Peng Lei, founder of the invasive brain-computer interface startup NeuroXess, abandoned his competitive advantage in electrode implants to pursue ultrasound brain stimulation instead, a shift driven by his conviction that the brain's complexity cannot be captured by point-like electrode readings alone. His new company, Gestala, raised approximately 13.7 billion yen (roughly $92 million USD) within six months of founding, betting on a technology that no one has yet successfully commercialized for non-invasive brain reading through an intact skull.

The decision puzzled industry observers. Peng Lei had already established NeuroXess as a leading invasive brain-computer interface (BCI) company in China, developing technology similar to Neuralink that enables paralyzed people to operate digital devices and produce synthesized speech. Yet he chose to start over with ultrasound, a fundamentally different approach that requires no surgical implants. Understanding why reveals both the genuine scientific promise of ultrasound BCI and the significant gaps between what researchers have proven and what companies like Gestala are claiming.

What Makes Ultrasound Different From Electrode Implants?

Peng Lei's core insight centers on a fundamental limitation of electrode-based BCIs. Electrodes can only read electrical signals from the specific point in the brain where they are inserted. This creates what engineers call a "local, point-like signal." If an electrode is placed in the motor cortex, it captures motor signals from that region. But the brain's complex functions arise from the coordination of neural circuits connecting distant brain regions. Since it is physically impossible to insert electrodes without gaps from the surface of the cortex to deep brain areas, the electrode method cannot capture how the entire brain coordinates its activity.

Peng Lei named his company Gestala after the psychological concept of Gestalt, which holds that "the whole is greater than the sum of its parts." This philosophical stance guided his decision to pursue ultrasound, a non-invasive technology that can theoretically reach deep brain structures and multiple targets simultaneously without surgery.

How Does Ultrasound Actually Stimulate the Brain?

Ultrasound brain stimulation works through a mechanical process, not heat. When ultrasound passes through tissue, it creates nanoscale compression and particle displacement, generating a force called acoustic radiation force. To regulate nerves without damaging them, the intensity must remain low, less than 500 milliwatts per square centimeter in spatial peak temporal average intensity, which produces minimal temperature change of less than 0.1 degrees Celsius.

The mechanism operates at the molecular level. Mechanosensitive ion channels in cell membranes, particularly Piezo1, respond to the acoustic force. Piezo1 is the most sensitive mechanotransduction channel, responding to a tiny force of just 10 piconewtons. In a 2024 mouse experiment, when Piezo1 and Piezo2 in the motor cortex were disabled, the success rate of motor responses due to ultrasound stimulation decreased significantly, confirming that these channels are essential for ultrasound neuromodulation.

The process is straightforward at the cellular level: sound pushes the cell membrane, channels open, ions flow, and the excitability of the nerve changes. This molecular-level pathway is well understood in animal studies.

Where Is Ultrasound BCI Actually Proven to Work?

Gestala's first-generation product targets chronic pain treatment, focusing on a brain region called the anterior cingulate cortex. This choice reflects where ultrasound BCI has the strongest independent scientific support. The effect of ultrasound on chronic pain is not unique to Gestala; it is one of the applications most supported by peer-reviewed clinical research.

A randomized crossover trial published in the PAIN journal in 2024 tested 20 patients with chronic pain who received 40 minutes of ultrasound stimulation, either real or sham, to the anterior cingulate cortex. The stimulation was well tolerated, with no serious adverse events reported. Side effects were generally mild and disappeared within 24 hours.

In the same year, the Journal of Neuroscience demonstrated for the first time in humans that low-intensity focused ultrasound can non-invasively and selectively regulate this brain region, reducing the perception of acute pain and autonomic nerve responses. In another exploratory study targeting neuropathic pain, the median pain score decreased after four weeks of treatment.

Peng Lei does not position this pain treatment as a replacement for ordinary painkillers. Instead, he targets severe cases where the risk of drug dependence has already emerged, or patient groups unsuitable for long-term, high-dose medication due to complications. In the first phase of clinical trials, he focuses on subtypes of neuropathic pain, including postherpetic neuralgia, fibromyalgia, trigeminal neuralgia, and cancer pain.

