Experiencing an Elongated Limb in Virtual Reality Modifies the Tactile Distance Perception of the Corresponding Real Limb

Overview

Journal eNeuro

Specialty Neurology

Date 2024 Jun 6

PMID 38844346

Authors

Francois Le Jeune

Marco DAlonzo

Valeria Piombino

Alessia Noccaro

Domenico Formica

Giovanni Di Pino

Affiliations

Soon will be listed here.

Abstract

In measurement, a reference frame is needed to compare the measured object to something already known. This raises the neuroscientific question of which reference frame is used by humans when exploring the environment. Previous studies suggested that, in touch, the body employed as measuring tool also serves as reference frame. Indeed, an artificial modification of the perceived dimensions of the body changes the tactile perception of external object dimensions. However, it is unknown if such a change in tactile perception would occur when the body schema is modified through the illusion of owning a limb altered in size. Therefore, employing a virtual hand illusion paradigm with an elongated forearm of different lengths, we systematically tested the subjective perception of distance between two points [tactile distance perception (TDP) task] on the corresponding real forearm following the illusion. Thus, the TDP task is used as a proxy to gauge changes in the body schema. Embodiment of the virtual arm was found significantly greater after the synchronous visuotactile stimulation condition compared with the asynchronous one, and the forearm elongation significantly increased the TDP. However, we did not find any link between the visuotactile-induced ownership over the elongated arm and TDP variation, suggesting that vision plays the main role in the modification of the body schema. Additionally, significant effect of elongation found on TDP but not on proprioception suggests that these are affected differently by body schema modifications. These findings confirm the body schema malleability and its role as a reference frame in touch.

References

Castro F, Lenggenhager B, Zeller D, Pellegrino G, DAlonzo M, Pino G . From rubber hands to neuroprosthetics: Neural correlates of embodiment. Neurosci Biobehav Rev. 2023; 153:105351. PMC: 10582798. DOI: 10.1016/j.neubiorev.2023.105351. View

de Vignemont F . Body schema and body image--pros and cons. Neuropsychologia. 2009; 48(3):669-80. DOI: 10.1016/j.neuropsychologia.2009.09.022. View

DAngelo M, di Pellegrino G, Seriani S, Gallina P, Frassinetti F . The sense of agency shapes body schema and peripersonal space. Sci Rep. 2018; 8(1):13847. PMC: 6138644. DOI: 10.1038/s41598-018-32238-z. View

Longo M, Azanon E, Haggard P . More than skin deep: body representation beyond primary somatosensory cortex. Neuropsychologia. 2009; 48(3):655-68. DOI: 10.1016/j.neuropsychologia.2009.08.022. View

Spinelli G, Tieri G, Pavone E, Aglioti S . Wronger than wrong: Graded mapping of the errors of an avatar in the performance monitoring system of the onlooker. Neuroimage. 2017; 167:1-10. DOI: 10.1016/j.neuroimage.2017.11.019. View

Taylor-Clarke M, Jacobsen P, Haggard P . Keeping the world a constant size: object constancy in human touch. Nat Neurosci. 2004; 7(3):219-20. DOI: 10.1038/nn1199. View

Bekrater-Bodmann R, Foell J, Diers M, Flor H . The perceptual and neuronal stability of the rubber hand illusion across contexts and over time. Brain Res. 2012; 1452:130-9. DOI: 10.1016/j.brainres.2012.03.001. View

Pyasik M, Tieri G, Pia L . Visual appearance of the virtual hand affects embodiment in the virtual hand illusion. Sci Rep. 2020; 10(1):5412. PMC: 7096421. DOI: 10.1038/s41598-020-62394-0. View

Romano D, Caffa E, Hernandez-Arieta A, Brugger P, Maravita A . The robot hand illusion: inducing proprioceptive drift through visuo-motor congruency. Neuropsychologia. 2014; 70:414-20. DOI: 10.1016/j.neuropsychologia.2014.10.033. View

10.

Pinardi M, Raiano L, Formica D, Pino G . Altered Proprioceptive Feedback Influences Movement Kinematics in a Lifting Task. Annu Int Conf IEEE Eng Med Biol Soc. 2020; 2020:3232-3235. DOI: 10.1109/EMBC44109.2020.9176252. View

11.

Vidotto G, Anselmi P, Robusto E . New Perspectives in Computing the Point of Subjective Equality Using Rasch Models. Front Psychol. 2020; 10:2793. PMC: 6927926. DOI: 10.3389/fpsyg.2019.02793. View

12.

Longo M, Haggard P . An implicit body representation underlying human position sense. Proc Natl Acad Sci U S A. 2010; 107(26):11727-32. PMC: 2900654. DOI: 10.1073/pnas.1003483107. View

13.

Kalckert A, Perera A, Ganesan Y, Tan E . Rubber hands in space: the role of distance and relative position in the rubber hand illusion. Exp Brain Res. 2019; 237(7):1821-1832. PMC: 6584242. DOI: 10.1007/s00221-019-05539-6. View

14.

Kilteni K, Normand J, Sanchez-Vives M, Slater M . Extending body space in immersive virtual reality: a very long arm illusion. PLoS One. 2012; 7(7):e40867. PMC: 3400672. DOI: 10.1371/journal.pone.0040867. View

15.

Shimada S, Fukuda K, Hiraki K . Rubber hand illusion under delayed visual feedback. PLoS One. 2009; 4(7):e6185. PMC: 2702687. DOI: 10.1371/journal.pone.0006185. View

16.

DAlonzo M, Mioli A, Formica D, Vollero L, Pino G . Different level of virtualization of sight and touch produces the uncanny valley of avatar's hand embodiment. Sci Rep. 2019; 9(1):19030. PMC: 6911036. DOI: 10.1038/s41598-019-55478-z. View

17.

Serino A, Haggard P . Touch and the body. Neurosci Biobehav Rev. 2009; 34(2):224-36. DOI: 10.1016/j.neubiorev.2009.04.004. View

18.

Maselli A, Slater M . The building blocks of the full body ownership illusion. Front Hum Neurosci. 2013; 7:83. PMC: 3604638. DOI: 10.3389/fnhum.2013.00083. View

19.

Slater M, Perez-Marcos D, Ehrsson H, Sanchez-Vives M . Towards a digital body: the virtual arm illusion. Front Hum Neurosci. 2008; 2:6. PMC: 2572198. DOI: 10.3389/neuro.09.006.2008. View

20.

Bruno N, Bertamini M . Haptic perception after a change in hand size. Neuropsychologia. 2010; 48(6):1853-6. DOI: 10.1016/j.neuropsychologia.2010.01.006. View