Prof Christopher James, an expert in neural engineering at the University of Warwick, who uses non-invasive techniques in his own research, explains that it is currently not possible to put information into a brain using just the surface of the scalp.

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When using the NovoTTF-100A System, a health care professional places electrodes on the surface of the patient's scalp to deliver low-intensity, changing electrical fields called "tumor treatment fields" (TTFs) to the tumor site.

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Under anesthesia, an incision is made in the scalp, a hole is drilled in the skull, and the device is placed on the surface of the brain.

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