1. Calibration Working Group Progress visual stimulus calibration data smoothness effects on analysis Proposed tasks for competing renewal

2. fBIRN Visual Stimulus How uniform is stimulus luminance across sites? Does luminance matter to SM or other tasks?

3. fBIRN Visual Stimulus Developed brightness/solid angle measurement technique - commercial photometer (Sekonic) for each site - develop Eprime script (Lee Friedman) with 1. graduated scale of 5 flat-field intensities from 0 to 100% 2. solid angle measurement grid - protocol for usage All sites made measurements

4. fBIRN Visual Stimulus Raw dataBrightness

5. fBIRN Visual Stimulus Results: Two sites deemed too bright Remediation: Adjust projector settings Neutral density filters Does luminance matter? Stanford and NM performed SM scans with different intensities

6. SM task, visual only. 1.5T TE/TR/FA 40/1000/70 14 slices 4.0/0.5mm 22 cm FOV, 20s/off/on, 200 s scan (200 frames) Stanford, 7/20/04 Cal. Lux 1194 640 226 45

7. fBIRN Visual Stimulus

8. Conclusions of luminance studies fMRI studies demonstrated only small influence of luminance on activation in visual cortex in SM task Intersite differences in visual presentation systems reduced to avoid psychophysical discomfort

9. Effects of Image Smoothness Does image smoothness vary between sites? Does smoothness effect fMRI sensitivity? Can we correct for site differences in smoothness?

10. Novel Tones – Effect Size Maps UNSMOOTHED SMOOTHED HARVMINNIOWANMEX.200 -.200 -.075.075 Slide provided by Lee Friedman, Ph.D.

11. CWG Renewal Aim 1: Develop functional phantom for objective calibration Obtain smoothness measurements to normalize reconstruction apodization Refine phantom in collaboration with vendor Acquire sensitivity data for each site with phantom and volunteers to validate use of phantom Develop calibration method

12. Aim 1: Develop functional phantom for objective calibration Uses MRI Devices “SmartPhantom” Prelim results for grant: MRI-D brought phantom to Stanford for evaluation Glover and Friedman made measurements Conclusions: concept should work for fBIRN more development needed on phantom fBIRN will obtain 3 systems that will span 1.5T-4T Aim 1

13. “SmartPhantom” - based on B1 modulation using tuned circuit - 4 bit control of contrast 4-step block trial timeseries (40 s on/off blocks)

14. CWG Renewal Aim 2: Study use of HRF for calibration Optimize HRF task design using SM and WM tasks Examine subject-specific HRFs Develop calibration method

15. Aim 2 FHRF method: linear Second order

16. Aim 2: HRF Method Activation maps: Canonical HRF Second order HRF First order HRF

17. CWG Renewal Aim 3: Develop perfusion methods select technique, develop sequences for platforms optimize acquisition parameters measure baseline rCBF in 10 controls and pts. implement in fBIRN

18. Aim 3: ASL Methods QUIPSS IIModeling of HRF

19. CWG Renewal Aim 4: Develop BH calibration for longitudinal studies implement BH, including respiratory/cardiac monitoring acquire longitudinal scan data using SM and BH implement in fBIRN

20. Aim 4: BH Methods Influence of BH performance on activation Calibration of BH to measure HRF using measured respiration waveform