19 Sept 2025 · 2 min
Neuralink builds a patient-specific head model in three steps: a silicone scalp mold mixed with skin-tone dye, a machined plastic skull cap shaped to match the patient's anatomy, and a brain proxy poured from a custom hydroshell based on the patient's MRI scan.
We have these custom scalp molds that are patient-specific. We're gonna mix some silicone together, add some dye to mimic the skin tone. And then pour it into the mold. 4 hours later, we'll demold the silicone, and we'll have a patient-specific scalp. Step 2 would be the skull cap. They actually machine skulls out of a block of plastic. You'll see the machinist go in and an anatomically accurate skull come out of a chunk of plastic. Third step will be assembling the brain. That starts actually the night before, where we will pour a custom hydroshell into a proxy mold. And the mold is built from the MRI of the patient that we're building the brain from.
