Temporal Asynchrony but Not Total Energy Nor Duration Improves the Judgment of Numerosity in Electrotactile Stimulation

Frontiers in Bioengineering and Biotechnology

Luca Brayda¹  Maurizio Valle²  Lucia Seminara²  Strahinja Dosen³  Sara Nataletti⁴  Carlo Trompetto⁶  Fabrizio Leo⁷ 

[1] Acoesis Inc., Genoa, Italy;Department of Electrical, Electronic, Telecommunications Engineering and Naval Architecture, University of Genoa, Genoa, Italy;Department of Health Science and Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark;Department of Informatics Bioengineering Robotics, and System Engineering, University of Genoa, Genoa, Italy;Department of Neuroscience, IRCCS Ospedale Policlinico San Martino, Genoa, Italy;Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Sciences, University of Genoa, Genoa, Italy;Robotics, Brain and Cognitive Science Department, Istituto Italiano di Tecnologia, Genoa, Italy;

关键词: sensory substitution;    numerosity judgment;    electrotactile stimulation;    stimulation timing;    tactile feedback;    upper extremity;   

DOI  :  10.3389/fbioe.2020.00555

来源: DOAJ

【 摘 要 】

Stroke patients suffer from impairments of both motor and somatosensory functions. The functional recovery of upper extremities is one of the primary goals of rehabilitation programs. Additional somatosensory deficits limit sensorimotor function and significantly affect its recovery after the neuromotor injury. Sensory substitution systems, providing tactile feedback, might facilitate manipulation capability, and improve patient's dexterity during grasping movements. As a first step toward this aim, we evaluated the ability of healthy subjects in exploiting electrotactile feedback on the shoulder to determine the number of perceived stimuli in numerosity judgment tasks. During the experiment, we compared four different stimulation patterns (two simultaneous: short and long, intermittent and sequential) differing in total duration, total energy, or temporal synchrony. The experiment confirmed that the subject ability to enumerate electrotactile stimuli decreased with increasing the number of active electrodes. Furthermore, we found that, in electrotactile stimulation, the temporal coding schemes, and not total energy or duration modulated the accuracy in numerosity judgment. More precisely, the sequential condition resulted in significantly better numerosity discrimination than intermittent and simultaneous stimulation. These findings, together with the fact that the shoulder appeared to be a feasible stimulation site to communicate tactile information via electrotactile feedback, can serve as a guide to deliver tactile feedback to proximal areas in stroke survivors who lack sensory integrity in distal areas of their affected arm, but retain motor skills.

【 授权许可】

Unknown