Wireless intraoral tongue control of an assistive robotic arm for individuals with tetraplegia

Abstract Background For an individual with tetraplegia assistive robotic arms provide a potentially invaluable opportunity for rehabilitation. However, there is a lack of available control methods to allow these individuals to fully control the assistive arms. Methods Here we show that it is possible for an individual with tetraplegia to use the tongue to fully control all 14 movements of an assistive robotic arm in a three dimensional space using a wireless intraoral control system, thus allowing for numerous activities of daily living. We developed a tongue-based robotic control method incorporating a multi-sensor inductive tongue interface. One abled-bodied individual and one individual with tetraplegia performed a proof of concept study by controlling the robot with their tongue using direct actuator control and endpoint control, respectively. Results After 30 min of training, the able-bodied experimental participant tongue controlled the assistive robot to pick up a roll of tape in 80% of the attempts. Further, the individual with tetraplegia succeeded in fully tongue controlling the assistive robot to reach for and touch a roll of tape in 100% of the attempts and to pick up the roll in 50% of the attempts. Furthermore, she controlled the robot to grasp a bottle of water and pour its contents into a cup; her first functional action in 19 years. Conclusion To our knowledge, this is the first time that an individual with tetraplegia has been able to fully control an assistive robotic arm using a wireless intraoral tongue interface. The tongue interface used to control the robot is currently available for control of computers and of powered wheelchairs, and the robot employed in this study is also commercially available. Therefore, the presented results may translate into available solutions within reasonable time

Referred Sensation Areas in a Bilateral Toes Amputee

Various mechanisms in generating phantom limb pain (PLP) have been hypothesized in the literature. However, there still is no clear understanding of how PLP develops and why it presents. Amputation leads to permanent anatomical and physiological changes of the neural path previously supplying the brain with sensory input, as well as to formation of referred sensation areas (RSAs) on the stump or its vicinity. Sensations may be evoked in the lost body part upon stimulation of RSAs that may be exploited as artificial sensory input. In this work, we present the analysis of RSA maps from a 45-year-old female with bilateral toes amputation. Maps of the RSAs were identified in eight sessions over 107 days, characterized by dynamics in both location and type of associated evoked sensation. The evoked sensations were reported to be felt like current through and brushing of the phantom toes at low intensities close to the sensation threshold. Sensations evoked by electrical stimuli delivered through electrodes covering one or more RSAs approximated the sensation of summation of sensations evoked by mechanical stimuli (light brushing). No painful evoked sensations were observed