Virtual Neuroprosthesis: Restoring a Sense of Touch to Amputees

Virtual Neuroprosthesis: Restoring Autonomy to People Suffering From Neurotrauma

The overall goal of this project is to develop a virtual neuroprosthesis in which a facsimile of a neural implant is externalized and housed in a well-controlled microfluidic chamber, thereby abating the intrinsic limitations of highly invasive studies with neural implants. Able-bodied and upper limb amputee subjects will be recruited to control a dexterous artificial hand and arm with electromyogram signals while electroencephalogram (EEG) signals are simultaneously measured. Robotic grip force measurements will be biomimetically converted into electrical pulses similar to those found in the peripheral nervous system to catalyze in vitro nerve regeneration after neurotrauma. The synergistic contributions of this multidisciplinary project will lead to a transformative understanding of the symbiotic interaction of neural plasticity within human-robotic systems. Currently, there is no systematic understanding of how tactile feedback signals can contribute to the neural regeneration of afferent neural pathways to restore somatosensation and improve motor function in amputees fitted with neuroprosthetic limbs. Tackling this problem will be a significant breakthrough for the important field of neuroprosthetics.

Study Overview

• Status: Completed
• Conditions: Amputation
• Intervention / Treatment: Behavioral: Sensory Restoration During Prosthesis Control

Detailed Description

Over one week, neurobehavioral processes will be examined in people controlling a robotic arm and hand to perform simple motor tasks (e.g. fragile object transportation), while a virtual peripheral nerve regeneration protocol provides users with biologically-realistic, idiosyncratic parameters for the restoration of haptic sensation (in double-blind fashion, the cellular neurophysiologists characterizing neural regeneration with microscopy are unaware of subjects' name and condition; and the human-subject experimenters are unaware of the haptic feedback parameter that will be used in the experiment each day, which is entered by the neurophysiologist in a black-box section of the software in the case of microscopic evaluation of nerve regeneration (early part of the project), or which is automatically input by the system in the case of real time impedimetric measurements (later part of the project)).

The main experimental factors are 'haptic feedback', with three modalities: full, partial (nerve-regeneration dependent) and null; and to challenge human control strategy and impose demand on haptic information, the 'transported object weight' (heavy, medium and lightweight).

Recording techniques: Subjects' electroencephalography (EEG), electromyography (EMG) and behavioral performance.

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Florida
    • Boca Raton, Florida, United States, 33431
      • Florida Atlantic University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• No neurological impairment of tactile sensation.

Exclusion Criteria:

• Younger than 18 or older than 65

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Nerve Growth During Prosthesis Control; Determine the optimum conditions that promote sensory restoration in limb-absent people, with an adaptive haptic feedback control law that mimics the experience of neural plasticity. The intervention Sensory Restoration During Prosthesis Control will be used.	Behavioral: Sensory Restoration During Prosthesis Control; Human subjects who use a robotic arm/hand interface will experience variable sensations of touch over time.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Artificial Hand Grasp Performance Metrics	The percentage that grasped objects are successfully transported without slip or drop when controlled by amputees using an artificial hand.	1 week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dorsal Root Ganglia Neurite Regeneration	The length of neurite regeneration 1 week post-axotomy will be quantified. The dorsal root ganglia will be cultured in vitro in a multichannel microelectrode array. The neural culture will be electrically stimulated based on the touch sensations from the artificial hand that is used by amputees. The fingertip touch sensations will be biomimetically converted into pulses that resemble action potentials for the electrical stimulation. The length of neurite regeneration was quantified using NeuronJ to compare images at the beginning and endpoints of the study.	1 week

Collaborators and Investigators

• Sponsor: Florida Atlantic University
• Collaborators: University of Utah; National Institute for Biomedical Imaging and Bioengineering (NIBIB)
• Investigators: Principal Investigator: Erik Engeberg, Ph.D., Florida Atlantic University

Study record dates

Study Major Dates

• Study Start (Actual): October 15, 2017
• Primary Completion (Actual): October 26, 2021
• Study Completion (Actual): October 26, 2021

Study Registration Dates

• First Submitted: June 13, 2018
• First Submitted That Met QC Criteria: June 26, 2018
• First Posted (Actual): July 10, 2018

Study Record Updates

• Last Update Posted (Actual): September 18, 2023
• Last Update Submitted That Met QC Criteria: September 13, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: FloridaAU; R01EB025819 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Gender, ethnicity (if voluntarily disclosed), and nature of upper-limb absence (If applicable) are recorded. This information is reported in corresponding journal and conference publications.
• IPD Sharing Time Frame: Within 1 year after primary completion.
• IPD Sharing Access Criteria: Open access.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No