A person born blind and a person paralysed from a spinal cord injury have historically walked into two different research departments, one focused on visual prostheses and one focused on somatosensory prostheses. A review paper published in Nature Reviews Bioengineering on 1 June 2026 argues that after fifty years of parallel engineering, the two departments are now working on the same problem.

The paper, “Restoring vision and touch with cortical microstimulation,” was press-released by Chalmers University of Technology on 30 June 2026 at 07:00 Central European Time. Its lead author is Giacomo Valle, assistant professor in the Signal Processing and Biomedical Engineering department at Chalmers. Co-authors are Denise Oswalt, Robert A. Gaunt of the University of Pittsburgh, Pieter Roelfsema of the Netherlands Institute for Neuroscience, Charles M. Greenspon of the University of Chicago, and Eduardo Fernandez of Miguel Hernández University in Spain. The paper carries the digital object identifier 10.1038/s44222-026-00449-z.

The argument the review makes is that visual cortical prostheses (VCPs) and somatosensory cortical prostheses (SCPs) share the same underlying engineering problem: how to deliver patterned electrical microstimulation into cortical tissue such that the recipient perceives structured, useful information. VCPs deliver microstimulation to visual cortex to evoke phosphenes for the blind. SCPs deliver microstimulation to somatosensory cortex to evoke touch percepts for people with limb loss or spinal cord injury. The engineering constraints, the electrode array designs, the stimulation waveforms, the tissue-encapsulation problems, the closed-loop feedback questions, and the perceptual-learning challenges have converged.

Why this is a research milestone and not a clinical one

The paper is a review, not a new patient trial. It does not report a new device, a new implant, a new clinical result, or a new regulatory milestone. Its editorial value is the synthesis argument itself: that a hospital of the future would have a single “sense restoration” department, staffed by clinicians and engineers trained on cortical microstimulation as a unified discipline, treating both sight-loss and touch-loss patients through the same underlying platform.

Valle himself is the anchor for the argument. His prior primary-research paper (Valle et al., “Tactile edges and motion via patterned microstimulation of the human somatosensory cortex,” Science 2025) demonstrated that somatosensory cortical microstimulation can convey both static shape information and dynamic motion cues to a human participant with a spinal cord injury, using patterned stimulation at spatial and temporal resolutions comparable to natural touch. That earlier Science paper is a substantive result on the SCP side. The Nature Reviews Bioengineering review paper pulls the SCP side into conversation with the VCP side, where Fernandez, Roelfsema, and their collaborators have made comparable progress in evoking structured phosphene percepts in the visually impaired.

The visual and somatosensory prosthesis lineage

The visual cortical prosthesis line traces to William Dobelle’s implants at Columbia in the 1970s and 1980s, and has continued through the Second Sight Argus II retinal implant (later liquidated in 2020), the Orion cortical implant programme continued through Cortigent, and current implantable and non-implantable programmes led by Fernandez’s Miguel Hernández group in Spain and the Netherlands Institute for Neuroscience under Roelfsema. Fernandez’s group implanted a Utah array in the visual cortex of a legally blind volunteer for six months in 2020 and 2021 and published intelligible phosphene-percept results in the Journal of Clinical Investigation.

The somatosensory cortical prosthesis line traces to Miguel Nicolelis’s animal experiments in the 2000s, and has continued through the Pittsburgh Cortical Bidirectional Brain-Computer Interface programme led by Robert Gaunt with the DARPA HAPTIX programme, and now through Valle’s own work at Chalmers connecting the somatosensory microstimulation substrate to prosthetic-hand grasp control in real time.

The review argues that both lines have arrived at the same engineering waypoint at roughly the same time, and that the substantive next-generation work belongs to whichever teams treat cortical microstimulation as a single discipline. Fernandez, Roelfsema, Gaunt, and Valle are those teams.

What to watch

The first signal is whether a shared engineering standard for cortical microstimulation platforms emerges. Different groups currently use different Utah array formulations, different stimulation waveforms, different safety windows, and different perceptual-mapping calibration protocols. A published or agreed cross-group standard would be a marker of the “single discipline” thesis translating into practice.

The second signal is whether a commercial platform emerges to serve both indications through one hardware line. Cortigent currently focuses on visual cortical implants. Blackrock Neurotech supplies research-grade Utah arrays used by both VCP and SCP groups but has not offered a clinical-grade platform for either indication. A single-vendor clinical-grade platform serving both cohorts would validate the review’s thesis commercially.

The third signal is a first patient who receives both a VCP and an SCP as part of a combined restoration programme. That is a substantial regulatory and surgical undertaking. Its absence is the most concrete gap between the review’s synthesis argument and clinical reality.

Sources

• Valle, Oswalt, Gaunt, Roelfsema, Greenspon, Fernandez. “Restoring vision and touch with cortical microstimulation” (Nature Reviews Bioengineering, 1 June 2026, DOI 10.1038/s44222-026-00449-z)
• Chalmers University of Technology press release, 30 June 2026, 07:00 CET (via Cision News)
• Giacomo Valle institutional page (Chalmers Electrical Engineering)
• Valle et al. “Tactile edges and motion via patterned microstimulation of the human somatosensory cortex” (Science 2025)
• Fernandez et al. Utah array in visual cortex of a legally blind volunteer (Journal of Clinical Investigation, 2021)
• Inside BCI: Stanford Deo precentral gyrus mosaic, 28 June 2026 · Rockefeller ventral premotor cortex abstract-thought decoding, 26 May 2026 · Meta Brain2Qwerty v2 non-invasive MEG, 30 June 2026