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Nudge: Our Mission, Technology, and Approach | Nudge 

science•blog post•View Source
Appreciation
6
Importance
--
Date Added
9.1.25
TLDR
Nudge is building non-invasive ultrasound-based devices for stimulating the brain to combat brain disorders like addiction, chronic pain, and anxiety (and in the future, help everyone with wide-ranging applications like improving mood, focus, and memory). They use ultrasound to modulate brain activity, and there are many recent studies showing surprising promise.
2 Cents
A well-written mission + intro to TUS (transcranial ultrasound stimulation).
Tags

See my entry for the founder's essay  instead (which I enjoyed reading more anyway). It contains the actual notes from my exploration.

#Messy first read-through questions

I also read the Nudge Series A post  and felt like it belonged in the same bookshelf entry.

  • How badly can you damage someone through ultrasound waves?

    • For that matter, what are the potential harms that non-invasive BCI can do?
    • I imagine if it can help / affect human mood or symptoms that much it also has potential to do damage.

  • What is an MRI machine exactly and how does it work? Side effects?

  • How did the original sources test out phased array experiments?

    • Their tech so far seems to just enable the phased array approach, and that seems like the bare minimum.
    • What are the exact dimensions by which you improve the hardware? (And I'm not looking for something vague like "you can get more precise.")

  • Revisit:

    Our initial device is built to ensure we can drive the most robust and powerful effects and is not designed for portability. In parallel, we're building the foundation for another architecture which is meant to be used at home and in everyday life — as easy to use and as ubiquitous as headphones are today. Bringing this technology into the home requires miniaturizing the electronics, using more advanced fabrication techniques for the transducers, building the imaging capabilities from our MRI-guided approach into the device itself, and solving the difficult technical challenges required to personalize stimulation.

  • Evidently a couple of the primary challenges:

    • The skull distorts ultrasound waves (and differently per skull):

      Delivering high-resolution ultrasound through the skull is not like sending sound through air or soft tissue — the skull acts as a highly distorting lens. The acoustic properties of bone vary from person to person, and even small errors in targeting or ultrasound parameters can make the difference between meaningful engagement of a brain circuit and none at all.

    • Also these, but I lowkey don't understand:

      In parallel, we also need to develop the hardware and algorithms for ultrasound-based structural and functional imaging through the skull, create methods to optimize sonication parameters for each individual from neural and physiological readouts, and build a consumer-grade product that "just works". Doing this well requires deep advances in physics modeling, signal processing, hardware design, and real-time feedback systems, alongside an ever-evolving map of how the brain is organized, how it responds, and how it can be guided.

As with all startups, this page will likely update significantly in the future.