SpmDemo - Meg Wiki

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SPM5 CBU MEG (Neuromag) Demo

The previous single-subject demo (which included GUI instructions and a batch file) is here: SpmDemoOld. However, many improvements have since been made, so we now demonstrate analysis of a group of 8 subjects with concurrent EEG data.

Introduction

This demo takes MEG, EEG and MRI data from 8 subjects from the raw data to final group-level statistics in a template (MNI) space of differences between conditions in source strength during a time-frequency window of interest. The data were recorded at the CBU on our Neuromag MEG and Trio MRI machines, and are picked up directly from our /megdata/cbu/... and /mridata/cbu... network directories (as FIFF and DICOM formats respectively. For users outside the CBU, please email RikHenson for access to the raw data.

The subjects saw 172 trials of either faces or scrambled faces (the same paradigm used in fMRI, EEG and MEG by Henson et al, 2003, Cerebral Cortex; 2007, Neuroimage; in press, Neuroimage). Greater evoked energy for faces than scrambled faces is expected around 170ms (M170) from sources in bilateral fusiform and possibly right lateral temporal regions.

The demo is designed to illustrate some key unique advantages of SPM, eg use of SensorSpm to localise condition effects in (a 2D sensor) space and in time, data fusion (simultaneous inversion of MEG and EEG data) and group inversion. It generally follows this pipeline: BasicMeegPipelineSpm5

Notes on batch script

At the moment, we provide just a linear Matlab batch script - there are no accompanying GUI instructions yet (eg if you prefer pressing lots of buttons). Though the batch script does require some basic knowledge of Matlab (eg, arrays, cell arrays and simple "for..." and "if..." statements), we strongly recommend batching, for example if you have many subjects, want to keep a record of what you have done, or ever want to re-run with a new parameter/modification. In the future, we expect batching will be made easier (and more modular) by using AA http://imaging.mrc-cbu.cam.ac.uk/imaging/AutomaticAnalysisIntroduction

To run the script below, you simply need to download it to someone on your Matlab path, create a new directory (eg '/imaging/me01/CBU_SPM_MEG_Demo', and replace the line near the start of your version of the script with wd = '/imaging/me01/CBU_SPM_MEG_Demo'. The type 'spm 5 eeg' at the Linux prompt, and in the new Matlab window, type the name of the script (or open the script in an Editor, and run it bit by bit by cutting and pasting or using the Matlab JVM debugger).

Ok, no more waffle: here it is attachment:cbu_meeg_spm5_pipeline.m