Main task
pain
The main task consisted of ten blocks: two pain baseline blocks, two expectation color blocks, and six pain color blocks (see the flow of the task in Fig. Study design. The study involved two groups that differed in the modality of pain applied: thermal or electrical. Part (After finishing the main task, participants were asked to fill out a questionnaire to assess whether they had figured out the aim of the study and to collect their beliefs about the influence of colors on pain perception (questions in Table End of study questionnaire.