Creating Biomedical Technologies to Improve Health

2017 BESIP Project

MEG Core Facility
NIMH
Mentor Name: 
Richard Coppola, D.Sc.
Tom Holroyd, Ph.D.
Fred Carver, Ph.D.
Mentor Email: 
Mentor Telephone: 
(301) 402-7345

Laboratory and Project Description

Magnetoencephalography (MEG) is a non-invasive procedure similar to electroencephalography (EEG) in terms of basic principles and analysis. Subjects sit with their head inside a helmet-shaped device which contains magnetic field sensors. These superconducting quantum interference device (SQUID) sensors detect the weak magnetic fields produced by brain activity. The NIMH MEG system has 275 sensors over the head and additional reference coils for background noise elimination. Functional neuroimaging studies record the MEG while subjects perform various cognitive or manual tasks. The goal is to determine the source distribution of brain activity related to the underlying neurophysiology of cognitive and motor behavior. Under favorable conditions, spatial localization of current sources with whole head MEG is on the order of 2-3 mm at a temporal resolution better than 1 ms. Of particular interest is the understanding of the networks underlying behavior through a better understanding of the functional connectivity among brain regions both during rest and cognitive tasks. Essential to MEG studies is the complex nature of the signal processing and visualization required to analyze the recorded data. Projects in several related areas are available depending on the background and interests of interns. These include:
  • Refinement of spatio-temporal analysis using various signal processing methods
  • Mapping of MEG data onto cortical surface maps from segmented MRI data
  • Distributed source methods and development of functional connectivity methods
  • Prediction of movement from motor area activity
We utilize several existing tool packages, some are MATLAB based, but all run under Linux.