Integration of behavioral and physiological data with imaging data

James Voyvodic, Ph.D.

Brain Imaging and Analysis Center

Duke University

June 30, 2008

fMRI• fMRI correlates brain activity with MR image signals

• Software tools tend to focus primarily on MR image data

• fMRI attempts to control brain activity via task stimuli

• But brain activity during any task can be complexe.g. Stimulus perception, Cognitive processing, Response generation,

Autonomic responses, Homeostatic processes

• fMRI should record behavioral and physiological signals

• Image analysis tools should make use of behavioral and physiological data

NITRC Project Goals

1) Document and improve CIGAL software for dissemination (Windows OS)

What is CIGAL?

• Compilable Imaging, Graphics & Analysis Language

• Designed to be fast, flexible, and easy to use

• Single C program (CIGAL.exe) plus text files (All menus, dialogs, pre-processing, post-processing,

and real-time control programs are plain text files)

• Used in Duke PPG and FBIRN multi-site studies

• Features a real-time multi-tasking command processor

2) Develop standard, interoperable methods for integrating behavioral and imaging data

CIGAL’s real-time processor can run any number of multiple simultaneous program streams in parallel. Timing of events in each stream is automatically interleaved as necessary to ensure that every individual event occurs when specified (< ~1ms). Actual execution timing is recorded to 20 us accuracy.

Real-Time Multi-processing

Examples of multi-stream processing (A and B at different time scales).

CIGAL scripts simplify task specification

showplay 0 ; initialize new showplay tasksbackcolor = "black" ; screen background colorstextcolor = 'white‘t_r = 2000 ; scanner TRdisdaqs = 3 ; initial discarded TR’sfslscheds = { ; for creating FSL analysis files (uses stim ID #s) fixation 1 sounds 12 22 faces 13 23 movingdots 14 24}return ; ends parameter section ;Stimulus ID Flg Onset Duration LocationXY"Press for faces" 99 0 0 4000 -1 -1 ; show textfix 1 0 4000 0 -1 -1 ; central '+'tones1.wav 12 0 6000 4000face1.pcx 13 1 8000 1000 200 100dots1.avi 14 0 12000 4000 -1 -1fix 1 0 16000 2000 -1 -1tones3.wav 22 0 -1 4000face2.pcx 23 1 -1 2000 400 200dots2.avi 24 0 -1 4000 -1 -1. . .quit 0 0 300000

Sample task program:

(Stimuli are usually programmed explicitly, behavioral and physiological data acquisition is implicit and automatic)

Record multiple behavioral and physiological channels simultaneously and automatically

Multi-channel data can be integrated into analysis

- Head motion

- Accuracy- Responses

-Task conditions

- Respiration

- MR images

Storing behavioral/physiological data• CIGAL stores multiple types of data in ‘pdigm’ archive

files (includes text and binary data)– Copy of task specification file and CIGAL scripts– All software and hardware parameter settings– Real-time run log (records all important events in chron. order)– Separate record for each recorded data channel– Copy of each reformatted output file

• Archive file is self-documenting (e.g. XML header)– Variation of BIRN XCEDE metadata header

• CIGAL reformats data to accommodate analysis tools– <Events> XML format (stimulus and/or response events)– FSL “schedule” files– Performance scores– Physiological “time/value” text files

Proposal

• fMRI community via NITRC could adopt standard data formats for behavioral and physiological data

• Suggest using CIGAL’s XCEDE-like format as a model for accommodating text and binary data

• Emphasis should be on developing a library of I/O tools to facilitate standardized file formats and interoperable integration of these data in image analysis programs