Table 1. Ultrasonic stimulation parameters.
| Exp. | f(kHz) | depth (mm) | PD(ms) | PRF(kHz) | DC | PTD(ms) | Isppa(W/cm2) | P(Mpa) | MItc |
|---|---|---|---|---|---|---|---|---|---|
| I | 500 | 35 | 0.3 | 1000 | 30% | 100/500 | 32.5/65 | 1.02/1.44 | 0.99/1.40 |
| II | 250 | 28 | 0.3 | 1000 | 30% | 500 | 6.35/19.06 | 0.45/0.78 | 0.65/1.12 |
| III | 500 | 30 | 0.1 | 1000 | 10% | 500 | 9.26 | 0.54 | 0.53 |
| IV | 250 | 50* | 0.3 | 1000 | 30% | 400 | 4.34/8.69/10.52 | 0.37/0.53/0.58 | 0.53/0.76/0.83 |
f = fundamental frequency, depth = TPO focus setting for distance of free-water full-width half-maximum from transducer exit plane, PD = pulse duration, PRF = pulse repetition frequency, DC = duty cycle, PTD = pulse train duration, Isppa = spatial-peak pulse-average intensity in free-water, P = pressure, MItc = transcranial derated mechanical index. The ramp shape for all experiments was rectangular. For estimated intracranial indices for Experiments I & II see Appendix 5—figure 5.
*
Note: Experiments I-III targeted the hand motor area. Experiment IV targeted the corticospinal white matter.