Brain-computer interfaces (BCIs) have long been associated with complex surgeries, implanted electrodes, and invasive procedures. When most people hear the term, they envision wires and chips embedded in the brain. However, a new wave of innovation, particularly emerging from China, is challenging this perception by developing noninvasive BCIs that use focused ultrasound technology instead of implants or incisions. This approach offers a quieter, less intrusive way to interact with and potentially stimulate brain activity.
One notable company leading this frontier is Gestala, a startup founded in Chengdu with offices in Shanghai and Hong Kong. Gestala is pioneering the use of focused ultrasound to both stimulate and study brain activity. While ultrasound technology is traditionally known for its use in medical imaging, such as prenatal scans, Gestala and others are adapting it to target neural circuits within the brain. This method differs fundamentally from the more common BCI systems that rely on electrodes to detect electrical signals from neurons, like Neuralink, which implants tiny threads inside the brain to record neural activity.
Focused ultrasound operates by sending high-frequency sound waves at specific intensities and focal points. These sound waves can influence neural activity in targeted brain regions without the need for surgical intervention. This technique has an established medical history, with focused ultrasound treatments already approved for conditions such as Parkinson’s disease, uterine fibroids, and certain tumors. This clinical background provides a solid foundation for companies like Gestala to build upon as they explore new applications in brain stimulation and monitoring.
Gestala’s initial product targets chronic pain by focusing on the anterior cingulate cortex, a brain region closely linked to the emotional perception of pain. Early pilot studies have shown promising results, with some patients experiencing a reduction in pain intensity lasting up to a week after treatment. The company's first-generation device is designed as a stationary system to be used in clinical settings, where patients would visit hospitals for treatment sessions. Looking ahead, Gestala envisions developing a wearable helmet that patients could use at home under supervision. Beyond chronic pain, the company has ambitious plans to expand its technology to address other neurological and psychiatric conditions such as depression, stroke rehabilitation, Alzheimer’s disease, and sleep disorders. Each of these conditions involves complex and distinct brain networks, posing significant clinical challenges.
In addition to stimulation, Gestala and other startups are investigating whether ultrasound can be used to interpret brain activity. The theoretical concept is straightforward: a device could detect patterns of neural activity associated with specific conditions like chronic pain or depression and then deliver targeted stimulation in response. Unlike implant-based systems that capture electrical signals from limited brain areas, ultrasound-based systems might have the potential to access broader regions of the brain. This possibility has attracted considerable interest from researchers. However, reliably translating ultrasound signals into meaningful brain activity data remains a substantial engineering challenge.
China is not the only country investing in ultrasound BCI technology. In the United States, OpenAI recently announced a significant investment in Merge Labs, a startup co-founded by OpenAI CEO Sam Altman and researchers affiliated with Forest Neurotech. Merge Labs’ public materials highlight ambitions to restore lost abilities, promote healthier brain states, and deepen human connection with advanced artificial intelligence. Although these goals are lofty and promising, experts caution that real-world applications for such technologies are still several years away.
Despite the excitement, ultrasound-based BCIs face several technical hurdles. A major challenge is the human skull, which weakens and distorts sound waves, complicating efforts to obtain precise neural signals. In research environments, detailed neural readouts have often required special implants or modifications that allow ultrasound to pass more effectively than bone. Another limitation is that ultrasound primarily measures changes in blood flow rather than the electrical firing of neurons. Blood flow changes occur more slowly, which limits ultrasound’s suitability for applications requiring rapid, detailed signal decoding, such as real-time speech translation. This means that while ultrasound stimulation itself presents one set of challenges, accurately reading brain activity through ultrasound is an even more complex problem.
Currently, ultrasound BCI technology remains experimental and is not yet available for consumer use. There are no brain helmets or home devices on store shelves. Nonetheless, the potential impact of noninvasive ultrasound devices on medical treatment is significant. If such technology can effectively reduce chronic pain or support mental health therapies without the risks and discomfort of brain surgery, it could open new avenues for patient care.
However, as ultrasound BCIs evolve to analyze brain states and potentially gather sensitive mental data, privacy concerns become paramount. Brain-related information is profoundly personal, and