Here is an interesting thought to ponder. What is your brain doing when you are not doing anything or performing a mindless task, like when you let your mind wander while listening to a monotonous lecture or are sitting in traffic? Interestingly, even when you are not focusing on a task, the brain is constantly active. Neurons across multiple regions of the brain are continually firing even when you are not involved in a particular activity.
We know this for a fact because scientists have studied blood supply to active brain areas by using functional MRI (fMRI). When you are not focused on a task, there are large areas of the brain that become active and have increased blood flow. These active regions of the brain start talking to each other as networks and are called the resting state networks.
These resting state networks are involved in a wide variety of thoughts and mental activities. Some of the functions attributed to these networks include self-reflection, reminiscing past events, imagining the future, and social judgements. Studying resting state networks is extremely exciting because these networks can become altered by disease. Researchers have discovered changes in these resting state networks in a host of disorders such as autism, depression and chronic pain.
Image: (Images 1 and 2) Images of the brain with blobs of color showing the regions of the brain that form one of the resting state networks called the default mode network. This network is the most widely studied of the resting state networks. (Images contributed by Tom Maloney, APPLICATION SPEC II, Neuroimaging Research Consortium)
Currently, evaluation of these resting state networks by resting state functional MRI is still in the realm of research. If you or your child has a clinical functional brain MRI, this will not involve a resting state functional MRI.
Related article: What is Functional MRI? Our Expert Explains
At Cincinnati Children’s, radiologists and imaging research scientists in the Department of Radiology work hard to understand brain function in multiple brain disorders by studying changes in resting state networks. The process of obtaining a resting state functional MRI is just like getting an MRI of the brain. The MR scanner acquires a special sequence of images of the brain while the participant is instructed to not focus on any thought and let their mind wander. A large amount of time is spent to process the obtained images to gather meaningful results. Improved understanding of the disruptions in these resting state networks holds great promise in changing the outcome of multiple diseases.
Contributed by Dr. Rupa Radhakrishnan and edited by Glenn Miñano, BFA.