Background & Aims

Pain experience arises from the interaction of bottom-up and top-down processes. Distraction away from pain (attentional analgesia) has been demonstrated to effectively modulate pain1. However, there are considerable interindividual differences. The role of psychological and biological factors which may contribute to this variation has yet to be determined. Pain-related negative cognition, such as pain catastrophizing, is suggested to play a role in individual differences in attentional analgesia2,3. However, the contribution of cortical brain structure is not fully described. Here, we investigate the association between attentional analgesia, pain related psychological factors and the structural integrity of functionally relevant cortical regions such as the prefrontal cortex, ACC, and insula.

Methods

Healthy participants (n=87) completed questionnaires regarding pain catastrophizing, pain sensitivity, stress, depression, and anxiety. Participants performed a preregistered cognitive task with different difficulty levels (high and low cognitive load) while they received an individually calibrated painful heat stimulation with two different levels (high and low heat pain). After each trial, participants rated the perceived painful stimulation on a VAS100 scale. The amount of attentional analgesia was quantified by contrasting the mean ratings between trials of low and high cognitive load. Additionally, a high-resolution anatomical image was acquired in a subset of participant (n=34). The effect of the cognitive task was statistically tested with ANOVA. Correlation analysis between questionnaire scores and attentional analgesia was performed. Cortical thickness within the insula and the ACC (estimated with Freesurfer) was correlated with attentional analgesia.

Results

The perceived pain intensity was decreased on average by 5.4 points on the VAS100 scale with a considerable heterogeneity between participants (standard deviation 8.9). A significant effect of pain stimulation intensity (F(1,84)=504.5,p<0.001), cognitive load (F(1,84)=30.9, p<0.001) and an interaction effect (F(1,84)= 47.6, p<0.001) were observed. That is, the effect of attentional analgesia depended on the pain stimulation intensity, higher attentional analgesia was achieved with higher stimulation intensity. Negative pain related cognition, stress, anxiety, and depressive scores were not significantly correlated with attentional analgesia (p>0.05). We are currently performing the brain imaging analyses regarding structure-function associations and preliminary results will be presented at the conference.

Conclusions

Attentional distraction was a robust way to decrease the perceived pain intensity, however, considerable individual differences were observed. Interestingly, the influence of negative pain related cognition and pain sensitivity could not account for this individual variance, possibly due to the relatively homogenous, healthy young population. Different attentional processes suggested to play a role in attentional analgesia1, which partly contribute to the observed heterogeneity. Additionally, the rating of the experienced pain might also influenced the attention of some participant. Current findings might contribute to understand the psychological and structural biological contributors of attentional analgesia.

References

1.Torta, D. M., Legrain, V., Mouraux, A. & Valentini, E. Attention to pain! A neurocognitive perspective on attentional modulation of pain in neuroimaging studies. Cortex vol. 89 Preprint at https://doi.org/10.1016/j.cortex.2017.01.010 (2017).
2.Campbell, C. M. et al. Catastrophizing delays the analgesic effect of distraction. Pain 149, 202–207 (2010).
3.Rischer, K. M. et al. Distraction from pain: The role of selective attention and pain catastrophizing. Eur J Pain 24, 1880 (2020).

Presenting Author

Balint Kincses

Poster Authors

Balint Kincses

MD, PhD

Universitätsklinikum Essen (AöR)

Lead Author

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Viktor Pfaffenrot

Lead Author

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Katharina Püchner

Lead Author

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Tamas Spisak

University Medicine Essen

Lead Author

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Peter Koopmans

Lead Author

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Ulrike Bingel

University Duisburg-Essen, University Hospital

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Topics

  • Pain Imaging