Transcranial ultrasound stimulation of the medial frontal cortex transiently improves performance by modulating conflict monitoring dynamics
Camila S. Agostino, Hans Kirschner, Daniel Janko, Eleonora Carpino, Lennart Verhagen, Markus Ullsperger
2026 · 10.64898/2026.08.06.743260
Abstract
Conflict monitoring and error processing are fundamental mechanisms underlying cognitive control and adaptive behavior and have been consistently associated with increased activity in the anterior midcingulate cortex (aMCC). Here, we used transcranial ultrasound stimulation (TUS), an emerging technique that enables non-invasive, deep, and focal neuromodulation, and EEG to investigate the causal role of the aMCC in cognitive control. Our findings demonstrate that TUS of aMCC improved performance, modulated the relationship between conflict monitoring and the stimulus-locked N2, and strengthened the suppression of distracting flankers as revealed by drift-diffusion model analyses. This suggests that TUS of aMCC enhances proactive control. Interestingly, TUS did not affect the error-related negativity as a measure of error monitoring. Finally, the TUS effects were observed during early compared with later task blocks corroborating previous findings which suggested that TUS effects are temporally dynamic and characterized by a limited post-stimulation window. HIGHLIGHTS aMCC-TUS and PCC-TUS both increase behavioral accuracy during the early stages of task performance. aMCC-TUS transiently reduces the effect of incongruence on the stimulus-locked N2 suggesting reduced response conflict. Exploratory DDM analyses suggest that aMCC-TUS improves suppression of conflict- inducing distractors. aMCC thus selectively enhances proactive control, thereby reducing response conflict. TUS effects show a transient temporal profile, peaking 17–27 minutes after stimulation and declining after ∼37 minutes.
Abstract via europepmc.
Exposures
Exposure 1: aMCC TUS
Target: cingulate cortex — “anterior midcingulate cortex (aMCC)”
Device: NeuroFUS · Sonic Concepts (sold by Brainbox) · NeuroFUS PRO with CTX-250-32 transducer ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 250 | ✓✓✓ |
| Pulse duration (ms) | 20 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 5 | ✓✓✓⚑ |
| Duty cycle (%) | not reportedpulse duration × PRF gives 10% | ⚑ |
| Sonication duration (s) | 120 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | 30 | ✓✓✓ |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | simulationmean or range across subjects | |
| In-situ pressure (kPa) | 452.8, 487.9swept | ✓✓✓ |
| In-situ Isppa (W/cm²) | 7.01, 8.05swept | ✓✓✓⚑ |
| In-situ Ispta (W/cm²) | 1.04, 1.2swept | ✓✓✓ |
5 Hz rTUS protocol: pulse length 20 ms (plus 10 ms Tukey ramping), pulse repetition period 200 ms, total duration 120 s, delivered once per session before the EEG flanker task (about 17 min later); sham was the same protocol for 2 s over aMCC.
Exposure 2: PCC TUS (active control)
Target: posterior cingulate cortex — “posterior cingulate cortex (PCC)”
Device: NeuroFUS · Sonic Concepts (sold by Brainbox) · NeuroFUS PRO with CTX-250-32 transducer ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 250 | ✓✓✓ |
| Pulse duration (ms) | 20 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 5 | ✓✓✓ |
| Duty cycle (%) | not reportedpulse duration × PRF gives 10% | |
| Sonication duration (s) | 120 | ✓✓✓ |
| Free-field pressure (kPa) | not reported | |
|---|---|---|
| Free-field Isppa (W/cm²) | 30 | ✓✓✓ |
| Free-field Ispta (W/cm²) | not reported | |
| In-situ estimate | simulationmean or range across subjects | |
| In-situ pressure (kPa) | 468.4, 476.2swept | ✓✓✓ |
| In-situ Isppa (W/cm²) | 7.5, 7.68swept | ✓✓✓ |
| In-situ Ispta (W/cm²) | 1.36, 1.39swept | ✓✓✓ |
5 Hz rTUS protocol: pulse length 20 ms (plus 10 ms Tukey ramping), pulse repetition period 200 ms, total duration 120 s, delivered once per session before the EEG flanker task (about 17 min later); sham was the same protocol for 2 s over aMCC.
Flags from extraction
exposures[0].in_situ.isppa_w_cm2— 7.56 W/cm2 is an average across all stimulation conditions (aMCC and PCC, both hemispheres) from simulation; Table 1 lists per-target values, some under 'Ipa' and 'Isppa' rows that disagree, so the pooled text value is used for both exposures.exposures[0].timing.pulse_repetition_frequency_hz— From '5Hz rTUS protocol' and 200 ms pulse repetition period.exposures[0].timing.duty_cycle_pct— Not stated; not computed.sham_type— Sham was 2 s of the same protocol aimed at aMCC (minimal dose), so it is real output; PCC is an active control site.auditory_control— Sham of 2 s was delivered so participants experienced the auditory confound similarly to verum; coded as matched_device_sound.randomised— Order of sessions not described.