A Psychometric Platform to Collect Somatosensory Sensations for Neuroprosthetic Use

Abstract

Somatosensory neuroprostheses exploit invasive and non-invasive feedback technologies to restore sensorimotor functions lost to disease or trauma. These devices use electrical stimulation to communicate sensory information to the brain. A sensation characterization procedure is thus necessary to determine the appropriate stimulation parameters and to establish a clear personalized map of the sensations that can be restored. Several questionnaires have been described in the literature to collect the quality, type, location, and intensity of the evoked sensations, but there is still no standard psychometric platform. Here, we propose a new psychometric system containing previously validated questionnaires on evoked sensations, which can be applied to any kind of somatosensory neuroprosthesis. The platform collects stimulation parameters used to elicit sensations and records subjects' percepts in terms of sensation location, type, quality, perceptual threshold, and intensity. It further collects data using standardized assessment questionnaires and scales, performs measurements over time, and collects phantom limb pain syndrome data. The psychometric platform is user-friendly and provides clinicians with all the information needed to assess the sensory feedback. The psychometric platform was validated with three trans-radial amputees. The platform was used to assess intraneural sensory feedback provided through implanted peripheral nerve interfaces. The proposed platform could act as a new standardized assessment toolbox to homogenize the reporting of results obtained with different technologies in the field of somatosensory neuroprosthetics.

Multifaceted understanding of human nerve implants to design optimized electrodes for bioelectronics

“…constant re-calibration of the neural stimulation is required. This process is manually performed by clinicians or experimenters using custom-made platform [25]. Thus, the procedure is expensive, time-consuming and expert-dependent making difficult the home-use of these neurotechnologies.…”

“…In particular, the histological analysis and imaging should be expanded and improved overcoming the difficulty related to analyze implants of very small electrodes (μm) into large nerves (cm). Moreover, standardized and automatic algorithms are necessary to uniformize the datasets across the neurotechnologies to collect somatosensory percepts [25] in order to improve the performance of such devices and their adoption.…”

“…All the data were collected using a purposely-designed psychometric platform for neuroprosthetic applications It indeed allows to collect data using standardized assessment questionnaires and scales, and to perform measurements over time. The psychometric platform is user-friendly and provides clinicians with all the information needed to assess the sensory feedback [25].…”

Multiparametric non-linear TENS modulation to integrate intuitive sensory feedback

“…A sensation characterization procedure was performed at the beginning of each experiment to obtain the subject-specific charge values [65]. Electrical nerve stimulation (TENS) was delivered using Rehamove 3 (Hasomed GmBh, Germany), which is a CE-approved portable and programmable four channels surface stimulator with transcutaneous adhesive electrodes (Circular Electrode Pads 25 mm, TensCare, UK).…”

“…a small pedal pressed with the foot or the pressure of that area of the foot on the floor)' . Since TENS can elicit different types of sensations, each paradigm was also qualitatively described by choosing sensation descriptors (light touch, pressure, vibration, tingling, slow pulsation, stinging, electricity, pain) [65]. Among these descriptors, it is desirable to avoid uncomfortable and unpleasant sensations such as stinging, electricity and pain.…”