Cool new child development research!
I've had a packed couple of weeks hearing about a lot of interesting science and psychology research! I went to the Society for Research in Child Development (SRCD) conference in Austin, TX, where I heard many fascinating research findings, got to hang out with friends in the area, and ate my weight in barbecue and donuts. I love conferences for the cool new science, but it doesn't hurt when you can turn it into a mini-vacation!
Enough with the donuts -- Back to the research!
Here are some snippets of talks by researchers that I heard at SRCD. Since many of the results aren't published yet, most don't have the citations I typically put in these articles. Conferences are a place to share the latest research, which may not have had time to going through the extensive review by other scientists and the journal publishing process.
I organized the findings by topic so you can bounce to what interests you!
A large study of children and adolescents sponsored by NIH studied how boys and girls think and regulate their emotions over time. The study showed that both boys and girls got better at thinking tasks that don't involve emotions as they go through puberty (like reasoning or holding information in your memory). However, it appears that males got better at regulating their emotions across puberty while females got worse. I wasn't sure what to make of this finding. Maybe males and females even out in their emotion regulation over time. Or maybe this difference between males and females in emotion regulation puts us at risk for different kinds of mental health problems. For example, women are more likely to develop depression and anxiety, while men are more likely to have problems with overt and physical aggression. I would love to see what happens to emotion regulation if we follow these adolescents into adulthood!
A prominent child development researcher stressed that when thinking about alcohol and drug use and other risky behavior in adolescents, researchers should think less about focusing on just stopping "bad" behavior since that's overly simplistic. We should think about how adolescents' thoughts, emotions, their ability to regulate their own behavior all work together to produce both risky and positive behaviors. Behavior is complicated, and there are so many factors that go into how we behave, so we should examine it very carefully if we want to understand it. We also need to think about how pubertal hormones (like testosterone and estrogen) affect our emotions, learning, and our motivation to behave certain ways across puberty (since those hormone levels are changing rapidly at this time) and into adulthood.
Non-genetic Parenting (adoption and egg donation, etc.)
How does parenting differ for mothers who had different paths to motherhood, including in vitro fertilization (IVF) and egg donation? A study found that mothers who conceived their child through egg donation or IVF actually reported being more satisfied as a parent than mothers who had children conceived naturally. I think this makes sense as these moms had to go through many struggles to be able to conceive their child and were likely highly invested in parenting. Both IVF and egg donation moms rated their parenting as warm and joyful and their children as happy and low in anger. When actually observing how these moms parent their children, researchers found that moms who conceived their child by IVF were actually more sensitive than moms whose child was conceived via egg donation. Their children were also rated as more responsive and involved. This might indicate that being genetically related to your child might be helpful in the mother-child relationship. HOWEVER, both IVF and egg donation moms overall were high quality parents, so the effects are pretty small.
Adolescents who were adopted report that they don't think their lack of a genetic link with their adoptive parent has any effect on their relationship with them! I think this is great news for families formed through adoption.
A study showed that boys show more aggression than girls when playing with a doll that they had previously seen being hit by another person. Boys were also more aggressive when they were engaging in pretend play. Teachers tended to rate boys as more aggressive than girls. However, the only kind of play that predicted whether a teacher rated the child as aggressive was playing aggressively with the doll that had been hit. Neither positive nor negative pretend play predicted whether their teacher rated them as aggressive in the classroom. So in order to see whether a child might be aggressive in a classroom, seeing how children act during the aggressive doll task might be a good way to find out.
Children with different types of diagnoses have different types of play. Children with autism spectrum disorder (ASD) and specific language impairments (SLI) both have play with less imagination, organization, and complexity than typically developing children, but they do not differ in the emotions they display during play. Children with attention deficit hyperactivity disorder (ADHD) and typically developing children tend to have more aggressive play than children with ASD or SLI. Children with ASD are usually the most passive during play, while children with ADHD are typically the most impulsive and hyperactive and pay the least attention (which makes sense given their diagnosis!).
How sensitive are you to your surroundings?
There is growing evidence that some people are more sensitive to the environment than others and how sensitive they are to the environment predicts how they do later in life. For example, let's imagine there are two children. One is very sensitive to the environment, while the other is not really that sensitive to the things going on around her. Let's call the sensitive child "Orchid" (because orchids are very sensitive to their surroundings), and let's call the less sensitive child "Dandelion"(because dandelions are very hardy in a number of environments). In a really bad environment, like growing up in extreme poverty, Orchid is more likely to have a bad outcome, like poor mental or physical health, because she's very sensitive to her environment. On the other hand, Dandelion might do OK in that environment--not great but not terrible--because she is less sensitive to the environment. In a really good environment, like having a stable family income and very sensitive parents, Orchid is more likely to have really great outcomes because she's sensitive to all the good things happening around her. Dandelion is likely to do OK in this environment, too, but not as great as Orchid since she's less sensitive to the good things in her environment. Interesting, right? I also learned that our genes are partly responsible for who is more sensitive to the environment.
