Perinatal Neuroscience

This is an excerpt out of a talk delivered by Dr Neil Bergman (his website is www.kangaroomothercare.com) and shared with me by a Lactation consultant.

Skin-to-Skin Contact and Perinatal Neuroscience
Bergman N. J. MB ChB, MPH, MD, Capers Breastfeeding Seminar 2006.


Breastfeeding: A Lifelong Investment

Basic mechanisms for brain growth
Schore presents a new slant with the same message in two recent in depth reviews from developmental psychology, infant psychiatry and developmental neuroscience(3;4;4). The development, growth and function of the human brain has been studied extensively in the last decade, and in the following section some 40 pages are summarised in a few quotes (verbatim):
“Maturation of … adaptive right brain regulatory capacities is experience dependent, and this experience is embedded in the attachment relationship between infant and primary caregiver, …“ … the environment affects the structure and function of the brain.
“ …an early postnatal period represents a “critical period” of limbic –autonomic circuit development, during which time experience or environmental events might participate in shaping ongoing synapse formation.” (Bowlby)
The capacity to cope with change and stress is a right brain function, which is built up over time. After birth, the critical neural pathway that develops is the amygdala-orbitofrontal tract, and the salient stimulation or experience required is tactile:
State organisation refers to the organism’s level of alertness, and ranges from deep sleep through several stages to awake and at the extreme “hard crying”. Critical for the well-being of a newborn is the requirement of “cycling” appropriately between levels of sleep that is not too deep, and being awake for feeding, and avoiding crying and stress. Optimal synaptogenesis and wiring is related to normal sleep cycling. Electroencephalographic recordings have shown that the normal sleep cycling of a newborn is 60 to 90 minutes, and disruption of this cycling leads to stress and pathology. This kind of optimal state cycling is only observed in infants that are together with their mothers, and optimally so where there is maximal skin-to-skin contact.(14;15;15-17)
The pattern of breastfeeding that results when an infant is never separated from the mother is very different from that we believe to be “normal” in our western culture. Firstly – the pattern is entirely determined by the infant and not the mother, and each infant is unique. An infant allowed to decide its own feeding pattern from initiation will settle in to “maintenance” feeding, and will feed every hour or two at most, will ingest the full ejection load of a single let down reflex, which just happens to be the comfortable maximum capacity of its stomach, and which happens to contain enough food and calories for one or two hours at most, and it will cycle its state organisation effectively. This is the pattern observed from almost all non-western cultures.(18)
Consequences of adverse environment on brain growth
Removed from the correct habitat, all mammals exhibit an identical pre-programmed response, referred to in biology as the "protest - despair response"(6). This is the defence programme, and has its own set of hormones, autonomic controls and somatic expressions. The “protest” response is one of intense activity seeking reuniting with the habitat/mother, the “despair” response is a withdrawal and survival response of decreased temperature and heart rate, mediated by a massive rise in stress hormones. Reunited with the correct habitat (mother), there is a rapid rise in heart rate and temperature.
The "protest-despair response" was first described in humans, in orphans after WWII(3;4) , it was subsequently studied in monkeys and then in many other mammals. Separation has been shown to cause maladaptive changes in brain structure and subsequent behaviour, and changes in the fundamental efficiency of all the body systems(8). Early separation produces major shifts in susceptibility to stress-induced pathology(2). The origins of many human behavioural deviations are unknown, it has been suggested that most of these can be traced back to “violations of an innate agenda?"(10) The primary violation, the worst case scenario, to any newborn is separation from its habitat/mother.
In current neurobehaviour studies in human beings, protest-despair is referred to as “hyperarousal and dissociation”. This work is summarised in the long but illuminating psychoneurobiological review by Allan Schore(4).
“…the human infant’s psychobiological response to trauma is composed of two separate response patterns – hyperarousal and dissociation. (Perry et al)
“…(In hyperarousal) the sympathetic autonomic nervous system is suddenly and significantly activated, increasing heart rate, blood pressure, tone and vigilance, distress is expressed in crying then screaming…this state of “frantic distress”, or what Perry terms fear-terror, is known as ergotropic arousal…with excessive levels of major stress hormone releasing factor…resulting in a hypermetabolic state in the brain.
“(Dissociation) is a second later-forming reaction in response to terror, and involves numbing and avoidance…a state of conservation-withdrawal, a parasympathetic regulatory strategy that occurs in helpless and hopeless situations … a hypometabolic process used throughout the lifespan, in which the individual passively disengages “to conserve energies” … to foster survival by the risky posture of feigning death.
“In this passive state of profound detachment, pain numbing and blunting endogenous opiates are elevated, instantly triggering analgesia and immobility and inhibition of cries for help … vagal tone increases dramatically, decreasing blood pressure and heart rate … in this state both the sympathetic energy-expending and parasympathetic energy-conserving components of the infant’s developing brain are hyperactivated … (creating) chaotic biochemical alterations, a toxic neurochemistry in the developing brain
“ … the psychotoxic contexts of early relational trauma … intense relational stress alters calcium metabolism, a critical mechanism of cell death … result in permanent alterations in receptors … (causing ) high risk for developing severe psychopathologies at later stages of life.”
Neurobehavioural evidence of environmental deprivation
Prematures and newborns have a nervous system which lacks the ability to dampen down sensory signals. Over-stimulation of any of the senses will be experienced as PAIN by the newborn. Stress hormones increases the perception of pain. When the entire environment provides noxious stimuli to the developing brain, the effects or early abuse and neglect have catastrophic impact(4).
“Severe levels of stress associated with infant abuse and neglect are pathogenic to all immature human brains, and neglect may be even more detrimental than abuse.
“Caregiver induced trauma is qualitatively and quantitatively more potentially psychopathogenic than any other stressor …
“In human infancy, relational trauma, like exposure to inadequate nutrition during brain growth spurt, biological pathogens or chemical agents, and to physical trauma to the baby’s brain interferes with the experience dependent maturation of the brain’s coping systems, and have a long-enduring negative impact on the trajectory of developmental processes.
Birth complications … affect personality, relationships, self esteem … and behaviour patterns later on in life”(13). "The origins of many behavioural deviations are unknown ... can some be traced back to violations of an innate agenda?" Maternal rejection and lack of bonding combined gives a strong correlation to violent criminal behaviour. Advent of hospital nurseries and early separations correlates with attachment disorders, maternal abandonment of baby, increased addictive behaviours (unmet oral needs).
In short, separation of mother from infant is psychotoxic for the infant’s brain.


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