Components of the Human Connectome Project
An important objective of the Human Connectome Project is to understand the relationships among functionally distinct regions or parcels of the human brain. While anatomic relationships should remain relatively stable over time, functional relationships may change.
Why is Task MEG useful?
As with task-evoked fMRI we are using MEG/EEG to examine brain regions whose activity changes when people are asked to (i) process different kinds of information; (ii) use different types of thinking skills; or (iii) respond in different ways. Task-evoked MEG/EEG provides a more directed measure of brain activity than fMRI and can be measured much more quickly. Changes in brain activity while individuals perform a variety of different tasks can be recorded hundreds of times each second. This rich temporal information can shed light on directionality and timing of information flow among brain regions. We can use the information about which brain regions activate during which tasks to help understand how the brain is organized.
How will we use the task MEG?
Task-related MEG analyses will help us identify and characterize the interactions among functionally distinct nodes in the human brain. In turn, this will help us guide, validate, and interpret the results of the connectivity analyses obtained using resting state fMRI and HARDI diffusion imaging. We are developing and utilizing a core battery of tasks that each participant will perform. These tasks are being selected and developed so that we can identify the location of nodes both in a group of participants, and in individual participants. We will do this for as many different neural systems as it is feasible to assess within the time that we have available to scan each participant.
We are utilizing a subset of the tasks defined for fMRI to allow analyses of the flow of information among the nodes identified in key networks at a much finer timescale than possible with BOLD fMRI (see Task fMRI).
How will we measure behavior?
Click on the following link for a description of candidate paradigms for task MEG and fMRI. In phase 1, we are piloting these paradigms to determine which ones show robust and reliable activation within individual participants. After these pilot studies, we will decide how many paradigms it is feasible to use with each participant given the time that we will have available to scan each person.