Child Maltreatment & Parenting
I attended a few talks about the "intergenerational transmission of maltreatment," which basically asks why some parents who were maltreated when they were children go on to maltreat their own children, and why many don't. Of all types of abuse (physical, sexual, emotional, neglect), researchers reported that parents who were emotionally abused by their own parents (e.g., belittling, scaring, manipulating their child) were the most likely to emotionally abuse their own children. Parents who were neglected as children were the least likely to neglect their own children. Parents who experienced multiple types of abuse (physical, emotional, sexual) were the most likely to go on to abuse their own children (except for parents who experienced neglect), which was termed the "spillover effect." Parents who were abused as children were more likely to be less sensitive and warm to their own children, so early abuse may affect one's own parenting.
When we study the effects of stress on children, one option is to take a disease-centered approach, which means that you select children that already have a specific chronic disease and you examine how stress affects their symptoms. For example, some people study children with asthma, and they find that greater family stress makes asthma symptoms worse for these children!
One researcher reported that civic engagement (e.g., voting, activism, becoming involved in politics) was related to lower depressive symptoms and fewer risky behaviors in adulthood, but civic engagement did not affect physical health. In addition, adolescents who were engaged in political activism were more likely to do well financially and move up the socioeconomic ladder as adults than those who were less involved in activism. Interesting food for thought!
My Science at SRCD
I presented some science, too! Don't worry about not being able to read the poster above. I just wanted to give you an example of what a poster for a scientific conference looks like!
My first poster (pictured above) asked the question: How does iron deficiency during the first 18 months of life affect our emotions and behaviors into adolescence?
My research team at Michigan has been following the same people (over 1000 of them!) in Chile for nearly 25 years, so we can figure out a lot about how these individuals develop over time. I wanted to know how having iron deficiency--the most common nutrient deficiency in the world--affects emotions and behavior over time and whether it affects boys and girls differently. Since iron deficiency is present in around 10-20% of infants in developed countries and 30-80% of infants in developing countries, and it leads to negative effects on IQ, emotion, and social behavior, it's a huge global health problem!
I found that for girls, iron deficiency during the first 18 months of life was related to more symptoms of anxiety and depression when children were 5 and 10 years old, but iron deficiency didn't really predict problems into adolescence. For boys, it was a different story. Iron deficiency in the first 18 months of life was related to more externalizing problems (e.g., breaking rules, being aggressive) for 5 year olds. Iron deficiency then predicted more externalizing problems and anxiety and depression symptoms at 10 years of age, and it predicted more externalizing problems, anxiety and depression symptoms, AND social problems in adolescence! So overall, it seems that boys are more sensitive to the effects of iron deficiency on emotions and behavior.
My second poster (not pictured) asked whether children and adolescents with more depressive symptoms had greater cortisol (a hormone that helps our body respond to stress) responses to a stressful task and whether boys and girls produced different levels of cortisol. If we know how whether cortisol levels can predict who develops depression, we can target children early and get them help so they don't develop depression!
I found that girls with higher depressive symptoms produced the highest amounts of cortisol during a stressful task (a public speech -- eek!), while boys with higher depressive symptoms didn't really produce any extra cortisol to respond to the stressful task. This information will help us to understand who is at risk for depression and we can see if reducing depressive symptoms makes their cortisol production more normal. We can also investigate why cortisol is related to depressive symptoms since it might give us a clue as to what's going on in the brain to put certain people at risk for depression!
March for Science!
I was so happy to participate in the March for Science in Ann Arbor! There was an awesome turnout, very clever signs, and great support for science and evidence-based policy. As a scientist, it's frustrating to see when people ignore science and reject information that is against how they already view the world. It's a very human response, and we all do it to a certain extent, but I think it really holds us back. We can all benefit so much from being open to new information and being curious about how the world works. Some of our greatest discoveries happen when we find out that things don't actually work the way we thought they did. AFTER we use science to figure out how things really work, we can use everything we learn to come up with the best solutions to the world's most pressing problems. Creating policies without any evidence that they work is a waste of our time and money. Just another reason we need science!
I hope you had a great Earth Day and have a week filled with discovery!