Neuroprosthetic Devices: i-HAND

Millions of people are paralyzed or have suffered an amputation. Although these people can still see the object they may wantto reach, for example a glass of wine, and can still process in their brains the specific commands to pursue this goal, the actioncannot be completed due to, for example, a spinal cord injury or due to the fact that the arm has been amputated. Given that in mostcases the brain of these persons is intact, the possibility of reading brain signals would allow the development of Neuroprostheticdevices, such as a robot arm that is driven by neural activity.These technological and scientific advances connect the amputee more intimately with their prosthetic limb, meaning we cannow focus more on how the prosthesis is embodied. In other words, to what extent does the prosthetic limb feel like part of thebiological body? Does your brain treat it as such?We have a good understanding of how our body is mapped in our brain. Both our motor cortex – the movement control centre, ifyou like – and the somatosensory cortex where we process a wide range of touch sensations are organisedsomatotopically. Thismeans each area of our body corresponds to a specific area of the primary motor and sensory cortices. Importantly, this mappingdoes not disappear after the loss of a limb.This means we have an opportunity to connect prostheses, through muscles and peripheral nerves, to the parts of the brain thatwould have controlled and sensed the biological body part. But it may also allow us to measure embodiment, how successfullythe brain accepts the prosthesis as part of the body.Ultimately this line of research, bringing together cognitive neuroscience and biomedical engineering, is not only importantfor designing better prostheses. It is a unique window for understanding how our brain creates and maintains the image of ourbodies – mechanisms that apply equally to amputees and non-amputees.