We WON $1000! and more about the mobile sensors

 

 

Dear Supporters, We did it! We won $1000 for infant sleep and brain development research! Now the project is 95% funded. Feel free to share the project email or link (http://experiment.com/sleep-development) with your own community (Facebook, Twitter, etc)! Every little bit will help and the project must reach the goal in order to receive the $1000 prize. I'm certain the extra 5% ($249) will come in by the deadline, tomorrow. (Thursday, June 30th, 6pm EDT) This would not have been possible without your help, and I am eternally grateful to each of you.

I am excited and motivated to use these funds to expand the research!  Now that the campaign is almost over I'm completely focused on publication of my first "first authored" scientific paper. This paper includes the analyses of data collected, over the last three years of my PhD training, without the leg sensors, but with the 124 sensor caps, and includes 19 3.5 month olds and 19 6.5 month olds and an even distribution of boys and ­girls. This is important because even at these young ages we see sex differences in the development of the brain and behavior! We have enough participants that should allow us to compare these two groups (boys and girls) at each age. Stay tuned for future updates on our findings, and what they might mean.­­ 

In my last lab note I promised I would write more about the mobile (wireless) sensors we place on the legs, for measuring activity of the autonomic nervous system. I'm so excited to be collecting this data already, thanks to small grant from the National Science Foundation, by way of the Temporal Dynamics of Learning Center, one of five Science of Learning Centers. With two of these sensors, I’ve been able to collect some pilot data at each of 3 ages, and even some repeat measurements in the same infants at different ages. 

There's so much I could share about theses sensors, but today I’d like to focus on one of the four measures, skin conductance or electrodermal activity (EDA). This is basically a measure of condensation or sweat on the skin, but it has a very interesting connection to the brain. Most of the research that has been done with this signal has been completed with adults, while awake, in experiments to measure learning, as it relates to a fearful stimulus or picture. As you may have heard before, the amygdala is a deep brain structure that is the “emotion-center” of the brain, a region that is commonly studied with respect to fear and learning.  It seems the amygdala may be connected to more brain regions than any other part of the brain. It is a major hub, like JFK airport. It’s difficult to study this brain region in humans, unless you are using MRI, with high spatial resolution. The EEG technique we use primarily allows us to see activity in the outer regions of the brain (the cortex), but with high temporal (time) resolution. Electrodermal activity may be a window into this and other deep brain structures, including the hippocampus, which is located near the amygdala and is the most studied brain region with respect to learning and memory.  How is it that a measure from the skin could be connected to these deep brain structures? Some say that it makes sense, given that the origin of the nervous system (including the brain) and the epidermis (skin) are from the same layer of the early embryo (the ectoderm).

Another interesting aspect to keep in mind is the need to measure the signal on both legs (or both wrists/palms/feet) at the same time. It has been shown that there is lateralization with this signal, as well as in the brain, meaning that one side may be very active while the other side is not.  This might explain why many studies in the past have led to negative or no positive findings when studying EDA and the brain or behavior, as they typically measured EDA only on the non-dominant side/hand (left hand if you are right handed).  We don’t have a method, yet, to predict which side of the body might have more activity in an individual, so we need to start by measuring both sides.

Based on very minimal work in adults, using a computational method called machine learning, the EDA signal during sleep has been shown to be a better predictor of next day retention (learning and memory), than the more traditional measures of slow waves and sleep spindles, the brain activity which is the other focus of my study, and are thought to carry information from the hippocampus to the cortex. Measuring all of these signals concurrently may tell us much more about how the brain and body are processing information during sleep!  Thus, I am interested in the possible correlation of EDA during daytime infant sleep, brain activity, and behavior.

This research is important because it may open the door for another sleep based biomarker of brain development, which is more easily measured from the infant’s body, ultimately leading to the development of tools that allow us to help infants that may be at risk for developing a brain/behavior-based disorder.

Thanks again for your support! I’m looking forward to sharing results in the future!