with separation and reunion episodes.
Fonagy et al. (2002): Explored the role of mentalization (the ability to understand one's own and others' mental states) in attachment security, suggesting that secure attachment is associated with a well-developed capacity for mentalization.
Howe (1995): Provided a comprehensive review of attachment theory and research across the lifespan, highlighting its wide-ranging implications.
Tronick et al. (1992): Conducted the "still-face" experiment to study caregiver-infant interactions. They observed infants' reactions to their mothers suddenly becoming unresponsive and still-faced, demonstrating the importance of reciprocal interaction for infant well-being and attachment development.
Maccoby (1988): Summarized research on the role of the father in attachment, suggesting that fathers can form secure attachments with their infants and that the quality of the father-infant attachment can be influenced by factors such as the father's sensitivity and the mother's attitude towards the father's involvement.
Grossman and Grossman (1991): Found that German infants showed higher rates of insecure-avoidant attachment compared to infants in other cultures. They suggested this might be due to German child-rearing practices that emphasize independence and early separation.
Takahashi (1990): Studied attachment in Japanese infants using the Strange Situation. They found a higher rate of insecure-resistant attachment and very few insecure-avoidant infants, possibly reflecting Japanese cultural norms of close mother-infant proximity and reluctance towards separation.
Van Ijzendoorn and Kroonenberg (1988): Conducted a meta-analysis of numerous cross-cultural studies using the Strange Situation. Their findings indicated that while there were cultural variations in the distribution of attachment types, secure attachment was the most common pattern across all cultures studied, supporting the idea that secure attachment may have a universal basis.