The overall goals of our lab are to improve techniques for measuring functional brain organization (specifically, resting-state functional connectivity MRI), and to use these tools in order to understand the changes in the functional organization of the brain during childhood and adolescence. Our current research is focused on two areas:
1. Methodological improvements for resting-state functional connectivity
New developments in magnetic resonance imaging (MRI) make it possible for us to measure the amount of neuronal activity in different parts of the brain, as well as the functional connections between brain regions. This “functional connectivity” can be measured even when the subject is not actively engaged in a task (i.e., when the person is “at rest”). The technique is based on the observation that functionally related brain areas have synchronized low-frequency (< 0.1 Hz) fluctuations in neuronal activity. By looking at the correlation of low frequency fluctuations in the MRI signal between different brain regions at rest, we can get a measure of functional connectivity. However, there are many reasons why different areas of the brain could show similar fluctuations in the MRI signal. For example, two areas may show similar increases and decreases in signal due to a person’s breathing or heartbeat. The goal of our research is to identify such sources of noise and remove them from the signal, so that we can be sure that we are measuring the neuronal interaction of different brain areas. Our ultimate goal is to make it possible to reliably map the strength of functional connections in the brain of an individual person.
2. Changes in functional connectivity during childhood and adolescence
The brain undergoes marked changes in functional and structural organization during childhood and adolescence. In addition, many mental disorders begin during this developmental period. Mood and anxiety disorders, for example, show a sharp increase in prevalence during adolescence. In order to understand the causes of these mental disorders, it is important that we understand both the typical developmental trajectories of brain organization, as well as, the deviations of these trajectories in a disorder. The goal of our current research is to map the changes in resting-state functional connectivity during childhood and adolescence, using the methodological improvements described above. In one of our current research projects, we are focusing particularly on the development of brain circuitry involved in regulating emotion.