Integrating a prosthetic hand to amputees with seamless neural compatibility presents a grand challenge to neuroscientists and neural engineers for more than half century. Mimicking anatomical structure or appearance of human hand does not lead to improved neural connectivity to the sensorimotor system of amputees. The functions of modern prosthetic hands do not match the dexterity of human hand due primarily to lack of sensory awareness and compliant actuation. Lately, progress in restoring sensory feedback has marked a significant step forward in improving neural continuity of sensory information from prosthetic hands to amputees. However, little effort has been made to replicate the compliant property of biological muscle when actuating prosthetic hands. Furthermore, a full-fledged biorealistic approach to designing prosthetic hands has not been contemplated in neuroprosthetic research. In this perspective article, we advance a novel view that a prosthetic hand can be integrated harmoniously with amputees only if neural compatibility to the sensorimotor system is achieved. Our ongoing research supports that the next-generation prosthetic hand must incorporate biologically realistic actuation, sensing, and reflex functions in order to fully attain neural compatibility.
| (i) | Generative BMI models of motor signal decoding: a generative brain-machine interface (BMI) model can provide a feedforward control strategy for more biomimetic and flexible neuroprosthetic control for reaching and grasping [17, 18]. This technology is in evaluation in nonhuman primates. |
| (ii) | Recognition of motor intention using high-density EMG: novel pattern recognition methods can improve predicting motor intentions from high-density electromyogram (EMG) signals of residual muscles in amputated limb, which enables an intuitive control of prosthetic movements [19]. This technology has been applied to amputee control of prosthetic hand. |
| (iii) | Neuromorphic models of neuromuscular system: it is feasible to restore neuromuscular reflex process for cable-driven prosthetic hands with human-like traits, using neuromorphic hardware to perform fast computation of physiologically realistic models and to emulate human-like reflex in real time [6]. This technology is now in evaluation for human application. |
| (iv) | Noninvasive tactile sensory feedback: we have demonstrated the feasibility to utilize an electrically evoked tactile sensation (ETS) as a natural way to furnish sensory information to amputee’s brain. This sensory feedback technique is noninvasive, has long-term stability, and can supply finger-specific, multiple modalities of natural sensory information to amputees [5, 20]. This technology is currently undergoing evaluation of functional benefits in amputee subjects. |
| (v) | Selective slip sensors mimicking the Ruffini endings: a flexible tactile sensor inspired by the structure of fingerprints and the function of the Ruffini endings with selective sensitivity to static and sliding friction forces may enable prosthetic hand to handle slippage during grasping [21]. The proof of concept of this technology is completed. The device is in the initial stage for human application. |
| (vi) | Tendon-driven soft prosthetic hand: a tendon-driven soft prosthetic hand with finger body made of continuum spiral structure of super-elastic nitinol alloy material can have natural compliance for grasping objects using a simple control strategy [22]. This device is in refinement of structural design and functional evaluation. |
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |