Background-Kilohertz frequency alternating currents (KHFAC) produce rapid nerve conduction block of mammalian peripheral nerve and have potential clinical applications in reducing peripheral nerve hyperactivity. The experimental investigation of KHFAC nerve block requires a robust output measure and this has proven to be the block threshold (BT), the lowest current or voltage at which the axons of interest are completely blocked. All significant literature in KHFAC nerve block, both simulations and experimental, were reviewed to determine the block threshold method that was used. The two common methods used are the High-Low method experimentally and the Binary search method for simulations. New Method-Four methods to measure the block threshold (High-Low, High-Low-High, Binary and Random) at three frequencies (10, 20 and 30 kHz) were compared through randomized repeated experiments in the in-vivo rodent sciatic nerve-gastrocnemius model. Results-The literature review showed that more than 50 % of publications did not measure the block threshold. The experimental results showed no statistical difference in the BT value between the four methods. Comparison with Existing Method(s)-However, there were differences in the number of significant onset responses, depending on the method. The run time for the BT determination was the shortest for the High-Low method. Conclusions-It is recommended that all research in electrical nerve block, including KHFAC, should include measurement of the BT. The High-Low method is recommended for most experimental situations but the Binary method could also be a viable option, especially where onset responses are minimal.

The development of neural interfaces to provide improved control and somatosensory feedback from prosthetic limbs has initiated a new ability to probe the various dimensions of embodiment. Scientists in the field of neuroprosthetics require dependable measures of ownership, body representation, and agency to quantify the sense of embodiment felt by patients for their prosthetic limbs. These measures are critical to perform generalizable experiments and compare the utility of the new technologies being developed. Here, we review outcome measures used in the literature to evaluate the senses of ownership, body-representation, and agency. We categorize these existing measures based on the fundamental psychometric property measured and whether it is a behavioral or physiological measure. We present arguments for the efficacy and pitfalls of each measure to guide better experimental designs and future outcome measure development. The purpose of this review is to aid prosthesis researchers and technology developers in understanding the concept of embodiment and selecting metrics to assess embodiment in their research. Advances in the ability to measure the embodiment of prosthetic devices have far-reaching implications in the improvement of prosthetic limbs as well as promoting a broader understanding of ourselves as embodied agents.

This paper presents the design, evaluation, and field experiment of the innovative Adapt- able Human-Swarm Teaming ( α -SWAT) interface developed to support military field operations. Human-swarm teaming requires collaboration between a team of humans and a team of robotic agents for strategic decision-making and task performance. α -SWAT allows multiple human team members with different roles, physical capabilities, or preferences to interact with the swarm via a configurable, multimodal user interface (UI). The system has an embedded task allocation algorithm for the rapid assignment of tasks created by the mission planner to the swarm. The multimodal UI supports swarm visualization via a mixed reality display or a conventional 2D display, human gesture inputs via a camera or an electromyography device, tactile feedback via a vibration motor or implanted peripheral nerve interface, and audio feedback. In particular, the UI system interfacing with the implanted electrodes through a neural interface enables gesture detection and tactile feedback for individuals with upper limb amputation to participate in human-swarm teaming. The multimodality of α -SWAT’s UI adapts to the needs of three different roles of the human team members: Swarm Planner, Swarm Tactician Rear, and Swarm Tactician Forward. A case study evaluated the functionality and usability of α -SWAT to enable a participant with limb loss and an implanted neural interface to assign three tasks to a simulated swarm of 150 robotic agents. α -SWAT was also used to visualize live telemetry from 40 veridical robotic agents for multiple simultaneous human participants at a field experiment.