Cognitive Models of Limb Embodiment in Structurally Varying Bodies: A Theoretical Perspective

Overview

Journal Front Psychol

Date 2022 Jan 10

PMID 35002827

Authors

Adna Bliek

Robin Bekrater-Bodmann

Philipp Beckerle

Affiliations

Soon will be listed here.

Abstract

Using the seminal rubber hand illusion and related paradigms, the last two decades unveiled the multisensory mechanisms underlying the sense of limb embodiment, that is, the cognitive integration of an artificial limb into one's body representation. Since also individuals with amputations can be induced to embody an artificial limb by multimodal sensory stimulation, it can be assumed that the involved computational mechanisms are universal and independent of the perceiver's physical integrity. This is anything but trivial, since experimentally induced embodiment has been related to the embodiment of prostheses in limb amputees, representing a crucial rehabilitative goal with clinical implications. However, until now there is no unified theoretical framework to explain limb embodiment in structurally varying bodies. In the present work, we suggest extensions of the existing Bayesian models on limb embodiment in normally-limbed persons in order to apply them to the specific situation in limb amputees lacking the limb as physical effector. We propose that adjusted weighting of included parameters of a unified modeling framework, rather than qualitatively different model structures for normally-limbed and amputated individuals, is capable of explaining embodiment in structurally varying bodies. Differences in the spatial representation of the close environment (peripersonal space) and the limb (phantom limb awareness) as well as sensorimotor learning processes associated with limb loss and the use of prostheses might be crucial modulators for embodiment of artificial limbs in individuals with limb amputation. We will discuss implications of our extended Bayesian model for basic research and clinical contexts.

References

Longo M, Schuur F, Kammers M, Tsakiris M, Haggard P . What is embodiment? A psychometric approach. Cognition. 2008; 107(3):978-98. DOI: 10.1016/j.cognition.2007.12.004. View

Press C, Kok P, Yon D . The Perceptual Prediction Paradox. Trends Cogn Sci. 2019; 24(1):13-24. DOI: 10.1016/j.tics.2019.11.003. View

Graham J . Some topographical connections of the striate cortex with subcortical structures in Macaca fascicularis. Exp Brain Res. 1982; 47(1):1-14. DOI: 10.1007/BF00235880. View

Bekrater-Bodmann R . Factors Associated With Prosthesis Embodiment and Its Importance for Prosthetic Satisfaction in Lower Limb Amputees. Front Neurorobot. 2021; 14:604376. PMC: 7843383. DOI: 10.3389/fnbot.2020.604376. View

Lloyd D . Spatial limits on referred touch to an alien limb may reflect boundaries of visuo-tactile peripersonal space surrounding the hand. Brain Cogn. 2006; 64(1):104-9. DOI: 10.1016/j.bandc.2006.09.013. View

Kording K, Beierholm U, Ma W, Quartz S, Tenenbaum J, Shams L . Causal inference in multisensory perception. PLoS One. 2007; 2(9):e943. PMC: 1978520. DOI: 10.1371/journal.pone.0000943. View

Shams L, Beierholm U . Bayesian causal inference: A unifying neuroscience theory. Neurosci Biobehav Rev. 2022; 137:104619. DOI: 10.1016/j.neubiorev.2022.104619. View

Samad M, Chung A, Shams L . Perception of body ownership is driven by Bayesian sensory inference. PLoS One. 2015; 10(2):e0117178. PMC: 4320053. DOI: 10.1371/journal.pone.0117178. View

Flogel M, Kalveram K, Christ O, Vogt J . Application of the rubber hand illusion paradigm: comparison between upper and lower limbs. Psychol Res. 2015; 80(2):298-306. DOI: 10.1007/s00426-015-0650-4. View

10.

Berniker M, Kording K . Bayesian approaches to sensory integration for motor control. Wiley Interdiscip Rev Cogn Sci. 2015; 2(4):419-428. DOI: 10.1002/wcs.125. View

11.

Parise C, Harrar V, Ernst M, Spence C . Cross-correlation between auditory and visual signals promotes multisensory integration. Multisens Res. 2013; 26(3):307-16. DOI: 10.1163/22134808-00002417. View

12.

Bekrater-Bodmann R, Foell J, Diers M, Kamping S, Rance M, Kirsch P . The importance of synchrony and temporal order of visual and tactile input for illusory limb ownership experiences - an FMRI study applying virtual reality. PLoS One. 2014; 9(1):e87013. PMC: 3909015. DOI: 10.1371/journal.pone.0087013. View

13.

Kording K, Wolpert D . Bayesian decision theory in sensorimotor control. Trends Cogn Sci. 2006; 10(7):319-26. DOI: 10.1016/j.tics.2006.05.003. View

14.

Schurmann T, Mohler B, Peters J, Beckerle P . How Cognitive Models of Human Body Experience Might Push Robotics. Front Neurorobot. 2019; 13:14. PMC: 6470381. DOI: 10.3389/fnbot.2019.00014. View

15.

Farmer H, Tajadura-Jimenez A, Tsakiris M . Beyond the colour of my skin: how skin colour affects the sense of body-ownership. Conscious Cogn. 2012; 21(3):1242-56. PMC: 3772504. DOI: 10.1016/j.concog.2012.04.011. View

16.

Parise C, Spence C, Ernst M . When correlation implies causation in multisensory integration. Curr Biol. 2011; 22(1):46-9. DOI: 10.1016/j.cub.2011.11.039. View

17.

Brozzoli C, Gentile G, Ehrsson H . That's near my hand! Parietal and premotor coding of hand-centered space contributes to localization and self-attribution of the hand. J Neurosci. 2012; 32(42):14573-82. PMC: 6621451. DOI: 10.1523/JNEUROSCI.2660-12.2012. View

18.

Ramachandran V, Stewart M . Perceptual correlates of massive cortical reorganization. Science. 1992; 258(5085):1159-60. DOI: 10.1126/science.1439826. View

19.

Bekrater-Bodmann R . Perceptual correlates of successful body-prosthesis interaction in lower limb amputees: psychometric characterisation and development of the Prosthesis Embodiment Scale. Sci Rep. 2020; 10(1):14203. PMC: 7450092. DOI: 10.1038/s41598-020-70828-y. View

20.

Serino A . Peripersonal space (PPS) as a multisensory interface between the individual and the environment, defining the space of the self. Neurosci Biobehav Rev. 2019; 99:138-159. DOI: 10.1016/j.neubiorev.2019.01.016. View