Diagnostic ultrasound enhances, then reduces, exogenously induced brain activity of mice
Henry Tan, Devon J. Griggs, Lucas Chen, Kahte Adele Culevski, Kathryn Floerchinger, Alissa Phutirat, Gabe Koh, Nels Schimek, Pierre D. Mourad
Frontiers in Human Neuroscience 2025 · 10.3389/fnhum.2024.1509432
Abstract
Transcranially delivered diagnostic ultrasound (tDUS) applied to the human brain can modulate those brains such that they became more receptive to external stimulation relative to sham ultrasound exposure. Here, we sought to directly measure the effect of tDUS on mouse brain activity subjected to an external stimulation-a blinking light. Using electrocorticography, we observed a substantial increase in median brain activity due to tDUS plus a blinking light relative to baseline and relative to sham tDUS plus a blinking light. Subsequent brain activity decreased after cessation of tDUS but with continuation of the blinking light, though it remained above that demonstrated by mice exposed to only a blinking light. In a separate experiment, we showed that tDUS alone, without a blinking light, had no observable effect on median brain activity, but upon its cessation, brain activity decreased. These results demonstrate that simultaneous exposure to tDUS and blinking light can increase the receptivity of the visual cortex of mice exposed to that light, and that prior exposure to tDUS can reduce subsequent brain activity. In each case, these results are consistent with published data. Our results on mice echo published human results but do not directly explain them, since their test subjects received less intense diagnostic ultrasound than did our mice. Given the near ubiquity of diagnostic ultrasound systems, further progress along this line of research could one day lead to the widespread use of diagnostic ultrasound to intentionally modulate human brain function during exogenous stimulation.
Abstract via europepmc.
Exposures
Exposure 1: transcranial diagnostic ultrasound (tDUS)
Target: visual cortex, somatosensory cortex — “left visual and right somatosensory cortices”
Device: other named manufacturer · Sonosite · P21x5–1 scan head deployed by a Sonosite MicroMaxx ✓
| Waveform | not reported | |
|---|---|---|
| Fundamental frequency (kHz) | not reported | ⚑ |
| Pulse duration (ms) | not reported | |
| Pulse repetition frequency (Hz) | not reported | |
| Duty cycle (%) | not reported | |
| Sonication duration (s) | 600 | ✓✓✓⚑ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | not reported | |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | not reported | |
| In-situ pressure (kPa) | not reported | |
| In-situ Isppa (W/cm²) | not reported | |
| In-situ Ispta (W/cm²) | not reported |
tDUS delivered during Trial 2 only, a 10 min period paired (US+Light cohort) or not (US-only cohort) with a 0.1 s light flash every 10 s; ultrasound parameters are listed only in Supplementary Table S1.
Flags from extraction
n_subjects— Seven mice in the US+Light cohort and six in the US-only cohort were sonicated; the 7 Light-only mice received no ultrasound.exposures[0].fundamental_frequency_khz— All acoustic parameters are in Supplementary Table S1, not in the main text; recorded as not_reported.exposures[0].timing.sonication_duration_s— 10 min of exposure in Trial 2 is stated for the light paradigm paired with tDUS; the text does not separately state the tDUS duration.exposures[0].device.family— Sonosite is not a listed family; set to other_manufacturer.