Medical education and distrust modulate the response of insular-cingulate network and ventral striatum in pain diagnosis

Healthcare providers often underestimate patients’ pain, sometimes even when aware of their reports. This could be the effect of experience reducing sensitivity to others pain, or distrust toward patients’ self-evaluations. Across multiple experiments (375 participants), we tested whether senior medical students differed from younger colleagues and lay controls in the way they assess people’s pain and take into consideration their feedback. We found that medical training affected the sensitivity to pain faces, an effect shown by the lower ratings and highlighted by a decrease in neural response of the insula and cingulate cortex. Instead, distrust toward the expressions’ authenticity affected the processing of feedbacks, by decreasing activity in the ventral striatum whenever patients’ self-reports matched participants’ evaluations, and by promoting strong reliance on the opinion of other doctors. Overall, our study underscores the multiple processes which might influence the evaluation of others’ pain at the early stages of medical career.


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"For this experiment, 28 experienced medical students (EMS) enrolled to the 5th and 6th year of medicine at the University of Geneva, responded to our recruitment call. Two of them were excluded, due to [...]. Therefore, the final sample of EMS was composed by 26 participants (9 males, age= 24.15 ± 1.40). EMS participants were associated with a matched control group of 26 students not enrolled in medical-related faculties (13 males, age= 23.73 ± 4.11)." ("Methods" section; "Experiment 2" subsection; "Participants" subsubsection). 2 Please outline where this information can be found within the submission (e.g., sections or figure legends), or explain why this information doesn't apply to your submission: In this study the main paradigm was tested twice, once in a population of 120 participants in Experiment 1, and a second time in a population of 52 participants in Experiment 2. This information is available throughout the manuscript. E.g.: Also the secondary task (Implicit Association Task), was repeated twice across the study (in an population of 155 subjects in Pilot 1, and in the 52 participants from Experiment 2), with replicated effects. This was explicitly displayed in Figure 2, and mentioned in the results section "Through an implicit association task (IAT), we found that EMS showed stronger positive disposition towards the category of MPs (relative to non-MPs), an effect which was less pronounced in Controls and less experienced students (see Figure 2A; see also Figure 2D for a similar effect in subjects from Experiment 2).

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Finally, in Experiment 2 we encountered two participants who did not comply with the task instructions, and as such were excluded. This is explicitly mentioned in the methods section.

"For this experiment, 28 experienced medical students (EMS) enrolled to the 5th and 6th
year of medicine at the University of Geneva, responded to our recruitment call. Two of them were excluded due to non-compliance with the task. Therefore, the final sample of EMS was composed by 26 participants (9 males, age= 24.15 ± 1.40)." ("Methods" section; "Experiment 2" subsection; "Participants" sub-subsection).
In our study we have no genetic/sequence data. We do have neural response evoked from Experiment 2 which are uploaded in the Neurovault repository: https://neurovault.org/collections/9006/ Detailed information on the statistical approached used can be found in the paragraph "Data Analysis" from the section "Methods" of each experiment.
Our group sizes are always N ≥ 26. In our figures we always display individual data-points, superimposed to boxplots/regression lines. In such was the reader can have a direct access of the data distribution underlying our effects.

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Effect sizes of linear models of behavioural and neural activity are reported in terms of parameter estimates (b for Linear Mixed Models on behavioural responses; β for general linear models on brain responses). Effects' sizes on linear regressions are reported in terms of Spearman's ρ.
Finally, in the text p-values are always reported in exact form. In Figures/Tables, however, significant tests are displayed according the following legend "***", "**", and "*" referring to p < 0.001, p < 0.01 and p < 0.05.
Our grouping factor was based on participants' educational choices. Hence, the use of masking allocation strategies was not relevant for this study.
Participants' recruitment as well as inclusion criteria are indicated in the Methods section "Participants" for both experiments. E.g.,  Geneva and Lausanne (1st year=14,2nd year=16,3rd year,N = 15;4th year,N = 15;5th year,N = 17;6th year, N = 13)." ("Methods" section; "Experiment 1" subsection; "Participants" sub-subsection). Additional data files ("source data") • We encourage you to upload relevant additional data files, such as numerical data that are represented as a graph in a figure, or as a summary table • Where provided, these should be in the most useful format, and they can be uploaded as "Source data" files linked to a main figure or table • Include model definition files including the full list of parameters used • Include code used for data analysis (e.g., R, MatLab) • Avoid stating that data files are "available upon request" Please indicate the figures or tables for which source data files have been provided: All the results graph depicted in the paper are based on data, which have been made available through certified repositories. Please see the the section of the paper "Data Availability".
"The behavioral data and script are stored and available at the following link: https://osf.io/qnp6m/. The brain imaging data are stored and available at the following link: https://neurovault.org/collections/9006/."