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1. FSFAST Tutorial Data Description

The functional data were collected as part of the Functional Biomedical Research Network (fBIRN, www.nbirn.net).

• Working-memory paradigm with distractors
• 18 subjects
• Each subject has 1 run (except sess01 which has 4 runs)
• Collected at MGH Bay 4 (3T Siemens)

• FreeSurfer anatomical analyses

2. Functional Paradigm

The paradigm was designed to study the effects of emotional stimuli on the ability to recall items stored in working memory.

• Blocked design
• Each block consisted of 3 phases
  1. Encode (16 sec) - 8 stick figures to remember (no response)
  2. Distractor (16 sec) - 8 distractor images (response whether there is a face in the image)
     1. Emotional - Distractors are emotionally disturbing
     2. Neutral - Distractors are emotionally neutral
  3. Probe (16 sec) - 8 pairs of stick figures. Subject responds as to which of the pair was in the original Encode.
• Between each block was a 16 sec scrambled image used as baseline.

The above yields 5 conditions:

1. Encode
2. Emotional Distractor
3. Neutral Distractor
4. Probe following Emotional Distractor
5. Probe following Neutral Distractor

The scrambled image will be modeled as a baseline, not as a condition.

3. Functional Data

• Original data: each subject had 8 runs
• This data: each subject has 1 run (except for sess01 who has 4)
• Each run lasts 142 time points
• TR = 2 sec.
• There is one run of rest data for 13 subjects
• There is a B0 map for each subject

4. Anatomical Data

• FreeSurfer analysis has been run for all 18 subjects

5. Getting the Data (not necessary for FreeSurfer April 2011 Course)

You can get the analyzed functional data (10G) from:

wget ftp://surfer.nmr.mgh.harvard.edu/pub/data/fsfast-functional.tar.gz

You can get the structural data (5G) from:

wget ftp://surfer.nmr.mgh.harvard.edu/pub/data/fsfast-tutorial.subjects.tar.gz

6. Organizing the Tutorial (not necessary for FreeSurfer April 2011 Course)

cd to a place on your network where you have enough space to unpack the tutorial data.

cd /place/with/space

Untar the data

tar xvfz fsfast-tutorial.tar.gz
tar xvfz fsfast-tutorial.subjects.tar.gz

You will need to set the TUTORIAL_DATA environment variable. In tcsh or csh

setenv TUTORIAL_DATA /place/with/space 

You will also need to link the FreeSurfer anatomical subjeccts (data in fsfast-tutorial.subjects) into your $SUBJECTS_DIR.

You should set the FSFAST output format to be compressed NIFTI (nii.gz):

setenv FSF_OUTPUT_FORMAT nii.gz

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