EMSE Suite Module Software
EMSE Suite SOURCE ESTIMATOR module may be used for discrete or
distributed dipole source analysis from EEG or MEG data which has been
provided by the DATA EDITOR module. Three
shell spherical models or realistic head models (using data from the
IMAGE PROCESSOR module) may be used for field
calculations. Source estimates may be output to MR
VIEWER for MRI overlay.
- Spatiotemporal dipole modeling.
Fit one or more dipoles to the data. By interacting with the data, the
operator may use up to 32 dipoles to create source models. The dipoles
are subject to a variety of user-controlled constraints (including free
or fixed locations and/or orientations, mirror pairs, and maximal power
constraints). Multiple dipole time series may be estimated using minimum
norm techniques. Confidence intervals may be estimated.
- Dipole modeling in Frequency and
Dipoles may be fit directly in the complex domain to Fourier transformed
data, permitting the estimation of generators of oscillatory activity
directly. Source Estimation using wavelets is a powerful tool for both
time and frequency domains.
such as sphere-to-plane mapping, channel group selection
(for dipole fitting), time-frequency display, Neuromag vector magnitude
display, auto-update latency changes, context menus and a modeless
dialog that lets you work while leaving the dialog open
- Seeded Dipoles. Dipole
locations may be obtained from fMRI or PET hotspots (using
MR VIEWER) and transferred to SOURCE ESTIMATOR for constrained
dipole time series analysis.
- Beamformers and other local
estimators. Local estimators reveal spatially constrained source
- Distributed source models.
Source estimates are obtained from instantaneous data samples using
maximum likelihood and Laplacian smoothing (LORETA) or covariance
statistics (PRoMS) for a set of dipole current sources fixed to a
lattice. Related options include minimum norm and MUSIC algorithm. The
resulting analysis may be viewed as a tomographic display, either for a
single time slice, or for a sequence of time slices (4D analysis)
- Cortical surface restriction*.
Distributed source estimates may be restricted to the cortical surface,
obtained from the IMAGE PROCESSOR module.
- 3 shell sphere. Digitized
electrode locations (e.g. from LOCATOR) may
be used to determine a best-fit sphere origin. Measured electrode
locations are then used to calculate field potentials.
- 1 shell sphere. External
headshape data (e.g. from LOCATOR) may be
used to determine a best-fit sphere origin for MEG source estimation. 1
shell sphere models may also be used for source analysis from ECoG data.
- Realistic headshape*. Using
segmented image data obtained from the IMAGE
PROCESSOR* module, boundary element modeling calculates field
potentials, based on skull, scalp, and brain geometry (assuming
homogeneous, isotropic compartments).
- Dynamic linkage of graphical
display windows permits selections in one window to update others
- Discrete dipole location,
orientation, and confidence intervals are represented in diagrammatic
display (3 orthogonal planes).
- Tomographic displays are
available for distributed source estimates. 6D displays optionally
include position and moment for each lattice point.
- 3D rendering and animation of cortical
surface source estimates is available through VISUALIZER.
- User Interface.
A conventional Microsoft Windows style graphical user interface is used
throughout. Dynamic linking of graphical display windows permits
selections in one window to update others automatically.
- Number of
channels. Up to a total of 256 channels (EEG and MEG) are supported
s is available through VISUALIZER.
- Graphics may
be transferred to clipboard for use by other graphics programs or for
insertion into word processors.
- Printed. User manual, including file
- On-line. User
manual and tutorial available as context sensitive hypertext.
recommended for >64 channels
||10 Mbyte for
swap space + additional data storage requirements