A Wearable Device for Hand Sensorimotor Rehabilitation Through Augmented Sensory Feedback.

The loss of sensitivity of the upper limb due to central or peripheral neurological injuries severely limits the ability to manipulate objects, hindering personal independence. Non-invasive augmented sensory feedback techniques are used to promote neural plasticity hence to restore the grasping function. We devised a wearable device for hand sensorimotor rehabilitation capable of reliably detect transient tactile events based on custom piezoelectric polyvinylidene fluoride (PVDF) sensors and deliver discrete bursts of vibrations upon these events. We integrated the sensors into a fabric glove and tested the device in a pilot bench test exploring its ability to detect object contact and release as well as object slippage. Due to their broad bandwidth, the sensors proved to be suitable for both the applications: they responded with clear peaks when touching or releasing the object and increased the high-frequency content of the signal during slippage.

Muscle synergies in archery: an explorative study on experienced athletes with and without physical disability.

Archery technique requires a coordinated activation of shoulder girdle and upper extremity muscles to perform a successful shot. The analysis of muscle synergies can provide information about the motor strategy that underlies the shooting performance, also supporting the investigation of motor impairments in athletes with disability. For this purpose, electromyographic (EMG) data from five muscles were collected from a non-disabled and a W1 category Paralympic athlete, and muscle synergies were extracted from EMG envelopes using non-negative matrix factorization. Muscle synergies analysis revealed features of the motor strategy specific to the athletes' shooting technique, such as the contribution of the biceps muscle instead of the posterior deltoid during the arrow drawing and target aiming in the Paralympic athlete compared to the non-disabled athlete. It is concluded that the evaluation of the muscle synergies may be a valuable tool for exploring the motor strategies adopted by athletes with disability, providing useful information to improve athletic performance and possibly prevent the risk of injury.