Neurobiology and Attachment
by Linda M. Ikeda, R.N., MFT
This is quite the exciting field at present and we are blessed to have many researchers focusing on this area. Allan Schore, Bessel Van der Kolk, and Bruce Perry are neuroscientists who have done pioneering work as to how trauma affects the developing brain. They remind us that the brain develops in a predictable fashion from the most primitive or reptilian brain to the most complex, the cerebral cortex. Normal patterns of development of the neuronal systems and the functions they mediate require specific patterns of activity-specific signals, at specific times during development. These "critical periods" are windows of vulnerability during which the organizing systems are most sensitive to environmental input, including traumatic experience.
Optimal development of more complex systems, i.e., the cortex, requires healthy development of less complex systems, i.e., the brainstem and midbrain. These brain systems develop in a sequential fashion, from brainstem to cortex. Therefore, if the brainstem develops in less than optimal fashion (such as following excessive traumatic experience) this will impact the development of all other regions of the brain. The brain remains sensitive or "plastic" throughout all of life but different parts of the brain are more plastic (cortex) and others are relatively less plastic (the brainstem). The good news is that experience can change the mature brain. The bad news is that experiences during the critical periods of early childhood, organize the brain system! (Bruce Perry)
I first heard the term "Complex PTSD" (post-traumatic stress disorder) in a seminar given by Bessel Van der Kolk. Complex PTSD is foundational trauma occurring during early brain development, and all subsequent brain development occurs "on top of" this early trauma and in reference/deference to it.
Interpersonal relationships impact the way that the brain develops. Neglect actually results in certain parts of the brain developing in a less favorable manner. These are ideas I hope to develop further with the work of Daniel Siegel.
Daniel Siegel has served as a National Institute of Mental Health research fellow at UCLA where he studied family interactions, with an emphasis on how attachment experiences influence emotions, behavioral regulation, autobiographical memory and narrative processes. He wrote an excellent book called THE DEVELOPING MIND: How Relationships and the Brain Interact to Shape who we Are (Guilford Press, 1999). (The remainder of the article will be based on this book.) In it he states that, "From a basic biological perspective, the child's neuronal system, the structure and function of the developing brain, is shaped by the parent's more mature brain. This occurs within 'emotional communication.' The attunement of emotional states provides the joining that is essential for the developing brain to acquire the capacity to organize itself more autonomously as the child matures (p. 278). Attunement means "to be in tune with, in synchrony with, or following the baby's expressions, being sensitive to her needs rather than demanding that she be sensitive to mine. Seeking proximity to a caregiver and attaining face-to-face communication with eye gaze contact is hardwired into the brain from birth: it is not a learned behavior! Babies are created to seek eye contact! Babies' visual fields in early infancy are about the distance from a mother's breast to her face. The first distinguishable patterns seen by infants are the contrast of dark and light, which pretty well defines the mother's eyes!
Siegel explains that by about 18 months, the frontal parts of the child's brain are developing rapidly. This enables her to have evocative memory in which it is believed she is able to bring forward in her mind a sensory image of a parent in order to help soothe herself and regulate her emotional state. These are the "structures," the internal representations of the self, which we've heard so much about in various psychological theories.
In the case of depressed mothers, there is a marked decrease in shared positive affect states, and the infants (and their mothers) are seen as withdrawn. When this occurs, there is a marked decrease in left frontal activation in both. Isolation and emotional distance take their toll and the infant's intense emotions and enjoyment in life may be severely muted and her "mind-sight" (which Siegel defines as the ability to sense the subjective mental life of others, or of oneself) may also be severely restricted. This may result in difficulty getting her basic emotional needs met throughout her life.
Children who experience severe emotional deprivation during early brain development may be at most risk of having losses in the structural components of their right hemispheres, especially in the region of the orbitofrontal cortex. This vulnerability may be understood as a function of the primary role of the right hemisphere in mediating the affect attunement that serves as a major form of connection and communication between the child and caregiver. When we examine the functional properties of each hemisphere, especially the right hemisphere, we begin to gain insight into the differences between individuals with different attachment experiences.
Siegel concludes that secure attachment can be seen as a developmental relationship that provides for an integration of function of the two hemispheres, both between child and caregiver, and within the child's own brain. "When the dyad are interacting they become more than just A and B: AB is a whole new super-system and affects both A and B. If A is an adult and B is a baby, then the pattern of responses will shape the function and the developing structure of B's immature brain, not merely B's present state of mind." (p. 232)
He goes on to say that; "an infant who has a healthy secure attachment has had the repeated experience of nurturing, perceptive, sensitive, and predictable care giving responses from her mother which have been encoded implicitly in her brain. She has developed a generalized representation of that relationship — a mental model of attachment — which helps her know what to expect from her mother. Given that these repeated experiences have been predictable, and that when there have been disruptions in mother-infant communication the mother has been relatively quick and effective at repairing the ruptures, this fortunate infant has been able to develop a secure, organized, mental model of her emotional relationship." (p. 32)
Because our brains are "experience expectant," the infant's implicit memory anticipates that the future will continue to provide such contingent communication. Alternatively, the infant who has experienced less than optimal attachment will anticipate that the future will continue to provide more of the same.
Attachment provides a framework for adaptation to life experiences: security conveys resilience, whereas insecurity conveys risk. Van Ijzendoorn's meta-analysis of the Adult Attachment Interview indicated that in psychiatric populations, insecurity is far more prevalent and security is far less prevalent than in the general population. By itself then, adult or child attachment classification is not synonymous with pathology but should be viewed as an organizational component of the mind that provides flexibility and adaptability with security — or, in contrast, rigidity, uncertainty, disorganization and disorientation, with insecure [attachment]." (p. 87)
This reflection on mental states is more than a conceptual ability; it permits the two individuals' minds to enter a form of resonance in which each is able to "feel felt" by the other. This inter-subjective form of connection is manifested both in words and in non-verbal aspects of communication. Daniel Siegel reports findings about the most important factor in relationship health, across cultures, are this experience of contingent communication or feeling felt.
Main and Goldwyn have suggested that the way adults can flexibly access info about childhood and reflect upon such info in a coherent manner determines their likelihood of raising securely attached children. In other words, the ability to reflect upon one's own childhood history, to conceptualize the mental states of one's parents, and to describe the impact of these experiences on personal development are the essential elements of coherent adult attach narratives (p. 312). What is being said here is that in interviewing a pregnant woman, if she is able to give a coherent and cohesive narrative of her childhood, this is the single most powerful and consistent predictor of her child having a secure attachment! It is important for parents to work on their "stuff," if they are going to raise securely attached children.
"The left hemisphere's drive to understand cause-effect relationships is a primary motivation of the narrative process. Coherent narratives, however, require participation of both the interpreting left hemisphere and the 'mentalizing' right hemisphere. Coherent narratives are created through inter-hemispheric integration." (p. 331)
In fact, storytelling may be a primary way in which we can linguistically communicate to ourselves and others, the sometimes hidden contents of our implicitly remembering minds. Stories make available perspectives on the emotional themes of our implicit memory that may otherwise be consciously unavailable to us. This may be one reason why journal writing and intimate communication with others, which are so often narrative processes, have such powerful organizing effects on the mind. (p. 333)
"Experience…activates neurons in such a manner that genes may become expressed and may produce alterations in neuronal connectivity…We can propose that the creation of new neuronal linkages, then, allows the internal constraints of the dynamical system of the brain to change. New interconnecting neuronal linkages may thus serve to integrate not only anatomically independent processes, but functionally isolated ones such as engrained mental states that have produced inflexibility and impairments in the system's capacity to adapt." (p. 306) "Genetic potential is expressed within the setting of social experiences, which directly influence how neurons connect to one another. Human connections create neuronal connections." (p. 85) In other words, there are times when relationship connection actually activates (or not) a gene. Neuroscientists are fond of saying that "neurons that fire together wire together" and that "neurons that fire apart wire apart."
"The capacity for self-integration, like the processes of the mind itself, is continually created by an interaction of internal neuro-physiological processes and interpersonal relationships." (p. 314)
This is new information as it was previously thought that very little changed in the brain, after six years of age.
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