Olfactory Hacking via Skull Ultrasound

Researchers report a head‑mounted focused‑ultrasound device that, when placed on the forehead and aimed at the olfactory bulb using MRI guidance, elicited distinct smell sensations (fresh air, garbage, ozone, campfire) without releasing any chemicals. The prototype is bulky and handheld now but plausibly miniaturizable for wearable or clinical use. — If scalable, this creates a new vector for non‑consensual sensory influence, novel therapeutic prosthetics for anosmia, and regulatory questions about neuroprivacy and advertising.