Assimilation of virtual legs and perception of floor texture by complete paraplegic patients receiving artificial tactile feedback

Abstract

Spinal cord injuries disrupt bidirectional communication between the patient’s brain and body. Here, we demonstrate a new approach for reproducing lower limb somatosensory feedback in paraplegics by remapping missing leg/foot tactile sensations onto the skin of patients’ forearms. A portable haptic display was tested in eight patients in a setup where the lower limbs were simulated using immersive virtual reality (VR). For six out of eight patients, the haptic display induced the realistic illusion of walking on three different types of floor surfaces: beach sand, a paved street or grass. Additionally, patients experienced the movements of the virtual legs during the swing phase or the sensation of the foot rolling on the floor while walking. Relying solely on this tactile feedback, patients reported the position of the avatar leg during virtual walking. Crossmodal interference between vision of the virtual legs and tactile feedback revealed that patients assimilated the virtual lower limbs as if they were their own legs. We propose that the addition of tactile feedback to neuroprosthetic devices is essential to restore a full lower limb perceptual experience in spinal cord injury (SCI) patients, and will ultimately, lead to a higher rate of prosthetic acceptance/use and a better level of motor proficiency.

A method for creating interactive, user-resembling avatars

“…For example, the systems presented by Rudinskiy et al (2014), Donati et al (2016) or Shokur et al (2016) use VR with an avatar visualization for gait rehabilitation. In this case, an improved avatar visualization would help generating a better sense of immersion and could possibly help with the treatment.…”

“…To mention but a few examples beyond the gaming scene, VR is now widely used in medical applications for physical rehabilitation (Paolini et al, 2013;Baldominos, Saez & Del Pozo, 2015;Draganov & Boumbarov, 2015;Morel et al, 2015;Donati et al, 2016;Shokur et al, 2016), exposure therapy for phobias and post-traumatic stress (Notzon et al, 2015;Cuperus et al, 2016), treatment for addiction (Park et al, 2016) and even autism (Didehbani et al, 2016). Other fields such as architecture and urban planning (Portman, Natapov & Fisher-Gewirtzman, 2015;Luigi et al, 2015) and education (Abulrub, Attridge & Williams, 2011) also benefit from the technology.…”

¿Cómo entender los fenómenos de pasividad? Una revisión crítica de la hipótesis de Frith

“…Sin embargo, el movimiento voluntario es más exigente en su instanciación, pues pareciera exigir que se instancie en el mismo cuerpo del agente, mientras que, para movimientos efectuados a través de un dispositivo o herramienta, parece haber la posibilidad de un soa-remoto o "tele-soa" (cf. Nicolelis et al 2016). Lo anterior evidencia dos puntos.…”

Peer Review #1 of "A method for creating interactive, user-resembling avatars (v0.1)"

“…In the medical field, VR is broadly used for rehabilitation treatments. For example, the systems presented by Rudinskiy et al (2014), Donati et al (2016) or Shokur et al (2016) use VR with an avatar visualization for gait rehabilitation. In this case, an improved avatar visualization would help generating a better sense of immersion and could possibly help with the treatment.…”

“…To achieve that, the industry has turned to motion tracking devices and immersive 3D graphics, including head mounted displays (HMDs), such as Oculus Rift, HTC Vive, and Hololens, and motion tracking technologies, such as Kinect, Wii Remote, Leap Motion, and Virtuix Omni VR treadmill. This recent surge of affordable VR devices expanded the number of VR applications. To mention but a few examples beyond the gaming scene, VR is now widely used in medical applications for physical rehabilitation (Paolini et al, 2013;Baldominos et al, 2015;Draganov and Boumbarov, 2015;Morel et al, 2015;Donati et al, 2016;Shokur et al, 2016), exposure therapy for phobias and post-traumatic stress (Notzon et al, 2015;Cuperus et al, 2016), treatment for addiction (Park et al, 2016) and even autism (Didehbani et al, 2016). Other fields such as architecture and urban planning (Portman et al, 2015;Luigi et al, 2015) and education (Abulrub et al, 2011) also benefit from the technology.…”