Updated: Feb 25, 2021
#freshfromthelab. Maheen Siddiqui on mitochondrial activity and autism.
Maheen is a final year PhD student who has recently submitted her thesis for review.
Not only is Maheen eagerly awaiting her viva - the oral examination, which once she passes means will be able to proudly stick those two all-important letters (Dr) at the beginning of her name - she is also expecting her first child in a few months.
As part of her project, this soon to be yummy (super high-tech) mummy has taken innovation to the next level by collaborating with a variety of experts to conduct the first-ever non-invasive measurement of mitochondrial activity in awake healthy infants to infer brain activity.
So hold on to your hat – this one’s going to be techy!
Remember those EEG “blips” we talked about a few blog posts back ? Well, these “blips” are the results of tiny electrical currents that occur when brain cells called neurons send messages to one another. And just like a thermometer measures temperature, EEG measures this naturally occurring electrical activity and tells us when it is occurring.
But this only tells us half the story. With EEG, we cannot tell exactly what part of the brain is active. This is important because different parts of the brain are better at different things. For example, the back of our brain is an expert at processing visual information about our world, but not so good at understanding what we hear. Near-infrared spectroscopy, on the other hand, is much better at getting into the nitty-gritty of what areas in the brain are active.
“Near-infrared spect-what-scopy?” I hear you say!
Near-infrared spectroscopy, or NIRS for short, is a non-invasive technique perfect for studying infant brains. It works by shining harmless infrared light through the scalp and then detecting how much light has been absorbed by brain tissue. Different components that make up the body absorb different amounts of light. You can see this in action if you shine a torch light through our fingertips, notice that you can see your veins as slightly darker than the rest of your fingers. That is because they are absorbing more light. By measuring how different components of the brain are absorbing light we can deduce how they are working.
Just like any other organ in the body, whenever we use our brain – be that for thinking about what we are having for dinner or chatting on the phone with a pal – it needs energy. Inside every cell, including neurons, energy is produced by mitochondria. Now, for some of you, the word “mitochondria” may be generating a flashback to a sweaty-palmed teenaged you sitting their GCSE biology exam - but stick with me as these fascinating powerhouses might just hold the key for better understanding how babies’ brains grow and learn about the world. Now the clever thing here is, using NIRs we can determine mitochondrial activity by monitoring how much light it absorbs as its going about it’s business making energy, and this allows us to deduce how active the brain is but more importantly where this activity is occurring.
This technique is completely harmless and is relatively practical as all it involves is popping a special hat on the infant in question’s head – although, trying to get my 7-month-old nephew to wear a hat and then sit quietly for 20 minutes is not my description of a fun Monday morning. But nevertheless, Maheen persuaded (with an armoury of bubbles, nursery rhymes and flashy toys) over 40 infants to do just that and got some quite interesting results.
Taking her 40+ four- to seven-month olds, Maheen was able to show that using NIRs to measure mitochondria activity is in fact a valid method of measuring baby brain activity. Now remember I told you just a moment ago that different areas of the brain do different things? Well, the part of the brain that is just above and behind our ear (called the temporal lobe) plays a big role in processing social information. When the infants were shown social videos of women singing nursery rhymes, the amount of light absorbed by the mitochondria in the temporal lobe changed, indicating that it was using more energy, therefore showing the brain actively processing these social videos.
But…So what? Why has Maheen been fiddling about with infrared light and mitochondria for the past 4 years?
The technique Maheen has helped to develop during her PhD is super unique in the way that it is not only usable with babies, but it also measures something that we haven’t yet been able to measure before about how the baby's brain develops, and about how the average brain continues to function throughout different life stages. One domain it is particularly relevant for research into autism, as mitochondria dysfunction is a biological feature of this disorder. Using NIRs to measure mitochondrial activity we can understand its contribution to autism, even before behavioural symptoms of autism arise. In other words, we might be able to "spot" autism even before the behaviour of the babies gives us clues about this. And this, as we have discussed previously, will enable us to offer children at risk the best possible environment to fulfil their own unique potential.
PS: We are so excited that Maheen is on board with It All Starts In the Womb and that she is going to be our guest at the BabyBrains Workshop coming up this Thursday and Friday!!