Towards a New Sense of Artificial Touch for People with Tetraplegia

Restoring the sense of touch to individuals who have lost it due to spinal cord injury has long been one of the most ambitious goals in neuroscience research. Today, thanks to the work of researchers at the University of Pittsburgh School of Medicine in collaboration with the University of Chicago, we are one step closer to making it a reality.

In a new study published in Nature Communications, participants-individuals with tetraplegia following spinal cord injury—were able to explore digital objects and perceive them through an entirely artificial sense of touch. Unlike previous experiments, where the sensations produced were often vague and indistinct, researchers introduced a crucial innovation: allowing users to personalise the electrical stimulation that generates tactile perception.

This approach enabled participants to associate each object with a unique and consistent sensation. Some described the feeling of stroking the warm fur of a cat, others the smooth, cold surface of an apple, or the stiffness of a key. Although subjective, the sensations were vivid, realistic, and recognisable.

The system used is a brain-computer interface (BCI) - a technology that translates brain activity into signals capable of restoring or enhancing impaired bodily functions. In this case, by stimulating the brain directly, researchers were able to evoke tactile sensations in the participants’ paralysed hands.

In previous years, Pitt researchers had already demonstrated that artificial touch, integrated into a mind-controlled robotic arm, could improve movement precision. However, the sensations experienced were limited and did not vary depending on the object being touched. With this new study, the path is opening to a much more sophisticated and customisable sense of artificial touch.

During the experiment, participants successfully distinguished five different objects displayed on a screen, relying solely on sensations generated by brain stimulation. Although recognition was not perfect, it was significantly above chance, proving that the approach is effective and can be further refined.

This marks an important step towards the development of artificial limbs that not only move naturally but also “feel” as if they are part of the body—a breakthrough that could transform the lives of people with paralysis, making their interaction with the external world more realistic, intuitive, and meaningful.

Read the press release: “Artificial Sense of Touch, Improved”