What Are the Key Differences Between Ultrasound "Writing" and "Reading"?

Understanding Gestala's technology requires distinguishing between two separate ultrasound systems that operate under the same umbrella term. The company is attempting to integrate these into a closed loop, but they are at very different stages of scientific maturity.

• Ultrasound "Writing" (Stimulation): Transcranial Focused Ultrasound, or tFUS, focuses ultrasound from outside the skull onto a single point in the brain to excite or inhibit neural activity at that focal point. This technology is on a scientifically solid foundation, with multiple peer-reviewed studies confirming its safety and efficacy in animals and early human trials.
• Ultrasound "Reading" (Brain Imaging): Functional ultrasound imaging, or fUS, utilizes the phenomenon where local blood flow increases when nerves are active, using ultra-high-speed ultrasound to image blood flow changes in microvessels to estimate what the brain is trying to do. This approach has not yet been achieved by anyone in the world through an intact skull, making it the frontier of the technology.
• Closed-Loop Integration: Gestala's vision is to combine reading and writing into a continuous feedback loop: read brain activity, judge what the person intends, and write stimulation commands back to the brain. This integration remains largely theoretical for the "reading" component.

How Does Ultrasound Compare to Existing Non-Invasive Brain Stimulation?

Ultrasound offers significant advantages over conventional non-invasive brain stimulation methods. Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS) have a coarse spatial resolution of several centimeters, can only target a wide range of the brain's surface, and are difficult to reach deep areas. Ultrasound can be focused on a single point in millimeter units and can act on deep areas such as the thalamus and hippocampus, as well as the cortex, by selecting multiple targets. The reach depth is reported to be six to seven centimeters.

This combination of non-invasiveness with the ability to reach deep, multi-target areas represents what researchers call the "blank space" in brain stimulation technology. Ultrasound fills a gap that neither invasive electrodes nor conventional non-invasive methods can address.

Steps to Evaluate Emerging Brain-Computer Interface Claims

• Distinguish Technology Components: When evaluating ultrasound BCI companies, separate the "writing" (stimulation) and "reading" (imaging) components. A company may have proven one while the other remains experimental. Ask which specific functions have been tested in humans versus animals.
• Check for Independent Peer Review: Look for results published in established journals by researchers outside the company. Gestala's pain treatment claims are supported by independent studies in PAIN journal and the Journal of Neuroscience, which strengthens credibility compared to company-only claims.
• Examine Clinical Trial Design: Assess whether human studies used proper controls, such as sham stimulation groups. The 2024 PAIN journal study used a randomized crossover trial with sham controls, a gold standard that increases confidence in the findings.
• Understand the Indication Focus: Companies often start with the easiest medical application. Gestala's focus on chronic pain is strategically sound because ultrasound's effect on pain has the strongest independent research support, not because pain treatment is the ultimate goal.

What Remains Unproven in Ultrasound BCI?

The critical gap lies in the "reading" side of the equation. Gestala claims it can use functional ultrasound imaging to read brain activity through an intact skull, but this has not yet been achieved by any research team in the world. The company's vision of a closed-loop system that reads brain intent, judges it, and writes stimulation back depends on solving this unsolved problem.

Peng Lei's background gives him credibility to attempt this challenge. He holds a degree in precision instruments from the University of Science and Technology of China, a degree in computer science from The Hong Kong Polytechnic University, and a PhD in neuroscience from the Institute of Brain-inspired Intelligence at Fudan University. His mentor is Feng Jianfeng, an international authority on computational neuroscience. Counting from a catering software-as-a-service company acquired by Alibaba, Gestala is his sixth startup. A person who has bundled engineering, neuroscience, and artificial intelligence into a single career history is betting his reputation on solving what others have not.

The 13.7 billion yen funding round suggests investors believe in Peng Lei's vision, but the technology's success depends on whether ultrasound can truly read brain activity through an intact skull. Until that is demonstrated in humans, Gestala's most immediate commercial opportunity remains what the science already supports: non-invasive brain stimulation for chronic pain treatment.