3D Printing Creates Electrodes Tailored to Individual Brains

To record brain activity, neurosurgeons place sensors called bioelectrodes on the brain’s surface. These are thin sheets that capture the signals emitted by neurons. The problem is that they are manufactured with a one-size-fits-all design, intended to work for all patients equally, when in reality the specific arrangement of the cortex’s folds, gyri, and sulci varies from person to person depending on age, sex, weight, or height.

A team from Pennsylvania State University, led by Professor Tao Zhou, has just published an alternative in Advanced Materials: 3D-printed hydrogel bioelectrodes based on the patient’s own MRI scan.

3D-printed electrodes that are perfectly adapted to the geometry of human brain models.

The workflow for creating the custom sensor is simpler than it seems. An MRI scan serves as the starting point. Based on this, a finite element analysis is performed—“a process that creates a detailed simulation of a person’s neural structure”—and a 3D model is reconstructed. Software then designs an electrode whose shape follows the specific ridges and grooves of that brain. Finally, that design is printed using direct ink writing.