Artikel in Experimental Brain Research
Miranda Smit, Ineke van der Ham en collega’s hebben een artikel gepubliceerd in Experimental Brain Research, getiteld: Body ownership and the absence of touch: Approaching the rubber hand in- and outside peri-hand space. Ze beschrijven hierin de illusie waarbij een rubber hand onderdeel van het lichaam lijkt te zijn en hoe dit beïnvloedt wordt door de suggestie van aanraking.
De samenvatting van het artikel vindt u hier:
It is widely accepted that the integration of visual and tactile information is a necessity to induce ownership over a rubber hand. This idea has recently been challenged by Ferri et al., (2013), as they found that sense of ownership was evident by mere expectation of touch. In our study, we aimed to further investigate this finding, by studying whether the mere potential for touch yields a sense of ownership similar in magnitude to that resulting from actually being touched. We conducted two experiments. In the first experiment our set-up was the classical horizontal set-up (similar to Botvinick and Cohen, 1998). Sixty-three individuals were included and performed the classical conditions (synchronous, asynchronous), an approached but not touched (potential for touch), and a ‘visual only’ condition. In the second experiment, we controlled for differences between the current set-up and the vertical set-up used by Ferri et al., 2013. Fifteen individuals were included and performed a synchronous and various approaching conditions (i.e., vertical approach, horizontal approach, and a control approach (no hands)). In our first experiment we found that approaching the rubber hand neither induced a larger proprioceptive drift nor a stronger subjective sense of ownership than asynchronous stimulation did. Generally, our participants gained most sense of ownership in the synchronous condition, followed by the visual only condition. When using a vertical set-up (second experiment), we confirmed that tactile expectation was able to induce embodiment over a foreign hand, similar in magnitude as actual touch, but only when the real hand was aligned on the vertical axis, thus within along the same trajectory of the approaching stimulus. These and previous results (Ferri, et al., 2013; Ferri et al., 2017) indicate that our brain uses bottom–up sensory information, as well as top-down predictions for building a representation of our body.