General mechanisms of task engagement in the primate frontal cortex
Jan Grohn, Nima Khalighinejad, Caroline I Jahn, Alessandro Bongioanni, Urs Schüffelgen, Jerome Sallet, Matthew F. S. Rushworth, Nils Kolling
Nature Communications 2024, 15 · 10.1038/s41467-024-49128-w
Abstract
Staying engaged is necessary to maintain goal-directed behaviors. Despite this, engagement exhibits continuous, intrinsic fluctuations. Even in experimental settings, animals, unlike most humans, repeatedly and spontaneously move between periods of complete task engagement and disengagement. We, therefore, looked at behavior in male macaques (macaca mulatta) in four tasks while recording fMRI signals. We identified consistent autocorrelation in task disengagement. This made it possible to build models capturing task-independent engagement. We identified task general patterns of neural activity linked to impending sudden task disengagement in mid-cingulate gyrus. By contrast, activity centered in perigenual anterior cingulate cortex (pgACC) was associated with maintenance of performance across tasks. Importantly, we carefully controlled for task-specific factors such as the reward history and other motivational effects, such as response vigor, in our analyses. Moreover, we showed pgACC activity had a causal link to task engagement: transcranial ultrasound stimulation of pgACC changed task engagement patterns.
Abstract via europepmc.
Exposures
Exposure 1: TUS of perigenual anterior cingulate cortex (pgACC)
Target: pregenual anterior cingulate cortex — “perigenual anterior cingulate cortex (pgACC)”
Device: Sonic Concepts · Sonic Concept, Bothell, WA, USA · H115-MR ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 250 | ✓✓✓ |
| Pulse duration (ms) | 30 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 10 | ✓✓✓⚑ |
| Duty cycle (%) | 30pulse duration × PRF gives 30% | ✓✓✓ |
| Sonication duration (s) | 40 | ✓✓✓ |
| 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 |
TUS was applied in 30 ms bursts that were generated every 100 ms for a total period of 40 s. The procedure was then immediately repeated for another 40 s in the same area but in the other hemisphere. All TUS was applied prior to the behavioral task.
Exposure 2: TUS of basal forebrain (BF), control region
Target: basal forebrain — “basal forebrain (BF)”
Device: Sonic Concepts · Sonic Concept, Bothell, WA, USA · H115-MR ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 250 | ✓✓✓ |
| Pulse duration (ms) | 30 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 10 | ✓✓✓ |
| Duty cycle (%) | 30pulse duration × PRF gives 30% | ✓✓✓ |
| Sonication duration (s) | 40 | ✓✓✓ |
| 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 |
TUS was applied in 30 ms bursts that were generated every 100 ms for a total period of 40 s. The procedure was then immediately repeated for another 40 s in the same area but in the other hemisphere. All TUS was applied prior to the behavioral task.
Exposure 3: TUS of parietal operculum (POp), control region
Target: other — “parietal operculum (POp)”
Device: Sonic Concepts · Sonic Concept, Bothell, WA, USA · H115-MR ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 250 | ✓✓✓ |
| Pulse duration (ms) | 30 | ✓✓✓ |
| Pulse repetition frequency (Hz) | 10 | ✓✓✓ |
| Duty cycle (%) | 30pulse duration × PRF gives 30% | ✓✓✓ |
| Sonication duration (s) | 40 | ✓✓✓ |
| 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 |
TUS was applied in 30 ms bursts that were generated every 100 ms for a total period of 40 s. The procedure was then immediately repeated for another 40 s in the same area but in the other hemisphere. All TUS was applied prior to the behavioral task.
Flags from extraction
exposures[0].timing.pulse_repetition_frequency_hz— PRF of 10 Hz derived from the stated repetition period (a burst every 100 ms); a unit conversion, not independent arithmetic.sham_type— Paper states a sham TUS condition was included but does not describe how the sham was implemented (e.g., inactive transducer vs other mechanism).n_subjects— The wider fMRI dataset includes 13 macaques, but only 4 macaques participated in the TUS sub-study; n_subjects here reflects only those exposed to ultrasound.exposures[1].target.terms— Basal forebrain (BF) has no matching entry in the target vocabulary; recorded as 'other' with the paper's own label.exposures[2].target.terms— Parietal operculum (POp) has no matching entry in the target vocabulary; recorded as 'other' with the paper's own label.