Comparison of neural responses to whisker and ultrasound stimulation using a novel dual-stimulation protocol
Ye Yuan, Tian Liu, Jue Wang
Journal of Neuroscience Methods 2025, 418, 110435 · 10.1016/j.jneumeth.2025.110435
Abstract
Background The sensory system allows organisms to perceive and respond to environmental stimuli. This study investigates neural response differences between whisker and ultrasound stimulation in rats to evaluate cortical specificity to sensory inputs. New method A novel dual-stimulation protocol combining a step motor and ultrasound system was developed to alternately stimulate the C2 whisker and corresponding barrel column region. Experiments were conducted under varying stimulation sequences (whisker-ultrasound and ultrasound-whisker) and time intervals (10 ms, 25 ms, and 100 ms). Neural response signals were recorded, and statistical analyses (ANOVA and T-test) were performed to compare response amplitudes and peak latencies. Results Whisker stimulation consistently elicited significantly stronger neural responses than ultrasound stimulation (*p Comparison with existing methods Unlike single-modal whisker or ultrasound stimulation, the dual-stimulation protocol can enhance sensory responses, highlighting its neuromodulatory potential. Conclusion This study reveals distinct cortical activation patterns induced by whisker and ultrasound stimulation. While whisker stimulation is more sensitive, ultrasound stimulation-when optimized for frequency and timing-can effectively modulate neural responses under dual-stimulation protocol. These findings provide insights into ultrasound-based neuromodulation and sensory processing.
Abstract via europepmc.
Exposures
Exposure 1: Ultrasound stimulation of the C2 barrel column at 1, 2, and 4 MHz
Target: primary somatosensory cortex — “C2 whisker barrel column region (barrel cortex)”
Device: other named manufacturer · Siansonic, Inc., China · HIFU transducer (1 MHz, 2 MHz, and 4 MHz) ✓
| Waveform | pulsed | |
|---|---|---|
| Fundamental frequency (kHz) | 1,000, 2,000, 4,000swept | ✓✓✓⚑ |
| Pulse duration (ms) | not reported | ⚑ |
| Pulse repetition frequency (Hz) | 500 | ✓✓✓ |
| Duty cycle (%) | not reported | |
| Sonication duration (s) | not reported | ⚑ |
| 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 | |
| Ispta, domain unspecified (W/cm²) | 0.7 | ✓✓✓⚑ |
Each stimulation session lasted 2 seconds, during which a total of 300 individual stimulations were administered. Ultrasound was delivered in a dual-stimulation protocol alternating with whisker stimulation (whisker-ultrasound or ultrasound-whisker order) at intervals of 10 ms, 25 ms and 100 ms between the two stimuli, with 3 minutes rest between stimulation sequences. Animal skull was removed prior to stimulation to eliminate skull attenuation effects.
Flags from extraction
exposures[0].unspecified_domain.ispta_w_cm2— Domain (free-field vs in-situ) not specified; skull was surgically removed before stimulation so the reported intensity may not correspond to a conventional free-field or in-situ (through-skull) measurement.exposures[0].timing.pulse_duration_ms— Paper gives PRF (500 Hz) but never states an individual pulse/burst duration or duty cycle, so pulse duration cannot be determined from the text.exposures[0].timing.sonication_duration_s— Paper states each 'stimulation session' lasted 2 s with 300 individual stimulations inside it, but does not clarify the duration of a single uninterrupted sonication train.n_sessions_per_subject— Paper describes a single recording day per animal with multiple stimulation sequences/intervals but never states an explicit session count.exposures[0].fundamental_frequency_khz— Three frequencies (1, 2, 4 MHz) were tested in three separate groups of animals (n=12 each) rather than in the same subjects; treated as one frequency-response exposure per instructions since intensity/PRF were held constant across frequencies.