Lecture 7 – 03-01-12
Parenting is bizarre; the fact that many of us will just be handed some little creature at some point to
take care of; you suddenly are the sole responsibility, it’s non-stop consistent demand. The impact of it
on your psychology, we don’t really know what really happens.
Does biology come up with mechanism that helps parenting? Today we just want to consider whether
that’s a possibility.
All of the stuff we’ve been looking at so far focused on one type of parenting. There are specifics we can
look at with regards to parenting behaviours.
London Taxi Study
The hippocampus (navigation and spatial relation) is a little bigger for certain people. Experience
does sculpt and change specific parts of the brain that are used for specific tasks. The model that the
brain is really a muscle; that’s more than a metaphor, it’s pretty true.
It’s possible that there may be major changes in the brain that are allowing you to better interact with
your child. There’s a huge wave of hormonal change with pregnancy.
London taxi video
They must create intricate mental map of landmarks and location. For 150 years every new cab driver
has to pass a gruelling exam – “the knowledge” – for people to look at how the brain adapts and reacts.
Hippocampus must be the key to success. Direct experience is an essential part of the training. How
does the brain retain all that ordre and information? Part of the hippocampus was larger in these drivers.
The hippocampus has a spatial map in it for the cab drivers. The increase in knowledge allows the
hippocampus to grow bigger. This study suggests that the adult brain can refashion itself.
You really get engaged in learning something, is there something really happening?
This is problematic. It could be that if you got this huge hippocampus, you may be a person that wants
to be a taxi driver. The more that you were driving, the bigger that side of the hippocampus was.
Maternal Brain Circuit
What has biology given people to become parents? It’s possible that our brains are changing
structurally. If the hardware is changing, you can imagine that the function and operation is changing as
well. Hormones can start to change the hormones and number of synapses that are produced in the
brain. We just didn’t know that experience of doing something could cause those changes.
Can some changes in hormones actually affect behaviour and we already got a taste of this
seeing that during pregnancy when you get a rise in oxytocin, that predicts how you parent.
Parent Cortisol Inconsistent
In the 3rd trimester, the amount of stress hormone you have predicts the behaviour negatively.
The relationship between cortisol and behaviour is not the same. More cortisol, more positive behaviour,
more stress behaviour. In this first study we saw that more cortisol you had, less oxytocin, less parenting
you show. After you give birth, how much coritsol you have in your system when you’re sitting down,
the level cortisol in your system predicts the amount of parenting you do. There are different kinds of
relationship between cortisol and parenting. Parents like the smell of the child more if there’s more
cortisol, they show greater sympathy when it cries.
We have to figure out when is the appropriate time to have that amount of cortisol. This is what
we got to figure out.
Maternal Cortisol and Maternal Responsiveness in Yellow Baboons
The more cortisol you have the more responsive you are to your child (Fleming); prenatally vs.
Left graph (Prenatal) – glucocorticoids we also call cortisol. There has been different ways of
measuring it. You have to figure out ways on how to get saliva in the wild from animals like we do with
humans. Prenatally there is an association. The more these mothers had these glucocorticoids the more
responsive they were with their child significantly.
Right graph (postnatally) – the amount of cortisol in the feces does not predict that same
Specific types of parent behaviour
In reality, there may be a lot more going on about how parents behave. When you’re interacting
with the child, they may engage with the child. Others will do a lot of responsiveness with the child’s
behaviour i.e. mirroring, imitating. A more subtle type of behaviour is when there’s this reciprocal
imitations i.e. peekaboo. The child will instigate in a game and make that a mutual experience. Are any
of these specific behaviours associated more with the cortisol in the parent?
You take a group of parents you want to know how much of the time they are watching, or
mirroring of the child, etc. The amount of watching and the more sophisticated style, the imitation, it’s
the smallest proportion of time spent with the child. The parent is usually trying to get the child’s
attention. The parent is initiating and has the child interact and engage in reciprocal contact. We have to
keep that in mind when you’re thinking about the relationship with cortisol and the parental behaviour.
Prototypical parent-infant interaction profiles
During normal interaction, the parent will show fair amount of responsiveness. After some kind
of big emotional event, you’ll see the parent just do the potential listening i.e. when the child is upset.
They just try to get the child’s attention and reconnect.
Another group strangely did the opposite. When the upset-ness comes, the parent poured on
the nice responsiveness. Which one is better?
When you are interacting with the child what happens with stress response? There is a huge
decrease in cortisol. Interacting with your child is good for the parent.
Associations Among variables
We don’t find much significance in cortisol of parent watching, etc. But, parents sitting in the
chair have higher levels of cortisol compared with the “responsive” parents.
Contingent Responsiveness by Infant Affect
Is the kid happy or not happy? When you’re taking care of something, you’re trying to get their
attention, but you don’t get their attention, how do you get this child taken care of? You can imagine
that that has a big impact on the parent’s level of stress.
Low positive effect or high positive effect; if the kid’s happy the parent is more responsive to
When you’re a parent just sitting down, more basal cortisol potentially makes you more
involved. The question is, can we identify a group of parents that reflects the most responsive
If you are one of these parents that has high level of basal cortisol and you have a kid who has
high positive effect, that’s the magic combination for being most responsive to the child.
Summary about parents
If the kids are really happy the parents will have elevated basal cortisol and they will be more
responsive with the child. When we want to predict who is going to the most contingent, it’s by looking
at the combination of who has high basal cortisol and who has the happy kid? That’s sort of the positive
side of cortisol. When does it become a threat? Is it maybe when you’re interacting with that child,
you’re doing a lot of attention eliciting, you’re not getting thru to the child, it’s that you may go up. If
your cortisol levels increase, then some of these attention eliciting behaviours will change.
We want to know about the feedback of HPA Axis. We know that when you have a stress
response, the cortisol causes a part of the HPA axis to shutdown. There are specific types of stress
receptors in the body that cortisol targets. We have a different system