I often wondered what impact childhood stress had on a developing child’s brain, particularly during infancy. When my children were infants, I practiced co-sleeping, baby wearing, and attachment parenting. This created quite a bit of conflict with my ex-husband, who believed in sleep training. I am glad we are discussing this topic, as it seems that sleep training can be viewed as a type of ACE.
The ‘cry it out’ approach seems to have arisen as a solution to the dissolution of extended family life in the 20th century (Narvaez, 2011). The idea was, “a baby older than six months “should be taught to sit silently in the crib; otherwise, he might need to be constantly watched and entertained by the mother, a serious waste of time.” According to Narvaez (2011), “we know now that leaving babies to cry is a good way to make a less intelligent, less healthy but more anxious, uncooperative and alienated persons who can pass the same or worse traits on to the next generation”.
I recall during my Masters we studied the experiments on rats, called “Lick your Rats”. This study was eye opening, as it showed the effects of rats that are nurtured vs. those who were not nurtured. The researchers indicate that there are hundreds of genes affected by nurturance. In studies of rats with high or low nurturing mothers, there is a critical period for turning on genes and anxiety. “If in the first 10 days of life you have a low nurturing rat mother (the equivalent of the first 6 months of life in a human), the gene never gets turned on and the rat is anxious towards new situations for the rest of its life, unless drugs are administered to alleviate the anxiety (Naravez, 2011)”. When a baby gets distressed during sleep training, high levels are cortisol are secreted. It is thought that extreme stress and bouts of high cortisol can negatively influence neural development (Cassels, n.d.). In cases of severe neglect, effects are seeing the development of white matter in the brain, hippocampus and amygdala. The child can develop a “stress-reactive profile”, similar to the rats in the study, in which they have a heightened response to stress. Evolutionarily, this makes sense. An infant raised in an environment in which he or she is not safe has to be acutely aware of the stress around them (Cassels, n.d).
I found it interesting that although babies are typically more hyporesponsive to cortisol and stress, the responsiveness depends on the source of stress. In fact, separation from the caregiver happens to be one behavior that does elicit a cortisol response, especially if there is no other nurturing caregiver buffering the stress, such as another family member or babysitter. Essentially, this means that if the baby is left with a non-nurturing caretaker, the negative effects of the separation stress are more impactful. The behavior or circumstances that elicit cortisol spikes in infancy are moderate-severe pain, abuse, neglect, or abandonment of a caregiver with no responsive substitute. Sleep training falls well into this category.
Moreover, the infants and their mothers had lost what is called “synchrony”.This is the physiological link between mother and infant, the link that allows mothers to help soothe their babies when upset, the link that is associated with attachment status.
I am happy to say I continued to stand for what I believed in and I coslept with both my children. My daughter was a bit more needy, as I saw immediately in the early days we tried to sleep train. My motherly instinct took over immediately, and I coslept with her until she was 3 years old. To this day, she loves when I sleep next to her (at age 10). My son was a bit more independent, but he coslept for about 2 years. When I first separated from my ex-husband, we shared a family bed for about a year. I do not regret a moment of my decision.
“The functional effect of sensitive, responsive, attentive caregiving is that it allows children to express and experience distress, communicate those emotions to caregivers in ways that can elicit help, without stimulating increases in glucocorticoids” (Narvaez, 2011).
Cassels, T. (n.d.). “It’s Just a Little Cortisol”: Why Rises in Cortisol Matter to Infant Development. Retrieved (2018, May 29) from http://evolutionaryparenting.com/its-just-a-little-cortisol-why-rises-in-cortisol-matter-to-infant-development/ (Links to an external site.)
Narvaez, D. (2011, December 11). “Dangers of Crying It Out”. . Retrieved (2018, May 29) from https://www.psychologytoday.com/us/blog/moral-landscapes/201112/dangers-crying-it-out