Reproducibility of spatial summation of pain effect during COVID-19 pandemic

Nastaj, J.; Skalski, J.; Budzisz, A.; Szikszay, T. M.; Swoboda, S.; Kowalska, W.; Nowak, D.; Zbroja, E.; Kruszyna, N.; Jakubinska, M.; Grygny, D.; Polczyk, R.; Malecki, A.; Luedtke, K.; Adamczyk, W. M.

doi:10.1101/2022.09.30.510274

bioRxiv · 10.1101/2022.09.30.510274

Reproducibility of spatial summation of pain effect during COVID-19 pandemic

Nastaj, J.·Skalski, J.·Budzisz, A.·Szikszay, T. M.·Swoboda, S.·Kowalska, W.·Nowak, D.·Zbroja, E.·Kruszyna, N.·Jakubinska, M.·Grygny, D.·Polczyk, R.·Malecki, A.·Luedtke, K.·Adamczyk, W. M.

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Abstract

The purpose of this study was to reproduce the previously observed spatial summation of pain effect (SSp) using non-laboratory procedures and commercial equipment. An additional aim was to explore the association between expectations and SSp. The Cold Pressor Task (CPT) was used to induce SSp. Healthy participants (N=68) immersed their non-dominant hands (divided into 5 segments) into cold water (CPT). Two conditions were used 1) gradual hand immersion (ascending condition) and 2) gradual hand withdrawal (descending condition). Pain intensity was measured on a Visual Analogue Scale (VAS). Psychological factors, such as the participants expectations of pain intensity were also measured on a VAS. Results showed significant SSp (X2(4) = 116.90, p < 0.001), reproduced with non-laboratory equipment in a home-based set-up. Furthermore, two novel findings were observed: i) there was a significant correlation between expectations and perceived pain, indicating a link between pain expectations and SSp, ii) spatial summation increased with the increase in duration exposure to the noxious stimulus (Wald X2(8) = 80.80, p < 0.001). This study suggests that SSp is associated with pain expectations and can be formed by a mixture of excitatory and inhibitory mechanisms potentially driven by temporal characteristics of neural excitation. Moreover, this study proposes a new feasible way to induce SSp using a home-based set-up.

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Nastaj, J., Skalski, J., Budzisz, A., Szikszay, T. M., Swoboda, S., Kowalska, W., Nowak, D., Zbroja, E., Kruszyna, N., Jakubinska, M., Grygny, D., Polczyk, R., Malecki, A., Luedtke, K., Adamczyk, W. M.. 2022-10-03. Reproducibility of spatial summation of pain effect during COVID-19 pandemic. https://doi.org/10.1101/2022.09.30.510274

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