Sam epi

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Description

The sam_epi routine is a program designed for detecting sub-threshold epileptiform activity in the brain. It evaluates each voxel time series to determine kurtosis. The recommended pipeline is to run sam_cov, sam_wts, and then sam_epi. The utility NIFTIPeak can then be used to identify voxels with peak or excess kurtosis values. These voxel locations can then be used as targets for a secondary run of sam_wts.

Note that datasets must be continuous, and not epoched into trials.

Usage

 sam_epi -r <dataset_name> -m <parameter_file_name> [options]

The -r flag designates the dataset name (with or without the .ds suffix), and -m designates the parameter file name.

Other options:

 -v  Verbose mode, without this flag sam_wts works silently except for error messages
 -h  Show help

Required Parameters:

 CovBand: Bandpass for the covariance matrices (and directory for weights files)
 ImageBand: Bandpass for the image
 ImageMetric: Must be KURTOSIS
 TimeInt: designates the duration for the boxcar integration
 CovType: Must be GLOBAL

Optional Parameters:

 FilterType: choose the applied filter, IIR vs. FFT 
 ImageDirectory: Directory where the output images are written, default is the SAM directory
 PrefixLength: Number of characters in the MEG dataset name used for naming MRI files

Output Files

Creates a single 3D NIFTI format image of kurtosis (g2). Output file will be named using the PrefixLength parameter.