This is a continuation of my previous post, which analyzes the claims brought up in this poster by Macall Gordon, a psychology graduate student who maintains there is no proof CIO techniques are safe before a baby is a year old.
claim #4: extinction has been shown to be stressful in animal studies, in which animals subjected to experiments involving behavioral extinction showed persistent elevations of cortisol.
The mere fact that extinction (that is, the cessation of a reward after a subject responds to a stimulus in a way that formerly entitled him to one – in our case, crying having caused the parent to pick up and soothe the baby) involves stress, does not necessarily mean the stress is so severe or persistent that any significant negative changes happen in the infant’s brain. In fact, it appears that moderate increases in cortisol at the right time of day (usually late afternoon/early evening) may actually help increase learning and memory retention in human children (here’s another study demonstrating this in infants).
I wouldn’t be at all surprised if CIO was found to be an acute stressor in some or all children, this is spite of the fact that in studies done on human infants undergoing extinction (Lewis & Ramsay, 2005; Lewis, Ramsay & Sullivan, 2006), the infants displayed either anger, sadness or a combination; anger did not involve cortisol elevations, whereas sadness did. I might add that my own children, when undergoing CIO, sounded a lot more angry and outraged than sad and despairing.
But even if CIO is an acute stressor, is it a given that any acute stress will cause the infant’s brain to be altered forever, making him susceptible to a host of future psychological maladies?
There seems to be a lot of conflicting studies out there, but in general, it seems that older children and adults who have been, consistently, and from early on in their lives, subjected to stressful events, undergo a down-regulation of their HPA (hypothlamic-pituitary-adrenal) axis. In other words, the persistently high levels of cortisol they were exposed to as a result of the early stress – usually on the level of maltreatment, institutional care, parental psychopathology or severe family strife – caused the HPA axis to be less responsive. Thus, people with such a past generally have low morning cortisol levels and reduced HPA axis activity over the day. This pattern is hypothesized to be a risk factor in the development of future psychopathology, though causation has not yet been proven. In any case, though, if CIO were to have any long-term adverse psychological effects, the least we’d expect to see is the emergence of such a pattern in children who underwent CIO who are followed long-term (and you’d have to compare the HPA axis profiles before and after CIO to be able to claim CIO was a cause of this pattern).
So far, nobody has actually examined this. But given that CIO is not a chronic stressor (as it lasts for a few nights only, the parents are popping in periodically, and during the day the infants are treated as usual), it’s a priori highly unlikely. I would also point out that later supportive, loving care (such a given by most parents before, during and after CIO initiation) has been shown to restore imbalances in the HPA axis in 3-6 year old children in foster care (Fisher et al, 2007). How much more so in a younger infant in a loving family situation?
Claim #5: CIO is not evaluated in context of the nightwaking, parental pscyhological issues, and the way parents may act toward their babies afterwards.
At least that’s what I gleaned from the psychobabble under “Rethinking CIO: Infant mental health perspectives are needed.” Gordon is operating under the AP assumption that nothing less than unconditional, constant parental responsiveness will produce a mentally healthy baby, and that “baby training” is something to be avoided at all costs. Back in the real world, we don’t actually have any evidence that temporary unresponsiveness (or rather, hyporesponsiveness) has any long-term negative effects on the child. Babies have been CIO’ed in much harsher ways in the past, but despite this, do not seem to have produced generations of serial murderers.
As to whether CIO is inappropriate in the context of parental psychopathology – there is no discussion of the beneficial psychological effects on parents (especially mothers) getting a decent nights’ sleep, and the improvement in family dynamics as a result, as discussed here.
I might add that in Hiscock et al, one of the studies demonstrating no harm from CIO in infants, it would seem that most mothers who used behavioral interventions to get their infants to sleep reported that their relationship to their child had improved as a result:
Fifty-five mothers in the intervention group reported on how the infant sleep management strategies had affected the relationship quality with their child. Mothers strongly endorsed both behavioral interventions, with 84% (46 of 55) rating these as having had a positive effect on their relationship with their child.
There is a tiny possibility that the rare extra-sensitive child with self-regulatory issues will be affected by CIO (what Orac at Respectful insolence calls “the incredible shrinking causation claim”). But I would expect such children to not respond to CIO, rather than learn to sleep through the night and become depressed monsters (mainly because nobody has actually come up with a credible description of such an event). Ditto for a child whose nightwaking is a result of physical or psychological issues. But absent any evidence CIO harms any baby, I think we can set this claim aside until the potential for harm is actually shown.