Calibration WG Projects published QA Analysis Friedman L; Glover GH. Report on a multicenter fMRI quality assurance protocol. JMRI 23: (2006). Smoothness equalization Friedman L; Glover GH; Kranz D; Magnotta V; FIRST BIRN. Reducing Scanner-to-Scanner Variability of Activation in a Multi-center fMRI Study: Role of Smoothness Equalization. NeuroImage 32: (2006).

Calibration WG Projects published BH Thomason ME; Burrows BE; Gabrieli JDE; Glover GH. Breath holding reveals differences in fMRI BOLD signal in children and adults. NeuroImage 25: (2005). Thomason ME; Foland LC; Glover GH. Calibration of BOLD fMRI using Breath-holding reduces group variance during a cognitive task. Human Brain Mapping (Epub May 2006).

Calibration WG Projects eliminated SM None of the areas were deemed reliable, esp. for Sz.

Calibration WG Projects underway Perfusion measurement BH calib Coil comparison- Multichannel vs. single channel

Calibration WG Projects underway Perfusion measurement BH calib Coil comparison- Multichannel vs. single channel

No calib BH Calibration: Individual Subs Calib 5 ≤ t ≤ 20 M. Thomason et al. 2006

No calCalib 3.5 ≤ t ≤ 10 vol = p.001vol = 1.0 BH Calibration: Group Activation M. Thomason et al. 2006

Calibration: SWM 5 subjects, parietal M. Thomason et al. 2006

Control of Inspiration

no control BOLD Results w/control

Residuals across 8 trials * (p=0.006) * (p=0.005) N = 10 subs

const cntl no cntl Single Subject

SM BOLD response in normals: BH & SM BH Red: 4 non-smokers Blue: 4 smokers

Calibration WG Projects underway Perfusion measurement BH calib Coil comparison- Multichannel vs. single channel

Ratio 8/1 STAN SUB > 2.5-> ALL SCALES START AT 0.0 SFNR – CP COIL SFNR – 8-CHANNEL COIL COMPARING COILS ON SFNR UCIR SUB1 UCIR SUB2 MINN SUB1

Ratio 8/1 YALE SUB1YALE SUB > 2.5-> ALL SCALES START AT 0.0 SFNR – CP COIL SFNR – 8-CHANNEL COIL COMPARING COILS ON SFNR YALE SUB3

Unsmoothed Ratio 8/1 YALE SUB1YALE SUB2 2.5-> ALL SCALES START AT 0.0 COMPARING COILS ON SFNR YALE SUB3 Smoothed 10 mm FWHM Ratio 8/1 2.5->

Conclusions from Resting State Analyses 8 channel coil has less percent noise than 1 channel coil when unsmoothed Smoothing dramatically reduced noise Smoothing equalizes noise of the two coils to a remarkable extent Little to no advantage to multichannel coils in SFNR or Percent Noise when data smoothed to conventional levels (FWHM = 7 – 10)

Auditory Oddball Data 3 subjects 2 tasks/per study: –Auditory Oddball (4 runs, 143 TRs, 286 sec) FBIRN Phase II sequence, no PACE, ascending acquisition, TR=2.0, 64x64 matrix, no apodization filter.

Percent Signal Change Left Motor Cortex Left BA 40 Ant. Cingulate Left BA 22 Left BA 41 Right BA 47 Right CB Multi Single

1 Channel Coil8 Channel Coil T-value maps: t-values are for the 3-6 second time point  T=0.0  T=3.9, p < threshold T=2.81 p <0.005

Preliminary Conclusion Some evidence for a Superior-to-inferior gradient in the relationship between the coils. At superior levels (left motor cortex, left BA 40) both Percent Signal Change and CNR (t-values) are elevated in the 8 channel coil At inferior level (right cerebellum, BA47), single channel coil is stronger both for Percent Signal Change and CNR. At intermediate levels, the coils appear to perform similarly.

Thoughts on Why The Answer is Probably Hematocrit Smoking Increases Hematocrit Hemocrit declines with age. Hypothesis: Although both BOLD and BH depend on Hematocrit, BH dependence is much stronger, leading to increased BH response in smokers