UC Berkley, the University of California proposed in 2011 in a paper; the benefits and challenges of BCI (the long-lasting brain-computer interface). all this is not even comparable to the Neural dust which uses ultrasound compared to other similar devices that use electoral magnetic waves.

2. The Neural Dust is wirelessly powered nerve sensors

Before the neural dust, Brain-Machine Interaction (BMI) has been a challenge over years in medical history. Until the low power CMOS circuit coupled with ultrasonic power delivery.
The neural dust can stay in your body for over a number of years.
The time the Nueral Dust came in with implantable nuearal interface system, powered with 100 microsecond and 6 times nanosecond ultra sound.
Elon Musk's mind-reading tech could take a big leap forward