Complex Regional Pain Syndrome (CRPS) is a condition of chronic pain, swelling, and other symptoms in a limb, which may be partly driven by cortical changes. Patients can have problems with spatial processing, such as locating their affected limb or attending to touch on the affected side of space. Also, pain can be exacerbated by loud noises and ambiguous visual stimuli, suggesting changes in multisensory integration. We investigated localisation and multisensory integration in 14 CRPS patients (7 upper, 7 lower) and 17 controls. Targets appeared briefly on the left or right side of a piece of paper positioned on a table (10 trials/side). Participants indicated the location at which the target had appeared under three guidance conditions: - Visual-only (V): indicating through verbal directions where the target had appeared; - Proprioceptive/Motor-only: touching the target’s location without vision; and - Combined Visual-Proprioceptive/Motor (V-P/M: touching the target’s location with vision. Participants completed each P/M and V-P/M block once with their left and once with their right hand. Estimates of variable error (VE: the sum of the variance of the points in x and y directions) were calculated separately for each condition. Individually, 6/7 upper and 6/7 lower limb patients had VEs in at least one guidance condition that were larger than the upper bound of the 95% confidence interval for the control data, suggesting localisation deficits. Paired comparisons of group data showed that for control participants the VEs in the V-P/M condition were lower relative to both the V and P/M conditions (ps<.0005), consistent with reduced variability during multi-sensory compared to uni-sensory guidance. For patients, VEs in the V-P/M condition were not significantly different to VEs in the V condition (p=.62) nor the P/M condition (p=.27), suggesting a deficit in multisensory integration. The results will be compared to the maximum likelihood estimate. Acknowledgments This research was supported by the Oxford University Press John Fell Fund.
|Publication status||Published - 20 May 2017|
|Event||18th International Multisensory Research Forum - Vanderbilt University, Nashville, USA United States|
Duration: 19 May 2017 → 22 May 2017
|Conference||18th International Multisensory Research Forum|
|Abbreviated title||IMRF 2017|
|Country||USA United States|
|Period||19/05/17 → 22/05/17|