Vanderclausen, Camille
[UCL]
Alamia, Andrea
[UCL]
Filbrich, Lieve
[UCL]
De Volder, Anne
[UCL]
Legrain, Valéry
[UCL]
The perception of somatosensory stimuli on the body implies the use of different reference frames. It has been shown that they are not only mapped according to a somatotopic reference frame. They are also remapped according to spatial external coordinates in order to provide a common framework to integrate information from different sensory modalities into a multisensory representation of the body space and the space immediately surrounding it. This remapping would be mainly shaped by visual experience. Indeed, it has been demonstrated that crossing the hands over the body midline affects the ability to temporally order two tactile stimuli in sighted but not in early blind participants. This experiment aimed to test this hypothesis using a vibrotactile temporal order judgment (TOJ) task adapted with an adaptive PSI method instead of the method of constant stimuli. This method adapts the stimulus onset asynchrony (SOA) presented in each trial according to the participant’s performance in all the previous trials, allowing to measure precisely the sensitivity of each in a task adapted to the ability of each. Results on the slope showed that all participants performed the task better with the hands uncrossed compared to when their hands were crossed. The blind participants had also a better performance than the sighted controls. These results suggest that both groups cannot be differentiated from each other on the basis of the posture when the task is adapted to the performance of each. Nevertheless, analyses of the SOAs presented to each group showed that the mode of the SOAs presented is significantly lower in the uncrossed compared to the crossed condition in sighted controls, but not in blind individuals. Together, these results indicate that a crossing hand effect could be present in both groups, although more variable in the blind, suggesting that the remapping of tactile stimuli in external coordinates should not be only driven by visual experience.
Bibliographic reference |
Vanderclausen, Camille ; Alamia, Andrea ; Filbrich, Lieve ; De Volder, Anne ; Legrain, Valéry. Measuring the sensitivity of tactile temporal order judgment in sighted and blind participants using the PSI method.18th International Multisensory Research Forum (IMRF 2017) (Nashville, du 19/05/2017 au 22/05/2017). |
Permanent URL |
http://hdl.handle.net/2078.1/181721 |