Investigating the role of the right inferior frontal gyrus in control perception: A double-blind cross-over study using ultrasonic neuromodulation
André Forster, Johannes Rodrigues, Philipp Ziebell, Joseph L. Sanguinetti, John JB. Allen, Johannes Hewig
Neuropsychologia 2023 · 10.1016/j.neuropsychologia.2023.108589
Abstract
Being able to control inner and environmental states is a basic need of living creatures. The perception of such control is based on the perceived ratio of outcome probabilities given the presence and the absence of agentic behavior. If an organism believes that options exist to change the probability of a given outcome, control perception (CP) may emerge. Nonetheless, regarding this model, not much is known about how the brain processes CP from this information. This study uses low-intensity transcranial focused ultrasound neuromodulation in a randomized-controlled double blind cross-over design to investigate the impact of the right inferior frontal gyrus of the lateral prefrontal cortex (lPFC) on this process. 39 healthy participants visited the laboratory twice (once in a sham, once in a neuromodulation condition) and rated their control perception regarding a classical control illusion task. EEG alpha and theta power density were analyzed in a hierarchical single trial-based mixed modeling approach. Results indicate that the litFUS neuromodulation changed the processing of stimulus probability without changing CP. Furthermore, neuromodulation of the right lPFC was found to modulate mid-frontal theta by altering its relationship with self-reported effort and worrying. While these data indicate lateral prefrontal sensitivity to stimulus probability, no evidence emerged for the dependency of CP on this processing.
Abstract via europepmc.
Exposures
Exposure 1: litFUS to right IFG (F8)
Target: inferior frontal gyrus — “right inferior frontal gyrus of the lateral prefrontal cortex, F8 electrode position”
Device: other named manufacturer · Thync ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 500 | ✓✓✓ |
| Pulse duration (ms) | not reportedimplied by duty cycle ÷ PRF: 0.125 ms (not stated by the paper) | ⚑ |
| Pulse repetition frequency (Hz) | 40 | ✓✓✓ |
| Duty cycle (%) | 0.5 | ✓✓✓ |
| Sonication duration (s) | 120 | ✓✓✓ |
| 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 |
120 s of litFUS at F8 with 0.5% duty cycle and 40 Hz PRF, applied about 40 min before the EEG task; sham was the same device pointed away from the scalp.
Flags from extraction
n_subjects— 41 volunteers were investigated; 39 data sets analysed (one took part in one session, one had data-collection problems). Enrolled recorded.exposures[0].unspecified_domain.ispta_w_cm2— Paper gives 'an acoustic power of 199 mW/cm2' and MI 1.53 without naming the intensity metric or domain; left empty.exposures[0].timing.pulse_duration_ms— Pulse duration not stated.sham_type— Sham: device pointed in the opposite direction, away from the scalp, with the device still emitting.exposures[0].device.model— Device described only as a manufactured device (Thync).