Table 2.
Percent signal change, noise level, the number of activated voxels, and t-value in block-designed S1 and OB fMRI obtained with the GRE sequencea.
| Area | Sampling pattern | Percent change | Noise level | # of active voxels | t-value | ||
|---|---|---|---|---|---|---|---|
| Positive only | Positive + Negative | ||||||
| S1 | Full | 6.5±2.2% | 5.4±0.4% | 51±13 | 69±17 | 4.8±1.0 | |
| R=2 | Gaussian | 4.1±1.3% | 5.1±0.5% | 53±11 | 80±43 | 5.1±0.8 | |
| Rand+C6 | 3.3±1.2% | 5.0±0.3% | 59±8 | 90±32 | 5.1±0.5 | ||
| R=4 | Gaussian | 2.2±0.5% | 3.8±0.4% | 50±11 | 95±28 | 5.4±0.6 | |
| Rand+C6 | 2.1±0.6% | 4.1±0.4% | 77±18 | 117±33 | 5.6±0.6 | ||
| OB | Full | −4.2±0.5% | 14.5±2.8% | 1433±351 | 1519±370 | 3.1±0.2 | |
| R=4 | Gaussian | −3.6±0.3% | 10.3±1.4% | 3985±489 | 4442±71 | 3.9±0.3 | |
| Rand+C6 | −4.1±0.4% | 9.8±2.4% | 5113±717 | 5451±751 | 4.9±0.8 | ||
Percent change, noise level, and t-value were obtained from the ROI, while # of activated voxels were calculated from entire images. “Positive only” and “Positive+Negative” refer to the sign of t values of the activated voxels (p<0.01). Results in S1 were first obtained from each scan and then averaged across 6 scans (n = 6). Results in OB with Rand+C6 and Full patterns were first obtained from GLM analysis of 3 concatenated scans and then averaged across different concatenated sets (n = 8). Results in OB with Gaussian sampling were first obtained from GLM analysis of 3 concatenated scans and then averaged across different concatenated sets (n = 4). The errors are standard deviations.